Physicochemical characteristics and antioxidant activities of grape Yakju

The physicochemical characteristics and antioxidant activities of grape yakju, a traditional Korean alcoholic beverage, were investigated during the fermentation process. Reducing sugars decreased while total acid content increased throughout fermentation. Alcohol content increased up to 16–20% after the 10^th day of fermentation. The content of total phenolic compounds and flavonoid in yakju increased with fermentation time. Anthocyanin was found only in yakju made from grapes. ‘Muscat Baily A (MBA)’ yakju was the most preferred regarding color, flavor, taste, and overall acceptance. Antioxidant activities of grape yakju, except for the 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity, increased with fermentation time, with the following in the order of increasing antioxidant activity after fermentation: ‘MBA’, ‘Campbell’, ‘Kyoho’, and control yakju. Antioxidant activities of grape yakju depended on total flavonoid content rather than total phenolic compounds.     

桑叶多酚的鉴定及其抗氧化、抗α-淀粉酶活性分析

目的:桑树叶片在传统医学中被用作降糖和降血压的药物,其作用机理与活性成分含量有关。评价桑叶提取物不同生物活性,包括生物活性物质含量、抗氧化活性和抗α-淀粉酶活性。方法:采用SPE（固相萃取技术）将多酚粗提液分离纯化为花色苷、非花色苷多酚和水层三个组分,采用HPLC-PDA和HPLC-ESI/MS2对桑叶中的多酚物质进行系统地定性和定量。利用DPPH（1,1-二苯基-2-三硝基苯肼自由基清除能力）、ABTS（2,2’-联氮-双（3-乙基苯并噻唑啉-6-磺酸））和FRAP（铁离子还原能力）三种方法测定不同提取物的抗氧化活性,并采用福林酚法、pH差异法和比色法测定桑叶提取物总酚、总花色苷和总原花青素含量。结果:桑叶中共鉴定出6种花色苷、42种非花色苷多酚,其中,矮牵牛素-3-葡萄糖苷和原花青素衍生物含量很高;桑叶中总酚、总花色苷和总原花青素的含量分别为14.09 mg GAE/g DW、0.17 mg C3G/g DW和17.24 μg PA2/g DW;多酚粗提液、花色苷、非花色苷多酚和水层对α-淀粉酶活性的IC₅₀（半抑制浓度）分别为8.31、13.70、0.25和12.00 mg/mL,由此看出非花色苷多酚的抗α-淀粉酶活性最高。结论:桑叶具有较强的抗氧化活性,其中花色苷显示出最高的抗氧化活性。这些数据可以为蒙古桑叶用作功能食品提供重要参考。     

蓝莓酵素的体外抗氧化及对秀丽隐杆线虫的氧化应激保护作用

以大兴安岭野生蓝莓为原料,发酵制备蓝莓酵素,研究其发酵过程中总花青素、总酚和总黄酮含量变化,以及体外抗氧化能力变化情况,并以秀丽隐杆线虫为模型,初步探究其抗氧化的相关机制。结果表明:在发酵过程中,总花青素含量呈先上升后下降的变化趋势,于发酵第50 d时,达到了0.52 mg/mL,总酚和总黄酮含量总体呈现上升趋势,均于第300 d时达到最大值2.81、3.17 mg/mL;1, 1-二苯基-2-苦苯肼（1, 1-diphenyl-2-picrylhydrazyl,DPPH）自由基清除能力、还原力、氧自由基吸收能力（oxygen-radical absorbance capacity,ORAC）均呈现先快速增长后趋于平缓的变化趋势。蓝莓酵素能够延长秀丽隐杆线虫寿命,增强其在双氧水刺激下的氧化应激能力,提高超氧化物歧化酶（superoxide dismutase,SOD）、过氧化氢酶（catalase,CAT）和谷胱甘肽过氧化物酶（glutathione peroxidase,GSH-Px）等抗氧化酶的活力,并且降低线虫体内活性氧和丙二醛含量,该结果表明蓝莓酵素可能是通过提高抗氧化酶活力来减缓秀丽隐杆线虫的氧化损伤。     

