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941.
以椰子水为原料,利用6株乳酸菌:发酵乳杆菌L20、面包乳杆菌32-2-2、短乳杆菌64-1、植物乳杆菌A33、嗜热链球菌IFFI6038和德氏乳杆菌保加利亚亚种CICC6045发酵椰子水制备饮料,分析测定发酵椰子水主要成分、抑菌活性和感官评价的变化。试验结果表明,发酵48 h时,面包乳杆菌32-2-2发酵椰子水饮料总酸含量最高,达10.85 g/L;植物乳杆菌A33发酵椰子水饮料pH值最低为3.1;德氏乳杆菌保加利亚亚种CICC6045发酵椰子水饮料还原糖含量最低为0.03 g/L;植物乳杆菌A33的抑菌谱最广;抑菌活性与pH值和乳酸含量呈显著相关性。植物乳杆菌、嗜热链球菌和德氏乳杆菌保加利亚亚种发酵椰子水感官评分较高。 相似文献
942.
943.
In the last decade, a variety of ribosomally synthesized antimicrobial peptides, or bacteriocins, produced by lactic acid bacteria have been identified and characterized. As a result of these studies, insight has been gained into various fundamental aspects of biology and biochemistry such as bacteriocin processing and secretion, mechanisms of cell immunity, and structure-function relationships. In parallel, there has been a growing awareness that bacteriocins may be developed into useful antimicrobial food additives. Class IIa bacteriocins can be considered as the major subgroup of bacteriocins from lactic acid bacteria, not only because of their large number, but also because of their significant biological activities and potential applications. The present review provides an overview of the knowledge available for class IIa bacteriocins and discusses common features and recent findings concerning these substances. The activity and potential food applications of class IIa bacteriocins are a major focus of this review. 相似文献
944.
Vantha Choub Henry B. Ajuna Sang-Jae Won Jae-Hyun Moon Su-In Choi Chaw Ei Htwe Maung Chul-Woo Kim Young Sang Ahn 《International journal of molecular sciences》2021,22(19)
Walnut anthracnose caused by Colletotrichum gloeosporioides is a deleterious disease that severely affects the production of walnut (Juglans regia L.). The aim of this study was to assess the antifungal and growth promotion activities of Bacillus velezensis CE 100 as an alternative to chemical use in walnut production. The crude enzyme from B. velezensis CE 100 exhibited chitinase, protease, and β-l,3-glucanase activity and degraded the cell wall of C. gloeosporioides, causing the inhibition of spore germination and mycelial growth by 99.3% and 33.6% at 100 µL/mL, respectively. The field application of B. velezensis CE 100 culture broth resulted in a 1.3-fold and 6.9-fold decrease in anthracnose disease severity compared to the conventional and control groups, respectively. Moreover, B. velezensis CE 100 produced indole-3-acetic acid (up to 1.4 µg/mL) and exhibited the potential for ammonium production and phosphate solubilization to enhance the availability of essential nutrients. Thus, field inoculation of B. velezensis CE 100 improved walnut root development, increased nutrient uptake, enhanced chlorophyll content, and consequently improved total biomass by 1.5-fold and 2.0-fold compared to the conventional and control groups, respectively. These results demonstrate that B. velezensis CE 100 is an effective biocontrol agent against anthracnose disease and a potential plant growth-promoting bacteria in walnut tree production. 相似文献
945.
陶瓷釉面砖上制备TiO2杀菌薄膜 总被引:2,自引:0,他引:2
采用溶胶-凝胶法,以钛酸四丁酯为先驱体,无水乙醇为溶剂,乙酰丙酮为稳定剂,Ag^+为辅助杀菌剂,在陶质釉面砖上制备出TiO2薄膜,经生物检测,其8h杀菌率在90%以上。 相似文献
946.
李娟 《土木与环境工程学报》1999,21(6):60-65
针对影响住宅室内空气品质的空气中细菌浓度水平进行测试、分析、研究。通过对住宅室内空气中的微生物浓度进行测定, 并对造成室内空气中细菌污染的原因进行分析,指出在重庆住宅室内空气中存在着严重的细菌污染问题,其主要影响因素是空气的湿度和自然通风、采光情况;建筑结构形式、室内布置和地面装饰材料也是较重要的影响因素。提出提高室内空气品质,改善室内环境质量,防止室内空气中细菌污染的措施、建议 相似文献
947.
948.
Evangelia A. Tsapou Fotini Drosou Elisabeth Koussissi Maria Dimopoulou Thalia Dourtoglou Vassilis Dourtoglou 《Journal of food science》2020,85(7):2069-2079
Triggered by the development of lactic acid bacteria (LAB) during the production of Scotch whisky, this study examined the influence of yeast and LAB inoculation on whisky flavor. Four new spirits were produced using the same process. LAB were added as a form of a Greek yogurt's live culture. In each category (barley and rye), one sample was fermented with Greek yogurt while the other was fermented without it. The spirits were matured and analyzed at five different points. Results from gas chromatography-mass spectrometry (GC-MS) analysis showed basic volatile compounds, along with some important extra compounds with yogurt culture. The most obvious differences were observed in the concentration of butanoic acid, a characteristic acid in spirits undergoing lactic acid fermentation: to identify esters such as ethyl butanoate, ethyl isobutanoate, isoamyl butanoate, and 2-phenylethyl butanoate, they are not typical compounds in whisky. 相似文献
949.
950.
乳酸菌胞外多糖发酵条件优化及抗肿瘤活性的研究 总被引:1,自引:0,他引:1
该研究以胞外多糖产量为评价指标,采用单因素试验及响应面试验对副干酪乳杆菌副干酪亚种(Lactobacillus paracasei subsp. paracasei)M5L产胞外多糖的发酵条件进行优化,并采用噻唑蓝(MTT)法及实时荧光定量聚合酶链式反应(RT-FQPCR)研究胞外多糖的抗肿瘤活性。结果表明,乳酸菌M5L产胞外多糖的最优发酵条件为发酵温度37 ℃、发酵时间12.8 h、初始pH值7.7、菌体浓度108 CFU/mL,在此最优发酵条件下,胞外多糖产量达到最大,为167.2 mg/mL,是优化前的1.3倍。当质量浓度为500 μg/mL的胞外多糖对Caco-2细胞处理72 h时,抑制作用最佳,抑制率达19.5%,显著增加胞内Caspase-3、Bax基因且降低Bcl-2基因的表达量,说明该胞外多糖可通过影响凋亡相关蛋白的表达来促进Caco-2细胞凋亡。 相似文献