Antioxidant activities of mandarin (Citrus unshiu) peel pectin films containing sage (Salvia officinalis) leaf extract

Biopolymer films were prepared using pectin extracted from mandarin peel, a by-product of fruit processing. Varying amounts (0.6%, 1.0% and 1.4%) of sage leaf extract (SLE) were also added to mandarin peel pectin (MPP) films to enhance its antioxidant abilities. Compared with the MPP film alone, the total phenolic contents of the MPP films containing SLE were higher. The MPP film with 0.6% SLE possessed the most desirable physical properties with tensile strength of 23.31 MPa and an elongation at break of 18.82%. We used four different methods to identify the antioxidant property of the MPP films with SLE, and the results showed that the antioxidant activity increased with increase in the amount of SLE added. In contrast, the addition of SLE lowered the thermal stability and water resistance of the MPP film. These results indicate that the developed MPP films containing SLE can be potentially used for food-based applications.     

Antioxidant activities of premature and mature mandarin (Citrus unshiu) peel and juice extracts

Food Science and Biotechnology - In vitro antioxidant activities of premature and mature mandarin peel and juice extracts were investigated for their potentials as functional food materials. Total...     

磨皮取油后橙皮的二次利用对精油品质的影响

为了开发利用工业化生产中磨皮取油后的剩余橙皮,提高橙皮精油得率,以伏令夏橙为研究对象,采用水蒸气蒸馏法分别提取机器磨皮所得油水混合物及磨皮后剩余橙皮的精油,计算两者精油得率并比较成分差异,从橘红和橘白中提取的挥发油作为对照。结果显示,剩余的橙皮回收利用可使橙皮精油得率提高11.55%。GC—MS分析发现油水混合物和剩余橙皮提取的精油成分有较大不同。与油水混合物提取的精油相比,剩余皮精油中的酮类化合物、酯类化合物、醇类化合物和脂肪酸相对含量较高,而烃及其衍生物的相对含量较低。试验表明回收利用磨皮后的剩余橙皮可以提高橙皮精油产量,并具有浓郁的香气。     

不同解冻方法对速冻温州蜜柑橘瓣品质的影响

速冻是一种优良的水果保藏方法,对速冻温州蜜柑橘瓣而言,其适宜的解冻方法仍在探索中。本文对比研究了冰箱缓慢解冻、自然解冻、流水解冻、温水解冻和微波解冻法对速冻温州蜜柑橘瓣品质的影响。结果表明:微波解冻时间较短,汁液流失率为3.89%,VC损失率为12.39%,可滴定酸含量增加了9.52%,对还原糖、可溶性固形物、香气、弹性影响较小,对色泽、硬度、内聚性、胶着性、咀嚼性有显著影响,但只有对a*值的影响要显著大于其他几种解冻方法(p<0.05)。该研究结果表明,微波解冻是一种适合速冻温州蜜柑橘瓣解冻的有效方法。      

Hepatoprotective effect of Handaeri-gomchi (Ligularia fischeri var. spiciformis Nakai) extract against chronic alcohol-induced liver damage in rats

Handaeri-gomchi (Ligularia fischeri var. spiciformis Nakai) (LF) is well known as a medicinal plant in Korea, especially to treat a variety of human disease including hepatic function failure. In this study, we examined the activity of LF extract against the liver injuries and oxidative stress by chronic alcohol in Spargue-Dawley rats. Severe liver damage caused by alcohol intake with increasing activity of hepatic markers was decreased in the group of rats fed LF extract. The results were confirmed through hematoxylin and eosin staining. Antioxidative capacity was decreased by alcohol but it was recovered by LF extract. Elevated indicators of oxidative stress by chronic alcohol were diminished in the group of LF extract. Furthermore, LF extracts increased antioxidative capacity and the activity of antioxidant enzymes. In conclusion, LF extract has a protective effect against chronic alcohol hepatotoxicity, suggesting it could be developed as a functional food or medicine for protection of liver disease.     

Effect of water-soluble propolis administration on the ethanol-induced hangover in rats

Water soluble propolis was prepared using β–cyclodextrin, and its effect on an ethanol-induced hangover was examined in Sprague–Dawley (SD) rats fed with ethanol. When SD rats were administrated with propolis 30 min after ethanol feeding, ethanol content in the rat serum decreased 2.1 times 1 h after ethanol feeding. Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) activity in rat liver increased 3.0 and 4.4 times, respectively, 1 h after ethanol feeding and administration of propolis 30 min after ethanol feeding. There were no differences in the expression of ADH and ALDH genes regardless of propolis administration. These results indicated that a decrease in ethanol content in the serum was not due to an increase in the expression of ADH or ALDH genes but rather, an increase in activities of ADH and ALDH.     

