Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels usin...Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels using simulated lignin cracked oil in tandem with hydroalkylation and deoxygenation reactions.First,we investigated the reaction pathway for the hydroalkylation of phenol,which competes with the hydrodeoxygenation form cyclohexane.And then,we investigated the effects of metal catalyst types,the loading amount of metallic,acid dosage,and reactant ratio on the reaction results.The phenol hydroalkylation and hydrodeoxygenation were balanced when 180℃ and 5 MPa H_(2)with the alkanes yield of 95%.By extending the substrate to other lignin-derived phenolics and simulated lignin cracked oil,we obtained the polycyclic alkane fuel with high density of 0.918 g·ml^(-1)and calorific value of41.2 MJ·L^(-1).Besides,the fuel has good low-temperature properties(viscosity of 9.3 mm^(2)·s^(-1)at 20℃ and freezing point below-55℃),which is expected to be used as jet fuel.This work provides a promising way for the easy and green production of high-density fuel directly from real lignin oil.展开更多
Long-term postprandial hyperglycemia is a primary risk factor for developing chronic metabolic diseases such as obesity,type 2 diabetes,and cardiovascular disease.Chronic hyperglycemia induces the glycation of protein...Long-term postprandial hyperglycemia is a primary risk factor for developing chronic metabolic diseases such as obesity,type 2 diabetes,and cardiovascular disease.Chronic hyperglycemia induces the glycation of proteins,oxidative stress,inflammation and increases plasma insulin and lipid concentrations.Insulin resistance is the primary cause of postprandial excursions of blood glucose and lipids.Hyperglycemia can be treated by lowering dietary carbohydrates intake,digestion,and absorption.Various functional foods improve glucose metabolism by increasing insulin sensitivity and inhibitingα-glucosidase in the small intestine.Natural phytochemicals,especially active phenolics are good antioxidants and show anti-inflammatory action and regulate blood glucose.This review aimed to report on hypoglycemic properties of active phenolics from functional foods and their proposed anti-diabetic mechanisms.Nevertheless,further clinical trials are required to confirm the bioavailability,safety,and efficacy of phenolics,especially the dosage and duration of treatment,to avoid adverse effects and give better dietary recommendations.展开更多
Objective:To detect the in vitro total phenolics,flavonoids contents and antioxidant activity of essential oil,various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah.Methods:The dr...Objective:To detect the in vitro total phenolics,flavonoids contents and antioxidant activity of essential oil,various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah.Methods:The dry powder leaves of Tetrastigma were extracted with different organic solvent such as hexane.ethyl acetate,chloroform,butanol and aqueous methanol.The total phenolic and total flavonoids contents of the essential oil and various organic extracts such as hexane,ethyl acetate,chloroform,butanol and aqueous ethanol were determined by Folin-Ciocalteu method and the assayed antioxidant activity was determined in vitro models such as antioxidant capacity by radical scavenging activity usingα,α-diphenyl-β-picrylhydrazyl (DPPH) method.Results:The total phenolic contents of the essential oil and different extracts as gallic acid equivalents were found to be highest in methanol extract(386.22 mg/g) followed by ethyl acetate(190.89 mg/g).chloroform(175.89 mg/g).hexane(173.44 mg/g).and Imtanol extract (131.72 mg/g) and the phenolic contents not detected in essential oil.The antioxidant capacity of the essential oil and different extracts as ascorbic acid standard was in the order of methanol extract】ethyl acetate extract】chloroform】butanol】hexane extract also the antioxidant activity was not detected in essential oil.Conclusions:The findings show that the extent of antioxidant activity of the essential oil and all extracts are in accordance with the amount of phenolics present in that extract.Leaves of Tetrastigma being rich in phenolics may provide a good source of antioxidant.展开更多
Phyllanthus species plants are a rich source of phenolics and widely used due to their medicinal properties. A liquid chromatography–tandem mass spectrometry(LC–MS/MS) method was developed using high-pressure liquid...Phyllanthus species plants are a rich source of phenolics and widely used due to their medicinal properties. A liquid chromatography–tandem mass spectrometry(LC–MS/MS) method was developed using high-pressure liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry(HPLC-ESI-QTOFMS/MS) for the identification and characterization of quercetin, kaempferol, ellagic acid and their derivatives in ethanolic extracts of Phyllanthus species. The chromatographic separation was carried out on Thermo Betasil C_8 column(250 mm×4.5 mm, 5 μm) using 0.1% formic acid in water and 0.1% formic acid in methanol as the mobile phase. The identification of diagnostic fragment ions and optimization of collision energies were carried out using 21 reference standards. Totally 51 compounds were identified which include 21 compounds identified and characterized unambiguously by comparison with their authentic standards and the remaining 30 were tentatively identified and characterized in ethanolic extracts of P. emblica, P. fraternus, P. amarus and P.niruri.展开更多
Rubus fruits are rich in nutrition with a wide range of phytochemical and consumed by humans,but many of its wild varieties are not commercially useful.Phytochemical exploration of these wild fruits could improve the ...Rubus fruits are rich in nutrition with a wide range of phytochemical and consumed by humans,but many of its wild varieties are not commercially useful.Phytochemical exploration of these wild fruits could improve the commercial usage of these Rubus species.This study focuses to analyze the phytochemical,antioxidant and cytotoxicity of three wild Rubus ellipticus,R.niveus and R.fairholmianus fruits comparatively,which has not revealed.The in vitro antioxidant studies indicated the ethyl acetate and methanol extracts of studied Rubus species competent in scavenging different stable and generated radical.The correlation and regression analysis also statistically supported the contents in the extracts could act against various radicals.Correlation between phytochemical constituent and radical scavenging activity found to be highly positive.The results acquired from this investigation revealed that they are equally competent and could be recommended as dietary supplements or as nutraceuticals.展开更多
