透明质酸的特性及在食品中的应用

介绍了透明质酸的特性,阐述了透明质酸对于皮肤的重要性.通过食用透明质酸保健食品,可以达到改善皮肤.延缓衰老的效果.     

透明质酸在美容化妆品方面的应用

本文结合透明质酸的结构特性,阐述了透明质酸在化妆品中的保湿、抗皱、防晒等作用,以及通过注射、食用透明质酸达到美容、延缓衰老的目的 .     

水生生物来源透明质酸的生化特性及其制备的研究进展

透明质酸因其独特的生理生化特性在食品、医药及化妆品等领域得到广泛应用,本文论述了来源于水生生物透明质酸的基本特性以及提取纯化方法,为其部分取代陆生生物透明质酸及其在食品、医药工业中的利用提供了理论基础,并对水产透明质酸进一步的应用进行了展望.     

酶法提取鸡蛋壳膜中透明质酸的研究

对酶法提取鸡蛋壳膜中透明质酸的工艺进行了研究,通过单因素试验和正交试验考察了酶解温度、pH、酶用量、料液比和酶解时间对透明质酸提取量影响,确定了胰蛋白酶提取透明质酸的最佳工艺条件为温度50℃,pH为8.5,酶用量为8 000 U,料液比1∶40,提取时间7 h.在此条件下,蛋壳膜中透明质酸的提取量为13.294 mg/g.     

发酵液中提取透明质酸的研究进展

从发酵液中分离提纯透明质酸是发酵法生产透明质酸的关键步骤之一,文中综述了国内外研究从发酵液中提取透明质酸的各种方法以及发展前景.     

透明质酸钠排除致畸性的试验

目的 排除透明质酸钠的致畸性,探讨其食用安全性.方法 依据GB15l93-2003<食品安全性毒理学评价程序和方法>的规定进行试验.结果 透明质酸钠灌胃孕鼠,孕鼠生长正常,未见透明质酸钠引起的母体毒性、胚胎毒性及胎鼠骨骼发育迟缓,未见致畸作用.结论 透明质酸钠无致畸作用.     

酶法制备透明质酸寡糖及其透皮吸收活性研究

为研究透明质酸寡糖的透皮吸收活性,采用透明质酸裂解酶对透明质酸进行酶法降解,制备透明质酸寡糖,通过红外光谱与质谱对透明质酸寡糖进行分析,并对其吸湿性能、体表保湿性能和透皮吸收性能进行评价.结果显示,透明质酸裂解酶酶解制备透明质酸寡糖的最适底物浓度为1％,最适加酶量为3.0 U/mg,酶解制备透明质酸寡糖基本没有基团脱落...     

透明质酸对烟用香料的定香效果

为考察透明质酸在加香过程中对香料单体定香效果的影响,采用同时蒸馏萃取、气相色谱-质谱( GC/MS)和内标法定量考察了不添加透明质酸只加香料单体、同时添加透明质酸和香料单体、先加香料单体再添加透明质酸3种不同方式下,烟丝中香料单体的持留率.结果表明:①透明质酸具有较好的定香作用,可有效提高烟丝中香料单体的持留量;②与常用保润剂丙二醇和丙三醇相比较,其定香效果优于丙二醇和丙三醇.     

透明质酸产生菌发酵条件优化

通过对于透明质酸产生菌发酵培养基,利用Placken-Burman设计及响应面试验分析了摇瓶培养基成分,确定了最适合的摇瓶发酵培养基.通过小型发酵罐的研究确定了透明质酸的发酵工艺.实验结果表明,利用响应面实验优化的培养基组分简单.透明质酸的产量达到5.23 g/L,分子量为2.0×106u.     

透明质酸钠应用于食品工业的春天——访山东福瑞达生物化工有限公司技术总监郭学平

Q:郭总,请您简单介绍一下透明质酸这种新原料? A:透明质酸这种物质,最初是1934年由美国科学家Mayer在牛眼球的玻璃体中发现的,是一种在脊椎动物细胞内广泛存在的大分子多糖类物质,一般市场上销售的产品是透明质酸的钠盐,即透明质酸钠.最近几十年来,透明质酸首先在医药领域得到了广泛的应用.     

