菜籽饼粕中多糖的氢氧化钠提取方法研究

从菜籽饼粕中提取多糖可以提高菜籽饼粕的综合利用率,本文采用氢氧化钠提取菜籽饼粕中的菜籽多糖,从浸提液浓度、提取温度、提取时间、料液比4个方面对提取率进行了考察。通过正交试验,得出了菜籽多糖氢氧化钠提取的最佳条件为浸提液浓度为1.2mol/L,提取温度为60℃、料液比为1∶20、提取时间为4h、多糖含量为7.65%。     

菜籽饼粕蛋白的提取、功能特性及其在食品中应用的研究进展

菜籽饼粕作为油菜籽榨油后的副产物,其蛋白质含量丰富、氨基酸组成均衡,是一种优质的植物蛋白资源,但长期以来主要用于饲料行业,经济效益较低。从菜籽饼粕中提取的菜籽蛋白已被证明具有良好的乳化性、凝胶性等功能特性及降血压、抗氧化等生理活性。目前,菜籽蛋白已被欧盟及FDA批准作为新食品原料,可作为人类食用的优质植物蛋白资源。本文论述了菜籽饼粕蛋白的提取方法、功能特性及其在食品中的应用现状,旨在为菜籽饼粕蛋白的进一步开发与合理应用提供理论依据及技术支撑。     

菜籽饼粕脱毒方法研究进展

对当前菜籽饼粕的脱毒方法进行了归纳总结.菜籽饼粕脱毒方法主要分为物理脱毒法、化学脱毒法、微生物脱毒法和遗传育种法4大类.想要高效利用菜籽饼粕,必须综合考虑其抗营养因子并加以脱除.     

提高菜籽饼粕利用的方法

菜籽饼粕内蛋白质含量丰富,但由于熟榨制油及饼粕内含有毒素,严重影响了其利用价值。本文提出从榨油工艺改进及饼粕脱毒途径着手,进而提高菜籽饼粕蛋白的利用,有其重大的经济价值。     

菜籽饼粕对鸡蛋的污染及其预防

芥子碱是菜籽饼粕对部分产蛋鸡鸡蛋污染的化学基础。在鸡肠道某些细菌作用下,芥子碱逐步水解为三甲胺,三甲胺不经氧化直接进入蛋黄中,使其中三甲胺含量显著增大从而产生鱼腥昧。菜籽饼粕中有多种三甲胺氧化酶抑制剂,其中最主要的为PG芥子甙的水解物5—乙烯基噁唑烷硫酮和水溶性单宁。菜籽饼粕的各种脱毒方法以及低硫甙菜籽饼粕乃至多种抗生素和硒都不能完全消除其对部分产蛋鸡鸡蛋的污染。据此笔者认为预防菜籽饼粕对鸡蛋污染的可行方法是避免用含菜籽饼粕的配合料饲喂产棕色蛋的鸡群。     

WRD—87湿法脱毒菜籽饼粕饲喂肉鸡试验

本文报告了用陕西师范大学提供的WRD—87湿法脱毒菜籽饼粕代替50％鱼粉或50％豆饼(?)喂杂交肉鸡的结果,经两个月饲喂表明:试验组较对照组(基本日粮组)增重显著,未脱毒菜籽饼粕组增重差,剖检结果证明:脱毒菜籽饼粕未引起肝、脾、甲状腺病变,而未脱毒菜籽饼粕明显引起诸脏器病变。     

菜籽饼粕中菜籽多酚的提取新工艺研究

采用酸性乙醇体系提取菜籽饼粕中的菜籽多酚,确定了提取的最佳工艺:40目的菜籽饼粕,pH为2.0的(体积分数)70%乙醇溶液,料液比(g:mL)为1:4,提取温度为40℃,提取时间为40min,分3次提取。在此条件下,菜籽饼粕中菜籽多酚的提取率达到2.09%,高于以往的丙酮提取法。     

菜籽饼粕中多肽的提取纯化及抗肿瘤活性

从菜籽饼粕中分离纯化多肽,并验证其抗肿瘤活性.采用超声-微波协同萃取法获得菜籽饼粕总蛋白,通过碱性蛋白酶水解提取菜籽饼粕总多肽,连用分子排阻色谱和反相高效液相色谱纯化获得菜籽饼粕多肽(RMP).通过对Hela细胞生长的抑制作用评价RMP的抗肿瘤活性.结果 显示:RMP由8个氨基酸组成,序列为Asp-Val-Phe-Va...     

