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Ganoderic acid A ameliorates renalfibrosis by suppressing the expression of NPC1L1
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作者 TIANYUN HAN ZHONG LI +1 位作者 LUONING ZHANG LINSHEN XIE 《BIOCELL》 SCIE 2024年第11期1625-1638,共14页
Objective: The study aimed to explore the protective mechanism of Ganoderic acid A (GAA) in renal fibrosisand to verify that GAA can ameliorate renal fibrosis by regulating the Niemann-pick C1-like 1 (NPC1L1) gene. Meth... Objective: The study aimed to explore the protective mechanism of Ganoderic acid A (GAA) in renal fibrosisand to verify that GAA can ameliorate renal fibrosis by regulating the Niemann-pick C1-like 1 (NPC1L1) gene. Methods:Transforming growth factor beta1 (TGF-β1) was used to treat Human Kidney-2 (HK-2) cells to establish a renal fibrosismodel. The differentially expressed genes in the control (CTRL) group, TGF-β1 group, and TGF-β1 + GAA group werescreened via transcriptome sequencing technology and verified by qPCR and Western blot experiments. The NPC1L1gene overexpression plasmid was constructed. The expression levels of N-cad, E-cad, and Slug-related proteins inCTRL, TGF-β1, TGF-β1+GAA (25 μg/mL), and TGF-β1+GAA (25 μg/mL) + NPC1L1 Overexpression (OE) groupswere detected by qPCR and Western blot analysis. Western blot analysis was used to identify the extracellular matrixassociated proteins Tenascin-C, α-SMA, and fibrosis-related protein Collagen I. Fibrosis marker protein Fibronectinwas detected and quantified by immunofluorescence. Results: Transcriptomic sequencing revealed that TGF-β1stimulation led to 267 differentially regulated genes, with 118 up-regulated and 149 down-regulated, while furthermodulation of 213 genes, comprising 112 up-regulated and 101 down-regulated genes, was observed in the GAAintervention group. The target gene in these processes was found to be NPC1L1 by investigations using GeneOntology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG). qPCR and Western blot resultsconfirmed that TGF-β1 increased NPC1L1 expression, which was attenuated by GAA. Additionally, TGF-β1upregulated N-cad and Slug. However, GAA reversed this effect and NPC1L1 overexpression partially rescued theGAA effect. TGF-β1 also decreased E-cad expression, reversed by GAA, and NPC1L1 overexpression antagonized thisreversal. Furthermore, TGF-β1 promoted Collagen I, α-SMA, and Tenascin-C expression, and GAA reduced theselevels, effects that were reversed by NPC1L1 overexpression. Immunofluorescence results showed that TGF-β1increased fibronectin expression, which was decreased by GAA, and increased by NPC1L1 overexpression.Conclusion: GAA ameliorates renal fibrosis by antagonizing NPC1L1 gene expression inhibiting epithelialmesenchymal transition and reducing extracellular matrix formation. 展开更多
关键词 Ganoderic acid A NPC1l1 Epithelial-mesenchymal transition Renalfibrosis TRANSCRIPTOMICS TGF-Β
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Development of a Freeze-Dried Skin Care Product Composed of Hyaluronic Acid and Poly(γ-Glutamic Acid) Containing Bioactive Components for Application after Chemical Peels 被引量:3
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作者 Yuka Isago Ryusuke Suzuki +2 位作者 Eri Isono Yuya Noguchi Yoshimitsu Kuroyanagi 《Open Journal of Regenerative Medicine》 2014年第3期45-53,共9页