Purification and characterisation of basic ascorbate oxidase from satsuma mandarin (Citrus unshiu Marc)

Basic ascorbate oxidase of the multiple enzyme forms existing in young fruit of satsuma mandarin (Citrus unshiu Marc) has been separated and subsequently purified to electrophoretic homogeneity through (NH₄)₂SO₄ fractionation and chromatographies on DEAE-Toyopearl 650M, CM-Sephadex C-50 and Sephadex G-100. The native molecular weight was estimated to be 141 kDa by gel filtration and composed of two non-identical subunits with an apparent mass of 74 kDa and 62 kDa. The optimum pH was found to be 5.5 with reasonable stability between pH 5 and 8. The enzyme had an optimum temperature at 45°C and was stable up to 50°C upon heat treatment for 5 min. The presence of sodium diethyldithiocarbamate, metabisulphite and potassium cyanide completely inhibited the enzyme activity. Fluoride also inhibited the activity substantially at higher concentrations. Other tnonovalent and divalent metal ions did not have inhibitory effects.     

Hepatoprotective effect of chicory (Chicorium intybus) root extract against orotic acid-induced fatty liver in rats

Effect of chicory root extract (CRE) on the triglyceride metabolism in orotic acid (OA)-fed rats was investigated. Liver weights and hepatic triglyceride concentrations were markedly increased by OA-feeding rats. These results were attributed to the significant increase in the activity of hepatic phosphatidate phosphohydrolase (PAP), diacylglycerol acyltransferase (DGAT), and ratelimiting enzymes for triglyceride synthesis. Supplementation of CRE to OA did significantly reduced the hepatic triglyceride concentrations and DGAT activity without affecting PAP activity. Furthermore, OA treatment was significantly decreased plasma triglyceride (TG) and increased hepatic TG concentrations and reduced microsomal triglyceride transfer protein (MTP) activity without diminishing MTP mRNA expression in rats. However, hepatic TG concentration was significantly decreased and MTP activity was also reduced without diminishing MTP mRNA expression in rats fed simultaneous with OA and CRE diet. The hepatocytes in the OA-feeding rats contained numerous largely fat droplets, but CRE feeding prevented the OA-induced fat accumulation. Present study demonstrates that CRE reduces the liver TG accumulation by reduced DGAT and MTP activities without diminishing MTP mRNA expression by OA administration.     

Green satsuma mandarin orange (Citrus unshiu) extract reduces adiposity and induces uncoupling protein expression in skeletal muscle of obese mice

Food Science and Biotechnology - Increased fat mass, which is induced by the storage of excess nutrients, is considered a causal factor for various metabolic disorders, including insulin...     

浸提对甜橙果皮中黄烷酮和多甲氧基黄酮的影响及其抗氧化活性研究

以甜橙果皮为材料,采用加热浸提法,研究乙醇体积分数、时间、温度、以及料液比等提取参数对黄烷酮和多甲氧基黄酮含量的影响。利用水沉法精制甜橙果皮黄酮提取物,并研究了精制后甜橙总黄酮的体外抗氧化活性。结果表明,甜橙果皮中黄酮类物质主要为黄烷酮和多甲氧基黄酮,不同提取参数下,两者的变化趋势差异明显。其中黄烷酮的最佳提取工艺为:乙醇体积分数70%,料液比为1∶20,90℃提取4 h,达到(24.74±0.42)mg/g;而多甲氧基黄酮提取的最佳条件为:乙醇体积分数80%,料液比为1∶10,60℃提取2 h,可达(2.83±0.08)mg/g。水沉法能够有效地除去糖类、有机酸,脂溶性色素等杂质,可以用于精制甜橙果皮总黄酮提取物,精制后的提取物总黄酮纯度从12.34%提高到42.05%。采用自由基清除(2,2-diphenyl-1-picrylhydrazyl radicals,DPPH)和自由基抗氧化(2,2'-azino-bis(3-ethylbenzthiozoline-6)-sulphonicacid,ABTS)法研究提取物的抗氧化活性,发现抗氧化性与提取物中总黄酮含量呈极显著相关。     

