Identification of Polyphenols from Unripe Apple with Viscozyme L Extraction

As a potential source of fine chemicals, unripe apple polyphenols were extracted with Viscozyme L treatment. And then, a preparative moderate pressure liquid chromatography(MPLC) method for separation and purification of polyphenols were successfully established by using silica gel column and octadesyl silane column. The structures of these compounds were identified by ~1H and ^(13)C NMR spectroscopy. The results indicated that Viscozyme L had the strongest effect on polyphenols extraction, the yield of apple crude polyphenols(ACP) was 7.08%, and the total phenolic content(TPC) of ACP was 0.95 g GAE/100 g, which were 2 times of that of control; 5 sub-fractions were obtained from ACP, which were A-1, A-2, and B-1, B-2, B-3; fractions A-2 and B-2 were identified as p-coumaric acid and caffeic acid and the yields were 111.54 and 161.70 mg/100 g ACP, respectively. In addition, p-coumaric acid and caffeic acid were the major components in Viscozyme L-aided polyphenols extraction, which could be explained by the result of degradation of lignin and chlorogenic acid by carbohydrate-hydrolyzing enzyme, Viscozyme L.

Polyphenolic Compound and the Degree of Browning in Processing Apple Varieties

Polyphenolic compound in processing apple （Malus domestica Borkh.） varieties and the relationship between polyphenol content and enzymatic browning were studied to provide reference for raw material selection and processing method optimization. The content of polyphenol compound in 10 processing apple varieties （4 cider and 6 juice varieties） were analyzed using the Folin-Ciocalteu method and HPLC. The degree of browning and the activities of polyphenol oxidase were also studied. The content and proportion of the polyphenol varied depending on the variety. Bitter varieties globally showed a higher polyphenol concentration than sweet or acid varieties. Proanthocyanidins, chlorogenic acid, （＋）-catechin, （-）-epicatechin were high-concentrated polyphenols in apple fruits. Phloridzin, the unique polyphenol of apple, was abundant in the bitter variety Frequin rouge fruit. Total polyphenols, proanthocyanidins, （＋）-catechin, and phloridzin had higher correlations with browning. The correlation was low between chlorogenic acid and browning. The polyphenolic profiles were correlated with the apple types. Cider apples contained more polyphenol than juice apple varieties. The content of flavan-3-ol has a close relationship with fruit browning.

Comparative study on the weight loss and lipid metabolism by tea polyphenols in diet induced obese C57BL/6J pseudo germ free and conventionalized mice

The role of gut microbiota in terms of host health is becoming increasingly important.In this study,the comparative effects of tea polyphenols(TPs)on weight loss and lipid metabolism on conventionalized mice(CVZ)and pseudo germ-free(PGF)mice(treated with antibiotics)were investigated.Our findings revealed that high fat(HF)diet considerably increased the body weight,total fat and upsurge lipid indices in CVZ mice but PGF mice were not sensitive to the effect of HF diet as CVZ mice.After the dietary administration of TP,body weight,perirenal fat and epididymal fat,liver weight,glucose(GLU)level,total chloestrol(TC level),high density lipoprotein-cholesterol(HDL-C)level significantly lowered in PGF mice as compared to CVZ mice group.However,the area of fat cells and triglyceride(TG)level were significantly increased in PGF mice.In CVZ mice,TP intervention resulted in a considerable drop in the Firmicutes/Bacteroides ratio as compared to PGF mice.The intestinal flora of PGF mice was severely reduced after antibiotic treatment,while TP administration restored intestinal diversity;the abundance of Akkermansia and Lactobacillus increased,whereas the abundance of Enterobacteriaceae and Prevotella reduced.Overall,we can assume that PGF obese mice administered with TP have less anti-obesity effects compared to obese CVZ mice.

Polyphenol Oxidase Activity and Colour Changes of ‘Starking’ Apple Cubes Coated with Alginate and Dehydrated with Air

The objective was to study the effect of alginate coating on polyphenol oxidase (PPO) activity and colour of ‘Starking’ apple cubes during dehydration with hot air. Apple cubes were dehydrated at 20oC, 35oC, or 40oC, with a parallel airflow. Analysis of PPO activity, colour (L*, a*, b*) and dry matter were performed along the dehydration process at each temperature. All samples presented a peak in relative PPO activity in the beginning of the drying. Exponential models fitted well the experimental data after the peak. Cubes without coating presented lower PPO activity, suggesting lower browning, than coated samples throughout the dehydration process, for all temperatures. Better results for coated samples were obtained with a perpendicular airflow drying at 40oC, after dipping the whole apple in water at 60oC for 10 min. In order to prevent coated samples from browning, drying by perpendicular airflow preceded by a thermal treatment of the whole apple is required.