Eight types of spongy sheet were prepared by freeze-drying aqueous solutions of hyaluronic acid (HA) and poly(γ-glutamic acid) (PGA) with or without bioactive components including vitamin C derivative (VC), glucosylc... Eight types of spongy sheet were prepared by freeze-drying aqueous solutions of hyaluronic acid (HA) and poly(γ-glutamic acid) (PGA) with or without bioactive components including vitamin C derivative (VC), glucosylceramide (GC), and epidermal growth factor (EGF). Spongy sheets were categorized into the following groups: Group I (HA/PGA), Group II (HA/PGA + VC), Group III (HA/PGA + GC), Group IV (HA/PGA + VC, GC), Group V (HA/PGA + EGF), Group VI (HA/PGA + VC, EGF), Group VII (HA/PGA + GC, EGF), and Group VIII (HA/PGA + VC, GC, EGF). In the first experiment, we examined fibroblast proliferation in conditioned medium that had been prepared by immersing each spongy sheet in a conventional culture medium. EGF-incorporating spongy sheets (Groups V-VIII) enhanced fibroblast proliferation more than EGF-free spongy sheets (Groups I-IV). In the second experiment, cytokine production by fibroblasts was evaluated using a wound surface model. This involved elevation of fibroblasts-incorporating collagen gel sheets to the air-liquid interface, on which a spongy sheet (Groups I, IV, V and VIII) was placed and cultured for 1 week. EGF-incorporating spongy sheets (Groups V and VIII) enhanced the production of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) by fibroblasts more than EGF-free spongy sheets (Groups I and IV). The effect of these four types of spongy sheet on wounds was investigated in animal experiments. Chemical peel was performed by contacting 50% trichloroacetic acid (TCA) on the dorsal region of mice, after which a spongy sheet was placed, and the wound condition was then observed in a two-week period. Angiogenesis was facilitated to a greater degree in Group VIII compared with Groups I, IV and V. This finding indicates that Group VIII spongy sheet is a promising aid for skin recovery after chemical peel. 展开更多
关键词 Chemical PEEl Skin Care Product Hyaluronic acid Poly(γ-glutamic acid) Vitamin C Derivative GlUCOSYlCERAMIDE EPIDERMAl Growth Factor
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Preparation and Evaluation of Poly-γ-Glutamic Acid Hydrogel Mixtures with Basic Drugs or Acidic Drugs: Effect on Ease of Swallowing and Taste Masking 被引量:1
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作者 Honami Kojima Saeri Ikegami +6 位作者 Shiho Nakamura Haruka Nishikawa Tamami Haraguchi Miyako Yoshida Minoru Ozeki Ikuo Kawasaki Takahiro Uchida 《Pharmacology & Pharmacy》 2019年第10期427-444,共18页
The purpose of this study was to prepare a poly-γ-glutamic acid hydrogel (PGA gel), to examine its ease of swallowing using texture profile analysis (TPA) and to evaluate its taste-masking effects on basic or acidic ... The purpose of this study was to prepare a poly-γ-glutamic acid hydrogel (PGA gel), to examine its ease of swallowing using texture profile analysis (TPA) and to evaluate its taste-masking effects on basic or acidic drugs using the artificial taste sensor. Using TPA, 0.5% and 1.0% PGA gels, 0.5% and 1.0% agar and 1.0% ι-carrageenan in the absence of drug was examined the hardness, adhesiveness and cohesiveness, ranked according to permission criteria published by the Japanese Consumers Affairs Agency. 0.5% PGA gel and 1.0% agar were classified into grade II. In the taste sensor measurement, the bitterness suppressions by 0.5% PGA gel were larger than that by 1.0% agar in all drugs and the bitterness suppressions of basic drugs in 0.5% PGA gel were more potent than those of acidic drugs in 0.5% PGA gel. 1H-nuclear magnetic resonance spectroscopic analysis was carried out to examine the difference in mechanism of bitterness suppression between basic drugs and acidic drugs mixed with PGA gel. The signals of the proton nearest to the nitrogen atom of basic drugs shifted clearly upfield, suggesting an interaction between the amino group of basic drugs and the carboxyl group of PGA gel. In conclusion, PGA gel is expected to be a useful excipient in formulations contained various drugs, especially basic drugs;it also has advantage for not only increasing ease of swallowing but also masking the bitterness of drugs even though a small amount of a single drug dose might be preferred. 展开更多
关键词 Poly-γ-glutamic acid HYDROGEl BITTERNESS TASTE Sensor
