副干酪乳杆菌K56调节肠道菌群及润肠通便功能研究

目的:参考保健食品检验与技术评价规范(2003版)中关于调节肠道菌群及通便功能动物实验评价方法评价副干酪乳杆菌调节肠道菌群及润肠通便功能。方法:分别以0.000867、0.00867、0.0867、0.867、8.67 mg/kg灌胃给予副干酪乳杆菌K56菌株(实验室检测菌株规格为1.5×1011 CFU/g),检测小鼠干预14 d前后双歧杆菌、乳杆菌、肠杆菌、肠球菌、产气荚膜梭菌含量,并测定干预30 d后小肠墨汁推进率、首粒黑便时间、排黑便粒数及重量,评价副干酪乳杆菌对小鼠肠道菌群及排便的影响。结果:干预14 d前后比较,各组小鼠粪便双歧杆菌、乳杆菌、产气荚膜梭菌均显著增加(P<0.05),而肠杆菌和肠球菌无显著变化(P>0.05);与对照组比较,以0.00867、0.0867、0.867 mg/kg剂量的K56干预后,小鼠肠道内双歧杆菌及乳杆菌数量显著增加(P<0.05),0.000867、0.00867、0.867 mg/kg剂量的K56干预后产气荚膜梭菌含量显著降低(P<0.05);与模型组比较,0.00867、0.867、8.67 mg/kg剂量组干预小鼠墨汁推进率显著增高(P<0.05),0.0867、0.867 mg/kg剂量组小鼠排黑便粒数与重量显著增加(P<0.05),但各剂量组对小鼠首粒黑便时间与模型对照组无显著性差异(P>0.05)。结论:副干酪乳杆菌K56菌株具有调节肠道菌群和润肠通便的作用,调节肠道菌群最佳剂量为0.0867 mg/kg(对应人体剂量1.0×108 CFU/d),润肠通便最低有效剂量为0.867 mg/kg(对应人体剂量为1.0×109 CFU/d)。     

蔓菁对小鼠肠道菌群的影响

目的:探究不同剂量蔓菁对小鼠粪样中肠道菌群和短链脂肪酸的影响。方法:选取BalB/C雄性小鼠(18~22 g)48只按体重随机分为对照组、低剂量组、中剂量组、高剂量组4组,三个剂量组分别饲喂不同剂量(1、2、4 g/kg·BW·d)的蔓菁粉,对照组正常喂养,连续干预14 d,分别在干预第0 d、第7 d、第14 d称重并无菌收集新鲜粪样。采用平板计数法检测肠道菌群数量,气相色谱-质谱联用法检测短链脂肪酸的含量,并用SPSS 21.0对结果进行数据分析。结果:蔓菁可增加肠道益生菌乳酸杆菌、双歧杆菌和中性菌肠杆菌的数量(p<0.05),减少中性菌肠球菌和致病菌产气荚膜梭菌的数量(p<0.05),中剂量(2 g/kg·BW·d)作用最为明显,且肠杆菌数量增加幅度低于乳酸杆菌和双歧杆菌增加幅度。蔓菁还可增加肠道乙酸、丙酸、正丁酸、异丁酸的含量(p<0.05),提高短链脂肪酸总含量,高剂量(4 g/kg·BW·d)作用最为明显。结论:蔓菁可促进小鼠肠道有益菌的增殖,抑制致病菌的增殖;蔓菁可促进小鼠肠道短链脂肪酸的产生。     

低聚异麦芽糖调节肠道菌群及润肠通便作用的研究

为研究体外检测低聚异麦芽糖对长双歧杆菌和嗜酸乳杆菌生长的影响及低聚异麦芽糖对BALB/c小鼠肠道菌群影响以及对便秘小鼠润肠通便的作用。采用不同浓度低聚异麦芽糖与葡萄糖作为培养基中的碳源,与碳源为葡萄糖比较,检测不同浓度低聚异麦芽糖条件下长双歧杆菌和嗜酸乳杆菌的生长情况。体内实验以BALB/c雌性小鼠为实验对象,连续给予小鼠高剂量(1.0 g/(kg·bw))、低剂量(0.5 g/(kg·bw))的低聚异麦芽糖14 d后,测定小鼠粪便中双歧杆菌、乳杆菌、肠杆菌、肠球菌的含量;连续给予小鼠高、低剂量的低聚异麦芽糖21 d后,以复方地芬诺酯建立小鼠便秘模型,测定给予低聚异麦芽糖后便秘小鼠的排首黑便时间、6 h内黑便重量及小肠推进率。得到在体外实验中,与碳源为葡萄糖相比,碳源为不同浓度低聚异麦芽糖与葡萄糖时,长双歧杆菌与嗜酸乳杆菌的数量显著增加。体内实验中,实验组小鼠灌胃低聚异麦芽糖14 d后,与正常组相比,粪便中乳杆菌与双歧杆菌都极显著增加,B/E值也明显提高,且低剂量组中肠杆菌显著减少;灌胃前后自身相比,乳杆菌和双歧杆菌数量也显著增加。灌胃便秘小鼠低聚异麦芽糖后,其首粒排黑便时间明显缩短,排黑便总量明显增加,小肠推进率明显提高。体外培养条件下,低聚异麦芽糖可以增加长双歧杆菌和嗜酸乳杆菌的数量;低聚异麦芽糖具有改善小鼠胃肠道菌群及润肠通便的功效。     