Improving Oxidative Stability of Polyphenolic Fraction of Apple Pomace by Encapsulation Using Naturally Occurring Polymers

Polyphenolic compounds with relatively high antioxidant activity obtained from subcritical water extraction of apple pomace were assessed for encapsulation by spray drying technique, making use of polymeric substances co-extracted with the polyphenolic compounds. Comparative assessments were carried out of the directly encapsulated subcritical water extract (SWE) products with particles formed when encapsulated with the addition of hydroxyl propyl-β-Cyclodextrin (SWE + HPβ-CD). The powders were characterized for their physico-chemical properties such as, moisture content, density, particle size, hygroscopicity to assess their suitability within cosmetic formulations. The SWE and SWE + HPβ-CD encapsulated products resulted in different physical properties. Although the particle size was less than 4 μm for both products, the direct encapsulation (SWE) was highly hygroscopic and this property was significantly reduced with addition of HPβ-Cyclodextrin (SWE + HPβ-CD). Scanning electron microscopy (SEM) and Fourier Transform Infrared (FT-IR) spectroscopic were em-ployed to analyse the micronised powders to support evidence of encapsulation. Both techniques revealed the interaction between compounds in extract and the carrier HPβ-Cyclodextrin suggesting successful encapsulation. The effect of storage conditions on retention of antioxidant activity of the subcritical water extract was evaluated within 35 days for extracts with and without the carrier HPβ-Cyclodextrin. Hydroxyl propyl-β-Cyclodextrin offered protection against degradation of antioxidant compounds thereby potentially extending the shelf-life and making the encapsulated powder suitable for incorporation in cosmetic and pharmaceutical applications.

Apple polyphenols attenuate the binding ability of angiotensin converting enzyme 2 to viral proteins: Computer simulation and in vitro experiments

To investigate the effects of apple polyphenols on ACE2 and its antibody binding, computer simulation and experiments in vitro were conducted. The results of molecular docking and molecular dynamics showed that apple polyphenols had a good binding effect on RBD and RBD-ACE2 complex. Fluorescence analysis exhibited that the three main apple polyphenols had a fluorescence quenching effect on the ACE2 antibodies, and the quenching mechanism was static. The results of the circular dichroism experiment suggested that apple polyphenols could change the secondary structure of the ACE2 antibodies. Western blot results displayed that apple polyphenols inhibited the binding of ACE2 and its antibodies. This study confirmed that apple polyphenols could bind ACE2 antibodies in vitro. Therefore, it is speculated that apple polyphenols have similar effects on a class of proteins with similar ACE2 recognition sites, which may potentially inhibit viral protein and ACE2 recognition, thus preventing viruses from entering host cells.

Functional properties, phenolic constituents and antioxidant potential of industrial apple pomace for utilization as active food ingredient

Apple pomace is a waste biomass generated after apple fruit processing.In present investigation,efforts were made to comprehend influence of differently dried pomace on cell wall properties and phenolic profile.Different drying techniques were employed to remove moisture content from fresh apple pomace.Total dietary fiber yield(74%)and array of functional properties such as density,water and oil holding capacity,swelling capacity and glucose dialysis retardation index(36.91%)was found better in freeze dried fraction.The higher total phenolics(5.78±0.08 mg GAE/g dry weight)content was also recorded in freeze dried fraction followed by oven and sun drying.The 50%aqueous acetone was found as more efficient solvent for extraction of phenolic constituents.RP-HPLC analysis has revealed presence of quercetin,phloridzin and phloretin as major phenolics.Thus,it is evident from the results that pomace generated at industrial scale can be utilized as a source of dietary food ingredient.