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An Anionic Polymer Incorporating Low Amounts of Hydrophobic Residues Is a Multifunctional Surfactant. Part 2: Emulsification, Moisture Absorption, and Moisture Retention of Alkyl Esterified Poly-γ-Glutamic Acid
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作者 Makoto Urai Tomoko Aizawa +1 位作者 Mutsuyasu Nakajima Michio Sunairi 《Advances in Chemical Engineering and Science》 2015年第2期181-191,共11页
In the accompanying paper (Part 1), we showed that the fatty acid moiety and the acidity of the polysaccharide-backbone of a fatty acid-containing polysaccharide might be involved in its emul-sification, moisture abso... In the accompanying paper (Part 1), we showed that the fatty acid moiety and the acidity of the polysaccharide-backbone of a fatty acid-containing polysaccharide might be involved in its emul-sification, moisture absorption, and moisture retention abilities. In this study, we synthesized alkyl esterified poly-γ-glutamic acid (PGA) with various chain lengths and degrees of substitution of the alkyl moieties to examine how hydrophobic groups incorporated in the anionic polymer contribute to enhanced emulsification, moisture absorption, and moisture retention. With a low degree of alkylation of PGA, these abilities were drastically improved. To improve the moisture absorption of PGA, alkylation with a short chain length is effective in forming interspaces between PGA chains to trap water molecules. Hydrophobic-hydrophilic balance may also be important to improve the emulsification and moisture retention abilities of PGA alkylates. To the best of our knowledge, this is the first report of the relationship between the structure and the multifunctional abilities of an anionic polymer incorporated with a small amount of hydrophobic residue. PGA alkylates, as well as fatty acid-containing polysaccharides, have potential use as multifunctional surfactants throughout various industries. 展开更多
关键词 Poly-γ-glutamic acid (PGA) AlKYl ESTER EMUlSIFICATION MOISTURE Absorption MOISTURE Retention
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Synthesis,Crystal Structure and Luminescent Properties of a Novel Zinc(II) Complex of N-Acetyl-L-glutamic Acid and Imidazole Ligands
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作者 CHENG Meng-Qi MA Lu-Fang +1 位作者 WANG Li-Ya WANG Jian-Ge 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第11期1375-1379,共5页
A novel complex [Zn(Im)2(A-glu)]-0.5H2O(Im = imidazole, A-glu = N-acetyi- L-glutamic acid) has been synthesized from the reaction of A-glu with Zn(CH3COO)2·2H20 in the presence of Im at 65 ℃, and structu... A novel complex [Zn(Im)2(A-glu)]-0.5H2O(Im = imidazole, A-glu = N-acetyi- L-glutamic acid) has been synthesized from the reaction of A-glu with Zn(CH3COO)2·2H20 in the presence of Im at 65 ℃, and structurally characterized by single-crystal X-ray diffraction. The complex crystallizes in tetragonai, space group P43212 with a = b = 8.9078(6), c = 43.458(6) A, C26H36N10O11Zn2, Mr = 795.39, V= 3448.3(6) A^3, De = 1.532 g/cm^3, Z = 4,μ(MoKα) = 1.461 mm^-1, F(000) = 1640, the final R = 0.0453 and wR = 0.0992. X-ray analysis reveals that the crystal structure is constructed by mixed iigands. A-glu adopts the bis-monodentate coordination mode linking two adjacent metal ions to form a one-dimensional chain. Zinc(Ⅱ) ions are four-coordinated with a distorted tetrahedral geometry. Luminescent properties of the complex have been inves- tigated. 展开更多
关键词 crystal structure N-acetyl-l-glutamic acid Zn(Ⅱ) complex luminescent properties
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Combretastatin A4/poly(L-glutamic acid)-graft-PEG conjugates self-assembled to nanoparticles
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作者 Yang Ou Zhao-hui Tang +4 位作者 Lu Sun Hai-yang Yu Jia Li Mei-hui Zhao Hui Xu 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2018年第2期191-196,共6页