Plants were collected and prepared for chemical analysis, total phenolics, anthocyanins concentrations, and free radical scavenging activity. Results showed that, protein concentration of Malva parviflora (22.9%) was ...Plants were collected and prepared for chemical analysis, total phenolics, anthocyanins concentrations, and free radical scavenging activity. Results showed that, protein concentration of Malva parviflora (22.9%) was the highest among the plants. Ruta chalepensis had high levels of fat and carbohydrates (4.2% and 51.7%, respectively), but had the lowest level of ash (8.7%). Mineral concentrations varied and found to have appreciable amounts of Ca, Na, K, Cu, Fe, Mg, Mn, Zn and P. Total phenolic ranged from 163.1 (Tetragonolobus palaestinus) to 1328.8 mg GAE/100g (Ruta chalepensis). Anthocyanins ranged between 18.1 (Gundelia tournefortii) and 100.1 mg/100g (Rumex acetosella). These plants differed in free radical scavenging activity. It was concluded that these plants could be considered as natural sources for antioxidants and valuable natural resources as a new addition to the diet of inhabitants.展开更多
Objective:To search for an efficient and inexpensive source of phytoconstituents with antioxidant potential and health promoting traits from bark and empty pods of Acacia auriculiformis （A.auriculiformis）.Methods:Sa...Objective:To search for an efficient and inexpensive source of phytoconstituents with antioxidant potential and health promoting traits from bark and empty pods of Acacia auriculiformis （A.auriculiformis）.Methods:Samples of bark and empty pod extracts were analyzed for bioactives（phenolics,flavonoids and proanthocyanidins） and subjected to free radical scavenging activity on DPPH<sup>*</sup>,ABTS<sup>?</sup>,OH<sup>?</sup>,O<sub>2</sub><sup>*</sup>,and NO along with the determination of reducing power, iron chelating activity and peroxidation inhibition.Defensive action of extracts on biomolecules and cell membranes were evaluated by DNA nicking assay and haemolysis inhibition assay respectively,α-amylase andα-glucosidase inhibitory potentials were also determined. Results:All the bioactives analyzed were higher in bark（B） than empty pods（EP）[TPC:B （574.51±16.11）;EP（96.80±3.45） mg GAE/g.TFC:B（94.71±7.65）;EP（24（?）87±20.45） mg RE/g. Proanthocyanidins:B（2.81±0.31）;EP（1.25±0.01） mg LE/100 g DM]except flavonoids.Both the extracts showed higher quenching capacity on DPPH and ABTS（DPPH:B（0.21±0.01）;EP（1.51±0.17） g extract/g DPPH.ABTS:B（111 519.14±79 340.91）;EP（80 232.55±32 894.12） mmol TE/g） with the FRAP of B（84 515.63±3 350.69） and EP（47 940.79±1 257.60） mmol Fe（（?））/g.Iron chelation was not observed.In addition,they showed lower quenching activity on OH<sup>?</sup>（B（48.95±1.72）;EP（34.94±1.62）%） and equivalent quenching on O<sub>2</sub><sup>?</sup>（B（53.47±3.92）;EP（24.41±2.61）%）,NO（B（49.04±5.04）; EP（51.00±5.13）%）,peroxidation inhibition（B（67.50±5.50）;EP（55.l±2.3）%） and antihaemolytic potential（B（87.60±6.84）%） towards authentic antioxidant standards.Interestingly,Empty pod extracts are devoid of antihaemolytic activity.Both the extracts showed dose dependent DNA protection.Besides this,bark and empty pod extracts exhibited dual inhibiting potential againstα-amylase andα-glucosidase enzymes.Conclusions:On summarization,it insinuated that both bark and empty pods can be used for the preparation of antioxidant/nutraceutical supplements and in anti-diabetic formulations.展开更多
Folin Ciocalteu (F-C) assay is the most widely used and convenient method to determine the total phenolics content in foods, herbs, and other plant extracts. Different phenolics standards such as gallic acid, ferulic ...Folin Ciocalteu (F-C) assay is the most widely used and convenient method to determine the total phenolics content in foods, herbs, and other plant extracts. Different phenolics standards such as gallic acid, ferulic acid, chlorogenic acid, catechol, and vanillic acid have been used for calibration curves in this assay method. Comparison of these standards, in single or combination of two or more, for more accurate determination of phenolics has not been reported so far. This study tested five single phenolics and seven combinations of mixed phenolic standards to evaluate the optimal standards for F-C method. The different standards were tested to calculate the phenolic content in three known test solutions. We also evaluated interference effect of various compounds in phenolics estimation by F-C method that is usually present in the lignocellulosic biomass-derived sugar solution, and in food products along with phenolics. Finally, the optimal standards with five phenolics were used for the determination of phenolics in alkali pretreated biomass extract. The results indicated that gallic acid was the best standard among the single phenolic compounds and five phenolic compounds solution was the best standard among the mixed phenolic solutions. The presence of glucose, HMF, furfural, and vitamin-B12 did not interfere in phenolic determination;whereas ascorbic acid, tyrosine, formic acid, and acetic acid strongly interfered the results. The results also showed that biomass pelleting process did not affect the generation of phenolics in alkali pretreatment extract.展开更多
Soybean seed is a major source of phytochemical compounds that impact human health nutrition and livestock meal. Charcoal rot is a disease caused by the fungus Macrophomina phaseolina (Tassi) Goid, and thought to infe...Soybean seed is a major source of phytochemical compounds that impact human health nutrition and livestock meal. Charcoal rot is a disease caused by the fungus Macrophomina phaseolina (Tassi) Goid, and thought to infect the plants through roots by a toxin-mediated mechanism, resulting in yield loss and poor seed quality, especially under drought conditions. Limited information is available on the effect of charcoal rot on seed phytochemical compounds and mineral nutrition in soybean. Therefore, the objective of this research was to investigate the effect of charcoal rot infection on seed phenol, seed coat lignin, isoflavones, and minerals using susceptible (S) (DK 3964) and moderately resistant (MR) (AG 3905) maturity group (MG)III soybean cultivars to charcoal rot. A two-year field experiment was conducted, and infested soil with charcoal rot (infested soil conditions, INF) or control (non-infested soil conditions, NINF) was used. The results showed that the moderately resistant genotype had higher concentrations of seed phenolics, total isoflavones, and seed coat lignin under infested and non-infested conditions and under irrigated or non-irrigated conditions compared with the susceptible genotype. The same general trend was found for seed K, Ca, P, Mn, Zn, B, and Cu concentrations in the moderately resistant genotype compared with the susceptible genotype. Our research demonstrated that these seed phytochemical constituents may explain the differences between susceptible and moderately resistant cultivars and may play an important role in the resistance to charcoal rot.展开更多