槲皮素对肠道菌群的调节作用研究

为探究槲皮素对肠道菌群的调节作用,利用光电比浊法动态观察槲皮素在体外对肠道优势菌肠球菌、肠杆菌、乳杆菌和双歧杆菌增殖的影响;利用盐酸林可霉素灌胃构造小鼠肠道菌群失调动物模型,通过小鼠体内实验评价槲皮素调节肠道菌群失调的效果。体外实验结果表明,在一定浓度范围内(0.01、0.05、0.1μmol/mL)槲皮素对乳杆菌增殖有明显扶植作用,超过这一范围时(0.5、1μmol/mL)对乳杆菌增殖强烈抑制,各浓度槲皮素均对肠球菌的体外增殖表现为强烈的抑制作用,对肠杆菌和双歧杆菌无明显的抑制作用但也不表现出扶植作用;体内实验表明,200、400 mg/kg BW槲皮素可增加小鼠肠道双歧杆菌数量。槲皮素可调节肠道菌群。     

乳双歧杆菌V9对头孢曲松钠作用小鼠肠道菌群的变化

该研究主要探讨了乳双歧杆菌V9对头孢曲松钠作用的小鼠肠道菌群的变化。头孢曲松钠连续灌胃5 d建立小鼠肠道菌群失调的模型,然后随机分为4组,分别为模型组及低、中和高剂量组。低、中和高剂量组灌胃不同剂量乳双歧杆菌V9溶液,另设正常对照组,与模型组灌胃等体积生理盐水,连续灌胃23 d。灌胃结束后,采集小鼠的粪便进行活菌计数和16S rDNA测序,检测粪便中微生物组成及分布,测定血清中IL-1β、IL-6、TNF-α以及IL-2的含量,测定小肠及肝脏组织中SOD、MDA、GSH、GSH-Px的含量,HE染色观察小鼠小肠组织病理学变化。结果表明,灌胃乳双歧杆菌V9溶液后,中、高剂量组IL-1β、IL-6、TNF-α及IL-2的含量分别显著降低31.73、17.04、12.57及31.71 pg/mL;高剂量组小肠及肝脏组织中MDA含量显著降低（p<0.01）,中、高剂量组SOD、GSH及GSH-Px均极显著升高（p<0.01）。同时,乳双歧杆菌V9使得头孢曲松钠导致的小鼠肠道菌群失调得到明显改善,粪便活菌计数显示高剂量组肠杆菌数量显著降低0.34 lg cfu/g,乳杆菌及双歧杆菌数量显著增加,分别增加0.40 lg cfu/g和0.26 lg cfu/g。拟普雷沃菌属和魏斯氏菌丰度显著降低（p<0.01）。说明乳双歧杆菌V9对由头孢曲松钠引起的肠道菌群失衡具有一定的调节作用,并调节菌群多样性。     

豆渣膳食纤维及豆渣超微化制品对小鼠肠道菌群的影响

用豆渣膳食纤维及豆渣超微化制品灌胃BALB/c小鼠,研究其对小鼠肠道菌群的影响。正常对照组用生理盐水进行灌胃,实验组分别以低剂量(0.5g/(kg.d))、高剂量(2.5g/(kg.d))灌胃水溶性膳食纤维(SDF)、非水溶性膳食纤维(IDF)、超微粉碎豆渣(SPO)和螺杆挤压-超微粉碎豆渣(ESPO)。实验期间,每周同一时间取小鼠粪便,采用选择性培养基检测小鼠粪便中乳酸杆菌、双歧杆菌、肠杆菌和肠球菌的数量。结果表明:灌胃的各个阶段,各实验组在灌胃豆渣膳食纤维及豆渣制品后对小鼠的肠道菌群均有明显影响,其中高剂量IDF、低剂量SDF和低剂量的ESPO对小鼠肠道菌群调理作用明显,在增加乳酸杆菌和双歧杆菌的同时,一定程度上抑制了肠球菌和肠杆菌的增长。     