Combretastatin A4(CA4) possesses varying ability to cause vascular disruption in tumors,while the short half-life, low water solubility and deactivation of many CA4 analogs during storage limited its antitumor efficac... Combretastatin A4(CA4) possesses varying ability to cause vascular disruption in tumors,while the short half-life, low water solubility and deactivation of many CA4 analogs during storage limited its antitumor efficacy and drug stability. A novel macromolecular conjugate of CA4(CA4-PL) was synthesized by covalent bonding of CA4 onto poly(L-glutamic acid)-graft-polyethylene glycol(PLG-g-PEG) via Yamaguchi reaction. The obtained CA4-PL was characterized by ~1H NMR, GPC, and UV methods, and the properties of the nanoparticles composed of CA4-PL, including critical aggregation concentration, size and size distribution, and morphology, were investigated. CA4-PL can self-assemble to form micelle-like nanoparticles of 80~120 nm in diameter, which may have potential to improve the blood circulation period as well as the targetability of CA4, and find applications to treat various tumors when combined with traditional chemotherapy or radio therapy. 展开更多
关键词 COMBRETASTATIN A4 Macromolecular conjugate Poly(l-glutamic acid)-graft-polyethylene glycol SElF-ASSEMBlE NANOPARTIClES
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HPLC法同时测定杠板归不同部位中5种成分的含量
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作者 胡冬青 阎兆君 《山西医科大学学报》 CAS 2024年第1期108-112,共5页
目的建立高效液相色谱法同时测定杠板归不同部位(茎、叶、根)中5种成分的含量。方法采用Luna?-C18(4.6 mm×250 mm,5μm)色谱柱,以乙腈-0.1%磷酸水为流动相梯度洗脱,流速为1.0 mL/min,检测波长为320 nm,柱温为30℃,测定杠板归不同... 目的建立高效液相色谱法同时测定杠板归不同部位(茎、叶、根)中5种成分的含量。方法采用Luna?-C18(4.6 mm×250 mm,5μm)色谱柱,以乙腈-0.1%磷酸水为流动相梯度洗脱,流速为1.0 mL/min,检测波长为320 nm,柱温为30℃,测定杠板归不同部位中绿原酸、咖啡酸、芦丁、阿魏酸、槲皮素的含量。结果绿原酸、咖啡酸、芦丁、阿魏酸、槲皮素分别在0.046~4.6μg/mL,0.212~21.2μg/mL,0.055~5.5μg/mL,0.084~8.4μg/mL,0.114~11.4μg/mL范围内质量浓度与峰面积呈线性关系良好(r>0.9990),平均加样回收率为97.65%~102.09%,RSD为1.76%~2.44%。不同部位中5种成分含量差异较大,绿原酸和咖啡酸2个成分在叶中含量高,且远远高于根和茎中的含量;芦丁和阿魏酸主要存在于茎和根中,叶中未检测到;槲皮素在茎中含量最高,叶中次之,根中最低。结论建立的HPLC方法准确可靠、重复性好、专属性强,可用于杠板归不同部位中5个成分含量的同时测定。 展开更多
关键词 高效液相色谱 杠板归 绿原酸 咖啡酸 芦丁 阿魏酸 槲皮素 含量测定
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湿法热解法制备L-焦谷氨酸的工艺优化研究
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作者 王艳领 田春美 《化工管理》 2024年第14期150-152,共3页
采用湿法热解法,以L-谷氨酸为原料,探究L-焦谷氨酸的制备工艺条件。通过单因素和正交试验对反应的条件进行优化,确定了制备L-焦谷氨酸的最佳工艺条件是反应时间4 h、加水量15 g、反应温度150℃,此时所得L-谷氨酸的转化率为97.37%。这种... 采用湿法热解法,以L-谷氨酸为原料,探究L-焦谷氨酸的制备工艺条件。通过单因素和正交试验对反应的条件进行优化,确定了制备L-焦谷氨酸的最佳工艺条件是反应时间4 h、加水量15 g、反应温度150℃,此时所得L-谷氨酸的转化率为97.37%。这种方法是用水作为反应载体,无需催化剂与压力等条件,既节能减排,又产量高,为清洁高效生产L-焦谷氨酸提供了一定的理论指导和实验数据参考。 展开更多
关键词 l-焦谷氨酸 l-谷氨酸 湿法热解 工艺优化
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基于纳米银/聚L-谷氨酸修饰玻碳电极的电化学传感器用于泡菜中亚硝酸钠含量的测定
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作者 黄宝美 左岳瑶 +5 位作者 李媛 浦贤翠 贾悦 钟欣恒 余杰 代钰敏 《理化检验(化学分册)》 CAS CSCD 北大核心 2024年第5期502-506,共5页
采用电沉积和电聚合的方式,将纳米银和L-谷氨酸修饰在玻碳电极上,制得纳米银/聚L-谷氨酸修饰玻碳电极(Poly-L-Glu/Nano-Ag/GCE)。以0.2 mol·L^(-1)磷酸盐缓冲溶液(pH 7.0)为支持电解质,以Poly-L-Glu/Nano-Ag/GCE为工作电极,饱和甘... 采用电沉积和电聚合的方式,将纳米银和L-谷氨酸修饰在玻碳电极上,制得纳米银/聚L-谷氨酸修饰玻碳电极(Poly-L-Glu/Nano-Ag/GCE)。以0.2 mol·L^(-1)磷酸盐缓冲溶液(pH 7.0)为支持电解质,以Poly-L-Glu/Nano-Ag/GCE为工作电极,饱和甘汞电极为参比电极,铂电极为辅助电极,在最佳检测条件下,采用循环伏安法进行测定。结果表明:Poly-L-Glu/Nano-Ag/GCE对亚硝酸钠具有较好的选择性,亚硝酸钠的浓度在4.14×10^(-6)~1.35×10^(-3) mol·L^(-1)内与对应的氧化峰电流的绝对值呈线性关系,检出限(3s/k)为4.14×10^(-7) mol·L^(-1),并且该电极的制备方法具有较好的重复性。将PolyL-Glu/Nano-Ag/GCE用于泡菜样品中亚硝酸钠的测定,检出量为1.33×10^(-5) mol·L^(-1),加标回收率为98.9%~103%。 展开更多
关键词 纳米银 l-谷氨酸 亚硝酸钠 修饰电极 电化学传感器
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复方氨基酸注射液中有关物质N,N′-二乙酰-L-胱氨酸测定
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作者 祝艺娟 罗倩倩 +2 位作者 方海顺 杜碧莹 苏广海 《中国药品标准》 CAS 2024年第3期273-276,共4页
目的:建立测定复方氨基酸注射液中乙酰半胱氨酸有关物质N,N′-二乙酰-L-胱氨酸含量的高效液相色谱法。方法:采用Atlantis dC_(18)色谱柱(4.6 mm×150 mm,3μm),以甲酸铵溶液(取甲酸铵315 mg,加水960 mL溶解,摇匀)-乙腈-甲酸(970∶30... 目的:建立测定复方氨基酸注射液中乙酰半胱氨酸有关物质N,N′-二乙酰-L-胱氨酸含量的高效液相色谱法。方法:采用Atlantis dC_(18)色谱柱(4.6 mm×150 mm,3μm),以甲酸铵溶液(取甲酸铵315 mg,加水960 mL溶解,摇匀)-乙腈-甲酸(970∶30∶1)为流动相,流速为0.7 mL·min^(-1),检测波长为210 nm。结果:N,N′-二乙酰-L-胱氨酸浓度在2.697~53.94μg·mL^(-1)范围内线性关系良好(r=0.9999),检测限和定量限分别为1.4μg·mL^(-1)和4.4μg·mL^(-1),平均回收率为100.2%,RSD为0.5%。结论:经方法学验证,证明本法适用于复方氨基酸注射液中N,N′-二乙酰-L-胱氨酸的含量测定。 展开更多
