副干酪乳杆菌ET-22及其后生元组分对白念珠菌的抑制作用

为探究具有预防龋齿功效的副干酪乳杆菌ET-22(Lactobacillus paracasei ET-22)活菌及其后生元组分(热灭活菌和分泌物)对白念珠菌的抑制作用,评价副干酪乳杆菌ET-22活菌及其后生元组分的抗氧化能力及白念珠菌菌丝转化抑制率后,采用注射免疫抑制剂和涂抹白念珠菌的方法建立ICR小鼠的口腔念珠菌病模型。造模前后,分别以饮水的方式连续给予18 d剂量为10⁹ CFU/mL的ET-22活菌以及相对应的后生元组分,研究副干酪乳杆菌ET-22对小鼠舌部组织形态及炎症因子表达情况的影响。10⁹ CFU/mL的副干酪乳杆菌ET-22对白念珠菌出芽抑制率最高,为37.84%;后生元组分中热灭活菌及分泌物抑制率分别为17.50%、28.00%。动物模型中,ET-22活菌及其后生元组分干预后,均显著降低了小鼠血清中IFN-γ含量;分泌物组显著降低了小鼠舌部组织中IFN-γ和TNF-α含量,活菌组只显著降低了TNF-α含量,活菌组和热灭活菌组显著提高了小鼠舌部组织中CCL20趋化因子含量及舌苔菌群的丰富度和多样性。组织病理切片显示：ET-22...     

粘质沙雷氏菌PL-06磷脂酶A1在大肠杆菌中的分泌表达及其条件优化

克隆粘质沙雷氏菌PL-06磷脂酶A1基因pla A,与载体p ET-22b(+)连接构建重组质粒p ET-22b(+)-pla A,并将重组质粒导入受体菌E.coli BL21(DE3)中表达,构建得到重组菌AP22,IPTG诱导表达目的蛋白后将培养基蛋白进行SDS-PAGE分析显示:重组蛋白以可溶性蛋白的形式大量存在于发酵液中,分子质量约35 ku,与预期蛋白大小一致。以磷脂酶A1酶活为指标,在单因素实验的基础之上,通过正交实验得到摇瓶培养最佳条件为:氨苄青霉素终浓度30μg/m L,IPTG加量0.25 mmol/L,温度为34℃,OD600值为0.3,诱导时间4 h。在此条件下重组胞外磷脂酶A1酶活可高达8.6 U/m L,比优化前提高了43.3%。     

猴头菇益生菌发酵对小鼠酒精性胃溃疡的保护作用

该实验采用保加利亚乳杆菌、嗜热链球菌、醋酸菌3种菌种发酵猴头菇,通过比较发酵液的DPPH自由基清除率,确定猴头菇发酵的最优条件。用猴头菇益生菌发酵液对酒精性胃溃疡模型的小鼠进行灌胃,测定胃溃疡小鼠胃组织中超氧化物歧化酶(SOD)、丙二醛(MDA)、过氧化氢酶(CAT)和血清中炎症因子白介素-6(IL-6)、白介素-10(IL-10)、肿瘤坏死因子-α(TNF-α)含量。结果表明,最佳发酵条件为起始p H值6.5、菌种复配比(保加利亚乳杆菌:嗜热链球菌:醋酸菌)1:1:1、接种量8.8%、发酵温度37.5℃、发酵时间27 h,发酵液菌落数为8.72×10⁹ CFU/mL、发酵液的DPPH自由基清除率可达79.59%。与模型组相比,高剂量组小鼠胃组织的SOD和CAT水平分别升高了71.38%和99.89%、MDA含量降低了47.45%;小鼠血清中的炎症因子TNF-α和IL-6含量分别降低了32.66%和34.95%、IL-10含量升高了100.46%,表明猴头菇益生菌发酵液对小鼠的急性酒精性胃溃疡有保护作用。该研究为猴头菇的应用提供了理论支持,为猴头菇新产品的开拓和益...     

治疗口腔溃疡的食方

口腔溃疡是口腔黏膜疾病中常见的溃疡性损害疾病,它虽然是口腔小疾,但是反复犯病也会让人痛苦不堪。那么到底是什么原因引起口腔溃疡?我们又能够怎样预防呢?多因脾积热和缺乏维生素B引起中医认为,口腔溃疡多由心脾积热、阴虚火旺引起。而现代医学认为,复发性口腔溃疡首先与免疫有着密切关系。如过度疲劳、工作压力大等现象的频繁出现,都会造成机体免疫力下降,从而导致复发性口腔溃疡的频繁发作。此外,缺乏B族维生素也会导致口腔溃疡的发生。维生素B不仅能够调节人体的新陈代谢,维持皮肤和肌肉的健康,还能增进免疫系统和神经系统的功能,促进细胞生长和分裂。治疗不如预防     