This study was designed to determine the total phenolic content of 50 herbs and to examine their antioxidant potential. In the sample preparation, 60% ethanol was chosen as the extraction solvent for the subsequent ex...This study was designed to determine the total phenolic content of 50 herbs and to examine their antioxidant potential. In the sample preparation, 60% ethanol was chosen as the extraction solvent for the subsequent experiments. Folin-Cicolteau phenol reagent and a colorimetric method were used to determine the total phenolic content of the selected herbs. The result showed that total phenolic content of those herbs ranged from 2 to 185 mg/g. In antioxidant assay, the ferric reducing/antioxidant power (FRAP) values ranged from 2 to 134 mg GAE/g;the IC50 values of DPPH?·, ·OH and ?scavenging were in the range of 0.06 - 5.50 mg/mL, 0.017 - 0.636 mg/mL and 0.050 - 0.681 mg/mL respectively. Flos caryophylli was the exceptant in the ?scavenging assay because there was no linear relation between the concentration and the scavenging percentage. Compared to gallic acid, ascorbic acid and butylated hydroxytoluene (BHT) in antioxidant assay as positive control, the most potential antioxidant herbs were Cacumen platycladi, Radix et Rhizoma rhei, Rhizoma rhodiolae crenulatae, and Rhizoma sanguisorbae with considerable content of phenolics. Especially, a positive and significant correlation was found between the total phenolic content and FRAP value or DPPH· scavenging percentage.展开更多
Rice straw(RS)collected from Egyptian agricultural environment(Al-Masied village-Alsharqia Governorate-Egypt)was used as substrate for three fungal isolates namely:4b,1Asp,Pleurotus ostreatus NRRL 3501 and mixed cultu...Rice straw(RS)collected from Egyptian agricultural environment(Al-Masied village-Alsharqia Governorate-Egypt)was used as substrate for three fungal isolates namely:4b,1Asp,Pleurotus ostreatus NRRL 3501 and mixed culture of(4b,1Asp).Isolates number 4b and 1Asp were identified using the molecular technique(18S rRNA).Isolate 4b and 1Asp,were identified as Trichoderma saturnisporum MN1-EGY and Aspergillus niger MN2-EGY,respectively.Trichoderma saturnisporum MN1-EGY extract exhibited the highest antimicrobial activity compared to the other fungal extracts.Total phenolic,antimicrobial and antioxidant activities were also determined from the ethyl acetate extract of rice straw inoculated by these fungi.The antioxidant scavenging concentration(SC50)values of the tested samples were 88.84,91.45,94.65 and 100.0μg/ml,respectively for Pleurotus sp.,Aspergiluus niger,Aspergiluus niger+Trichoderma sp.,and Trichoderma sp.,after 15 days incubation,compared to ascorbic acid as positive control with SC50 value equal to 8.0μg/ml.Total phenolic contents(TPCs)were maximum in Pleurotus sp.extract and found to be the most polyphenolic enriched sample(380.64 mg GAE/g dry extract)compared to extracts of Aspergiluusniger,Aspergiluus niger+Trichoderma sp.,and Trichoderma sp.(261.89,198.52,and 119.80 mg GAE/g dry extract),respectively.The GC-MS analysis has been also performed for the promising extracts.展开更多
During the Folin Ciocalteu (F-C) micro-assay for the determination of phenolics in the presence of methanol, fine solids can form. In a previous paper, we hypothesized that the interference from alcohol on the F-C rea...During the Folin Ciocalteu (F-C) micro-assay for the determination of phenolics in the presence of methanol, fine solids can form. In a previous paper, we hypothesized that the interference from alcohol on the F-C reaction can be minimized depending on the particular procedure used to reach the alkalinity condition. In order to demonstrate our hypothesis we studied, by spectrophotometrically monitoring, the time-behaviour of the reactions carried out in the presence of different methanol concentrations at the same alkalinity condition from two protocols. The results showed that the interfering effect of methanol on the F-C micro-method can be affect and even prevented depending on working conditions. In particular, the formation of fine solids can be delayed, slowed down and prevented depending on the initial carbonate concentration used. We have explained why the initial carbonate concentration, used to reach the final alkalinity condition, plays an important role in the F-C reaction carried out in the presence of methanol. Moreover, the results from real-time monitoring showed that, differently from traditional F-C procedure, our procedure allows us to carry out the F-C micro method in the presence of 6% methanol, as an extreme concentration, reading the absorbance at real time 24 min. The real-time monitoring of absorbance can be considered as a useful means to explore the effect of other parameters on precipitate formation caused by the presence of methanol in the F-C reaction.展开更多
Kaempferia parviflora plants derived from in vitro culture were grown in the glasshouse. A comparison of the yield of total phenolics and total flavonoids under varying extraction conditions from rhizomes harvested fr...Kaempferia parviflora plants derived from in vitro culture were grown in the glasshouse. A comparison of the yield of total phenolics and total flavonoids under varying extraction conditions from rhizomes harvested from plants of different ages was undertaken. The results showed that phenolic and flavonoid contents in the rhizomes were highest 8 months after planting. Another study found that 2 g rhizomes extracted in 50 ml of water at 90°C for 120 minutes gave the best yield of phenolics and flavonoids. Under these conditions, an average of 210 mg GAE/g dry weight of total phenolics and 81 μg QCE/g dry weight of total flavonoids were obtained.展开更多
Various phenolic and flavonoid compounds that are secondary plant metabolites are known to contribute to physiological wellbeing. Extraction efficiency of such compounds from plant sources is dependent on the extracti...Various phenolic and flavonoid compounds that are secondary plant metabolites are known to contribute to physiological wellbeing. Extraction efficiency of such compounds from plant sources is dependent on the extraction solvent type and composition, and its pH. In this study, different extraction variables were examined: heating time (20 to 180 min), temperature (60°C, 75°C and 90°C) and pH (2.5, 3.0, 4.0, 5.0, 6.0 and 7.0). Hot water was used in the extraction of dry samples. For phenolics, the most efficient extraction was by using water at 60°C for 180 min, whereby 5.95 mg GA equivalent/dry extract was achieved. The most efficient extraction of flavonoids was achieved with water at 60°C for 150 min, whereby 43 μg Quercetin equivalent/dry extract was obtained. Adjusting the solvent to pH 2.5 increased the yield to 45.3 μg Quercetin equivalent/dry extract.展开更多
The objective of the present study was the recovery and selective separation of phenolics from grape marc and lees, two primary wastes from wine-making industry, with solvent extraction method, optimized using One-Fac...The objective of the present study was the recovery and selective separation of phenolics from grape marc and lees, two primary wastes from wine-making industry, with solvent extraction method, optimized using One-Factor-at-a-Time method (OFAT) and Response Surface Methodology (RSM). Phenolics from the whole fresh grapes have been studied in previous work, but not the valorization of wine wastes and their phenolic content. Extraction resulted in 19, 15 and 10 mg/g (dry weight) total phenolics with 96%, 87% and 64% antioxidant activity from red, white marc and white lees, respectively. Extracts thus obtained were subsequently treated with several sorbents followed by HCl-desorption. NaOH and CH3OH treated zeolite and aluminum oxide, respectively, performed better, separating phenolics up to 93% from total sugars. The latter resulted in a fraction containing up to 50% of the initial phenolics holding the antioxidant activity (up to 85%) of the initial extract. The results indicate the significance of the applied methodology being fast and low cost for the selective recovery of phenolics from wine wastes.展开更多