关键词 高效液相色谱法 复方氨基酸注射液 N N′-二乙酰-l-胱氨酸 有关物质
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L-抗坏血酸联合超声处理对鲜切芋艿贮藏品质的影响 被引量:2
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作者 陈琳 胡兴成 +4 位作者 罗紫玮 王冕 涂晓媛 陈炳智 江玉姬 《食品科学》 EI CAS CSCD 北大核心 2024年第11期267-277,共11页
为探究L-抗坏血酸(L-ascorbic acid,AA)联合超声(ultrasound,US)(AS)处理对鲜切芋艿片贮藏品质的影响,本实验以永定六月红芋为材料,采用质量分数为2%的AA溶液浸泡15 min后,进行US(53 kHz、400 W、10 min)处理,测定贮藏期间鲜切芋艿感官... 为探究L-抗坏血酸(L-ascorbic acid,AA)联合超声(ultrasound,US)(AS)处理对鲜切芋艿片贮藏品质的影响,本实验以永定六月红芋为材料,采用质量分数为2%的AA溶液浸泡15 min后,进行US(53 kHz、400 W、10 min)处理,测定贮藏期间鲜切芋艿感官品质及褐变相关酶等指标。结果表明:与对照组相比,AS处理可以降低鲜切芋艿的失水率,维持较高的硬度,延缓褐变指数升高,降低细胞膜通透性,抑制丙二醛含量累积,抑制表面微生物繁殖,从而维持鲜切芋艿较高的感官品质;与对照组相比,贮藏期间AS处理组还能维持较高的过氧化氢酶、超氧化物歧化酶活性,降低过氧化物酶、多酚氧化酶和苯丙氨酸解氨酶活性,抑制酚类物质消耗速率,并减缓淀粉、可溶性蛋白、可溶性固形物等营养物质的流失速率,抑制可溶性醌的积累,延缓风味劣变。上述结果表明,AS处理能够保持鲜切芋艿较好的贮藏品质。 展开更多
关键词 鲜切芋艿 l-抗坏血酸 超声处理 褐变 贮藏品质
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一株产L-苹果酸黑曲霉菌株的诱变筛选及发酵培养基优化 被引量:1
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作者 刘书彤 石冰冰 +4 位作者 谭奕阳 厉成伟 魏彩霞 王德培 薛鲜丽 《食品工业科技》 CAS 北大核心 2024年第8期165-173,共9页
为筛选一株产L-苹果酸能力强的黑曲霉菌株,通过紫外诱变与高浓度放线菌酮迭代诱变的方法,将野生型菌株诱变为一株产L-苹果酸能力强的黑曲霉菌株,并对其种子或发酵培养基成分进行优化。结果表明,诱变所得一株产L-苹果酸能力强的黑曲霉CGM... 为筛选一株产L-苹果酸能力强的黑曲霉菌株,通过紫外诱变与高浓度放线菌酮迭代诱变的方法,将野生型菌株诱变为一株产L-苹果酸能力强的黑曲霉菌株,并对其种子或发酵培养基成分进行优化。结果表明,诱变所得一株产L-苹果酸能力强的黑曲霉CGMCC NO.40550菌株,其摇瓶发酵时种子培养基最适葡萄糖浓度为60 g/L、最适氮源为(NH_4)_2SO_4 4.95 g/L,黑曲霉菌球形成最优转速220 r/min;发酵培养基最适葡萄糖和最适(NH_4)_2SO_4浓度分别为180 g/L和4.95 g/L,Cu SO_4·5H_2O为其生产苹果酸最佳微量元素,最适添加量为0.065 g/L。通过单因素实验的优化,优化后的培养基更有利于L-苹果酸的合成,发酵96 h时L-苹果酸产酸量达到18.15 g/L,显著提高了245%,L-苹果酸占总酸的百分比达到71.69%。本研究为L-苹果酸的工业化生产奠定基础。 展开更多
关键词 黑曲霉 紫外诱变 l-苹果酸 摇瓶发酵 培养条件
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2-O-α-D-葡萄糖基-L-抗坏血酸的酶法合成及其应用研究进展
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作者 项蓉 王丹芸 +6 位作者 娄婷婷 吴子健 张宏宇 王素英 赵彦巧 张得光 马兴 《食品研究与开发》 CAS 2024年第1期201-210,共10页
2-O-α-D-葡萄糖基-L-抗坏血酸(2-O-D-glucopyranosyl-L-ascorbic acid,AA-2G)不仅稳定性强且保留了L-抗坏血酸(L-ascorbic acid,L-AA)的大部分生理活性,是L-AA最好的替代品。体外酶法合成AA-2G具有经济、快速、绿色和安全等显著优势,... 2-O-α-D-葡萄糖基-L-抗坏血酸(2-O-D-glucopyranosyl-L-ascorbic acid,AA-2G)不仅稳定性强且保留了L-抗坏血酸(L-ascorbic acid,L-AA)的大部分生理活性,是L-AA最好的替代品。体外酶法合成AA-2G具有经济、快速、绿色和安全等显著优势,是规模化生产AA-2G的可行方法。该文综述体外酶法合成AA-2G的研究进展,重点梳理环糊精糖基转移酶和蔗糖磷酸化酶合成AA-2G的研究现状,并对AA-2G的功能及应用前景进行讨论和展望。 展开更多
关键词 l-抗坏血酸 2-O-α-D-葡萄糖基-l-抗坏血酸 酶法合成 糖基转移酶 功能
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构建大肠杆菌合成生物群落利用混合糖同步发酵生产L-乳酸
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作者 邱炜玥 李敏 +3 位作者 陈思宇 赵锦芳 王金华 赵筱 《中国食品学报》 EI CAS CSCD 北大核心 2024年第7期208-218,共11页
目的:实现大肠杆菌混合糖发酵产L-乳酸过程中对葡萄糖-木糖的同步利用。方法:以L-乳酸工程菌大肠杆菌JH16(E.coli B,△frdBC△pflB△ackA△adhE,ldhA::ldhL)为出发菌株,通过RED同源重组技术敲除木糖转运及代谢基因xylFGH、xylE和xylA,... 目的:实现大肠杆菌混合糖发酵产L-乳酸过程中对葡萄糖-木糖的同步利用。方法:以L-乳酸工程菌大肠杆菌JH16(E.coli B,△frdBC△pflB△ackA△adhE,ldhA::ldhL)为出发菌株,通过RED同源重组技术敲除木糖转运及代谢基因xylFGH、xylE和xylA,获得不能利用木糖的菌株大肠杆菌JH16031。以大肠杆菌JH2705(E.coli JH16,△ptsG△mglB)为出发菌株,敲除葡萄糖转运及代谢基因crr、malX和galP,获得不能利用葡萄糖的菌株大肠杆菌JH27071,以构建大肠杆菌合成生物群落。通过摇瓶和5 L发酵罐试验确定该合成生物群落在混合糖发酵时较优的混合接种比例。结果:以60 g/L葡萄糖和40 g/L木糖为碳源进行发酵,当JH16031与JH27071初始接种比为1∶50,初始OD_(600nm)=0.5,混合糖的利用率最高,在84 h内消耗97%的糖,并在96 h内结束发酵。葡萄糖消耗速率为705 mg/(L·h),木糖消耗速率为435 mg/(L·h),L-乳酸产率为951 mg/(L·h),L-乳酸产量达到92 g/L,糖酸转化率为91%。结论:构建大肠杆菌合成生物群落可实现利用混合糖发酵产L-乳酸过程中葡萄糖和木糖的同步利用。研究结果为工业发酵生产中,使用低成本的木质纤维素为原料,降低发酵成本,提高混合糖利用率提供技术支持。 展开更多
关键词 大肠杆菌 合成生物群落 混合糖 l-乳酸
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Flavonoids and Amino Acids Analysis of the Fruits of Cornus mas L. Introduced in Uzbekistan
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作者 Gulnaz Matkarimova Nodira Nurullayeva Khislat Khaydarov 《American Journal of Plant Sciences》 2023年第9期1075-1084,共10页