菜籽饼粕开发研究与推广应用

菜籽饼粕作为蛋白饲料是我国南方的一大特色和优势。本文根据国内外研究成果,介绍了菜籽饼粕的饲用价值,对菜籽饼粕利用中的一些限制因素进行了分析。关于菜籽饼粕开发利用途径,重点介绍了国内外脱毒工艺技术研究的现状;在不同工艺条件下对脱毒效果和营养的影响。在当前脱毒技术还未完全过关的情况下,通过限量饲喂的方法也是可行的。     

菜籽饼粕解毒剂的功用及试验

1 菜籽饼粕解毒剂的功用和机理菜籽饼含粗蛋白30%～40%,是畜禽饲料蛋白质的重要来源之一。开发菜籽饼饲料资源在我国已有悠久的历史,通过饲喂畜禽、过腹肥田,既提高菜籽饼粕利用价值又为饲养业增加     

Exopolysaccharide Production from Lactic Acid Bacteria Isolated from Fermented Foods

Isolates of lactic acid bacteria were obtained from non-dairy fermented foods (Mettwurst salami, Prosciutto ham and black olives). Their species were identified and they were investigated for their ability to produce exopolysaccharides. A reference yoghurt culture (Streptococcus thermophilus) and an exopolysaccharide producing isolate (Leuconostoc mesenteroides - Isolate 3) were grown in mESM broth under aerobic conditions at 25°C. They produced up to 600 mg/L and 530 mg/L of exopolysaccharide, respectively. Viscosities of the final fermentation broths were much higher in comparison to the isolated exopolysaccharide solutions. The addition of whey protein concentrate (0.2% w/v) to the extracted exopolysaccharides slightly increased the viscosity of the solutions.     

米糠脂多糖提取物中分离蛋白质的研究

米糖是富含植物脂多糖的植物资源。本文就米糖脂多糖制备过程中,蛋白与脂多糖的分离方法进行了研究。结果表明,等电点沉淀法和超滤法的串联应用可充分发挥两者的分离特点,是众多分离蛋白方法中较有效的方法。     

Isolation and Properties of Starch from Wild Yam from Zimbabwe

Wild Yam (Dioscorea dumetorum) was collected during the wet as well as dry season in the bush of Zimbabwe. Starch from its tubers was isolated in behavioral conditions and properties were determined such as size of granules, content of water, amylose, phosphorus, proteins and lipids, characteristics of gelation of its gels and thermal properties (TG, DTG, DTA).     

Value added products from fermentation of sugars derived from agro-food residues

BackgroundGlobally, significant amounts of agro-food residues are generated, most of which are burned as waste disposal. Given the abundance of this biomass, it can be used as raw material for the production of biofuels and valuable chemicals through biochemical conversion. Research in this field has gained importance given concerns regarding limitation of fossil resources, environmental problems and sustainability and preference towards natural, biodegradable and environmentally friendly products. Furthermore, the accessibility of alternative substrate sources for fermentative production of these high-value products has been one of the primary goals of industrial biotechnology research in the past two decades.Scope and approachThe present review is focused in the production of high value products through microbial fermentation of sugars from agro-food residues. Research in this field is interesting due to concerns regarding limitation of fossil resources. On the one hand, for the production of these bioproducts it is important the accessibility of alternative substrate and, on the other hand, the selection of the right microorganism to obtain the desired product. For this reason, the novelty of the present work is that details all different bioproducts which can be obtained through fermentation of sugars derived from agro-food residues, describing raw materials, pretreatments, mode of operation, conditions and microorganisms used, together with the production yields.Key findings and conclusionsThe use of renewable and environmentally sustainable agro-food residues as raw material for the production of bio-based products has gained interest recently. For this purpose, the application of a suitable pretreatment to improve biomass digestibility and the optimization of biomass hydrolysis for the production of fermentable sugars is crucial to make bio-based products competitive with petroleum-based ones. The combination of pretreatments together with the employment of microorganisms tolerant to inhibitors generated during the pretreatment or able to ferment pentose sugars in hydrolysates have turned out to be interesting approaches. Regarding hydrolysis and fermentation, SHF and SSF are the predominant strategies, although CBP and SSCF have gained recognition recently. The final bioproduct cost depends on the productivity, yield per quantity of substrate, cost of raw material and the recovery method. In this way, for the commercialization of these bioproducts, some technical challenges are still needed, including the reduction of the pretreatments and enzymes costs, the design of strains with tailored capabilities, downstream processes optimization, waste treatment, etc.     

