卵白蛋白肽复合酶法制备工艺优化及解酒效果

目的:验证卵白蛋白肽的解酒活性,提高鸡蛋产品的附加值。方法:用碱性蛋白酶和胰蛋白酶复合酶解卵白蛋白,以乙醇脱氢酶(ADH)激活率为指标,采用响应曲面法优化酶解工艺。通过检测卵白蛋白肽的总抗氧化性、水解度、氨基酸组成及相对分子质量,评估卵白蛋白肽的解酒效果。结果:最佳酶解工艺条件:酶解时间5 h,复合酶用量3 100 U/g,酶解温度50 ℃,料液比(m_卵白蛋白∶V_蒸馏水)3.5∶25 (g/mL),在此条件下得到的卵白蛋白肽ADH激活率为(22.71±0.15)%,总抗氧化能力值为(9.51±0.03) U/mL,水解度为(29.28±0.16)%。卵白蛋白肽富含谷氨酸(9.554 3%)、丙氨酸(3.863 3%)、亮氨酸(5.764 7%)等有益于提高解酒活性的氨基酸,小分子肽(＜1 000 Da)含量超过88.77%。结论:使用复合酶解法制备的卵白蛋白肽具有良好的抗氧化活性和解酒效果。     

酶解马鲛鱼下脚料制备海鲜酱工艺优化

对马鲛鱼下脚料水提液进行酶解,通过单因素及正交酶解试验,优化了马鲛鱼下脚料的酶解工艺,再利用酶解液制备海鲜调味酱,并与市售海鲜酱的感官品质进行对比分析。结果表明,马鲛鱼下脚料的最佳酶解工艺条件为：中性蛋白酶用量500 U/g,液料比（V_水∶m_下脚料）3∶1 （mL/g）,酶解温度55 ℃,pH值 7.5,酶解时间5 h,该酶解条件下酶解液中氨基酸态氮的质量浓度高达（0.325±0.004） g/100 mL。制备的海鲜酱与市售海鲜酱的口感相当,产品理化及微生物指标符合相关国家标准要求。     

鸭蛋卵清蛋白的结构、 组成分析及其功能活性研究

本研究比较了鸭蛋卵清蛋白的三种提取方法,首先采用傅里叶红外线光谱分析仪、圆二色谱和电镜分析卵清蛋白二级结构,再采用半自动氨基酸分析仪进行了营养评价,最后采用RAW 264.7细胞模型和DPPH·、ABTS+·及ORAC抗氧化模型分别探究了其免疫调节活性和抗氧化活性。实验结果表明采用pH4.50、60%饱和硫酸铵沉淀获得的蛋白总氮含量为86.75%±4.12%,蛋白得率为86.17%±2.69%。结构分析表明其中α-螺旋占15.06%,β-折叠占24.69%,β-转角占25.63%,无规则卷曲占33.83%,具有一般清蛋白的表面结构。功能活性模型表明卵清蛋白能显著提高RAW 264.7细胞上清液中NO、TNF-α、IL-6分泌量(P<0.05),具有免疫调节活性,体外抗氧化活性表明2000 μg/mL卵清蛋白,其ABTS+·清除率为57.05%、DPPH·清除率为26.12%、ORAC值为0.3148 μmol/L TE/mg,显示出有一定的抗氧化活性,为鸭蛋卵清蛋白的基础研究提供理论支撑。     

龙牙楤木多糖复合酶法提取工艺优化及抗氧化活性研究

目的：优化龙牙楤木多糖复合酶法提取工艺,提高其抗氧化活性。方法：以纤维素酶、果胶酶和木瓜蛋白酶为复合酶提取龙牙楤木多糖,以酶解温度、酶解时间、料液比为自变量,通过Box-Behnken中心组合法设计三因素三水平试验方案,并通过测定自由基清除能力考察龙牙楤木多糖的抗氧化活性。结果：复合酶法提取龙牙楤木多糖的最佳工艺条件为：酶解温度54 ℃,酶解时间160 min,料液比（m_{龙牙楤木粗粉}∶V_纯化水）1∶31 （g/mL）,此条件下龙牙楤木多糖平均提取率为（10.68±0.05）%,与模型预测值10.78%接近;抗氧化试验表明龙牙楤木多糖对DPPH自由基及羟基自由基的IC₅₀值分别为2.00,3.05 mg/mL,且清除作用均随多糖质量浓度的增大而升高,清除率最大值分别为78.10%,70.10%。结论：该复合酶法工艺条件提高了龙牙楤木多糖提取率;龙牙楤木多糖具有良好的抗氧化活性。     