蓝莓酒发酵过程中酚类物质动态变化及其抗氧化活性研究

以兔眼蓝莓为对象,研究其发酵过程中酚类物质和抗氧化活性的变化。结果表明:蓝莓酒发酵过程中,总酚、总黄酮和花色苷含量以及铁还原力、DPPH自由基清除率和羟自由基清除率呈先增加后减少的趋势;颜色分析显示L*值先增加后减少,后酵阶段波动上升,a*值逐渐上升,后酵期间波动下降,a*值变化正相关于花色苷含量的变化,b*值变化正相关于总酚、总黄酮含量的变化;蓝莓酒发酵过程中p-羟基苯甲酸未检出,香草酸含量显著上升(p0.05),而没食子酸、原儿茶酸、龙胆酸、绿原酸、咖啡酸、丁香酸、p-香豆酸、阿魏酸、芥子酸等9种酚酸含量主发酵期间均显著上升(p0.05),发酵结束时含量均显著下降(p0.05),但显著高于各自初始含量(p0.05),对羟基苯甲酸、对羟基肉桂酸和总酚酸含量均呈先增加后减少的趋势。     

桑葚酒不同发酵阶段品质及抗氧化物质的变化

以桑葚果实为原料,通过测定不同发酵阶段酒液的品质和抗氧化物质指标,分析桑葚酒发酵过程中的物质变化规律。结果表明:主发酵期,酵母活细胞数量、酒精度逐渐增大,糖度、p H和色度、色调逐渐减小,而总酚、总花色苷和抗氧化活性呈先增加后减小;后发酵期,品质指标趋于稳定,总酚和总花色苷含量逐渐减小,而抗氧化能力逐渐增大。说明在发酵过程中,缩短发酵时间有利于酚类物质的保留,延长发酵有利于提高酒液的抗氧化能力,发酵34d时,桑葚酒的抗氧化活力最高。      

Phytochemical properties and antioxidant capacities of commercial raspberry varieties

The antioxidant capacities of 15 commercial raspberry varieties grown in North China were evaluated and their anthocyanin profiles determined by LC–ESI-MS. Total polyphenol content (TPC), total flavonoid content (TFC), total anthocyanin content (TAC) and antioxidant capacities (AOC) of the 15 raspberries were measured, respectively and the results showed that the TPC, TFC and TAC contents of raspberries correlated well with their antioxidant capacities. Raspberries with higher contents of phytochemicals showed higher antioxidant capacity. The results indicated that the 15 raspberry varieties may be divided into three groups according to their anthocyanin component analysis. The first group was made up of Triple Crown, Shawnee, and Navaho varieties with identical anthocyanin profiles and dark red color. The second group included Canby, Bristol and Mac black varieties, which possessed higher TAC/TPC ratio and contribute more to antioxidant capacity and the rest of the varieties were in the third group with lower antioxidant capacities. The higher phytochemical contents and antioxidant activities of raspberry varieties in the second group indicated that their consumption would be more beneficial to health.     

Comparative study on chemical composition,polyphenols, flavonoids,carotenoids and antioxidant activities of various cultivars of sweet potato

Chemical composition, polyphenols, flavonoids, carotenoids and antioxidant activities of twenty-five cultivars of sweet potato were investigated. Starch, crude protein, crude fat, total dietary fibre, reducing sugar and ash contents ranged between 51.88–69.21, 2.36–7.79, 0.24–1.11, 5.02–14.35, 1.07–9.78 and 1.95–4.29 g per 100 g dry weight (DW), respectively. Cultivars of Longshu, Pushu 32 and Qinshu No.7 (Shanxi province) displayed the highest values in total polyphenol contents (9.38, 9.11 and 8.76 mg GAE per g DW, respectively), Huangmeigui showed higher flavonoids content (2.54 mg RE per g DW), Xiangshu presented higher anthocyanin content (1.02 mg per g DW), whereas Pushu 32 had the highest β-carotene content (208.11 μg per g DW). Strong significant positive correlations were presented between antioxidant activities and total polyphenol and flavonoid contents, indicating that polyphenols and flavonoids are essential antioxidants in sweet potatoes. Among all cultivars, Pushu 32 presented the highest grey relational grade (GRG) value (0.7811), suggesting its importance as a healthy diet.     