Novel peptides from dried squid head by-products obtained from snack process

The novel peptides were successfully produced with commercial protease hydrolysis (Alcalase® and Flavourzyme®) at the fixed concentration of 3%by weight of protein in substrate. The hydrolysis was performed at various hydrolysis times (0, 300, 450, 600 and 750 min) at the optimal pH and temperature. When the hydrolysis was performed until 750 min, the peptide solutions with high soluble protein content were resulted (47.58 and 42.53 mg protein per mL for Alcalase® and Flavourzyme® hydrolysis, respectively). After freeze drying, the peptide powder from Alcalase® and Flavourzyme® hydrolysis had degree of hydrolysis at 71.87% and 66.39%, respectively. Alcalase® hydrolysis provided the novel peptide fraction with DPPH scavenging, ABTS activity and ACE-inhibitory activity at 64.20%, 102.50 µg mL⁻¹ and 56.98%, respectively. This peptide fraction possessed the lowest molecular weight (m/z 807.418) as detected by MALDI-TOF/MS, and the most potent peptide sequence was Arg-Glu-Gly-Tyr-Phe-Lys which has the potential as functional ingredient in novel food, snacks and beverages.     

湛江对虾副产物酶解制备抗氧化肽

以湛江对虾加工副产物虾头为研究对象,研究虾头的酶解条件和酶解产物的抗氧化活性,选用木瓜蛋白酶和胃蛋白酶分别对虾头酶解,制备高活性的抗氧化肽。在单因素的基础上,以清除DPPH自由基为指标,研究时间、温度、加酶量、pH对酶解产物抗氧化活性的影响。结果表明,与木瓜蛋白酶相比,胃蛋白酶酶解产物的抗氧化效果更好;通过正交试验,确定胃蛋白酶酶解产物的最佳条件为温度32℃、酶解时间1 h、pH 1、加酶量为1.33×10-5kat/g(以底物计),在此条件下酶解产物的抗氧化活性最高,对DPPH自由基清除率为89.12%。     

需要向百威学什么

<正> 据中华全国商业信息中心对全国重点大型零售商场的销售统计,在去年啤酒销售排名中,百威名列第二。能有这种业绩,证明其潜力惊人。其除了品质优秀外,鲜明的品牌个性是其至关重要的因素。我们需要向百威学习:     

Production losses from mastitis: carry-over from the previous lactation

The study examined whether elevation in SCC in the second lactation was associated with reduced milk production in the third lactation. Lactation records from 10,705 Holstein cows from 770 herds were taken from the Dairy Records Processing Center at Raleigh. Cows in the data set were selected so that no SCC test in the first lactation was elevated above a linear score of 4.5 (no mastitis in the first lactation). Using actual and mature equivalent milk production in the first lactation as a baseline, effects of elevated SCC on production in the second and third lactations were examined using linear regression. The effect of high SCC during a cow's current lactation was found to be essentially the same as previously reported by other investigators. An increase in the lactation average linear score of 1.0 was associated with a decrease of approximately 200 kg of milk per lactation. Limited carry-over effect of elevated SCC during the second lactation was found in the third lactation. For third lactation milk production, the effect of increased SCC during the preceding (second) lactation was only about 20 to 30% as much as the effect of SCC increases in the third lactation.     

Exfoliation of Helicobacter pylori from gastric mucin by glycopolypeptides from buttermilk

In the human stomach, Helicobacter pylori, an ulcer pathogenic bacterium, colonizes the gastric mucosal layer primarily. The ability of glycopolypeptides (GPP) prepared from buttermilk to exfoliate H. pylori bound to gastric mucin was investigated. The GPP were prepared from buttermilk by digestion with trypsin, papain, pancreatin, bromelain, or pepsin. Helicobacter pylori ATCC 43504T and 43579 adhered more strongly to all of the GPP tested than to whole buttermilk, the soluble fraction of buttermilk, gastric mucin prepared from mouse stomach, or commercial pig gastric mucin. The GPP digested with trypsin, papain, or pancreatin were significantly more adherent. When the GPP concentration was 10 mg/mL, bound H. pylori ATCC 43504T, 43579, and 5 clinical isolates were exfoliated markedly from immobilized porcine gastric mucin following treatment with GPP digested with trypsin or pancreatin. This ability of GPP did not correlate with sialic acid content, indicating that sialic acid content is not important in the exfoliation of this microorganism. Such an ability may depend on the structure or number of sugar chains, or the position of sialic acid. We conclude that GPP promote the exfoliation of H. pylori bound to gastric mucin and prevent the de novo adherence of this microorganism. As such, GPP are a promising food material for preventing H. pylori infection.     

乌拉圭的嘉颂酒庄

没有多少葡萄酒消费者知道乌拉圭也是一个产酒国。事实上,乌拉圭是南美洲第四大葡萄酒生产商。尽管乌拉圭的葡萄酒产量仅占整个大陆的4%左右,但当你意识到,如果与邻国阿根廷和巴西对比的话,乌拉圭的面积有多么小时,那么这个"4%"着实令人印象深刻。