Ag-HA/TiO2抗菌剂的制备及在大黄鱼中的应用

为探究载银羟基磷灰石（AgHAp）/二氧化钛（Ag-HA/TiO ₂ ）抗菌剂在水产品中的应用，研究了Ag-HA/TiO ₂ 的结构表征。选取大肠杆菌和金黄色葡萄球菌为测试菌株，比较了AgHAp和Ag-HA/TiO ₂ 的抗菌性能，并初步判断Ag-HA/TiO ₂ 对水产品特定腐败菌荧光假单胞菌和腐败希瓦氏菌（SSOs）的抗菌率，在此基础上进行了实际应用。测试了抗菌液质量浓度和浸泡时间对大黄鱼的微生物和一级鲜肉标准的影响，结果表明：Ag-HA/TiO ₂ 负载二氧化钛、降低一半银质量分数后，结构晶形基本不变，Ag-HA/TiO ₂ 对大肠杆菌和金黄色葡萄球菌的抗菌率为100 %，比银质量分数为3.00%的AgHAp要好，且对该2种菌的最小抑菌质量浓度均为312.5 μg/mL；10 mg/mL Ag-HA/TiO ₂ 对SSOs在0.5 h时抑菌率分别为（97.58±3.43）%和100%，作用时间为1 h和1.5 h时均为100%；Ag-HA/TiO ₂ 浸泡液质量浓度越高或大黄鱼浸泡时间越长，对大黄鱼中细菌生长越有明显的抑制效果，且延长大黄鱼一级鲜肉标准的货架期。该研究结果证明，Ag-HA/TiO2抗菌具有高效性，有望成为一种理想的水产抗菌材料。     

不同蛋白酶海参酶解液的制备及其体外免疫调节活性

以海参体壁为原料,采用5种商业用酶（中性蛋白酶、碱性蛋白酶、胰蛋白酶、木瓜蛋白酶、胃蛋白酶）对其进行酶解,测定酶解液的水解度和分子量分布,并重点分析分子量小于3 kDa超滤组分的氨基酸组成、结构特性及其对巨噬细胞的免疫调节活性。结果表明：中性蛋白酶对海参体壁的水解能力最高,反应300 min水解度达17.18% ;中性蛋白酶酶解液中小于3 kDa超滤组分（SCH-N-I）占96.33% ,必需氨基酸高达89.52 mg/g,高于其余4种蛋白酶酶解液。紫外光谱和荧光光谱结果显示,中性蛋白酶酶解液超滤组分SCH-N-I较其它酶解液超滤组分具有较高的表面疏水性、紫外吸光度和内源荧光强度,且最大紫外吸收波长和最大荧光峰向高波长方向偏移,表明其可能具有更高的免疫生物活性。RAW264.7巨噬细胞免疫活性实验结果显示,当SCH-N-I浓度为200 μg/mL时,巨噬细胞表现出良好的存活率[（121.79±4.98）% ]及较高的吞噬力（0.107 7±0.001 0）和NO释放量[（15.39±0.33）μmol/L];SCH-N-I的免疫活性高于其他4种蛋白酶酶解液超滤组分。     