黑枸杞乳酸菌饮料发酵工艺优化及功能性成分研究

以青海的黑枸杞为主要原料,以植物乳杆菌（Lactobacillus plantarum）为发酵菌种,制备黑枸杞乳酸菌饮料,并采用单因素试验和响应面试验优化其发酵工艺条件。结果表明,最佳发酵工艺条件为固液比1∶25（g∶mL）,植物乳杆菌接种量2.0%,发酵时间6 h,装液量40%。在此最佳条件下,黑枸杞乳酸菌饮料感官评分为9.3分,总糖含量为0.17 mg/mL,总酸含量为1.69 g/L,花青素含量为52.75 mg/L、总黄酮含量为0.07 mg/mL、总酚含量为0.99 mg/mL。     

桑葚、甘蔗糖蜜多酚的成分鉴定及其复配物的抗氧化活性

为探索酚类提取物及其复配物的协同增效作用,以桑葚和甘蔗糖蜜多酚作为研究对象,分别测定其总酚、黄酮含量及酚类组成,基于单一提取物的总酚含量按一定配比制得复配物,评价抗氧化活性。结果表明,桑葚游离多酚（MFP）占桑葚总酚含量的90.3%,为677.62 mg没食子酸当量（Gallic Acid Equivalent,GAE）/100 g,黄酮含量为736.65 mg芦丁当量（Rutinum Equivalent,RE）/100 g,共检测出原儿茶酸、3,4-二羟基苯丙酸、咖啡酸、丁香酸、对香豆酸、阿魏酸、矢车菊素3-O-葡萄糖苷和芦丁8种多酚物质,其中矢车菊素3-O-葡萄糖苷含量占92.6%。甘蔗糖蜜多酚（SMP）总酚含量为339.69 mg GAE/100 g,总黄酮含量为314.61 mg RE/100 g,主要单体包括没食子酸、原儿茶酸、绿原酸、咖啡酸、丁香酸、对香豆酸、阿魏酸、芦丁和表儿茶素9种多酚物质。在0~10 mg/mL的浓度范围内SMP、MFP及其复配物具有良好的抗氧化活性且呈现量效关系。同时,两种复配物的抗氧化活性优于SMP和MFP,其中中效原理计算复配物DPPH自由基清除能力的0.25 IC50、0.5 IC50、0.75 IC50、1 IC50、1.25 IC50、1.5 IC50的联合作用指数CI分别为0.73、0.85、0.94、0.91、0.89和0.90,均小于1,表明桑葚和甘蔗糖蜜多酚复配物具有协同抗氧化作用。     

两种工艺拐枣酒抗氧化成分及活性比较

以拐枣果梗为原料,制备拐枣露酒与发酵酒,测定拐枣酒中营养成分含量,并采用氧自由基吸收能力（ORAC）、铁离子还原能力（FRAP）、2,2'-联氨-双（3-乙基苯并噻唑啉-6-磺酸）二铵盐（ABTS）与1,1-二苯基-2-苦肼基（DPPH）自由基清除能力4种方法对其抗氧化活性进行测定,旨在比较两种工艺拐枣酒抗氧化成分含量及抗氧化活性。结果表明,拐枣发酵酒中总多酚、总黄酮、抗坏血酸含量均高于拐枣露酒,拐枣露酒中具有较高的糖含量,发酵酒中残糖量少。两种工艺拐枣酒均具有很强的抗氧化能力,其抗氧化能力与之含有的总黄酮、总多酚及抗坏血酸含量呈显著正相关（P＜0.05）。拐枣酒的ORAC值在6.49～14.69 mmol/L之间,FRAP值在3.59～11.71 mmol/L之间,对ABTS、DPPH自由基的清除率均＞90%,半抑制浓度（IC50）值分别在7.10～20.30 μg/mL、23.40～52.30 μg/mL之间。拐枣露酒与拐枣发酵酒相比,发酵酒中营养成分含量更高,品质更佳,抗氧化能力更强。     