海带岩藻聚糖对艰难梭菌肠炎预防活性作用

该研究选用头孢哌酮诱导的艰难梭菌肠炎模型,探究岩藻聚糖对抗生素相关的艰难梭菌结肠炎的预防活性。结果表明,预先服用头孢哌酮期间同时口服300 mg/kg 岩藻聚糖（重均分子量126.65 kDa）10 d,可有效缓解艰难梭菌侵染引起的腹泻和结肠黏膜损伤。盲肠的菌群结构分析发现,口服岩藻聚糖能够明显抑制盲肠中肠炎相关的艰难梭菌和肠球菌的相对丰度,提高活泼瘤胃球菌、布劳特氏菌属等有益菌的相对丰度,同时减少盲肠中艰难梭菌毒素A（Clostridium difficile toxin A,Tcd A）和艰难梭菌毒素B（Clostridium difficile toxin B,Tcd B）的产生,但是对肠道菌群的丰度和多样性的恢复作用很小。岩藻聚糖还能减少结肠中巨噬细胞和中性粒细胞的浸润,下调促炎因子肿瘤坏死因子-α（tumour necrosis factor alpha,TNF-α）、干扰素-γ（interferon gama,IFN-γ）、白介素-1β（interleukin 1 beta,IL-1β）和白介素-6（interleukin 6,IL-6）的基因表达,上调抗炎因子白介素-4（interleukin 4,IL-4）和白介素-10（interleukin 10,IL-10）的基因表达。综上,岩藻聚糖不能恢复肠道菌群的丰度和结构,其预防艰难梭菌肠炎活性与抑制艰难梭菌的侵染、产毒活性、抗炎活性以及肠黏膜保护活性有关。因此,岩藻聚糖可以用于预防头孢哌酮相关的艰难梭菌肠炎。     

副干酪乳杆菌L9对卵白蛋白诱发的小鼠过敏性气道炎的调节作用

过敏性气道炎(哮喘)是一种以炎症细胞浸润,气道高反应性为特征,Th2主导气道炎症性疾病,主要是敏感人群因吸入花粉、尘螨等外界抗原而引起过敏反应。目前常见的治疗方式是糖皮质激素类药物,其副作用大,患者存在类固醇药物抗性等缺点。研究表明特定益生菌菌株具有免疫调节功能,在缓解过敏性气道炎症状等方面有着巨大的潜力。本研究采用卵白蛋白致敏小鼠急性哮喘模型,通过灌胃4.0×109CFU/d和4.0×107CFU/d活菌以及热致死副干酪乳杆菌L9,研究L9对哮喘的改善作用。结果表明:灌胃L9可以显著降低过敏性气道炎小鼠的气道高反应性,降低支气管肺泡灌洗液中嗜酸性粒细胞比例(P0.05),减轻肺部中小型气道附近炎症细胞的浸润;L9通过降低小鼠血清中的总的IgE(P0.001)和IgG1(P0.05),上调血清中IgG2a(P0.05),纠正小鼠体内的系统性免疫失衡;L9降低支气管肺泡灌洗液中Th2细胞分泌的细胞因子IL-4、IL-5、IL-13的含量(P0.05),提高Th1细胞分泌的IFN-γ(P0.05)和Treg细胞相关的TGF-β(P0.05),纠正小鼠肺部的Th2/Th1免疫失衡。灌胃热致死L9同样可以显著改善哮喘,纠正系统性免疫失衡和Th2/Th1免疫失衡。结论:副干酪乳杆菌L9通过调节Th1/Th2免疫平衡减缓小时过敏性气道炎症状。     

蓝莓叶总黄酮的体外抗炎功效评价

目的：通过体外实验方法从分子水平对蓝莓叶总黄酮的抗炎功效进行评价。方法：建立人永生化表皮细胞HaCaT与蓝莓叶总黄酮的共培养体系,利用反转录实时荧光定量聚合酶链式反应检测在不同培养时间点（0、15、30、60、120 min）白细胞介素-6（interleukin-6,IL-6）、IL-8、干扰素诱导蛋白-10（interferon-inducibleprotein-10,IP-10）等炎症细胞因子相关基因表达情况,观察蓝莓叶总黄酮的添加对这些基因表达的影响,并探讨蓝莓叶总黄酮在分子水平上的抗炎机理。结果：蓝莓叶总黄酮的添加能够提高抗炎因子IL-6、CXCR-2基因的表达量（P＜0.05）,降低促炎因子IL-8、IP-10基因的表达量（P＜0.05）,对CXCR-1基因的表达呈复杂型调节。结论：蓝莓叶总黄酮通过对炎症相关因子表达量产生影响,从而减弱促炎症反应,增强抗炎症反应,最终发挥抗炎功效。     