鸡蛋壳膜多肽酶解工艺及抗氧化活性研究

试验以鸡蛋壳膜为原料,通过酶解法制备小分子肽,并对其生物活性进行研究。以水解度为评价指标,通过单因素试验确定蛋白酶种类、酶解时间、料液比以及酶添加量等因素对壳膜多肽水解度的影响,并通过响应面设计（Box-Behnken design,BBD）对酶解条件进行三因素三水平优化;通过高效凝胶过滤色谱测定酶解后壳膜多肽分子量的分布情况,并测定壳膜多肽对DPPH·、ABTS+·、·OH、O2-·的清除能力。结果表明,最佳酶解工艺条件为碱性蛋白酶（AP-200a）,酶添加量2.4%,料液比1∶9.5（g/mL）,酶解时间5 h;在此条件下,壳膜多肽水解度为27.15%,水解后相对分子质量小于1 000 Da的小分子肽所占比例为90.9%;且壳膜多肽对DPPH·、ABTS+·的清除率分别为（93.03±0.51）%、（94.53±0.92）%,与 VC的效果相当;但对·OH 和 O2-·的清除率分别为（43.33±1.10）%和（53.40±0.70）%。因此,通过该法酶解得到的壳膜多肽中小分子肽占比较高,易被人体消化吸收,且具有一定抗氧化活性。     

虾壳源蛋白水解物降糖降脂活性评价及肽序分析

目的：采用酶解法制备克氏原螯虾壳蛋白水解物（Procambarus clarkii shell protein hydrolysates,PCSPHs）,并分析其体外降糖降脂活性及肽序。方法：分别采用胃蛋白酶、碱性蛋白酶、胰蛋白酶、风味蛋白酶和木瓜蛋白酶水解制备不同虾壳蛋白水解物,分析其体外降糖降脂活性和肽序列;运用Peptide Ranker及BIOPEP-UWM网站在线分析,再以核受体PPARγ配体结合区域的晶体结构作为靶点,使用Autodock vina进行分子对接模拟,获得具有潜在降糖降脂活性的虾壳肽。结果：胃蛋白酶水解物（PEP-PCSPHs）对α-淀粉酶和α-葡萄糖苷酶活性具有较强的抑制作用,IC₅₀值分别为（5.42±0.05）,（7.11±1.01） mg/mL;胰蛋白酶水解物（TRY-PCSPHs）对胰脂肪酶活性具有最强的抑制能力,IC₅₀值为（4.71±1.12） mg/mL,且对甘氨胆酸钠表现出最好的体外结合效果。此外,经质谱鉴定PEP-PCSPHs和TRY-PCSPHs中分别得到3 391,2 086条肽序;通过在线网站预测和分子对接筛选出多条均能与PPARγ结合的降糖降脂虾壳活性肽（PCSAPs）。结论：酶解克氏原螯虾壳制备的虾壳蛋白水解物具有潜在的降糖降脂活性,可能改善糖脂代谢紊乱。     

酶解—膜分离耦合连续制备抗氧化性小分子透明质酸

目的：构建一种酶解—膜分离耦合的方法用来提高小分子透明质酸的生产效率。方法：利用酶生物反应罐与平板式聚醚砜超滤膜分离组件组成的连续式酶解—膜分离耦合反应体系。以膜通量、膜污染、透过液透明质酸质量浓度、产率为评价指标，系统地考察各因素对酶膜耦合体系内两种不同相对分子质量透明质酸分离效果的影响，并以产率为指标进一步通过正交试验优化酶膜耦合反应的工艺参数。结果：酶膜耦合反应体系制备小分子透明质酸的最优工艺参数为搅拌速度200 r/min、跨膜压力0.15 mPa、酶解时间4.0 h、加酶量5 g/100 g。该条件下可以快速制备并分离出两种不同相对分子质量（M_r）的小分子透明质酸，实现一步法同时制备M_r在1万～5万的低相对分子质量透明质酸（LMW-HA）和M_r＜3 000的透明质酸寡糖（O-HA），且这两种不同相对分子质量透明质酸均具有清除DPPH自由基和羟自由基的能力。结论：酶解—膜分离耦合法可以连续同步生产具有不同相对分子质量和一定抗氧化性的LMW-HA和O-HA。     

