Objective: To determinate the recovery of total polyphenolic compounds content,in vitro antioxidant activity and HPLC/ESI/MS characterization of extract from Nephelium lappaceum L.(Mexican rambutan).Methods: The rambu...Objective: To determinate the recovery of total polyphenolic compounds content,in vitro antioxidant activity and HPLC/ESI/MS characterization of extract from Nephelium lappaceum L.(Mexican rambutan).Methods: The rambutan husk extract was obtained by aqueous extraction and a polyphenolic fraction was recovered using Amberlite XAD-16. The total polyphenolic compounds content was determined by the Folin Ciocalteu and butanol-HCI methods.In vitro antioxidant activity was performed using ABTS and ferric reducing antioxidant power methods.Results: Mexican rambutan husk showed a total polyphenolic content of 582 mg/g and an evident antioxidant activity by ABTS and ferric reducing antioxidant power analysis.The HPLC/ESI/MS assay allowed the identification of 13 compounds, most of which belong to ellagitannins. Geraniin, corilagin and ellagic acid were present in the sample;the mineral composition was also evaluated.Conclusions: Rambutan husk cultivated in Mexico is a promising source for the recovery of added value bioactive compounds with antioxidant activity, which have potential applications as bioactive antioxidant agents for the treatment of diseases.展开更多
An experiment on retail film packaging system was conducted to compare the atmospheric composition within sealed packs containing rambutan fruits. This research was done in order to study the effect of packaging films...An experiment on retail film packaging system was conducted to compare the atmospheric composition within sealed packs containing rambutan fruits. This research was done in order to study the effect of packaging films with different permeability on the some of physicochemical properties of rambutan during storage at 10℃. The films used were 0.090 mm low density polyethylene (LDPE), 0.040 mm polyprophylene and 0.057 mm LDPE compared unwrapped fruits. Fruits were evaluated every 5 days for changes in moisture content, total sugars, vitamin C, hardness and color. Unwrapped rambutan had severe browning after 10 days. Sealed packages especially the LDPE had delayed the development of the browning for 20 days of storage and had the lowest weight loss.展开更多
Hierarchically heterostructured hollow spheres are of great interest for a wide range of applications owing to their unique structural features and properties. However, the fabrication of well-defined hollow spheres w...Hierarchically heterostructured hollow spheres are of great interest for a wide range of applications owing to their unique structural features and properties. However, the fabrication of well-defined hollow spheres with highly specific morphology for mixed transition metal oxides on a large scale remains challenging. In this work, uniform rambutan-like heterostructured CeO2~CuO hollow microspheres with numerous copper-ceria interfacial sites and nanorods and nanoparticles as building blocks are prepared via a facile hydrothermal method followed by calcination. Importantly, this approach can be readily scaled up and is applicable to the synthesis of various CuO-based mixed metal oxide complex hollow spheres. The as-prepared CeO2-CuO hollow rambutans exhibit superior performance both as electrode materials for supercapacitors and as Cu-based catalysts for the Rochow reaction, mainly due to the small primary nanoparticle constituents, high surface area, and formation of numerous interior heterostructures.展开更多