Thin film composite(TFC) membranes represent a highly promising platform for efficient nanofiltration(NF)processes. However, the improvement in permeance is impeded by the substrates with low permeances. Herein,highly...Thin film composite(TFC) membranes represent a highly promising platform for efficient nanofiltration(NF)processes. However, the improvement in permeance is impeded by the substrates with low permeances. Herein,highly permeable gradient phenolic membranes with tight selectivity are used as substrates to prepare TFC membranes with high permeances by the layer-by-layer assembly method. The negatively charged phenolic substrates are alternately assembled with polycation polyethylenimine(PEI) and polyanion poly(acrylic acid)(PAA)as a result of electrostatic interactions, forming thin and compact PEI/PAA layers tightly attached to the substrate surface. Benefiting from the high permeances and tight surface pores of the gradient nanoporous structures of the substrates, the produced PEI/PAA membranes exhibit a permeance up to 506 L? m-2?h-1?MPa-1, which is ~2–10 times higher than that of other membranes with similar rejections. The PEI/PAA membranes are capable of retaining N 96.1% of negatively charged dyes following the mechanism of electrostatic repulsion. We demonstrate that the membranes can also separate positively and neutrally charged dyes from water via other mechanisms.This work opens a new avenue for the design and preparation of high-flux NF membranes, which is also applicable to enhance the permeance of other TFC membranes.展开更多
Whole grain cereals are important dietary sources for management of metabolic diseases due to the bioactive components they contain.Hence,this study investigated enzymes(pancreatic lipase,-amylase,-glucosidase,xanthin...Whole grain cereals are important dietary sources for management of metabolic diseases due to the bioactive components they contain.Hence,this study investigated enzymes(pancreatic lipase,-amylase,-glucosidase,xanthine oxidase and angiotensin 1-converting enzyme)inhibitory property,antioxidant activity and phenolics profile of raw and roasted red sorghum(Sorghum bicolor)grains in vitro.Extracts of flours of raw and roasted(150◦C and 180◦C,for 20 min)grains were assayed for enzymes inhibitory and antioxidant activities using spectrophotometric methods;while their phenolic constituents were characterized using HPLC-DAD.The raw grains exhibited strong enzymes inhibitory and antioxidant activities,and contained phenolic acids(gallic,chlorogenic,caffeic,ellagic and p-coumaric acids)and flavonoids(quercetin,luteolin and apigenin).However,whereas the enzymes inhibitory activity and levels of the phenolic compounds in the grains decreased significantly(p<0.05)with increasing roasting temperature,the antioxidant activity increased.Hence,roasting at high temperature may not be recommended for the optimum retention of the enzymes inhibitory property and phenolic compounds of red sorghum grains.展开更多
This study sought to investigate the possible mechanisms for the use of phenolic extracts from grapefruit peels in the management/prevention of cardiovascular complications.The effects of the phenolic extracts on key ...This study sought to investigate the possible mechanisms for the use of phenolic extracts from grapefruit peels in the management/prevention of cardiovascular complications.The effects of the phenolic extracts on key enzymes relevant to cardiovascular diseases[3-hydroxy-methyl-3-glutaryl coenzyme A reductase(HMG-CoA reductase)and angiotensin-I converting enzyme(ACE)],cellular antioxidant activity in human endothelial cells(EA.Hy 926)and radicals[1,1-diphenyl-2 picrylhydrazyl(DPPH)and 2,2-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)(ABTS)]scavenging abilities were investigated.The phenolic contents of the extracts were investigated using HPLC–DAD.There was no significant(P>0.05)difference in the HMG-CoA reductase inhibitory ability of the two extracts,while the bound phenolic extracts had a stronger ACE inhibitory ability than the soluble free phenolics.The extracts also showed intracellular antioxidant activity in human endothelial(EA.Hy 926)cells.Furthermore,the bound phenolics had significantly higher radicals(DPPH*and ABTS*)scavenging abilities than the free phenolics.The HPLC analysis revealed the presence of flavonoids(quercetin and kaempferol),phenolics acids(resveratrol,gallic acid,ellagic acid and caffeic acid)and tannin(catechin).The cellular antioxidative properties and inhibition of enzymes relevant to the management of cardiovascular complications showed that grapefruit peels could be used as nutraceuticals for the management of such conditions.展开更多
Salacia oblonga (Wall.) belonging to the family Celastraceae is an important medicinal plant available in India and Sri Lanka. It possesses an array of pharmacological and therapeutic properties. In the present study ...Salacia oblonga (Wall.) belonging to the family Celastraceae is an important medicinal plant available in India and Sri Lanka. It possesses an array of pharmacological and therapeutic properties. In the present study phenolic compounds of S. oblonga methanolic extracts were estimated by high performance liquid chromatography (HPLC) indicating the presence of catechin, quercetin, synapic acid and syringic acid. The study involved evaluation of S. oblonga extracts for cytotoxic and cytoprotective effects on human lymphocytes. Aerial extracts have significant protective activity against hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) induced cytotoxic activity in comparison to the root extracts. The results relate the cytoprotective effect of S. oblonga due to the presence of poly phenols and other phytochemicals, as they have significant ability to remove free radicals or reactive species and might induce the expression of antioxidant enzymes inside the cells.展开更多