Effect of Ganoderma lucidum on the quality and functionality of Korean traditional rice wine, yakju

The goal of this study was to develop a high value Korean traditional rice wine possessing the pharmaceutical functionality of Ganoderma lucidum. The effects of the fruiting body of G. lucidum on the alcohol fermentation of Korean traditional rice wine, yakju, were investigated. Optimal fermentation conditions for the preparation of G. lucidum-yakju consisted of the koji added at 15% and a fermentation period of 15 d at 25 degrees C. The effects of the amount of G. lucidum added on the acceptability and functionality of G. lucidum-yakju were investigated. G. lucidum GL-1 yakju brewed by adding 0.1% G. lucidum into the mash showed the best acceptability and its angiotensin I-converting enzyme (ACE) inhibitory activity and SOD-like activity were 63% and 42%, respectively, both of which are higher than those of yakju. The high ACE inhibitory activity of G. lucidum GL-1 yakju was found to result from ganoderic acid K in G. lucidum on the basis of physical and spectral data. However, the fibrinolytic activity and antioxidant activity of G. lucidum GL-1 yakju were very low, while tyrosinase inhibitory activity was not determined. From these results, G. lucidum GL-1 yakju may become a new functional Korean traditional rice wine with antihypertensive properties.     

不同原料的米酒多酚及其抗氧化性能比较

为了更好地了解不同原料对米酒发酵过程中多酚及其抗氧化活性的影响,采用6种大米原料进行甜米酒的传统固态发酵工艺酿制.通过Folin-Ciocalteu法和高效液相色谱分别测定米酒的总多酚含量和主要酚类成分,根据ABTS自由基清除率和铁离子还原力(FRAP)检测米酒的抗氧化活性,并对米酒多酚含量与抗氧化性进行相关性分析,对...     

刺梨自然发酵制酒过程中化学成分、抗氧化活性及优势菌的变化

该研究以刺梨为原料,通过自然发酵制成刺梨果酒,对其感官、理化性质(总酸、pH、还原糖、酒精度)、抗氧化成分、体外抗氧化活性和微生物多样性进行研究。结果表明,整个发酵过程中果酒的总酸含量从9.20 g/L上升至29.69 g/L,pH值从3.26上升至3.50,还原糖含量从24.43 g/L下降至9.17 g/L,酒精度为从5.72%vol上升至9.81%vol;同时总酚含量（以没食子酸计算）为0.90~ 5.48 mg/mL,总黄酮含量（以芦丁计算）为0.46~5.43 mg/mL,抗坏血酸含量为0.89~3.37 mg/mL。发酵23 d后的刺梨果酒色泽微黄,澄清透明、香气浓郁且口感清爽。体外抗氧化活性表明刺梨发酵过程中的抗氧化能力随着发酵时间的延长先上升后降低,这一趋势与抗氧化成分变化趋势一致。抗氧化物质以及三种自由基清除率的变化表明刺梨发酵期间抗氧化活性的变化与总酚、总黄酮、抗坏血酸含量变化均显著相关。通过微生物多样性分析表明刺梨发酵中真菌主要为酿酒酵母,而细菌主要为乳酸片球菌和棘皮鞘氨醇单胞菌。     

不同处理方式的桑椹原料对其果酒品质的影响

本研究选用不同处理方式的桑椹原料酿制果酒,根据其发酵过程中酒精含量、总糖含量、色度、色调、黄酮含量、多酚含量以及花色苷含量的变化情况,选择合适的桑椹原料。结果表明,经过冷冻处理的新鲜桑椹与未经过冷冻处理的新鲜桑椹在发酵过程中各项理化指标一致,其酒精含量、总糖含量、色度、色调、黄酮含量、多酚含量、花色苷含量分别为12.9(%vol)、5.4%、2.157、0.825、11.816、178.4、11.851mg/L,冻桑椹发酵过程中的各项理化指标均可提前达到稳定状态,有利于缩短发酵周期。      