Apple as a Source of Dietary Phytonutrients: Bioavailability and Evidence of Protective Effects against Human Cardiovascular Disease

The dietary consumption of fruit and vegetable is associated with a lower incidence of degenerative diseases such as cardiovascular disease. Most recent interest has focused on the bioactive phenolic compounds in vegetable products. All varieties of apple contain several antioxidants and polyphenols that possess many biological activities, such as antioxidant and anti-inflammation properties. The review describes the nutritional properties of apples and their derivatives, with a particular attention to polyphenol compounds. Moreover, the health benefits of apples and the potential molecular mechanisms against cardiovascular disease are reviewed.

Hypotriglyceridemic Effects of Apple Polyphenols Extract via Up-Regulation of Lipoprotein Lipase in Triton WR-1339-Induced Mice

Objective：To investigate the anti-hyperlipidemic effects of apple polyphenols extract（APE）in Triton WR-1339-induced endogenous hyperlipidemic model.Methods：Firstly,APE was isolated and purified from the pomace of Red Fuji Apple and contents of individual polyphenols in APE were determined using highperformance liquid chromatography-mass spectrometry（HPLC-MS）.Secondly,forty male National Institude of Health（NIH）mice were randomly divided into 5 groups with 8 animals in each group.The Fenofibrate Capsules（FC）group and APE groups received oral administration of respective drugs for 7 consecutive days.All mice except those in the normal group were intravenously injected through tail vein with Triton WR-1339 on the6th day.Serum and livers from all the mice were obtained 18 h after the injection.The changes in serum total cholesterol（TC）,triglyceride（TG）,lipoprotein lipase（LPL）and hepatic triglyceride lipase（HTGL）were measured by respective kits.Finally,expression of hepatic peroxisome proliferator-activated receptor alpha（PPARα）mRNA was measured by real-time reverse transcription-polymerase chain reaction（RT-PCR）method.Results：Serum TC and TG levels significantly increased in Triton WR-1339-induced model group compared with the normal group（P〈0.01）.Oral administration of APE[200 and 400 mg/（kg·day）]dose-dependently reduced the serum level of TG in hyperlipidemic mice（P〈0.01）.Serum LPL and HTGL activities significantly decreased in Triton WR-1339-induced model group compared with the normal group（P〈0.05）.Oral administration of APE[200 and 400 mg/（kg·day）]dose-dependently elevated the serum activity of LPL in hyperlipidemic mice（P〈0.05or P〈0.01）.Furthermore,compared with the normal group,hepatic mRNA level of PPARαin the model group significantly decreased（P〈0.01）.Oral administration of APE[200 and 400 mg/（kg·day）]dose-dependently elevated the expression of PPARαin hyperlipidemic mice（P〈0.05 or P〈0.01）.Conclusion：APE could reduce TG level via up-regulation of LPL activity,which provides new evidence to elucidate the anti-hyperlipidemic effects of APE.

S1B-3 Baicalin Modulates APPL2/Glucocorticoid Receptor Signaling Cascades,Promotes Neurogenesis,and Attenuates Emotional and Olfactory Dysfunctions in Chronic Corticosterone-Induced Depression

Olfactory dysfunction is accompanied with anxiety-and depressive-like behaviors.Impaired neurogenesis in hippocampus and subventricular zone(SVZ)-olfactory bulb(OB)contribute to anxiety-and depressive behaviors and olfactory dysfunctions.However,the underlying mechanisms remain unclear.Adaptor proteins containing the pleckstrin homology domain,phosphotyrosine binding domain,and leucine zipper motif(APPLs)are involved in regulating many biological activities.APPL2 showed the potentials to modulate cell growth,but whether APPL2 could affect adult neurogenesis and animal mood behaviors remains unknown.Herein,we tested the hypothesis that APPL2 could affect glucocorticoid receptor(GR)signaling and modulate hippocampal neurogenesis,contributing to depressive and anxiety behaviors.APPL2 Tg mice had enhanced GR phosphorylation under basic condition but had no different plasma corticosterone(CORT)level and GR phosphorylation under stress stimulation.APPL2 Tg mice had decreased hippocampal neurogenesis that was reversed by GR antagonist RU486.APPL2 Tg mice had impaired hippocampal neurogenesis and depressive and anxiety behaviors.We further identified the roles of APPL2 in olfactory functions.APPL2 Tg mice displayed higher GR activity and less neurogenesis at olfactory system with less olfactory sensitivity than WT mice,indicating that APPL2 could be a potential therapeutic target for depression and olfactory deficits.We then studied the effects of baicalin,a natural antioxidant,on modulating APPL2/GR signaling pathway and promoting neurogenesis for antidepressant and improving olfactory functions.Baicalin inhibited APPL2/GR signaling pathway and improved neurogenesis at SVZ,OB,and hippocampus in APPL2 Tg mice and chronic corticosterone-induced depression mouse model.Baicalin attenuated depressive-and anxietylike behaviors and improved olfactory functions in chronic depression mouse model and APPL2 Tg mice.In conclusion,APPL2 could be a novel therapeutic target for improving depressant related olfactory dysfunctions.Antioxidant therapy with baicalin could inhibit APPL2-mediated GR hyperactivity and promote neurogenesis,releasing depressive and anxiety symptoms and improving olfactory functions.