8种食用菌蛋白及其酶解产物抗氧化活性研究

目的:综合评价8种食用菌(香菇、平菇、杏鲍菇、红菇、大球盖菇、草菇、白玉菇、蟹味菇)蛋白及其酶解产物的抗氧化活性。方法:采用碱性蛋白酶对8种食用菌蛋白进行酶解,以DPPH自由基清除活性、ABTS自由基清除活性、Fe2+螯合率和还原力为指标,对8种食用菌蛋白及其碱性蛋白酶酶解产物的抗氧化活性进行评价。结果:SDS-PAGE电泳图谱显示,碱性蛋白酶可以有效地将蛋白质水解为小分子的肽和氨基酸;草菇蛋白酶解产物的抗氧化活性最高,DPPH自由基清除能力为(5 140.45±5.35) μg Trolox/g,ABTS自由基清除能力为(6.97±0.27) mmol Trolox/L,Fe²⁺螯合率为(79.86±0.45)%,还原力为0.350±0.001,且含有8种必需氨基酸(230.43±5.35) mg/g和较高抗氧化活性的疏水性氨基酸(209.95±4.95) mg/g、负电荷氨基酸(115.89±2.32) mg/g和芳香族氨基酸(57.86±1.74) mg/g。结论:草菇碱性蛋白酶解产物有较好的抗氧化活性且富含必需氨基酸、疏水性氨基酸、负电荷氨基酸及芳香族氨基酸。     

The effect of in vitro gastrointestinal simulation on bioactivities of kefir

Kefir is a fermented milk beverage and known to have positive effects on gut microbial diversity and human health. In this study, digested and undigested kefir samples were compared for changes in their antihypertensive, antidiabetic, antioxidant and antimicrobial activities. Results showed that the amount of total phenolic substances, 2,2-diphenyl-1-picrylhydrazyl radical scavenging (DPPH) activity, and the angiotensin-converting enzyme inhibitor (ACE-I) activity increased from 43.76 ± 0.005 mg gallic acid equivalents (GAE)/L, 4.20 ± 0.55%, and 9.91 ± 3.90% in undigested kefir to 668.16 ± 3.332 mg GAE/L, 63.06 ± 0.64%, and 98.88 ± 0.42% in digested kefir, respectively. While the dipeptidyl peptidase IV-inhibitory (DPPIV-I) activity of undigested kefir increased by 19.11 ± 7.35% after digestion, the optical density of the ferric-reducing antioxidant power (FRAP) decreased from 1.188 ± 0.05 to 0.278 ± 0.009, and the protein amount decreased from 101.4 mg L⁻¹ to 12.42 mg L⁻¹ in digested kefir. No antimicrobial effect was observed in undigested kefir, whereas, digested kefir samples were active, but only against Escherichia coli. These results show that the gastrointestinal digestion processes of kefir generally increase the number of bioactive molecules, and the digestion process must be taken into account to determine the biological capability of foods.     

驴乳的营养成分及其保健作用的研究进展

驴乳作为营养品广泛使用已有数千年的历史,因其含有多种营养成分和生物活性,是婴幼儿、老年及体弱者补充营养物质的重要来源.该文综述驴乳的营养成分和抗菌、抗炎、抗氧化、抗过敏等保健作用,以期为驴乳产业提供新的方向和理论支持.     

Antioxidant, antimicrobial, and anticancer activity of 3 Umbilicaria species

Abstract: The aim of this study is to investigate in vitro antioxidant, antimicrobial, and anticancer activity of the acetone extracts of the lichens Umbilicaria crustulosa, U. cylindrica, and U. polyphylla. Antioxidant activity was evaluated by 5 separate methods: free radical scavenging, superoxide anion radical scavenging, reducing power, determination of total phenolic compounds, and determination of total flavonoid content. Of the lichens tested, U. polyphylla had largest free radical scavenging activity (72.79% inhibition at a concentration of 1 mg/mL), which was similar as standard antioxidants in the same concentration. Moreover, the tested extracts had effective reducing power and superoxide anion radical scavenging. Total content of phenol and flavonoid in extracts was determined as pyrocatechol equivalent, and as rutin equivalent, respectively. The strong relationships between total phenolic and flavonoid contents and the antioxidant effect of tested extracts were observed. The antimicrobial activity was estimated by determination of the minimal inhibitory concentration by the broth microdilution method. The most active was extract of U. polyphylla with minimum inhibitory concentration values ranging from 1.56 to 12.5 mg/mL. Anticancer activity was tested against FemX (human melanoma) and LS174 (human colon carcinoma) cell lines using MTT method. All extracts were found to be strong anticancer activity toward both cell lines with IC₅₀ values ranging from 28.45 to 97.82 μg/mL. The present study shows that tested lichen extracts demonstrated a strong antioxidant, antimicrobial, and anticancer effects. That suggests that lichens may be used as possible natural antioxidant, antimicrobial, and anticancer agents.     