The profile in polyphenols and volatile compounds in alcoholic beverages from different cultivars of mulberry

Abstract: Mulberry fruits have different chemical compositions because of cultivar variation. In this study, polyphenol profile and volatile composition of alcoholic beverages produced from different mulberries of Da 10, Hongguo 2 hao, and Hongguo 1 hao were investigated. Statistically significant differences were detected in the chemical composition of the analyzed alcoholic beverage samples. The beverage of Da 10 possessed the highest content of total phenols, total flavonoids, and total anthocyanins, which was determined by spectrophotometry analysis, contrarily Hongguo 1 hao beverage showing the lowest. Phenolic acids and flavonols were analyzed by high performance liquid chromatography analysis. Protocatechuic acid was the main phenolic acid in all analyzed alcoholic beverage samples, and its concentration ranged from 8.20 mg L^?1 (Hongguo 1 hao beverage) to 29.98 mg L^?1 (Da 10 beverage). High level of flavonols was found in both Da 10 and Hongguo 2 hao beverage samples, whereas Hongguo 1 hao beverage sample was characterized with lower level of flavonols. Furthermore, volatile compounds were analyzed by solid phase microextraction‐gas chromatography mass spectrometry analysis. The amount of esters varied widely among the 3 alcoholic beverage samples. The concentration of aliphatic alcohols in Hongguo 2 hao and 1 hao beverage samples was higher than Da 10 sample, whereas Da 10 beverage sample contained more aromatic alcohols than the others. Hongguo 1 beverage sample showed the highest concentration of acetic acid. This study demonstrated that quantitative differences of phenolic compounds and volatile compounds among cultivars were significant, which highly affected the quality of alcoholic beverage from mulberry. Practical Application: Mulberry fruits had different chemical compositions because of cultivar variation. The analyzed Da 10 cultivar of mulberry appeared to be a good raw material for alcoholic beverage‐making because of its high level of total sugar and acidity. This study demonstrated that alcoholic beverages from mulberry contain high amounts of polyphenols. These bioactive compounds may act synergistically to promote health, and reduce risk factors of chronic diseases.     

不同品种桑椹酒抗氧化能力及其多酚含量分析

对6个不同品种的桑椹酒的总酚、总类黄酮、原花青素、总花色苷及桑椹酒中主要的两种花色苷（矢车菊-3-氧-芸香糖苷和矢车菊-3-氧-葡萄糖苷）的总抗氧化能力及其相关性进行了分析.结果表明,不同品种的总酚、总类黄酮、原花青素、总花色苷、矢车菊-3-氧-葡萄糖苷、矢车菊-3-氧-芸香糖苷和总抗氧化能力变幅和变异系数较大,存在显著差异（P＜0.05）;桑椹酒总抗氧化能力与总酚、总类黄酮、原花青素、总花色苷及矢车菊-3-氧-葡萄糖苷和矢车菊-3-氧-芸香糖苷含量之间存在正相关性,其中与总酚的相关性最强,达到0.917 2.     

The properties and stability of anthocyanins in mulberry fruits

Mulberry fruit is well known as a good source of anthocyanins with many biological activities. However, there are several colors of mulberry fruits, even from the same species, which may generate different amounts of anthocyanins. This study investigates anthocyanin content and antioxidant levels as well as tyrosinase inhibition activity in the extract from various colors of mulberry fruit, Morus alba. The effects of heat and light, which the extract may be exposed to during food processing, on anthocyanin and antioxidant activities are also evaluated. Our results show that purple-colored mulberry fruit extract contains the highest levels of anthocyanin and strongest antioxidant as well as anti-tyrosinase properties compared with other colors mulberry fruit extracts. Light or heat exposure by incubation of the mulberry fruit extract at 70 °C for 10 h significantly deteriorated total anthocyanin and ascorbic acid content and led to a corresponding increase of the IC₅₀ values.     