抗真菌乳酸菌研究

食品安全是近年来公众关注的焦点,常规的食品防腐剂由于其可能的致癌致畸副作用,促使人们寻找可替代的天然安全防腐剂。乳酸菌具有充当天然防腐剂的潜质和优势,其抗真菌研究是当前研究的热点。人们经过研究发现乳酸菌可以产生有机酸、肽类及脂肪酸等抗真菌类物质。本文就当前抗真菌乳酸菌研究进行综述,对不同抗真菌物质进行详细阐述,并对后续研究进行展望。     

Serum concentrations of 11 polyfluoroalkyl compounds in the u.s. population: data from the national health and nutrition examination survey (NHANES)

We measured the concentrations of 11 polyfluoroalkyl compounds (PFCs), including perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorohexane sulfonic acid (PFHxS) in 1562 serum samples collected from a representative U.S. population 12 years of age and older in the 1999-2000 National Health and Nutrition Examination Survey. Participants represented both sexes, three race/ethnicities (non-Hispanic blacks, non-Hispanic whites, and Mexican-Americans), and four age categories (12-19 years, 20-39 years, 40-59 years, and 60 years and older). PFCs were extracted from 100 microL of serum using on-line solid-phase extraction coupled to isotope dilution-high performance liquid chromatography-tandem mass spectrometry; limits of detection ranged from 0.05 to 0.2 ng/ mL. PFOS, PFOA, PFHxS, and perfluorooctane sulfonamide were detected in all samples analyzed; 2-(N-ethyl-perfluorooctane sulfonamido) acetic acid, 2-(N-methyl-perfluorooctane sulfonamido) acetic acid, and perfluorononanoic acid were detected in more than 90% of samples, which suggests prevalent exposures to several PFCs in the U.S. population. The concentrations of most PFCs were similar regardless of the participants' ages but were higher in males than in females. Mexican Americans had lower concentrations than non-Hispanic blacks and non-Hispanic whites, whose concentrations were similar. Higher education was associated with higher concentrations of PFOS and PFOA. These data will serve as a nationally representative baseline of the U.S. population's exposure to PFCs to which other populations can be compared, and will play an important role in public health by helping set research priorities, ranging from health effects studies to defining sources and pathways of exposure.     

Characterizing the composition of underarm and forearm skin using confocal raman spectroscopy

Many studies have reported differences in skin composition as a function of body site and age. However, rarely has axilla (underarm) skin been included in these studies. This report highlights the results of a clinical study where confocal Raman spectroscopy was used to assess the differences between underarm and volar forearm skin. In the reported study, the concentration of natural moisturizing factor (NMF), urea, lactic acid, cholesterol, trans urocanic acid (t-UCA) and ceramide 3 (N-octadecanoyl-phytosphingosine) was evaluated as a function of depth, body site (underarm vs. forearm) and age. Two age groups of women were included: (i) between 20 and 30 years and (ii) older than 55 years (post-menopause). The levels of cholesterol, ceramide 3 and lactic acid were highest in the underarm regardless of the age group whereas the forearm contained higher amounts of NMF. Ceramide 3, urea and lactic acid were significantly lower for women 55 years or older in the underarm. No age-related differences were detected within the forearm site..     