Antioxidant, antimicrobial and anticancer activities of three Parmelia species

BACKGROUND: Lichens are symbiotic organisms consisting of algae and fungi. They are used for human and animal nutrition and in the production of colours, perfumes and alcohol. Lichens have also been used in traditional medicine to treat diseases such as jaundice, pulmonary, stomach and cranial diseases. In this study the acetone extracts of three lichens, Parmelia caperata, Parmelia sulcata and Parmelia saxatilis, were tested for their antioxidant, antimicrobial and anticancer potential. RESULTS: Of the lichens tested, P. saxatilis had the highest free radical‐scavenging activity (55.3% inhibition). Moreover, all tested extracts showed effective reducing power and superoxide anion radical scavenging. Strong relationships between total phenolic and flavonoid contents and antioxidant effects of the tested extracts were observed. The extract of P. sulcata was most active in terms of antimicrobial ability, with minimum inhibitory concentration values ranging from 0.78 to 12.5 mg L^?1. All extracts were found to have strong anticancer activity, with IC₅₀ values ranging from 9.55 to 22.95 µg mL^?1. CONCLUSION: The present study showed that the tested lichen extracts exhibited strong antioxidant, antimicrobial and anticancer effects. This suggests that lichens may be used as possible natural antioxidant, antimicrobial and anticancer agents. Copyright © 2012 Society of Chemical Industry     

Antioxidant and antimicrobial activities of propolis from several regions of Korea

Biological activities of different propolis extracts in Korea were examined for the evaluation of quality comparison with that from Brazil (BZ). Total polyphenol and flavonoid contents of propolis extracts from Yeosu (YS) and Cheorwon (CW), whose values were higher than BZ, were also shown to be more aboudant. The extracts of YS and CW also showed strong antioxidant activities, using the linoleic acid peroxidation and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging activity. However, the extract from BZ had less active antioxidant activity on linoleic acid peroxidation and DPPH free radical-scavenging activity of less than 70% than other extracts. The DPPH free radical-scavenging activity seems to relate with the antioxidant activity of linoleic acid peroxidation. The propolis with antioxidant activity also had DPPH free radical-scavenging activity. The extracts of YS and CW had effective antimicrobial activities on Staphilococcus aureus, Bacillus subtilis, Salmonella typhimurium and Candida albicans. Strong antioxidant, radical-scavenging and antimicrobial activities of YS and CW seemed to relate with high values, total polyphenol, and flavonoid contents.     

Antioxidant,Antibacterial, and Antiproliferative Activities of Free and Bound Phenolics from Peel and Flesh of Fuji Apple

This study was conducted to investigate the antioxidant, antibacterial, and antiproliferative activities of flesh free (FF), flesh bound (FB), peel free (PF), and peel bound (PB) phenolics from Fuji apple. The PB, which had highest total phenolic contents (126.15 ± 2.41 mg/100 g wet weight) and lowest total carbohydrate contents (34.68 ± 2.78 mg/100 g wet weight), showed the strongest 2,2’‐azinobis‐(3‐ethylbenthiazoline‐6‐sulphonate) (ABTS) radical scavenging activity (EC₅₀ = 0.36 ± 0.02 mg/mL), 1,1‐diphenyl‐2‐picryhydrazyl (DPPH) radical scavenging activity (EC₅₀ = 0.26 ± 0.01 mg/mL), and ferric reducing antioxidant power (Ferric reducing antioxidant power; EC₅₀ = 0.19 ± 0.02 mg/mL) compared with those of FF, FB, and PF. The PB also showed the strongest antibacterial activities on Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes and it also showed the highest antiproliferative effects on Caco‐2 human colonic cancer cell (EC₅₀ = 1.44 ± 0.01 mg/mL) and Hela human cervical cell (EC₅₀ = 2.81 ± 0.01 mg/mL). Both free and bound phenolics from Fuji apple showed good antioxidant, antibacterial, and antiproliferative activities in our study, and bound phenolics had significantly higher activities compared with those of free phenolics.     