温州蜜柑皮多酚物质的超声提取及抗氧化特性

利用100kHz的超声波辅助提取温州蜜柑皮中的多酚类物质,并以传统的浸泡提取法作为对照与超声辅助提取法进行比较。结果表明,超声辅助提取法比浸泡提取法在低温条件下能更加快速、有效的提取酚酸。研究超声时间、提取温度、超声能量对酚酸含量及抗氧化能力的影响,发现温度对酚酸含量和稳定性的影响最为敏感,温度的增加能有效的提高酚酸含量,但是,当温度升高到40℃,延长超声时间造成酚酸含量的大幅度下降。此外,研究表明总酚含量和抗氧化能力呈现良好的线性关系,15、30、40℃处理后,相关系数R2依次为0.8435、0.8895、0.8622;在不同的超声能量水平下,R2为0.7971,这说明温州蜜柑皮是抗氧化物的丰富来源。研究表明超声辅助提取能有效的增加温州蜜柑皮提取物的酚酸含量和抗氧化能力,应用超声波技术增强温州蜜柑皮提取物的抗氧化能力具有潜在的优势。     

Volatile aroma components and antioxidant activities of the flavedo peel extract of unripe Shiikuwasha (Citrus depressa Hayata)

The flavedo peel extracts of unripe Shiikuwasha (Citrus depressa Hayata) fruits were extracted using steam distillation (SD) or a cold-press (CP) system. Volatile aroma content and composition were determined using gas chromatography (GC) and each compound was identified using gas chromatography-mass spectrophotometry (GC-MS). The major constituents of the extracts were monoterpene hydrocarbons (91.75-93.75%[709.32-809.05 mg/100 g of fresh flavedo peel]) including limonene (43.08-45.13%[341.46-379.81 mg/100 g of fresh flavedo peel]), γ-terpinene (27.88-29.06%[219.90-245.86 mg/100 g of fresh flavedo peel]), and p-cymene (8.13-11.02%[61.47-97.22 mg/100 g of fresh flavedo peel]). The extraction process used was determined to be a decisive factor that affects the composition of key citrus aroma components, as well as the antioxidant activities of the Shiikuwasha fruit. Antioxidant capabilities of the extracts were examined by assay of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and β-carotene bleaching inhibition. The cold-press extraction system may better retain the total phenolic content of the flavedo peel and display superior antioxidant activities, compared to the steam distillation extraction method. PRACTICAL APPLICATION: Shiikuwasha (Citrus depressa Hayata) is a type of small citrus fruit, and has been used as raw material for beverage and food additive productions in Japan. It had a unique aroma composition in which the limonene content of its peels is lower than that of other commonly known citrus peels. The present study detailed the volatile aroma composition, as well as antioxidant capabilities of Shiikuwasha peel extracts of different extraction methods, that are cold-press and steam distillation methods. The results of this study may provide a basis for selection of Shiikuwasha peel extracts in food industry for citrus flavor production.     

Antigenicity and phototoxicity of water-soluble extract from Salacia reticulata (Celastraceae)

The antigenicity and phototoxicity of water-soluble extract from Salacia reticulata (SRE) were examined in guinea pigs. In a study of active systemic anaphylaxis reaction, neither the oral administration group (64 or 320 mg/kg, 5 times/week, 3 weeks) nor the subcutaneous administration group (64 mg/kg, 1 time/week, 3 weeks) exhibited any anaphylactic reaction. Moreover, sensitization with serum obtained from these animals did not induce passive cutaneous anaphylaxis reaction in normal animals. In a phototoxicity study, oral administration of SRE (320 mg/kg) induced neither erythema nor edema. These results suggest that SRE is not antigenic or phototoxic.     

基于声化学效应探究低频超声处理对温州蜜柑汁杀菌及其品质的影响

应用低频超声波(25 k Hz)处理宽皮柑橘(温州蜜柑)汁,考察其对特征微生物菌群(细菌、霉菌、酵母、大肠菌群)的灭活效果,同时分析了低频超声波对橘汁品质的影响。研究结果表明,超声时间、超声温度、超声功率均对杀菌率具有极显著影响(P0.01),超声杀菌处理最佳工艺条件为超声温度50℃,超声时间40 min,超声功率720 W;低频超声处理对橘汁糖酸成分无显著性影响(P0.05),同时橘汁抗坏血酸、总酚,以及抗氧化能力均显著高于巴氏杀菌橘汁(P0.05)。低频超声技术具有提升橘汁品质的潜在作用。     

大蒜、橘皮提取液对麻辣烫汤汁中亚硝酸盐清除作用的研究

主要探讨麻辣烫汤汁中亚硝酸盐的含量,以及大蒜和桔皮对汤汁中亚硝酸盐的清除作用。采集不同来源的麻辣烫样品,使用盐酸萘乙二胺法测定不同来源样品中的亚硝酸盐含量。加入大蒜提取液和橘皮提取液,研究乙醇浓度、反应时间、提取温度和提取液用量等因素对亚硝酸盐清除率的影响。结果表明麻辣烫汤汁中亚硝酸盐的含量为1.18~1.58mg/L。大蒜和橘皮提取液都可清除汤汁中的亚硝酸盐。80℃下制备的大蒜水提液在用量为8m L、与样品反应10min时,对麻辣烫汤汁中亚硝酸盐的清除作用最明显。使用3m L浓度为60%的乙醇在70℃下制备的橘皮提取液,与样品反应25min时,对汤汁中亚硝酸盐的清除作用最明显。     