The influence of ascorbic acid on the composition, colour and flavour properties of a Riesling and a wooded Chardonnay wine during five years' storage

This paper presents the results from an investigation to assess the development of a Riesling and a wooded Chardonnay wine over five years. The wines were bottled either with or without added ascorbic acid and stored under controlled temperature and humidity conditions. Ascorbic acid addition to wine at bottling had little effect on wine aroma and flavour when the wines in this study had been in bottle for 6 months or less. For both wines, at bottle storage times of 3 years or more, addition of ascorbic acid at bottling resulted in wines with no difference in aroma or less oxidised and/or more fresh fruity aromas, even if all the ascorbic acid had been depleted at the time of assessment, compared to wines without addition of ascorbic acid at bottling. In terms of colour, for the Chardonnay wines, the effect of ascorbic acid addition at bottling assessed between two weeks and two years after bottling suggested that wines without addition were browner and had more overall colour intensity. For the Riesling wines, ascorbic acid addition had no significant effect on brownness and overall colour intensity although the Riesling wines with ascorbic acid were generally higher in yellow colour. The A₄₂₀ measurements, which are widely used to estimate the brown colour of wines, did not always appear to correlate with the brown scores obtained by visual assessment or colour measures by CIELAB when wines with and without ascorbic acid addition were compared together. For both wines, after three and five years storage, the concentration of the antioxidant sulfur dioxide was either little different or else slightly(statistically significantly) higher in wines to which ascorbic acid was added at bottling than those without addition.     

连作烟田土壤根系分泌物的变化和分解

为阐明烟田土壤中根系分泌物的变化规律及确定具有化感作用的根系分泌物种类,研究分析了种烟1年、连作2年和连作3年0~20 cm、20~40 cm烟田土壤中根系分泌物的含量变化,并通过室内试验研究了烟草根系分泌物的分解转化。结果表明：（1）烟田土壤中含量较高的根系分泌物种类有苯甲酸、4-羟基苯乙酸、3-甲氧基-4-羟基苯乙酸和邻苯二甲酸二辛酯,其中4-羟基苯乙酸含量最高,含量较低的种类有4-羟基丁酸和甘油;（2）羟基丁酸、3-甲基-2-羟基丁酸、4-羟基丁酸、肉桂酸、油酸、硬脂酸酰胺和烟碱对烟草无直接化感作用;（3）室内试验表明,肉桂酸、3-甲氧基-4-羟基苯乙酸、邻苯二甲酸、3-羟基苯甲酸、邻苯二甲酸二辛酯、4-羟基苯乙酸和肉豆蔻酸的分解转化率均小于50%;（4）初步判定具有化感作用的根系分泌物种类包括：苯甲酸、3-羟基苯甲酸、4-羟基苯甲酸、月桂酸、邻苯二甲酸、3-甲氧基-4-羟基苯乙酸、3,4-二羟基苯甲酸、肉豆蔻酸、棕榈酸、9,12-十八碳二烯酸、苯丙酸、东良菪素、肉桂酸、邻苯二甲酸二辛酯和4-羟基苯乙酸。     

不同陈酿年份市售山西老陈醋理化指标、风味和功能成分的比较

为了比较市售山西老陈醋（SAV）的品质差异,对不同陈酿年份山西老陈醋样品（陈酿1年（SAV1-1～SAV1-3）、陈酿3年（SAV3-1～SAV3-3）、陈酿5年（SAV5-1～SAV5-3）、陈酿6年（SAV6-1～SAV6-3）、陈酿8年（SAV8-1～SAV8-3）、陈酿10年（SAV10-1～SAV10-3））的理化指标、风味及功能物质进行检测。结果表明,陈酿年份越高,山西老陈醋中的pH、总酸、总酯、还原糖、可溶性固形物、氨基酸态氮、有机酸、大部分氨基酸及总多酚、总黄酮、川芎嗪和乙偶姻等功能物质含量越高,陈酿10年SAV的总酸、总酯、还原糖及氨基酸态氮平均含量最高,分别为8.40 g/100 mL、3.64 g/100 mL、3.91 g/100 mL、0.54 g/100 mL,其中有12种氨基酸的平均含量>0.5 mg/mL,SAV10-2样品中有机酸总量最高,为7.02 g/100 mL。总多酚、总黄酮、川芎嗪均在陈酿8年的醋样中平均含量最高,分别为197.96 mg/100 mL、172.04 mg/100 g、96.89 mg/L。     

