不同水解方法对刺梨渣多酚含量及活性的影响

该研究以刺梨渣为原料,分别经酸水解、碱水解以及酶水解得到刺梨渣提取液,测定提取液中多酚含量组成及体外抗氧化能力,并比较酚类物质与抗氧化能力之间的相关性。结果表明,刺梨渣提取液中游离多酚、游离黄酮含量最高（分别为84.44 mg RE/g和136.67 mg RE/g）;碱水解得到的结合酚、结合黄酮含量最高（2.04 mg RE/g和5.89 mg RE/g）。抗氧化分析结果表明,游离酚抗氧化能力最强,对DPPH·、ABTS+·清除能力、还原铁离子和铜离子的能力分别达到854.87 μmol TE/g、995.35 μmol TE/g、336.24 μmol TE/g、1 212.08 μmol TE/g。皮尔逊相关性分析结果表明,多酚含量与抗氧化活性呈较强的正相关（P＜0.05）。综上可知,刺梨渣富含酚类物质,且碱水解处理刺梨渣能释放更多的结合酚,具有较强的抗氧化活性。     

热带水果多酚提取物的抗氧化和抗增殖活性研究

为明确12种热带水果多酚提取物的总酚含量、总抗氧化能力和抗肿瘤细胞增殖活性,分别采用Folin-Ciocalteu法确定了水果提取物的总酚含量,采用ORAC和FRAP的方法确定了其抗氧化能力,采用MTT的方法确定了其抗人肝癌细胞HepG2增殖的活性。结果显示,12种水果提取物的总酚含量为26.17-229.67 mg GAE/100g 鲜重,最高杨桃的总酚含量为最低鳄梨的8.78倍;ORAC和FRAP抗氧化值分别为607.05-2631.17 μmol TE/100g 鲜重和462.12-1067.92 μmol TE/100 g鲜重,杨桃具有最高的ORAC和FRAP抗氧化值,分别是最低木瓜的4.33倍和鳄梨的2.31倍;11种水果提取物抑制肿瘤细胞HepG2增殖的IC50值为31.79-66.93 mg/mL,抑制活性最弱木瓜的IC50值为最强杨桃的2.11倍。水果提取物的总酚含量与其ORAC抗氧化值（R2＝0.7839）、FRAP抗氧化值（R2＝0.7636）和抑制HepG2细胞增殖的IC50值（R2＝0.8847）之间具有显著的相关性。     

基于HepG2细胞模型的香菇柄粉多酚抗氧化及抗增殖活性

以人肝癌细胞HepG2为细胞模型,经过不同粉碎条件处理香菇柄粉后,研究香菇柄粉游离酚的细胞抗氧化及多酚抗增殖活性。结果表明：香菇柄粉游离酚的细胞抗氧化活性（cellular antioxidant activity,CAA）值为9.90～24.22 μmol QE/100 g,普通粉碎组最高,纳米超微粉碎组最低,CAA值随粉体粒径减小而降低（不经磷酸盐缓冲液（phosphate buffer saline,PBS）清洗）;气流超微粉碎组CAA值为0.65 μmol QE/100 g,普通粉碎组和纳米超微粉碎组未表现出细胞抗氧化活性（PBS清洗）。香菇柄粉游离酚的抗增殖活性（半数有效浓度（medianeffective concentration,EC50）值）为1.888～5.213 mg/mL,结合酚的抗增殖活性（EC50值）为2.225～4.751 mg/mL,气流超微粉碎处理对香菇柄粉结合酚的抗增殖活性有增强作用。     

不同发酵工艺对刺梨果酒抗氧化活性的影响

为更好利用刺梨果酒抗氧化活性物质,本研究通过检测6种发酵工艺加工的刺梨果酒的各项指标和体外抗氧化活性,以及利用主成分分析构建的综合评价体系考察刺梨果酒的品质。结果表明,6种发酵工艺中刺梨果酒可溶性固形物无显著性差异;三种自然发酵工艺中酒精度、还原糖、甲醇、Vc无显著性差异;三种灭菌发酵工艺中pH、总酸、酒精度、总糖、Vc和总酚无显著性差异;自然原汁发酵的pH值（3.47）、SOD(66.12 U/mL)、总糖（241.75 mg/mL）、总酚（98.03 g/L）和总抗氧化能力（2.569 mg/mL）与其他发酵工艺存在显著性差异;灭菌冷浸渍发酵的还原糖（5.55 mg/mL）显著低于其他发酵工艺。主成分分析表明,自然带渣发酵工艺发酵刺梨果酒综合分数最高（1.050）,是适合刺梨果酒酿造的发酵工艺。     