Background: Traditional plants, their parts, and phytochemicals obtained from them are beneficial for human beings. They are used as potent antimicrobials, but very little research is conducted on the use of tradition...Background: Traditional plants, their parts, and phytochemicals obtained from them are beneficial for human beings. They are used as potent antimicrobials, but very little research is conducted on the use of traditional medicine against food-borne infection. Different berry plants are rich in phenolic compounds and conventionally known to have many properties such as antioxidants, anti-carcinogenic, anti-inflammatory, anti-bacterial, and anti-diabetics. However, only limited polyphenols are known for their antilisterial effect. The present study aimed to explore the antimicrobial efficacy of phenolic compounds of berries for the treatment of food-borne infection caused by the bacteria Listeria monocytogenes. Materials and Methods: Molecular docking studies employing the Swiss DOCK server were performed to evaluate the antimicrobial activity of phenolic compounds obtained from different varieties of berries. Internalin B(Inl B), a virulence protein of L. monocytogenes was selected as a target. The absorption, distribution, metabolism, excretion, and toxicity profiling of each test ligand was done through the Swiss ADME tool. Results: Among all the test ligands, p-coumaric acid, epicatechins, chlorogenic acid, and quercetin showed better binding efficiency with the target protein Inl B. The binding energy obtained for quercetin, p-coumaric acid, chlorogenic acid, and epicatechins was-8.93,-8.23,-8.18,-7.58, kcal/mol, respectively. Quercetin and p-coumaric acid were forming 4 H-bonds, whereas chlorogenic acid and epicatechins were forming 3-H bonds inside the binding pocket. Conclusion: In a nutshell, analyses indicated that identified ligands have the potential to block the virulent protein Inl B of L. monocytogenes and help combat Listeria infection. These phenolic compounds could be a substitute for synthetic antimicrobials and can be used in food preservation and combat food-borne diseases. However, future in-depth in vitro and in vivo analysis is needed to get more information on these four phenolic ligands of berries.展开更多
基金the support from National Key Research and Development Program of China(2021YFC2104400)the Tianjin Science and Technology Plan Project(21JCQNJC00340)the Haihe Laboratory of Sustainable Chemical Transformations for financial support。
文摘Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels using simulated lignin cracked oil in tandem with hydroalkylation and deoxygenation reactions.First,we investigated the reaction pathway for the hydroalkylation of phenol,which competes with the hydrodeoxygenation form cyclohexane.And then,we investigated the effects of metal catalyst types,the loading amount of metallic,acid dosage,and reactant ratio on the reaction results.The phenol hydroalkylation and hydrodeoxygenation were balanced when 180℃ and 5 MPa H_(2)with the alkanes yield of 95%.By extending the substrate to other lignin-derived phenolics and simulated lignin cracked oil,we obtained the polycyclic alkane fuel with high density of 0.918 g·ml^(-1)and calorific value of41.2 MJ·L^(-1).Besides,the fuel has good low-temperature properties(viscosity of 9.3 mm^(2)·s^(-1)at 20℃ and freezing point below-55℃),which is expected to be used as jet fuel.This work provides a promising way for the easy and green production of high-density fuel directly from real lignin oil.
文摘Long-term postprandial hyperglycemia is a primary risk factor for developing chronic metabolic diseases such as obesity,type 2 diabetes,and cardiovascular disease.Chronic hyperglycemia induces the glycation of proteins,oxidative stress,inflammation and increases plasma insulin and lipid concentrations.Insulin resistance is the primary cause of postprandial excursions of blood glucose and lipids.Hyperglycemia can be treated by lowering dietary carbohydrates intake,digestion,and absorption.Various functional foods improve glucose metabolism by increasing insulin sensitivity and inhibitingα-glucosidase in the small intestine.Natural phytochemicals,especially active phenolics are good antioxidants and show anti-inflammatory action and regulate blood glucose.This review aimed to report on hypoglycemic properties of active phenolics from functional foods and their proposed anti-diabetic mechanisms.Nevertheless,further clinical trials are required to confirm the bioavailability,safety,and efficacy of phenolics,especially the dosage and duration of treatment,to avoid adverse effects and give better dietary recommendations.
基金Biotechnology Research Institute,University Malaysia Sabah,Malaysia for financial support of this entire work
文摘Objective:To detect the in vitro total phenolics,flavonoids contents and antioxidant activity of essential oil,various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah.Methods:The dry powder leaves of Tetrastigma were extracted with different organic solvent such as hexane.ethyl acetate,chloroform,butanol and aqueous methanol.The total phenolic and total flavonoids contents of the essential oil and various organic extracts such as hexane,ethyl acetate,chloroform,butanol and aqueous ethanol were determined by Folin-Ciocalteu method and the assayed antioxidant activity was determined in vitro models such as antioxidant capacity by radical scavenging activity usingα,α-diphenyl-β-picrylhydrazyl (DPPH) method.Results:The total phenolic contents of the essential oil and different extracts as gallic acid equivalents were found to be highest in methanol extract(386.22 mg/g) followed by ethyl acetate(190.89 mg/g).chloroform(175.89 mg/g).hexane(173.44 mg/g).and Imtanol extract (131.72 mg/g) and the phenolic contents not detected in essential oil.The antioxidant capacity of the essential oil and different extracts as ascorbic acid standard was in the order of methanol extract】ethyl acetate extract】chloroform】butanol】hexane extract also the antioxidant activity was not detected in essential oil.Conclusions:The findings show that the extent of antioxidant activity of the essential oil and all extracts are in accordance with the amount of phenolics present in that extract.Leaves of Tetrastigma being rich in phenolics may provide a good source of antioxidant.
基金CSIR, New Delhi, India, for financial supportBK for NMPB grant GO/UP/03/09
文摘Phyllanthus species plants are a rich source of phenolics and widely used due to their medicinal properties. A liquid chromatography–tandem mass spectrometry(LC–MS/MS) method was developed using high-pressure liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry(HPLC-ESI-QTOFMS/MS) for the identification and characterization of quercetin, kaempferol, ellagic acid and their derivatives in ethanolic extracts of Phyllanthus species. The chromatographic separation was carried out on Thermo Betasil C_8 column(250 mm×4.5 mm, 5 μm) using 0.1% formic acid in water and 0.1% formic acid in methanol as the mobile phase. The identification of diagnostic fragment ions and optimization of collision energies were carried out using 21 reference standards. Totally 51 compounds were identified which include 21 compounds identified and characterized unambiguously by comparison with their authentic standards and the remaining 30 were tentatively identified and characterized in ethanolic extracts of P. emblica, P. fraternus, P. amarus and P.niruri.
基金All the authors acknowledge the University Grants Commission(UGC)–Special Assistance Programme[Ref No:F.5-16/2016/DRS-1(SAP-II)]in Department of Botany,Bharathiar University,Coimbatore,India for granting the instrument facilities during the research work.The first author gratefully acknowledges to University Grants Commission,India for the Rajiv Gandhi National Fellowship(Ref No.F1-17.1/2017-18/RGNF-2017-18-SCTAM-37934).