Cornelian cherry is used in the food and pharmaceutical industry as an ornament, in traditional medicine, and in the manufacture of household items.  It is widely used in medicine for the prevention and treatment... Cornelian cherry is used in the food and pharmaceutical industry as an ornament, in traditional medicine, and in the manufacture of household items.  It is widely used in medicine for the prevention and treatment of many diseases. Therefore, it is important to research the chemical composition of these species. In the article, based on our research, the analysis of the quantitative calculation of flavonoids and amino acids of the fruits of the “Elegant” and “Svetlyachok” cherry varieties was carried out. It was found that the amount of amino acids in the fruits of Cornus mas L., introduced in Uzbekistan, is higher in the variety “Svetlyachok” 2.643235 mg/g. In “Elegant” variety it was 1.794235 mg/g. The amount of 4 different flavonoids in the fruit was also determined. It has been established that the Elegant variety has a high concentration of lutein and rutin, and the svetlyachok has a high concentration of apigenin and quercetin. 展开更多
关键词 Cornus mas l. MEDICINAl Amino acid Composition FlAVONOIDS FRUITS
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Physiological Responses of Pea Plants to Salinity and Gibberellic Acid
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作者 Houneida Attia 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第1期149-164,共16页
Pea is a seed legume.It is rich in cellulose fibre and protein.It is also a significant source of minerals and vitamins.In this paper,we set out to better characterize the physiological responses of Pisum sativum L.to... Pea is a seed legume.It is rich in cellulose fibre and protein.It is also a significant source of minerals and vitamins.In this paper,we set out to better characterize the physiological responses of Pisum sativum L.to the combined effects of NaCl,100 mM and gibberellins(GA3).Our analysis revealed that NaCl caused a decrease in growth resulting in a reduction in root elongation,distribution and density,leaf number and leaf area,and a decrease in dry matter of roots and shoots.However,the contribution of GA3 in the salty environment induced an increase in these different parameters suggesting an improving effect of this hormone on growth of pea in presence of salt.NaCl also led to a disturbance of the photosynthetic machinery.Indeed,level of chlorophyll pigments(a and total)and photosynthetic activity were decreased compared to the control plants.However,the exogenous supply of GA3 restored this decrease in net CO_(2) assimilation,but not in chlorophyll content.Additional analyses were performed on the effect of salinity/GA3 interaction on osmolytes(soluble sugars and starch).Our results showed an increase in sugars and a decrease in starch in the presence of 100 mM NaCl.The salt-GA3 combination resulted in compensation of soluble sugar contents but not of starch contents,suggesting a beneficial effect of GA3 under saline stress conditions.Level of three main polyamines putrescine,spermidine,and spermine increased significantly in all organs of salt-treated plants. 展开更多
关键词 Pisum sativum l. SAlINITY gibberellic acid GROWTH sugars polyamines
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Identification and expression analysis of chlorogenic acid biosynthesis key gene PpHCT in peach
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作者 Ziwen Su Meng Sun +7 位作者 Zhixiang Cai Shaolei Guo Jiyao Li Bintao Zhao Zhijun Shen Ruijuan Ma Juan Yan Mingliang Yu 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第4期670-680,共11页