模糊综合评判结合响应面法优化发酵刺梨-火棘果风味果冻配方

该研究以发酵刺梨汁、发酵火棘果汁和银耳为主要原料制作发酵刺梨-火棘果风味果冻。以感官评分和持水力的模糊综合评判值为评价指标,在单因素试验的基础上,采用模糊综合评判结合响应面法对其配方进行优化,并对其营养成分进行检测。结果表明,发酵刺梨-火棘果风味果冻的最佳配方为发酵刺梨汁添加量9%,发酵火棘果汁添加量15%,银耳添加量14%,甜菊苷添加量0.02%,氯化钾添加量0.4%,复合胶（魔芋胶∶卡拉胶=6∶4）添加量1.0%。在此配方下,发酵刺梨-火棘果风味果冻软硬适中,质地均匀有弹性,酸甜可口,具有独特发酵果香风味,感官评分为94.04分,持水力为95.04%,模糊综合评判值为0.95,维生素C、总糖、总酸、总黄酮、总酚含量分别为22.93 μg/mL、10.55 mg/mL、3.23 g/L、15.20 mg 芦丁当量（RE）/mL、38.24 μg 没食子酸当量（GAE）/mL。     

超高压与热杀菌对刺梨汁贮藏期品质影响的比较

本实验对比了超高压（500 MPa、10 min）和传统热杀菌（90 ℃、15 min）对刺梨汁处理前后及4 ℃、30 d贮藏期内微生物、理化指标、色泽、活性成分等的影响。结果表明,两种处理使刺梨汁菌落总数均小于1.0（lg（CFU/mL））,贮藏结束时,超高压与热处理组菌落总数分别为1.83（lg（CFU/mL））和2.60（lg（CFU/mL））;两种处理均使刺梨汁L*值显著上升（P＜0.05）,热处理刺梨汁褐变度显著高于超高压处理（P＜0.05）,表明超高压能更好地保持刺梨汁原有的色度;贮藏期间b*值呈现下降趋势;与热处理相比,超高压处理能更好地保持刺梨汁中的总酚、VC水平及超氧化物歧化酶（superoxide dismutase,SOD）活力。贮藏结束时,超高压组总酚、VC质量浓度、SOD活力及抗氧化活性的保留率分别为93.32%、52.80%、64.49%、93.96%,热处理组总酚、VC、SOD活力与抗氧化活性的保留率分别为81.68%、28.35%、41.65%、93.30%。综上,超高压处理相较于传统热处理在保持刺梨汁品质特性与抗氧化物质方面有显著优势,可作为一种新型刺梨汁饮料加工技术。     

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。     

超高压和高温短时杀菌对沙棘汁品质的影响

为了筛选出适合制汁的沙棘品种,对‘中国沙棘’‘圣果一号’‘深秋红’3 种沙棘的理化品质进行比较。结果表明,‘中国沙棘’具有最高的超氧化物歧化酶（superoxidative dismutase,SOD）活力（（1 029.14±77.72）U/g）、总酚含量（（8.37±0.20）mg GAE/g）及抗氧化能力（1,1-二苯基-2-三硝基苯肼自由基清除能力（11.04±0.27）mmol TE/100 g、铁离子还原抗氧化能力（6.06±0.32）mmol TE/100 g）。沙棘汁（经‘中国沙棘’制得,下同）经浓缩后SOD活力提高2.5 倍以上,可作为功能性产品。对超高压（high pressure processing,HPP）（500 MPa/6 min）或高温短时（high-temperature short-time,HTST）（100 ℃/15 s）处理后的沙棘汁品质进行了比较。两种处理都可以使沙棘汁中的菌落总数下降超过3（lg（CFU/mL））,且使霉菌和酵母无法检出。此外,两种处理均提高了沙棘汁中SOD的活性,其中HPP处理组的SOD活性在贮藏期间更高。两种处理均很好地保留了总酚、抗坏血酸含量及抗氧化能力,且这些品质指标在4 ℃冷藏期间同样得到很好的保留。综上,HPP和HTST处理的沙棘汁都是具有高SOD活性和抗氧化能力的产品。     