牛蒡寡糖的提取及对小鼠肠道菌群的调节作用

目的：研究牛蒡多糖的提取条件和对小鼠肠道菌群的调节作用。方法：采用单因素试验和正交试验优化牛蒡多糖提取工艺。15 只小鼠随机分为空白对照组和牛蒡多糖低、高剂量组,每组5 只,经口灌胃给药,灌胃容积为10ml/kg,1 次/d,连续14d。给药结束后,分别采集小鼠粪便,检查肠道肠杆菌,乳杆菌和双歧杆菌。结果：牛蒡多糖优化提取条件为：温度80℃,固液比1:10(m/V),时间60min,提取两次。与空白对照组相比,牛蒡多糖组乳杆菌与双歧杆菌数量均显著增加(P ＜ 0.05),肠杆菌数量变化不明显(P ＞ 0.05)。结论：牛蒡多糖能有效调节小鼠肠道菌群,增殖乳杆菌和双歧杆菌数量。     

魔芋低聚糖对小鼠肠道菌群的调节作用

该实验研究了魔芋低聚糖（KOGM）对小鼠肠道菌群的调节作用。以不同剂量魔芋低聚糖连续灌胃小鼠35 d,测定血清生化指标,无菌条件下取小鼠粪便培养肠道菌群。结果表明,与对照组比较,魔芋低聚糖高剂量组（2.00 g/kg体质量）小鼠粪便中双歧杆菌和乳杆菌数量（对数值分别为3.65、3.81）显著增加（P＜0.05）,肠杆菌和产气杆菌数量无显著性变化（P＞0.05）;结肠内容物中乙酸、丙酸以及丁酸的含量（6.51 mmol/100 g、1.69 mmol/100 g、3.83 mmol/100 g）显著增加（P＜0.05）。说明魔芋低聚糖对小鼠肠道菌群有较好调节作用。     

黑菊芋多糖的润肠通便和调节肠道菌群作用

该研究旨在探索黑菊芋多糖对便秘小鼠肠道功能及菌群多样性的影响。将KM小鼠随机分为空白组、模型组和黑菊芋多糖低（2.5 g/kg·bw）、中（5.0 g/kg·bw）、高（10.0 g/kg·bw）剂量组。连续14 d利用复方地芬诺酯诱导便秘小鼠模型,并从第8 d起开始多糖干预。计算小鼠6 h内排便粒数和肠墨汁推进率,采用Illumina MiSeq高通量测序技术对其肠道菌群16S rDNA基因进行分析。结果显示,与模型组相比,低、中、高剂量黑菊芋多糖能够增加小鼠黑便粒数（分别增加48.21%、98.21%和78.57%）和小肠墨汁推进率（分别增加67.34%、107.05%和87.08%）,其中以中剂量效果最佳。中剂量组干预后,微生物多样性、丰富度以及厚壁菌门/拟杆菌比例和变形菌门丰度显著增加（p<0.05）,并促进肠道有益菌乳酸菌属和栖粪杆菌属增殖（p<0.05）。因此,适量食用黑菊芋多糖有助于逆转便秘造成的肠道菌群紊乱,改善便秘症状。     

酪蛋白糖巨肽(CGMP)对小鼠肠道菌群消长规律的影响

目的:研究了不同剂量的CGMP对小鼠肠道菌群的影响。方法:选用60只BALB/c小鼠(25～30g),随机分成十组(对照组和4～10七个试验组),每组6只;对照1组(日食组)既不灌胃CGMP也不灌胃安慰剂,对照2组灌胃甜乳清粉溶液(0.2ml),对照3组灌胃生理盐水(0.2ml),试验4～10组灌胃等体积(0.2ml)不同浓度的CGMP溶液,灌胃期为15d。分别于灌胃前以及试验的第3、5、7、10、15d和停止灌胃后一周(第22d)用逼迫法采集小鼠新鲜粪便进行菌群测定,观察肠道内菌群的消长规律。结果表明:与对照组相比,随着灌胃时间的延长,各试验组均可促进小鼠肠道和粪便中的双歧杆菌和乳酸杆菌增殖(p<0.01),使致病菌数量明显减少(p<0.05),对肠杆菌、肠球菌数量的影响不明显。CGMP对小鼠肠道菌群的影响作用存在最适剂量(100μg/d),最适剂量组使肠杆菌、肠球菌、致病菌数量明显减少。说明CGMP具有有效地促进和调控小鼠肠道生理性细菌、构筑膜菌群的作用。     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.     

Analysis for organic residues from aids to polymerization used to make plastics intended for food contact

Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (¹     

Tests of potential functional barriers for laminated multilayer food packages. Part II: Medium molecular weight permeants

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.     

The Ministry of Environmental Protection Issued "Feasible Technology Guidelines for Pollution Prevention and Control in Wood Pulping Process of the Paper Industry (Trial)" and Two Other Guiding Technical Documents

On December 27t＂, 2013, the Ministry of Environmenta Protection announced that, in order to implement ＂The Environmental Protection Law of the People＇ s Republic of China＂, improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including ＂Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry （Trial）＂     

1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China

正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.