Predictive Models for Optimisation of Acetone Mediated Extraction of Polyphenolic Compounds from By-Product of Cider Production

Response surface methodology (RSM) was applied to provide predictive models for optimisation of extraction of selected polyphenolic compounds from cider apple pomace under aqueous acetone. The design of experiment (DoE) was conducted to evaluate the influence of acetone concentration % (v/v), solid-to solvent ratio % (w/v), temperature (&#730C) and extraction time (min) and their interaction on phenolic contents, using the Central Composite Rotatable Design (CCRD). The experimental data were analysed to fit statistical models for recovery of phenolic compounds. The selected models were significant (P 0.05), except for Chlorogenic acid and Quercetin 3-glucoside which had significant lack of fits (P R2 > 0.9000 and adjusted? ?reasonable agrees with predicted . Coefficient of variation < 5% for each determination at the 95% confidence interval. These models could be relied upon to achieve optimal concentrations of polyphenolic compounds for applications in nutraceutical, pharmaceutical and cosmetic industries.

蜂蜜对苹果酶促褐变的抑制及有效成分分析

作者以防止新鲜苹果切口的褐变为目标,比对不同食品配料组成的复配成分,发现蜂蜜作为涂膜材料可以有效延缓鲜切苹果片的褐变。将鲜切苹果片浸泡在质量分数0.1 g/g的椴树蜂蜜水溶液中,8 d后其仍能维持新鲜的色泽;探究了蜂蜜对苹果多酚氧化酶(polyphenol oxidase,PPO)抑制的动力学,发现蜂蜜对苹果PPO起非竞争性抑制作用,酶活抑制能力来自蜂蜜的抗氧化、清除自由基(相关系数r>0.6)能力;进一步分析蜂蜜成分与酶活抑制率的关系,发现蜂蜜中蛋白质与多酚(r值分别为0.79、0.63)是蜂蜜发挥抗褐变作用的重要成分。

苹果幼果果粉对体外模拟人体结肠微生物群的影响

以苹果幼果为原料,采用真空冷冻干燥技术制备苹果幼果果粉(YAP),测定多酚和膳食纤维等主要成分含量,通过三阶段连续发酵系统模拟结肠发酵,并结合16S rRNA高通量测序和G C-MS分析,探究苹果幼果果粉对健康和肥胖志愿者结肠微生物群组成及短链脂肪酸的影响。结果表明,YAP中含有丰富的膳食纤维[(417.50±0.40)mg/g]和多酚类物质[(57.10±0.03)mg/g]。YAP使健康和肥胖志愿者的结肠反应器中菌群组成发生变化,其中Alpha多样性没有显著变化,而Beta多样性存在显著变化。低剂量YAP对结肠中不同细菌群的相对丰度有显著影响。在健康组中,YAP显著增加了拟杆菌门(Bacteroidota)的相对丰度,降低了变形菌门(Proteobacteria)的相对丰度;在肥胖组中,YAP显著增加了放线菌门(Actinobacteriota)的相对丰度。YAP对2个实验组属水平结肠微生物均有调节作用,使其相对丰度在7 d发酵周期内达到稳定值。此外,YAP促进了产短链脂肪酸菌的生成,增加了健康和肥胖志愿者结肠中的总短链脂肪酸浓度,短链脂肪酸中乙酸浓度最高。低剂量YAP显著增加了结肠样本中戊酸、丁酸和己酸的浓度(P<0.05)。体外模拟结肠发酵的结果表明,富含多酚和膳食纤维的YAP可显著调节健康和肥胖志愿者的结肠微生物群组成和短链脂肪酸含量,研究旨在为肠道菌群饮食调控提供新的思路和理论依据。