梨中不同形态酚类化合物的抗氧化活性对比分析

本文采用溶剂提取法对梨皮和梨肉中的自由酚和结合酚进行提取,并采用DPPH法测量梨皮及梨肉的抗氧化活性。研究结果表明,梨皮中总酚含量为(201.26±6.90)×10-2mg/g鲜梨(以没食子酸计),其中自由酚为135.36±1.57 mg;结合酚为42.46±3.05 mg;梨肉中总酚含量为(23.73±2.28)×10-2mg/g鲜梨肉(以没食子酸计),其中自由多酚含量为12.54±0.98 mg,结合酚11.19±1.30 mg。黄酮含量与多酚含量呈良好正相关。通过比较梨皮梨肉中两种自由酚抗氧化活性,得出梨肉自由酚的抗氧化活性最高,DPPH清除率的EC50为248.59μg/mL,AE值为0.0040;梨肉结合酚的抗氧化活性较低低,DPPH清除率的EC50为1043.24μg/mL,AE值为0.0010。     

全缘马尾藻褐藻多酚的抗氧化和抗肿瘤细胞增殖作用研究

检测全缘马尾藻褐藻多酚提取物(IPTs)的抗氧化和抗肿瘤细胞增殖作用。通过萃取和超滤获得4种IPTs提取物-IPTa1、IPTa2、IPTe1和IPTe2,总酚含量分别为1.16、0.6、0.25和0.34 mg没食子酸（GA）/g海藻干基,1.5 mg/L时的总抗氧化能力（TCA）分别相当于1.724、1.379、1.833、0.695 mg/L的Fe2+还原能力;MTT结果显示,4.4 μg/mL时,4种IPTs提取物作用sw579细胞24 h、48 h、72 h后,除了IPTa2外,IPTa1、IPTe1和IPTe2均以时间依赖方式显著抑制肿瘤细胞的生长;0.3125~5 μg/mL浓度范围内,IPTa1和IPTe1的抑制率与作用时间和浓度呈正相关,最高抑制率达90%以上。     

Sensory and physicochemical characterization of juices made with pomegranate and blueberries, blackberries, or raspberries

The quality parameters of 1 commercial pomegranate juice mixed with 5 different concentrations of blueberry, blackberry, or raspberry juices were studied. The pH, total soluble solids content, titratable acidity, and total phenolic content were determined. To understand the aroma differences of the juices, solid phase microextraction-gas chromatography-mass spectrometry was used to determine the volatile compounds present in the mixtures. A consumer study also was carried out to relate consumer ratings to the instrumental data and to determine acceptance and possible modifications of the designed juices. Four juices received the highest scores in overall consumer liking: pomegranate/blueberry juice with 20% and 50% of blueberry, pomegranate/blackberry with 10% of blackberry, and pomegranate/raspberry with 10% of raspberry. The main characteristics in these juices were: a high maturity index (from 13.9 to 16.5), low acidity (0.79 to 1.09 g citric acid 100 per milliliter juice), and the presence of aromatic compounds typical in blueberries such as 6-methyl-5-hepten-2-one, α-terpineol, and E-nerol. The total phenolic content was significantly higher in the pomegranate/blackberry 90%/10% sample, raising around 3500 mg gallic acid equivalents per liter, and could be a positive determinant for consumers interested in purchasing healthful products. PRACTICAL APPLICATION: The data presented in this article will help the juice industry, in the United States and elsewhere, to understand the consumer's preferences for pomegranate blended juices. Pomegranate juices have high antioxidant content, which makes these juices more desirable for the health-conscious consumer of today.     