香蕉皮总黄酮对糖尿病及其并发症的影响

目的:研究香蕉皮总黄酮粗提物降血糖作用。方法:将实验大鼠分成正常对照组、模型对照组、药物组和低、中、高香蕉皮总黄酮剂量组,喂养4周。检测大鼠体质量、血糖、总胆固醇（TC）、甘油三酯（TG）、低密度脂蛋白胆固醇（LDL-C）和高密度脂蛋白胆固醇（HDL-C）的水平。结果:中、高剂量的香蕉皮总黄酮粗提物可显著降低四氧嘧啶诱导的糖尿病大鼠血糖、TC、TG和LDL-C含量（p<0.05）,升高大鼠体质量和HDL-C（p<0.05）。结论:一定剂量的香蕉皮总黄酮提取物具有降血糖作用,并且能改善由糖尿病引起脂代谢紊乱状况。      

香蕉皮总黄酮对糖尿病及其并发症的影响

目的:研究香蕉皮总黄酮粗提物降血糖作用。方法:将实验大鼠分成正常对照组、模型对照组、药物组和低、中、高香蕉皮总黄酮剂量组,喂养4周。检测大鼠体质量、血糖、总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)和高密度脂蛋白胆固醇(HDL-C)的水平。结果:中、高剂量的香蕉皮总黄酮粗提物可显著降低四氧嘧啶诱导的糖尿病大鼠血糖、TC、TG和LDL-C含量(p0.05),升高大鼠体质量和HDL-C(p0.05)。结论:一定剂量的香蕉皮总黄酮提取物具有降血糖作用,并且能改善由糖尿病引起脂代谢紊乱状况。     

Yerba-mate (Ilex paraguariensis) extract prevents ethanol-induced liver injury in rats

Ethanol metabolism-associated oxidative stress contributes to the pathogenesis of alcoholic liver disease. We examined the effect of a Mate tea extract on ethanol-induced liver injury in vitro and in vivo models. Isolated hepatocytes were incubated with ethanol. An extract of Yerba-Mate tea (EMT) was added to the cultures simultaneously with ethanol. EMT treatment suppressed the ethanol-induced increase in cell death by inhibiting cytochrome p450 2E1 (CYP2E1) activity, which is related to the production of reactive oxygen species. Furthermore, we examined the effects of EMT on serum transaminase activity, and the progression of liver fibrosis in rats treated with ethanol and CCl₄. Rats were fed a diet that included 0.005% or 0.02% EMT or no EMT. For a period of 3 weeks, the animals were provided drinking water containing 5% ethanol and were also treated with carbon tetrachloride (CCl₄) (0.1 ml/kg of body weight). EMT treatment suppressed plasma ALT and AST activities in the ethanol- and CCl₄-treated rats. EMT treatment also decreased CYP2E1 expression and increased ADH expression in the ethanol- and CCl₄-treated rats. EMT treatment fully protected the rats against ethanol- and CCl₄-induced liver injury. These results suggest that EMT may serve as a candidate for preventing ethanol-induced liver injury.     

椪柑、温州蜜桔果皮中酚类物质组成及抗氧化能力研究

目的:研究椪柑、温州蜜桔果皮中酚酸与黄烷酮糖苷组成及其抗氧化能力。方法:高效液相法测定椪柑、温州蜜桔果皮中九种酚酸和两种黄烷酮糖苷的组成与含量。用福林酚法、ABTS法和FRAP法对椪柑、温州蜜桔果皮甲醇提取液抗氧化能力进行评价。结果:柑橘果皮中可溶酯化酚酸部分所占比例最大,肉桂酸型酚酸是柑橘皮中的主要酚酸,且主要以酯化形式存在,其含量排列顺序一般为:阿魏酸>对香豆酸>芥子酸>咖啡酸。温州蜜桔果皮中有较高总酚酸含量(p<0.05)。椪柑果皮主要含橙皮苷,温州蜜桔果皮含橙皮苷和少量柚皮芸香苷。温州蜜桔果皮中总黄烷酮糖苷含量高于椪柑(p<0.05)。总的来说椪柑果皮提取液抗氧化活性略高于温州蜜桔。结论:HPLC测定柑橘皮中酚酸与黄烷酮糖苷可取得良好结果,抗氧化实验表明柑橘皮具有一定的抗氧化能力。