三种多酚类物质协同L-精氨酸对冷藏鸡肉糜氧化稳定性和品质的影响

为探讨苹果多酚(Apple polyphenols,Ap)、葡萄籽提取物(Grape seed extraction,GSE)和茶多酚(Tea polyphenols,Tp)分别协同L-精氨酸(L-arginine,L-Arg)对冷藏鸡肉糜氧化稳定性和品质特性的影响,在肉糜中添加5 g/kg L-Arg,再分别加入0.2 g/kg的Ap、GSE、Tp,以添加0.2 g/kg丁基羟基茴香醚(Butylated hydroxy anisole,BHA)作为阳性对照,分别在冷藏1、3、5、7 d时测定各组鸡肉糜硫代巴比妥酸(Thiobarbituric acid reactive substances,TBARS)值、总巯基含量、羰基含量、表面疏水性、pH、蒸煮损失率和色度值。结果表明,与空白(不添加多酚类物质、L-精氨酸及BHA)和BHA相比,L-Arg+Tp可以更好地抑制鸡肉糜的TBARS、羰基含量、pH和表面疏水性的升高,减缓总巯基含量和红度值的降低。L-Arg+Ap和L-Arg+GSE与BHA的抗氧化作用相近。综上所述,在冷藏过程中L-Arg协同3种多酚类物质均可以抑制鸡肉糜的脂肪和蛋白质氧化,改善其品质特性,其中L-Arg+Tp的效果最好。

Variation in Polyphenolics and Antioxidant Activity of Traditional Apple Cultivars from West Himalaya,Uttarakhand

Apple(Malus × domestica) is largely known for polyphenolic and antioxidant properties; however, systematic investigation in the apple growing in the Indian Himalayan region is not carried out. The present study therefore, attempts to quantify polyphenolics and antioxidant activities in three traditional apple cultivars namely 'Benoni', 'Fanny' and 'Rymer' growing at different locations of Uttarakhand(west Himalaya), India.Results revealed that phenolic(0.94–7.00 mg GAE·g^(-1)FW), flavonoid(1.02–9.86 mg QE·g^(-1)FW), flavonol(0.77–6.92 mg CE·g^(-1) FW), tannin(15.49–37.99 mg TAE·g^(-1) FW) and antioxidant activity(ABTS, 3.10–67.36; DPPH, 4.99–14.06; FRAP, 4.70–39.21 mmol AAE·kg^(-1)FW) varied significantly among the cultivars and maximum content was recorded in Rymer fruits of Mukhwa location. Altitude showed significant(P < 0.05) positive relationship with total phenolic(r = 0.895), flavonoid(r = 0.843), flavonol(r = 0.812), ABTS(r = 0.856) and FRAP activity(r = 0.830). Based on the results, it is concluded that among three cultivars, Rymer is one of the most promising sources of polyphenolic content and antioxidant activity and therefore, recommended for mass plantation at suitable locations in Uttarakhand for harnessing maximum potential.

冰片茶多酚纳米乳对AD模型小鼠Aβ、BACE-1表达和认知功能的影响

目的探讨冰片茶多酚纳米乳对阿尔茨海默病(AD)模型小鼠脑和视网膜内β-淀粉样蛋白(Aβ)、β-分泌酶-1(BACE-1)表达及学习认知功能的影响。方法取昆明小鼠36只,随机分为空白对照组、AD对照组、茶多酚干预组、高/中/低(H/M/L组)浓度冰片茶多酚纳米乳干预组。经三氯化铝(AlCl3)联合D-半乳糖构建AD模型,不同浓度(H/M/L组)冰片茶多酚灌胃干预后,Morris水迷宫检测小鼠认知功能,取脑和视网膜组织石蜡包埋后,进行免疫组化检测Aβ、BACE-1表达。结果水迷宫检测后,与空白对照组相比,AD对照组、茶多酚干预组、各浓度冰片茶多酚纳米乳干预组小鼠逃避潜伏期长,跨越平台次数短,除冰片茶多酚纳米乳中剂量组外,均P<0.05。与空白对照组相比,AD对照组小鼠脑和视网膜内Aβ、BACE-1阳性产物表达增多,均P<0.05。与AD对照组相比,茶多酚和不同浓度冰片茶多酚纳米乳组小鼠脑和视网膜内Aβ、BACE-1阳性产物表达均减少,其中中剂量冰片茶多酚干预组与AD对照组比较P<0.05。结论冰片茶多酚纳米乳能有效改善AD模型小鼠认知功能障碍,抑制脑和视网膜内Aβ、BACE-1表达,为茶多酚用于AD治疗研究提供实验依据。