Evaluation of flavonoid and polyphenol constituents in mulberry leaves using HPLC fingerprint analysis

The mulberry leaf is a promising dietary source of antioxidants due to its high levels of beneficial compounds. To further examine its antioxidant properties, twelve batches of authenticated mulberry leaf, with total flavonoid contents (TFC) ranging from 24.34 mg g⁻¹ DW to 58.42 mg g⁻¹ DW and total polyphenol content (TPC) ranging from 11.49 mg g⁻¹ DW to 30.03 mg g⁻¹ DW, were investigated. According to Spearman’s coefficient, antioxidant activities, including the DPPH radical scavenging assay and the ferric reducing antioxidant power (FRAP), were positively correlated with TFC and TPC. The HPLC-DAD analysis results identified the characteristic fingerprint peaks in mulberry leaves as chlorogenic acid, rutin, quercetin 3-O-glucoside and kaempferol 3-O-glucoside, all of which directly contribute to the antioxidant capacity of mulberry leaves. Notably, young mulberry leaves showed higher antioxidant capacity than those of mature leaves. These promising results help create a compelling case for future development of mulberry leaf products.     

Physicochemical properties and antioxidant activities of commercial vinegar drinks in Korea

The purpose of this study was to evaluate the physicochemical properties of various commercially available vinegar drinks consumed in the Korean market, including their pH, acidity, sugar, total soluble sugar, total acid, total amino acid content, and antioxidant capacity. The pH values ranged from 2.81 to 3.20 and total acidity ranged from 1.95 to 2.34%. Sugar content ranged from 31.63 to 38.75°Bx. The most commonly occurring acid was acetic acid, which can serve as an indication of the taste quality of the vinegars drinks under analysis. The total amino acid content ranged from 781 to 982 mg/L. The highest total anthocyanin content was 13.21 mg% in the blackberry vinegar (BV) and the lowest was 0.06 mg% in the red ginseng vinegar (HV). The antioxidant activities of samples were also evaluated with the BV found to have the highest activity and also showed the highest total polyphenol content.     

Phenolic Profiles,Antioxidant Activities,and Neuroprotective Properties of Mulberry (Morus atropurpurea Roxb.) Fruit Extracts from Different Ripening Stages

The present work investigated the phenolic profiles (including nonanthocyanin and anthocyanin phenolics), antioxidant activities, and neuroprotective potential of mulberry fruit (MF) (Morus atropurpurea Roxb.) grown in China at different ripening stages. High‐performance liquid chromatography‐tandem mass spectrometry method (HPLC‐MS/MS) was used to identify and quantify the phenolic compounds. The antioxidant capacity, total phenolic content (TPC), total flavonoid content (TFC), and total monomeric anthocyanin content (TAC) were determined using spectrophotometric methods. The neuroprotective effects of MFs at different ripening stages were investigated using Aβ_25‐35‐treated PC12 cells as the cellular model of Alzheimer's disease. Of the 19 phenolic compounds characterized from the MF extracts, the contents of rutin and anthocyanins increased and that of chlorogenic acid decreased significantly with maturity. At the fully ripened stage, MF extracts showed the highest amounts of TPC (11.23 mg gallic acid equivalents/g fresh weight), TFC (15.1 mg rutin equivalents/g fresh weight), and TAC (1177 mg cyanidin 3‐O‐glucoside equivalents/100 g fresh weight). Meanwhile, antioxidant activity of MF extracts at this stage was highest according to ABTS (an IC50 value of 4.11 μg/mL) and DPPH (an IC50 value of 10.08 μg/mL) assays. Cellular assays revealed increased cell viability in cells treated with the ripe MF extracts; compared with the control groups, the ripening fruits also increased the antioxidant enzyme levels in PC12 cells. Together, these results suggest that the antioxidant activities and neuroprotective properties of ripening MFs are related to the contents and types of phenolic compounds that are present in the fruits.