以"保研-7号"红毛丹为供试水果,测定3种精油(芥末精油、丁香精油、诺丽精油)处理对其常温保鲜的效果,在筛选适宜浓度基础上,探讨各精油适宜处理水平对红毛丹果实品质的影响。结果表明:基于褐变抑制效果和药害发生,明确芥末精...以"保研-7号"红毛丹为供试水果,测定3种精油(芥末精油、丁香精油、诺丽精油)处理对其常温保鲜的效果,在筛选适宜浓度基础上,探讨各精油适宜处理水平对红毛丹果实品质的影响。结果表明:基于褐变抑制效果和药害发生,明确芥末精油、丁香精油和诺丽精油对采后红毛丹的适宜处理浓度分别为0.004、0.016、0.008 m L/kg。22℃下持续8 d的贮藏期试验结果表明,贮藏结束时,褐变指数依次为诺尼精油>丁香精油>芥末精油;芥末精油在维持果实L值和硬度、丁香精油在维持果实a值和b值、3种精油在维持可溶性固形物含量及膜完整性(相对电导率表示)方面均呈现出良好效果。基于上述3种植物精油对采后红毛丹的保鲜效果及其本身的天然属性,上述植物精油均呈现出一定的应用前景。展开更多
文摘Objective: To determinate the recovery of total polyphenolic compounds content,in vitro antioxidant activity and HPLC/ESI/MS characterization of extract from Nephelium lappaceum L.(Mexican rambutan).Methods: The rambutan husk extract was obtained by aqueous extraction and a polyphenolic fraction was recovered using Amberlite XAD-16. The total polyphenolic compounds content was determined by the Folin Ciocalteu and butanol-HCI methods.In vitro antioxidant activity was performed using ABTS and ferric reducing antioxidant power methods.Results: Mexican rambutan husk showed a total polyphenolic content of 582 mg/g and an evident antioxidant activity by ABTS and ferric reducing antioxidant power analysis.The HPLC/ESI/MS assay allowed the identification of 13 compounds, most of which belong to ellagitannins. Geraniin, corilagin and ellagic acid were present in the sample;the mineral composition was also evaluated.Conclusions: Rambutan husk cultivated in Mexico is a promising source for the recovery of added value bioactive compounds with antioxidant activity, which have potential applications as bioactive antioxidant agents for the treatment of diseases.
文摘An experiment on retail film packaging system was conducted to compare the atmospheric composition within sealed packs containing rambutan fruits. This research was done in order to study the effect of packaging films with different permeability on the some of physicochemical properties of rambutan during storage at 10℃. The films used were 0.090 mm low density polyethylene (LDPE), 0.040 mm polyprophylene and 0.057 mm LDPE compared unwrapped fruits. Fruits were evaluated every 5 days for changes in moisture content, total sugars, vitamin C, hardness and color. Unwrapped rambutan had severe browning after 10 days. Sealed packages especially the LDPE had delayed the development of the browning for 20 days of storage and had the lowest weight loss.
文摘Hierarchically heterostructured hollow spheres are of great interest for a wide range of applications owing to their unique structural features and properties. However, the fabrication of well-defined hollow spheres with highly specific morphology for mixed transition metal oxides on a large scale remains challenging. In this work, uniform rambutan-like heterostructured CeO2~CuO hollow microspheres with numerous copper-ceria interfacial sites and nanorods and nanoparticles as building blocks are prepared via a facile hydrothermal method followed by calcination. Importantly, this approach can be readily scaled up and is applicable to the synthesis of various CuO-based mixed metal oxide complex hollow spheres. The as-prepared CeO2-CuO hollow rambutans exhibit superior performance both as electrode materials for supercapacitors and as Cu-based catalysts for the Rochow reaction, mainly due to the small primary nanoparticle constituents, high surface area, and formation of numerous interior heterostructures.
文摘以"保研-7号"红毛丹为供试水果,测定3种精油(芥末精油、丁香精油、诺丽精油)处理对其常温保鲜的效果,在筛选适宜浓度基础上,探讨各精油适宜处理水平对红毛丹果实品质的影响。结果表明:基于褐变抑制效果和药害发生,明确芥末精油、丁香精油和诺丽精油对采后红毛丹的适宜处理浓度分别为0.004、0.016、0.008 m L/kg。22℃下持续8 d的贮藏期试验结果表明,贮藏结束时,褐变指数依次为诺尼精油>丁香精油>芥末精油;芥末精油在维持果实L值和硬度、丁香精油在维持果实a值和b值、3种精油在维持可溶性固形物含量及膜完整性(相对电导率表示)方面均呈现出良好效果。基于上述3种植物精油对采后红毛丹的保鲜效果及其本身的天然属性,上述植物精油均呈现出一定的应用前景。