基于海藻酸钠复合苹果多酚的化学光热抗菌敷料的制备及抗菌效果观察

目的制备一种新型的化学/光热联合治疗细菌感染的非抗生素伤口抗菌敷料。方法以Fe^(3+)、海藻酸钠(SA)和苹果多酚(APP)3种天然物质为原料,通过冷冻干燥原位非共价交联构建海绵状骨架制备一种海藻酸钠复合苹果多酚的光热抗菌敷料SA/APP/Fe^(3+)(SAF)。以体内外试验验证其生物安全性、止血能力及杀菌能力。结果在近红外辐射下,SAF抗菌敷料能杀死近80%金黄色葡萄球菌和85%大肠杆菌。SAF抗菌敷料的细胞存活率高于95%,溶血率为6.75%;与纱布相比,SAF抗菌敷料的失血量减少了26%,止血时间减少了76%。结论制备的抗菌敷料具有较强的抗菌效果,且生物安全性高、止血能力强。

苹果多酚延长胡麻油贮藏期和维持较好品质的研究

对苹果多酚对胡麻油贮藏效果及胡麻油的体外抗菌活性进行研究。将胡麻油分别贮藏在10,4,0℃下,同时,各温度另设一多酚处理组,每组7瓶,油样品均贮藏于冷库,每隔3个月随机取出3份样品,测其酸值、过氧化值,并分析胡麻油的抗菌性。结果表明,在贮藏期间(10,4,0℃),各组胡麻油的酸值和过氧化值均随时间延长而增加,相比各对照组,各多酚处理组胡麻油的酸值和过氧化值在各测试时间点均较低;体外抗菌试验中,各组胡麻油均显示了一定的抗菌活性,贮温越低,胡麻油的抗菌活性越强,且多酚处理各组胡麻油的抗菌活性均较各自对照组强。研究表明,苹果多酚能够有效延长胡麻油的贮藏期,维持胡麻油的品质。

苹果山楂番石榴提取物体外协同降糖降脂作用研究

以苹果、山楂、番石榴为原料,利用超声辅助法提取苹果中的多酚、山楂中的黄酮、番石榴中的多糖作为α-淀粉酶、α-葡萄糖苷酶和胰脂肪酶的抑制剂,以抑制率为指标,采用单因素试验和正交试验对3种物质协同降糖降脂作用进行研究。结果表明,3种提取物复配质量浓度为番石榴多糖1.25 mg/mL,苹果多酚1.5 mg/mL,山楂黄酮1.5 mg/mL时,体外协同抑制α-淀粉酶和α-葡萄糖苷酶活效果较强,其协同抑制α-淀粉酶活性和α-葡萄糖苷酶的抑制率可达到88.5%和90.2%;体外抑制胰脂肪酶效果最强复配质量浓度为山楂黄酮3 mg/mL、苹果多酚1 mg/mL、番石榴多糖9 mg/mL,此条件下,抑制率为70.01%,研究结果对降糖、降脂食品的研发有一定的指导意义。

苹果多酚的提取工艺及其对油脂的抗氧化作用

对苹果多酚的提取工艺进行了研究,试验结果表明,苹果多酚的最佳提取条件为:体积分数为5 8%的乙醇,液料比为4mL :1g ,在6 2℃下提取4 5min。另外,苹果多酚对菜籽油和猪油的抗氧化性能试验表明,苹果多酚对植物油和动物油均具有较明显的抗氧化效果。对于植物油其抗氧化效果要远优于BHT ,可延长菜籽油的出厂合格期接近1倍。而对动物油的抗氧化效果虽不及BHT ,但与空白组相比仍起到了较显著的抗氧化和保鲜作用。