文摘Rubus fruits are rich in nutrition with a wide range of phytochemical and consumed by humans,but many of its wild varieties are not commercially useful.Phytochemical exploration of these wild fruits could improve the commercial usage of these Rubus species.This study focuses to analyze the phytochemical,antioxidant and cytotoxicity of three wild Rubus ellipticus,R.niveus and R.fairholmianus fruits comparatively,which has not revealed.The in vitro antioxidant studies indicated the ethyl acetate and methanol extracts of studied Rubus species competent in scavenging different stable and generated radical.The correlation and regression analysis also statistically supported the contents in the extracts could act against various radicals.Correlation between phytochemical constituent and radical scavenging activity found to be highly positive.The results acquired from this investigation revealed that they are equally competent and could be recommended as dietary supplements or as nutraceuticals.
文摘Plants were collected and prepared for chemical analysis, total phenolics, anthocyanins concentrations, and free radical scavenging activity. Results showed that, protein concentration of Malva parviflora (22.9%) was the highest among the plants. Ruta chalepensis had high levels of fat and carbohydrates (4.2% and 51.7%, respectively), but had the lowest level of ash (8.7%). Mineral concentrations varied and found to have appreciable amounts of Ca, Na, K, Cu, Fe, Mg, Mn, Zn and P. Total phenolic ranged from 163.1 (Tetragonolobus palaestinus) to 1328.8 mg GAE/100g (Ruta chalepensis). Anthocyanins ranged between 18.1 (Gundelia tournefortii) and 100.1 mg/100g (Rumex acetosella). These plants differed in free radical scavenging activity. It was concluded that these plants could be considered as natural sources for antioxidants and valuable natural resources as a new addition to the diet of inhabitants.
基金University Grants Commission (UGC),New Delhi,India(F.No.34-259\2008)for the financial assistance
文摘Objective:To search for an efficient and inexpensive source of phytoconstituents with antioxidant potential and health promoting traits from bark and empty pods of Acacia auriculiformis （A.auriculiformis）.Methods:Samples of bark and empty pod extracts were analyzed for bioactives（phenolics,flavonoids and proanthocyanidins） and subjected to free radical scavenging activity on DPPH<sup>*</sup>,ABTS<sup>?</sup>,OH<sup>?</sup>,O<sub>2</sub><sup>*</sup>,and NO along with the determination of reducing power, iron chelating activity and peroxidation inhibition.Defensive action of extracts on biomolecules and cell membranes were evaluated by DNA nicking assay and haemolysis inhibition assay respectively,α-amylase andα-glucosidase inhibitory potentials were also determined. Results:All the bioactives analyzed were higher in bark（B） than empty pods（EP）[TPC:B （574.51±16.11）;EP（96.80±3.45） mg GAE/g.TFC:B（94.71±7.65）;EP（24（?）87±20.45） mg RE/g. Proanthocyanidins:B（2.81±0.31）;EP（1.25±0.01） mg LE/100 g DM]except flavonoids.Both the extracts showed higher quenching capacity on DPPH and ABTS（DPPH:B（0.21±0.01）;EP（1.51±0.17） g extract/g DPPH.ABTS:B（111 519.14±79 340.91）;EP（80 232.55±32 894.12） mmol TE/g） with the FRAP of B（84 515.63±3 350.69） and EP（47 940.79±1 257.60） mmol Fe（（?））/g.Iron chelation was not observed.In addition,they showed lower quenching activity on OH<sup>?</sup>（B（48.95±1.72）;EP（34.94±1.62）%） and equivalent quenching on O<sub>2</sub><sup>?</sup>（B（53.47±3.92）;EP（24.41±2.61）%）,NO（B（49.04±5.04）; EP（51.00±5.13）%）,peroxidation inhibition（B（67.50±5.50）;EP（55.l±2.3）%） and antihaemolytic potential（B（87.60±6.84）%） towards authentic antioxidant standards.Interestingly,Empty pod extracts are devoid of antihaemolytic activity.Both the extracts showed dose dependent DNA protection.Besides this,bark and empty pod extracts exhibited dual inhibiting potential againstα-amylase andα-glucosidase enzymes.Conclusions:On summarization,it insinuated that both bark and empty pods can be used for the preparation of antioxidant/nutraceutical supplements and in anti-diabetic formulations.
文摘Folin Ciocalteu (F-C) assay is the most widely used and convenient method to determine the total phenolics content in foods, herbs, and other plant extracts. Different phenolics standards such as gallic acid, ferulic acid, chlorogenic acid, catechol, and vanillic acid have been used for calibration curves in this assay method. Comparison of these standards, in single or combination of two or more, for more accurate determination of phenolics has not been reported so far. This study tested five single phenolics and seven combinations of mixed phenolic standards to evaluate the optimal standards for F-C method. The different standards were tested to calculate the phenolic content in three known test solutions. We also evaluated interference effect of various compounds in phenolics estimation by F-C method that is usually present in the lignocellulosic biomass-derived sugar solution, and in food products along with phenolics. Finally, the optimal standards with five phenolics were used for the determination of phenolics in alkali pretreated biomass extract. The results indicated that gallic acid was the best standard among the single phenolic compounds and five phenolic compounds solution was the best standard among the mixed phenolic solutions. The presence of glucose, HMF, furfural, and vitamin-B12 did not interfere in phenolic determination;whereas ascorbic acid, tyrosine, formic acid, and acetic acid strongly interfered the results. The results also showed that biomass pelleting process did not affect the generation of phenolics in alkali pretreatment extract.
文摘Soybean seed is a major source of phytochemical compounds that impact human health nutrition and livestock meal. Charcoal rot is a disease caused by the fungus Macrophomina phaseolina (Tassi) Goid, and thought to infect the plants through roots by a toxin-mediated mechanism, resulting in yield loss and poor seed quality, especially under drought conditions. Limited information is available on the effect of charcoal rot on seed phytochemical compounds and mineral nutrition in soybean. Therefore, the objective of this research was to investigate the effect of charcoal rot infection on seed phenol, seed coat lignin, isoflavones, and minerals using susceptible (S) (DK 3964) and moderately resistant (MR) (AG 3905) maturity group (MG)III soybean cultivars to charcoal rot. A two-year field experiment was conducted, and infested soil with charcoal rot (infested soil conditions, INF) or control (non-infested soil conditions, NINF) was used. The results showed that the moderately resistant genotype had higher concentrations of seed phenolics, total isoflavones, and seed coat lignin under infested and non-infested conditions and under irrigated or non-irrigated conditions compared with the susceptible genotype. The same general trend was found for seed K, Ca, P, Mn, Zn, B, and Cu concentrations in the moderately resistant genotype compared with the susceptible genotype. Our research demonstrated that these seed phytochemical constituents may explain the differences between susceptible and moderately resistant cultivars and may play an important role in the resistance to charcoal rot.