Shikimic acid/quinic acid hydroxy cinnamyl transferase(HCT)is one of the key enzymes in the phenylpropanoid pathway.However,the role of the HCT gene in chlorogenic acid(CGA)biosynthesis in peach fruit remains unclear.... Shikimic acid/quinic acid hydroxy cinnamyl transferase(HCT)is one of the key enzymes in the phenylpropanoid pathway.However,the role of the HCT gene in chlorogenic acid(CGA)biosynthesis in peach fruit remains unclear.For this,we identified the accumulation pattern of CGA in four peach cultivars,cloned and characterized 11 PpHCT gene members,and further analyzed the expression patterns of these PpHCT genes during fruit development.The contents of CGAs in the four peach cultivars all exhibited a trend of increasing and then decreasing during the fruit growth and development.Moreover,the contents of CGAs in the peel and flesh were tissue-specific.Gene structure analysis indicated that the PpHCT genes were highly conserved,containing two exons and one intron.The protein structure analysis demonstrated that the PpHCT proteins contained two conserved motifs(HXXXD,DFGWG)and a transferase domain(PF02458),which belonged to the BAHD acyltransferase family.The cis-acting element analysis suggested that the promoters of PpHCT genes contained many light-related,hormone-related,stress-related,tissue-specific,and circadian-related elements,and they could participate in a variety of biological processes.Phylogenetic analysis showed that the HCT proteins of peach were closely related to the HCT proteins of plum and had a close evolutionary relationship.The qRT-PCR analysis indicated that the expression levels of PpHCT1 and PpHCT2 showed an opposite trend to the accumulation of CGA,whereas the expression levels of PpHCT4,PpHCT5,PpHCT7,PpHCT8,and PpHCT11 demonstrated the same trend as CGA accumulation.It was worth noting that only PpHCT4 and PpHCT5 were highly expressed in the two high-CGA cultivars but showed low levels of expression in the two low-CGA cultivars.Therefore,it was hypothesized that these two genes might be key genes to the synthesis of CGA in peach fruit.Those findings provide a theoretical basis for further study on the biological functions of the HCT gene and help to reveal the molecular mechanism of CGA. 展开更多
关键词 Prunus persica(l.) Chlorogenic acid PpHCT Bioinformatics analysis Gene expression
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Silencing of the Nonspecific Phospholipase C6(NPC6)Gene Induces Ricinoleic Acid Accumulation in Castor Seeds
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作者 Yong Zhao Lili Li +7 位作者 Rui Luo Mu Peng Tongtong Jiang Mingda Yin Yanpeng Wen Zihan Wang Fenglan Huang Fanjuan Meng 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第12期3237-3250,共14页
Castor,scientifically known as Ricinus communis L.,is among the top ten oil crops globally.It is considered a renewable resource and is commonly referred to as‘green oil’.Castor seeds contain castor oil as their mai... Castor,scientifically known as Ricinus communis L.,is among the top ten oil crops globally.It is considered a renewable resource and is commonly referred to as‘green oil’.Castor seeds contain castor oil as their main component,which is predominantly composed of ricinoleic acid.This study utilized RNAi technology to silence the NPC6 gene in NO.2129 castor,resulting in the creation of mutant plants L1 and L2.The weight of 100 dry seed kernels from L1 and L2 exceeds that from NO.2129.The crude fat and ricinoleic acid levels of L1 and L2 were higher than those of NO.2129 at various developmental stages.In the proteomics analysis of 60-day-old castor seeds,a total of 21 differentially expressed proteins were identified,out of which 19 were successfully recognized.Eleven of the differentially expressed proteins identified were legumins,which play a crucial role in nutrient storage within the seed.Silencing the NPC6 gene results in the accumulation of ricinoleic acid in castor seeds.The findings of this study not only enhance our knowledge of NPC6’s role in regulating castor seed oil synthesis but also offer fresh perspectives for investigating oil synthesis and accumulation in other plant species. 展开更多
关键词 Ricinus communis l ricinoleic acid NPC6 RNAI
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强化厌氧表达dld基因以提高大肠杆菌工程菌发酵产L-乳酸的光学纯度
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作者 余杰 李正 +3 位作者 王金华 王永泽 高娃 赵筱 《中国酿造》 CAS 北大核心 2024年第8期115-121,共7页