4种海南诺丽果内生细菌多样性及其关键生物活性研究

诺丽果富含生物活性成分,具有较强抑菌性和抗氧化能力。为探讨海南诺丽果中内生菌多样性的区别及其关键活性与多样性之间的联系,通过高通量测序技术(HTS),从4种诺丽果(长果标号为L、圆果标号为R、连体果标号为C、大溪地诺丽果标号为T)中发现了它们共同的优势菌属为短波单胞菌属(Brevundimonas)、泛菌属(Pantoea)和芽孢杆菌属(Bacillus),并测定内生细菌抑菌性,对具有抑菌活性的内生细菌进行总抗氧化性测定,发现具有抑菌性的诺丽果内生细菌均具有抗氧化性,抗氧化值在3.07～20.78U·mL-1,同时内生细菌的抗氧化性和抑菌活性呈正相关性。挑选4个品种诺丽果中2种关键活性较高的内生菌8株,进行16S rDNA和gyrA分子生物学鉴定,鉴定结果均为芽孢杆菌属(Bacillus),并分别属于枯草芽孢杆菌(Bacillus subtilis)、摩加夫芽孢杆菌(Bacillus mojavensis)和短小芽孢杆菌(Bacillus pumilus)。研究结果从微生物学角度比较了不同品种诺丽果内生细菌群落多样性差异,并探讨了内生细菌功能性之间以及与内生群落之间的关联,证实了植物-微生物相互作用学说。希望研究可为今后研究内生菌和宿主功能的协调性和统一性提供帮助,为具有特定功能的诺丽果内生菌的筛选应用提供理论基础,为内生菌在食品工业中的应用及植物与微生物互作研究提供更多思路。     

红参浓缩液对小鼠的抗氧化、免疫调节及降血糖作用

该研究通过建立衰老小鼠模型和II型糖尿病小鼠模型,对比不同剂量的红参浓缩液对小鼠体内抗氧化、免疫及降血糖活性影响。实验发现：与模型组相比,红参浓缩液给药组显著降低丙二醛含量（MDA）、空腹血糖（FBG）和口服葡萄糖耐量（OGTT）血糖曲线下面积（AUC）并且显著提高羟自由基清除率（•OH）、总超氧化物歧化酶（T-SOD）、谷胱甘肽过氧化氢酶（GSH-Px）和过氧化氢酶（CAT）活力和免疫球蛋白G（Ig G）、免疫球蛋白M（Ig M）、白细胞介素4（IL-4）和γ干扰素（IFN-γ）含量（P<0.05）,明显改善脾脏损害。以上结果表明一定浓度的红参浓缩液可以延缓衰老、提高衰老模型小鼠的免疫力,增强II型糖尿病模型小鼠的葡萄糖耐受力,具有降血糖的效果。     

姜黄素的抗氧化及抗肿瘤活性研究

本文采用分光光度法测定姜黄素对ABTS和DPPH自由基的清除能力;运用AAPH诱导红细胞氧化性溶血考察姜黄素对AAPH诱导人血红细胞损伤的抑制作用。通过MTT方法考察姜黄素对A375恶性黑色素瘤生长状态的影响,并用流式细胞仪检测细胞凋亡数量;运用Western blot测定姜黄素对JNK和Akt蛋白表达的影响。结果表明,姜黄素对DPPH和ABTS自由基具有较好的清除能力,呈浓度和时间依赖性;同时,姜黄素能有效抑制AAPH诱导红细胞溶血,当姜黄素为40μM时,溶血抑制率达到52.78±1.03%。MTT结果表明,随着姜黄素浓度的升高,A375细胞存活率逐渐下降,当姜黄素为40μM,A375的细胞存活率仅为21.50±1.60%。流式分析发现,随着姜黄素浓度的提高,细胞凋亡峰(Sub G1)的含量逐渐增加。当姜黄素为40μM时,细胞内Sub G1峰的含量达到了63.30%。进一步Western blot分析发现姜黄素诱导A375细胞凋亡与上调JNK磷酸化的水平和下调AKt磷酸化的水平有关。     

Antiproliferative and antibacterial activity of extracts of Ganoderma strains grown in vitro

Food Science and Biotechnology - In this bioprospecting study the biological activities of extracts of the in vitro culture of Ganoderma Mexican strains were evaluated. The extracts were tested by...