文摘This study was designed to determine the total phenolic content of 50 herbs and to examine their antioxidant potential. In the sample preparation, 60% ethanol was chosen as the extraction solvent for the subsequent experiments. Folin-Cicolteau phenol reagent and a colorimetric method were used to determine the total phenolic content of the selected herbs. The result showed that total phenolic content of those herbs ranged from 2 to 185 mg/g. In antioxidant assay, the ferric reducing/antioxidant power (FRAP) values ranged from 2 to 134 mg GAE/g;the IC50 values of DPPH?·, ·OH and ?scavenging were in the range of 0.06 - 5.50 mg/mL, 0.017 - 0.636 mg/mL and 0.050 - 0.681 mg/mL respectively. Flos caryophylli was the exceptant in the ?scavenging assay because there was no linear relation between the concentration and the scavenging percentage. Compared to gallic acid, ascorbic acid and butylated hydroxytoluene (BHT) in antioxidant assay as positive control, the most potential antioxidant herbs were Cacumen platycladi, Radix et Rhizoma rhei, Rhizoma rhodiolae crenulatae, and Rhizoma sanguisorbae with considerable content of phenolics. Especially, a positive and significant correlation was found between the total phenolic content and FRAP value or DPPH· scavenging percentage.
文摘Rice straw(RS)collected from Egyptian agricultural environment(Al-Masied village-Alsharqia Governorate-Egypt)was used as substrate for three fungal isolates namely:4b,1Asp,Pleurotus ostreatus NRRL 3501 and mixed culture of(4b,1Asp).Isolates number 4b and 1Asp were identified using the molecular technique(18S rRNA).Isolate 4b and 1Asp,were identified as Trichoderma saturnisporum MN1-EGY and Aspergillus niger MN2-EGY,respectively.Trichoderma saturnisporum MN1-EGY extract exhibited the highest antimicrobial activity compared to the other fungal extracts.Total phenolic,antimicrobial and antioxidant activities were also determined from the ethyl acetate extract of rice straw inoculated by these fungi.The antioxidant scavenging concentration(SC50)values of the tested samples were 88.84,91.45,94.65 and 100.0μg/ml,respectively for Pleurotus sp.,Aspergiluus niger,Aspergiluus niger+Trichoderma sp.,and Trichoderma sp.,after 15 days incubation,compared to ascorbic acid as positive control with SC50 value equal to 8.0μg/ml.Total phenolic contents(TPCs)were maximum in Pleurotus sp.extract and found to be the most polyphenolic enriched sample(380.64 mg GAE/g dry extract)compared to extracts of Aspergiluusniger,Aspergiluus niger+Trichoderma sp.,and Trichoderma sp.(261.89,198.52,and 119.80 mg GAE/g dry extract),respectively.The GC-MS analysis has been also performed for the promising extracts.
文摘During the Folin Ciocalteu (F-C) micro-assay for the determination of phenolics in the presence of methanol, fine solids can form. In a previous paper, we hypothesized that the interference from alcohol on the F-C reaction can be minimized depending on the particular procedure used to reach the alkalinity condition. In order to demonstrate our hypothesis we studied, by spectrophotometrically monitoring, the time-behaviour of the reactions carried out in the presence of different methanol concentrations at the same alkalinity condition from two protocols. The results showed that the interfering effect of methanol on the F-C micro-method can be affect and even prevented depending on working conditions. In particular, the formation of fine solids can be delayed, slowed down and prevented depending on the initial carbonate concentration used. We have explained why the initial carbonate concentration, used to reach the final alkalinity condition, plays an important role in the F-C reaction carried out in the presence of methanol. Moreover, the results from real-time monitoring showed that, differently from traditional F-C procedure, our procedure allows us to carry out the F-C micro method in the presence of 6% methanol, as an extreme concentration, reading the absorbance at real time 24 min. The real-time monitoring of absorbance can be considered as a useful means to explore the effect of other parameters on precipitate formation caused by the presence of methanol in the F-C reaction.
文摘Kaempferia parviflora plants derived from in vitro culture were grown in the glasshouse. A comparison of the yield of total phenolics and total flavonoids under varying extraction conditions from rhizomes harvested from plants of different ages was undertaken. The results showed that phenolic and flavonoid contents in the rhizomes were highest 8 months after planting. Another study found that 2 g rhizomes extracted in 50 ml of water at 90°C for 120 minutes gave the best yield of phenolics and flavonoids. Under these conditions, an average of 210 mg GAE/g dry weight of total phenolics and 81 μg QCE/g dry weight of total flavonoids were obtained.
文摘Various phenolic and flavonoid compounds that are secondary plant metabolites are known to contribute to physiological wellbeing. Extraction efficiency of such compounds from plant sources is dependent on the extraction solvent type and composition, and its pH. In this study, different extraction variables were examined: heating time (20 to 180 min), temperature (60°C, 75°C and 90°C) and pH (2.5, 3.0, 4.0, 5.0, 6.0 and 7.0). Hot water was used in the extraction of dry samples. For phenolics, the most efficient extraction was by using water at 60°C for 180 min, whereby 5.95 mg GA equivalent/dry extract was achieved. The most efficient extraction of flavonoids was achieved with water at 60°C for 150 min, whereby 43 μg Quercetin equivalent/dry extract was obtained. Adjusting the solvent to pH 2.5 increased the yield to 45.3 μg Quercetin equivalent/dry extract.
文摘The objective of the present study was the recovery and selective separation of phenolics from grape marc and lees, two primary wastes from wine-making industry, with solvent extraction method, optimized using One-Factor-at-a-Time method (OFAT) and Response Surface Methodology (RSM). Phenolics from the whole fresh grapes have been studied in previous work, but not the valorization of wine wastes and their phenolic content. Extraction resulted in 19, 15 and 10 mg/g (dry weight) total phenolics with 96%, 87% and 64% antioxidant activity from red, white marc and white lees, respectively. Extracts thus obtained were subsequently treated with several sorbents followed by HCl-desorption. NaOH and CH3OH treated zeolite and aluminum oxide, respectively, performed better, separating phenolics up to 93% from total sugars. The latter resulted in a fraction containing up to 50% of the initial phenolics holding the antioxidant activity (up to 85%) of the initial extract. The results indicate the significance of the applied methodology being fast and low cost for the selective recovery of phenolics from wine wastes.