Sherry wine vinegars: phenolic composition changes during aging

Production of Sherry wine vinegar encompasses a variable period of aging in wood. Changes in phenolic compounds during Sherry vinegar aging were studied. Samples were divided according to their aging period in wood (less than 2 years, more than 2 years) and phenolic compounds determined in a total of 38 samples by means of HPLC and Photodiode Array Detection. Results of Multiple Analysis of Variance (MANOVA) confirms that there were significant differences among both groups. Good recalling rates were achieved in both Linear Discriminant Analysis LDA (mean=92.9%) and Artificial Neural Networks trained by Back Propagation (BPANN) (mean=90.4%) whilst prediction abilities are more discrete. Applying the forward selection of variables, six variables were selected according to the Wilks' lambda criterion: gallic acid, 5-hydroxymethylfuraldehyde, coumaroyltartaric acid glycoside, p-hydroxybenzoic acid, caffeic acid and isoquercetrin. Three of these compounds (gallic acid, hydroxymethylfuraldehyde and coumaroyltartaric acid glycoside) were shown to have an increasing trend through most aging systems.     

贮藏时间和温度对甘蓝型油菜种子活力及脂肪酸含量的影响

研究了甘蓝型油菜种子在低温和常温干燥条件下,密闭贮藏过程中种子脂肪酸组成分含量、含油量及发芽能力的变化。结果表明：随着贮藏年限增加,甘蓝型油菜种子油酸、二十碳烯酸、芥酸的含量逐渐增加,亚麻酸、亚油酸含量则逐渐下降,棕榈酸和硬脂酸含量变化不明显;在冷藏1～5年里脂肪酸成分含量变化较快,之后变化缓慢;低芥酸材料在贮藏过程中芥酸含量增加速率高于高芥酸材料。随着贮藏时间延长,种子含油量逐渐下降,含油量高的材料下降更快;种子发芽率和发芽势均下降,后者下降幅度大;在同样冷藏条件下,套帐自交的种子比开放授粉种子的发芽率和发芽势下降均快且幅度大,而常温贮藏的开放授粉种子发芽能力下降速度明显比冷藏的快,6年后发芽率几近于零。     

Influence of harvest year and harvest time on soluble solids,titrateable acid,anthocyanin content and aroma components in sour cherry <Emphasis Type="Italic">(Prunus cerasus L. cv. "Stevnsbær")</Emphasis>

Sour cherries (Prunus cerasus L.) cv "Stevnsbær" were harvested 7-10 times per year for 3 years and the quality of the fruits was evaluated by analysing soluble solids, titrateable acid, anthocyanin and aroma content. The content of soluble solids and anthocyanin showed a characteristic pattern during the harvest season with a maximum content in the middle of the harvest season. The acid content decreased in the last part of the harvest season. There were large differences in the content of soluble solids, acid and anthocyanin between years, which to some extend could be related to the weather in the 3 years with low concentrations in the cold and rainy year. The maximum soluble solid content varied from 19% to 29% within the 3 years. There were no clear tendencies in the development of aroma components during the harvest season. The four important aroma components benzaldehyde, benzyl alcohol, eugenol and vanillin showed differences from year to year and there was a tendency to low concentrations in the cold and rainy year.     

基于PLFA分析不同窖龄窖泥微生物群落结构

该试验采用磷脂脂肪酸（PLFA）生物标记法对两种不同窖龄窖泥（30年、100年）微生物群落特征进行了研究。结果表明,100年窖龄窖泥微生物群落多样性高于30年的。对两种不同窖龄窖泥各类型的微生物结构研究发现,100年窖龄窖泥各类型的微生物含量均高于30年窖龄窖泥的,并且在两种不同窖龄窖泥中细菌的含量与丰度较其他类型微生物高,表明细菌是窖泥优势菌群。对两种不同窖龄窖泥磷脂脂肪酸含量进行主成分分析发现,30年窖龄窖泥的主要变异菌群是细菌,100年窖龄窖泥的主要变异菌群是细菌与真菌。