Biological activity and chemical composition of different berry juices

Total phenolics, total anthocyanins, mineral content, radical scavenging activity and antiproliferative activity against human cancer cell lines were evaluated in fresh pressed juices of five different berries. Total phenolic content ranged from 133.0 to 260.3 mg of gallic acid equivalents/100 g of fresh weight, for red currant and black currant, respectively. Bilberry juice contained the highest amount of total anthocyanins (0.18%). Significant correlation between total phenolics content and radical scavenging activity was observed (r = −0.980; p < 0.01). All examined juices showed antiproliferative activity in dose-dependent manner with IC₅₀ ranging from 10.2 to 70.5 μl/ml. Black currant juice was the most effective inhibitor of proliferation in all cell lines tested (HeLa, Fem X, LS 174, MCF-7 and PC-3). Significant correlations of acidity and total anthocyanin content with antiproliferative activity of berry juices on HeLa cells, Fem X cells and MCF-7 cells were noticed. Berry juices are good sources of some minerals and contribute significantly to daily intake of these micronutrients.     

草莓、黑莓、蓝莓中多酚类物质及其抗氧化活性研究

研究草莓、黑莓、蓝莓3种小浆果的总酚、总黄酮、原花青素含量及其总抗氧化能力。结果表明:蓝莓全果的总酚、总黄酮、原花青素含量在所测3种浆果全果中最高,分别为9.44mg没食子酸/g干质量、36.08mg芦丁/g干质量、24.38mg儿茶素/g干质量;其总抗氧化能力也最强,达14.98mmol Trolox/100g干质量。草莓的总酚、总黄酮、原花青素含量则最低,抗氧化能力也最弱。此外,3种浆果果渣中的总酚、总黄酮、原花青素含量以及总抗氧化能力均高于全果和果汁,即果渣>全果>果汁。总酚含量、总黄酮含量以及原花青素含量与总抗氧化能力之间的相关性分析表明,总酚含量与总抗氧化能力之间存在显著线性相关,相关系数r达到0.9704,表明酚类物质是其抗氧化作用的主要物质基础。     

Phenolic Profile and Antioxidant Activity of Polish Meads

The purpose of this study was to evaluate phenolic profile and antioxidant activity of ten different meads of 1:1 and 1:2 types, produced with addition of fruit juices, root spices, and herbs. The total phenolic content in meads varied from 15.27 to 70.80 mg/dm³. The meads originated from dark honeys exhibited the highest antioxidant activity. The predominant phenolic compounds in meads were hydroxybenzoic acids, especially gallic and protocatechuic acid, originated mainly from honeys. Whereas, among the hydroxycinnamic acids, the major phenolic was chlorogenic acid, derived mainly from plant additives used in meads production. A principal component analysis was applied in order to differentiate the investigated meads. The 1:2 meads type could be best described by chlorogenic acid. Among the 1:1 meads type, those made from the dark honeys could be best described by gallic, p-coumaric, and protocatechuic acid while those made with addition of blackcurrant and raspberry juice could be described by caffeic and ferulic acid.     

Pectinesterase Activity and Proximate Analyses of Sea Buckthorn Juices

Three varieties of sea buckthorn fruit were harvested and pressed to obtain juices. These were analyzed for pectin methylesterase activity, moisture, nitrogen, oil, pH, total acid, and °Brix. Yields of press juice for Hippophae rhamnoides ssp. rhamnoides L. varieties Luchistaya, Prozrachnaya, and ssp. mongolica Rousi cv. Indian Summer were 68%, 69%, and 66% w/w, respectively. Differences in juice composition were found to be in moisture content, °Brix, pH, and in total acid with the Luchistaya variety having the highest acid levels and lowest pH. Pectin methylesterase (PME) was present in all sea buckthorn juices with initial activity levels of 6.8 to 14.0 μ equivalents per min per 100 g of juice at pH 8 and 23 °C. Activity was pH‐dependent with little PME activity at pH 3 to 5 and the highest activity at pH 8. The cream, pellet, and serum layers of centrifuged juices all contained PME. Heat treatment reduced PME activity in the juices by 1 decimal reduction or less.     

壳聚糖澄清对沙棘果汁酚类成分的影响

通过Folin—ciocalteu比色法测定和HPLC检测分析，对壳聚糖澄清过程中沙棘果汁总酚含量以及一些酚类成分的变化进行了研究，结果显示：壳聚糖澄清对沙棘果汁中的酚类物质有所影响，总酚含量降低了17．2％，澄清后果汁中的儿茶酸、阿魏酸和香豆酸组分损失，没食子酸降低87％，槲皮素减少了62．5％，绿原酸含量变化不大。