酸笋中具有抗炎活性乳酸菌的筛选及鉴定

从柳州采集的3 份酸笋发酵液样品中分离筛选得到46 株疑似乳酸菌菌株,通过耐酸、耐胆盐、模拟胃肠道实验以及体外黏附HT-29细胞和NO实验进行益生特性和抗炎活性研究,筛选得到1 株具有优良抗炎活性菌株SS-31,经16S rRNA基因序列测序鉴定为发酵乳杆菌（Lactobacillus fermentum）。结果表明：菌株SS-31具有较强耐酸能力,0.1%牛胆盐处理3 h后活菌数为107 CFU/mL,存活率高达90.02%;模拟人工胃液消化2 h后存活率为80.28%,模拟人工肠液处理2 h后存活率为3.63%;SS-31在体外对HT-29细胞有较高黏附性,黏附率为4.47%,略低于对照菌鼠李糖乳杆菌（Lactobacillus rhamnosus）LGG（4.95%）;在体外脂多糖刺激RAW264.7细胞炎症中,与模型组相比,SS-31组显著下调炎性物质NO分泌量（P＜0.05）;此外,SS-31能显著下调炎症因子白细胞介素（interleukin,IL）1β、IL-6的含量（P＜0.05）。从酸笋发酵液中筛选得到1 株具有优良益生特性的发酵乳杆菌SS-31,初步证明了乳酸菌SS-31在治疗炎症中具有潜在应用和开发价值。     

一株清酒乳杆菌的分离、鉴定及培养基优化

从传统食品谷物发酵液中筛选出1株乳杆菌,通过生理生化试验与菌落和菌株形态观察以及16S rRNA测序鉴定为清酒乳杆菌。以MRS培养基为基础培养基,活菌数为指标,改变基础培养基组成的成分及添加量,在此基础上,通过响应面优化培养基组成。结果表明最优培养基组成为鱼蛋白胨14.50 g/L、酵母浸粉6.50 g/L、葡萄糖28.00 g/L、柠檬酸三铵1.50 g/L、磷酸二氢钾2.00 g/L、硫酸镁0.20 g/L、硫酸锰0.12 g/L、吐温-80 1.20 mL/L,此条件下,活菌数达到3.125×10⁹ CFU/mL,相比MRS发酵培养基活菌数(1.980×10⁸ CFU/mL)提高了1 478.28%。该优化培养基具有活菌数高和经济方便的特点,为清酒乳杆菌的工业化生产提供借鉴。     

葡萄籽超微粉对高血脂金黄地鼠血浆NO、ET-1和C反应蛋白的影响

探讨葡萄籽超微粉对高血脂诱发的动脉粥样硬化（AS）的预防作用及其机制。选用100只金黄地鼠,随机分成对照组、高血脂组、葡萄籽低剂量组、葡萄籽中剂量组和葡萄籽高剂量组。在试验的4w时间内,除对照组饲喂基础饲料外,其余各组均饲喂高脂饲料。第8w末,取金黄地鼠血浆进行NO、ET-1和C反应蛋白含量测定。结果表明,葡萄籽超微粉可提高高血脂金黄地鼠血浆NO水平、降低血浆ET-1的含量,降低c．反应蛋白含量。葡萄籽超微粉可改善血管内皮功能,对动脉粥样硬化的发生有一定的预防作用。     

口腔益生菌的研究现状

口腔是一个复杂而完整的微生态系统。生活方式、外源性致病菌等外源因子可扰乱口腔微生物组与其宿主之间的共生关系引发龋齿、牙周炎、牙龈炎、口臭等口腔疾病。益生菌是一类活的并对人类机体局部或全身性健康都具有有益作用的微生物。传统上,益生菌被广泛用于功能性食品、医药保健、饲料等各个领域,最常见的用途是治疗或预防胃肠道感染和疾病,改善肠道健康。近十年,各种研究表明益生菌可通过抑制致病菌生长,改善口腔微生物菌群,调节口腔免疫力等方式对各种口腔疾病产生积极的防治效果。作为一种新兴的机体健康维护概念,维护口腔健康的益生菌及其作用机制日益受到国内外学者的密切关注,综述了口腔益生菌在常见口腔疾病中的潜在作用机制,阐述了利用口腔益生菌在防治口腔疾病时所面临的重要问题,同时在口腔益生菌未来的发展趋势和开发方向等方面剖析如何更好地利用口腔益生菌驱动健康食品产业发展,以期为口腔益生菌的深入研究及其在食品工业中的开发应用提供相应参考。     