为去除廉价发酵原料中的D-乳酸从而提高发酵最终产物L-乳酸的光学纯度,该研究通过构建带有不同厌氧诱导启动子(pflBp6、pnirB、pflBp6-pnirB)的D-乳酸脱氢酶基因(dld)的表达质粒,并将其分别转入大肠杆菌(Escherichia coli)HBUT-L,加强... 为去除廉价发酵原料中的D-乳酸从而提高发酵最终产物L-乳酸的光学纯度,该研究通过构建带有不同厌氧诱导启动子(pflBp6、pnirB、pflBp6-pnirB)的D-乳酸脱氢酶基因(dld)的表达质粒,并将其分别转入大肠杆菌(Escherichia coli)HBUT-L,加强其在发酵产L-乳酸的同时消除外源D-乳酸的能力。通过装液量与转速的单因素试验筛选最优的质粒表达条件及菌株,并在无机盐培养基与玉米浆培养基中进行发酵验证。结果表明,在装液量为200 mL/250 mL、转速为150 r/min的条件下,含有启动子pflBp6-pnirB的表达质粒的工程菌株HBUT-L4发酵18 h时D-乳酸脱氢酶活力最高,为81.1 U/g。在此条件下进行无机盐培养基和玉米浆培养基发酵时,工程菌株HBUT-L4相对于出发菌株HBUT-L,D-乳酸消耗速率分别提高250%、217%,L-乳酸的光学纯度分别从96.32%、98.48%提升至99.95%、99.98%。在大肠杆菌工程菌发酵L-乳酸的过程中,带有厌氧诱导启动子pflBp6-pnirB的表达质粒可提高D-乳酸脱氢酶活力,强化菌株消除外源D-乳酸,进而提高L-乳酸的光学纯度的能力,具有重要的工业化应用价值。 展开更多
关键词 l-乳酸 光学纯度 启动子 D-乳酸脱氢酶基因 大肠杆菌
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Changes and significance of serum ubiquitin carboxyl-terminal hydrolase L1 and glial fibrillary acidic protein in patients with glioma
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作者 Qing-Hua Zhu Jing-Kun Wu Gao-Lei Hou 《World Journal of Clinical Cases》 SCIE 2023年第14期3158-3166,共9页
BACKGROUND Brain gliomas are malignant tumors with high postoperative recurrence rates.Early prediction of prognosis using specific indicators is of great significance.AIM To assess changes in ubiquitin carboxy-termin... BACKGROUND Brain gliomas are malignant tumors with high postoperative recurrence rates.Early prediction of prognosis using specific indicators is of great significance.AIM To assess changes in ubiquitin carboxy-terminal hydrolase L1(UCH-L1)and glial fibrillary acidic protein(GFAP)levels in patients with glioma pre-and postoperatively.METHODS Between June 2018 and June 2021,91 patients with gliomas who underwent surgery at our hospital were enrolled in the glioma group.Sixty healthy volunteers were included in the control group.Serum UCH-L1 and GFAP levels were measured in peripheral blood collected from patients with glioma before and 3 d after surgery.UCH-L1 and GFAP levels in patients with glioma with different clinicopathological characteristics were compared before and after surgery.The patients were followed-up until February 2022.Postoperative glioma recurrence was recorded to determine the serum UCH-L1 and GFAP levels,which could assist in predicting postoperative glioma recurrence.RESULTS UCH-L1 and GFAP levels in patients with glioma decreased significantly 3 d after surgery compared to those before therapy(P<0.05).However,UCH-L1 and GFAP levels in the glioma group were significantly higher than those in the control group before and after surgery(P<0.05).There were no statistically significant differences in preoperative serum UCH-L1 and GFAP levels among patients with glioma according to sex,age,pathological type,tumor location,or number of lesions(P>0.05).Serum UCH-L1 and GFAP levels were significantly lower in the patients with WHO grade I-II tumors than in those with gradeⅢ-IV tumors(P<0.05).Serum UCH-L1 and GFAP levels were lower in the patients with tumor diameter≤5 cm than in those with diameter>5 cm,in which the differences were statistically significant(P<0.05).Glioma recurred in 22 patients.The preoperative and 3-d postoperative serum UCH-L1 and GFAP levels were significantly higher in the recurrence group than these in the non-recurrence group(P<0.05).Receiver operating characteristic curves were plotted.The areas under the curves of preoperative serum UCH-L1 and GFAP levels for predicting postoperative glioma recurrence were 0.785 and 0.775,respectively.However,the efficacy of serum UCH-L1 and GFAP levels 3 d after surgery in predicting postoperative glioma recurrence was slightly lower compared with their preoperative levels.CONCLUSION UCH-L1 and GFAP efficiently reflected the development and recurrence of gliomas and could be used as potential indicators for the recurrence and prognosis of glioma. 展开更多
关键词 GlIOMA Ubiquitin carboxy-terminal hydrolase l1 Glial fibrillary acidic protein Surgery Prognosis Clinical significance
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