基金Supported by the National Basic Research Program of China(2015CB655301)the Natural Science Foundation of China(21825803)+2 种基金and the Natural Science Foundation of Jiangsu Province(BK20150063)the Program of Excellent Innovation Teams of Jiangsu Higher Education Institutionsthe Project of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Thin film composite(TFC) membranes represent a highly promising platform for efficient nanofiltration(NF)processes. However, the improvement in permeance is impeded by the substrates with low permeances. Herein,highly permeable gradient phenolic membranes with tight selectivity are used as substrates to prepare TFC membranes with high permeances by the layer-by-layer assembly method. The negatively charged phenolic substrates are alternately assembled with polycation polyethylenimine(PEI) and polyanion poly(acrylic acid)(PAA)as a result of electrostatic interactions, forming thin and compact PEI/PAA layers tightly attached to the substrate surface. Benefiting from the high permeances and tight surface pores of the gradient nanoporous structures of the substrates, the produced PEI/PAA membranes exhibit a permeance up to 506 L? m-2?h-1?MPa-1, which is ~2–10 times higher than that of other membranes with similar rejections. The PEI/PAA membranes are capable of retaining N 96.1% of negatively charged dyes following the mechanism of electrostatic repulsion. We demonstrate that the membranes can also separate positively and neutrally charged dyes from water via other mechanisms.This work opens a new avenue for the design and preparation of high-flux NF membranes, which is also applicable to enhance the permeance of other TFC membranes.
文摘Whole grain cereals are important dietary sources for management of metabolic diseases due to the bioactive components they contain.Hence,this study investigated enzymes(pancreatic lipase,-amylase,-glucosidase,xanthine oxidase and angiotensin 1-converting enzyme)inhibitory property,antioxidant activity and phenolics profile of raw and roasted red sorghum(Sorghum bicolor)grains in vitro.Extracts of flours of raw and roasted(150◦C and 180◦C,for 20 min)grains were assayed for enzymes inhibitory and antioxidant activities using spectrophotometric methods;while their phenolic constituents were characterized using HPLC-DAD.The raw grains exhibited strong enzymes inhibitory and antioxidant activities,and contained phenolic acids(gallic,chlorogenic,caffeic,ellagic and p-coumaric acids)and flavonoids(quercetin,luteolin and apigenin).However,whereas the enzymes inhibitory activity and levels of the phenolic compounds in the grains decreased significantly(p<0.05)with increasing roasting temperature,the antioxidant activity increased.Hence,roasting at high temperature may not be recommended for the optimum retention of the enzymes inhibitory property and phenolic compounds of red sorghum grains.
文摘This study sought to investigate the possible mechanisms for the use of phenolic extracts from grapefruit peels in the management/prevention of cardiovascular complications.The effects of the phenolic extracts on key enzymes relevant to cardiovascular diseases[3-hydroxy-methyl-3-glutaryl coenzyme A reductase(HMG-CoA reductase)and angiotensin-I converting enzyme(ACE)],cellular antioxidant activity in human endothelial cells(EA.Hy 926)and radicals[1,1-diphenyl-2 picrylhydrazyl(DPPH)and 2,2-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)(ABTS)]scavenging abilities were investigated.The phenolic contents of the extracts were investigated using HPLC–DAD.There was no significant(P>0.05)difference in the HMG-CoA reductase inhibitory ability of the two extracts,while the bound phenolic extracts had a stronger ACE inhibitory ability than the soluble free phenolics.The extracts also showed intracellular antioxidant activity in human endothelial(EA.Hy 926)cells.Furthermore,the bound phenolics had significantly higher radicals(DPPH*and ABTS*)scavenging abilities than the free phenolics.The HPLC analysis revealed the presence of flavonoids(quercetin and kaempferol),phenolics acids(resveratrol,gallic acid,ellagic acid and caffeic acid)and tannin(catechin).The cellular antioxidative properties and inhibition of enzymes relevant to the management of cardiovascular complications showed that grapefruit peels could be used as nutraceuticals for the management of such conditions.
文摘Salacia oblonga (Wall.) belonging to the family Celastraceae is an important medicinal plant available in India and Sri Lanka. It possesses an array of pharmacological and therapeutic properties. In the present study phenolic compounds of S. oblonga methanolic extracts were estimated by high performance liquid chromatography (HPLC) indicating the presence of catechin, quercetin, synapic acid and syringic acid. The study involved evaluation of S. oblonga extracts for cytotoxic and cytoprotective effects on human lymphocytes. Aerial extracts have significant protective activity against hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) induced cytotoxic activity in comparison to the root extracts. The results relate the cytoprotective effect of S. oblonga due to the presence of poly phenols and other phytochemicals, as they have significant ability to remove free radicals or reactive species and might induce the expression of antioxidant enzymes inside the cells.
文摘Background: Traditional plants, their parts, and phytochemicals obtained from them are beneficial for human beings. They are used as potent antimicrobials, but very little research is conducted on the use of traditional medicine against food-borne infection. Different berry plants are rich in phenolic compounds and conventionally known to have many properties such as antioxidants, anti-carcinogenic, anti-inflammatory, anti-bacterial, and anti-diabetics. However, only limited polyphenols are known for their antilisterial effect. The present study aimed to explore the antimicrobial efficacy of phenolic compounds of berries for the treatment of food-borne infection caused by the bacteria Listeria monocytogenes. Materials and Methods: Molecular docking studies employing the Swiss DOCK server were performed to evaluate the antimicrobial activity of phenolic compounds obtained from different varieties of berries. Internalin B(Inl B), a virulence protein of L. monocytogenes was selected as a target. The absorption, distribution, metabolism, excretion, and toxicity profiling of each test ligand was done through the Swiss ADME tool. Results: Among all the test ligands, p-coumaric acid, epicatechins, chlorogenic acid, and quercetin showed better binding efficiency with the target protein Inl B. The binding energy obtained for quercetin, p-coumaric acid, chlorogenic acid, and epicatechins was-8.93,-8.23,-8.18,-7.58, kcal/mol, respectively. Quercetin and p-coumaric acid were forming 4 H-bonds, whereas chlorogenic acid and epicatechins were forming 3-H bonds inside the binding pocket. Conclusion: In a nutshell, analyses indicated that identified ligands have the potential to block the virulent protein Inl B of L. monocytogenes and help combat Listeria infection. These phenolic compounds could be a substitute for synthetic antimicrobials and can be used in food preservation and combat food-borne diseases. However, future in-depth in vitro and in vivo analysis is needed to get more information on these four phenolic ligands of berries.