Dental plaque – associated infections and antibacterial oral hygiene products

Dental plaque accumulates on hard non-shedding surfaces such as teeth, dentures and orthodontic appliances. This accumulation is facilitated by the absence of adequate oral hygiene procedures.
The term 'plaque' describes a mass of microorganisms embedded in an organic matrix of host and microbial origin. In addition to the aesthetic desirability of 'clean teeth, healthy gums and fresh breath' associated with the absence of plaque, obvious consequences of the presence of plaque include tooth decay (dental caries), gingivitis and periodontal (gum) disease and denture associated problems.
Thus the prevention of plaque formation, the reduction of plaque accumulation and the effective removal of plaque are considerations of the cosmetic and health professions alike.
There are many oral hygiene products available to the general public – toothpastes, mouthwashes, denture cleaners, and, more recently, chewing gums and novel mouthwashes. Several of these products have antimicrobial components.
This paper reviews the microbiology of plaque and plaque associated problems, and surveys the type of products currently available for maintenance of good oral hygiene. Potential areas for future development are also explored.     

Toxicological evaluation of polyphenol extract from Acerola (Malpighia emarginata DC.) fruit

ABSTRACT:  Acerola ( Malpighia emarginata DC.) is known to be one of the best fruits rich in ascorbic acid and polyphenols. Acerola polyphenols (APs) were found to have radical scavenging activities and inhibitory effects on both α-glucosidase and advanced glycation endproducts (AGEs) production. While polyphenols from several foodstuffs have been shown to be safe, APs, which differ from those of other foodstuffs, have not been evaluated for their toxicological properties. Here, we report preliminary toxicological and safety evaluations of crude APs (C-AP), which were obtained by eluting an XAD7HP column-adsorbed fraction of APs with 70% ethanol containing malic acid. The total polyphenol content of C-AP was 57.7% with the main polyphenols being proanthocyanidin and cyanidin-3-α- O -rhamnoside. For toxicological evaluations, C-AP was administered orally to rats at doses of 2000 mg/kg body weight (acute) or 100, 300, and 1000 mg/kg body weight/d for 28 (subacute) and 90 (subchronic) d. In the acute oral toxicological test, no deaths or abnormalities at necropsy on day 14 were observed, confirming that the minimum fatal dose of C-AP is greater than 2000 mg/kg body weight. In both subacute and subchronic toxicological tests, no death was recorded and the body weights and food intakes of the rats did not differ significantly from the control groups. Besides, there were no abnormal clinical signs related to administration of C-AP in any of the experimental animals. These results provide an important reference for the safety of APs as a food supplement for human consumption.     

Effect of oral calcium bolus supplementation on early-lactation health and milk yield in commercial dairy herds

The objective of this study was to evaluate the effect of supplementation with oral Ca boluses after calving on early-lactation health and milk yield. Cows in their second lactation or greater (n = 927) from 2 large dairies in Wisconsin were enrolled during the summer of 2010. Both herds were fed supplemental anions during the prefresh period and less than 1% of fresh cows were treated for clinical milk fever. Cows were scored before calving for lameness and body condition, and then randomly assigned to either a control group or an oral Ca bolus-supplemented group. Control cows received no oral Ca boluses around calving. Cows in the oral Ca bolus group received 2 oral Ca boluses (Bovikalc, Boehringer Ingelheim, St. Joseph, MO), one bolus 0 to 2 h after calving and the second 8 to 35 h after calving. The oral Ca bolus administration schedule allowed fresh cows to be restrained in headlocks only once daily. Whole-blood samples were collected immediately before the second oral Ca bolus was given and were analyzed for ionized Ca (Ca²⁺) concentration. Early-lactation health events were recorded and summed for each cow. Only 6 cases (0.6% of calvings) of clinical milk fever occurred during the trial, and only 14% of cows tested were hypocalcemic (Ca²⁺ less than 1.0 mmol/L) at 8 to 35 h after calving. Mean Ca²⁺ concentrations were not different between the control and oral Ca bolus-supplemented groups. Blood samples from the cows given oral Ca boluses were collected an average of 20.6 h after administration of the first bolus. Subpopulations of cows with significant responses to oral Ca bolus supplementation were identified based on significant interactions between oral Ca bolus supplementation and covariates in mixed multiple regression models. Lame cows supplemented with oral Ca boluses averaged 0.34 fewer health events in the first 30 d in milk compared with lame cows that were not supplemented with oral Ca boluses. Cows with a higher previous lactation mature-equivalent milk production (greater than 105% of herd rank) and supplemented with oral Ca boluses produced 2.9 kg more milk at their first test after calving compared with cows with higher previous lactation milk yields that were not supplemented. Results of this study indicate that lame cows and higher producing cows responded favorably to supplementation with oral Ca boluses. Supplementing targeted subpopulations of cows with oral Ca boluses was beneficial even for dairies with a very low incidence of hypocalcemia.