为了提高酵素粉中益生菌的存活率以及产品的活性,该研究以植物乳杆菌Lactobacillus plantarum 1-33(Lp 1-33)为发酵菌株,高密度培养后对发酵上清液进行喷雾干燥;通过内源乳化法对菌体进行微胶囊包埋,再对微胶囊进行真空冷冻干燥,最后2...为了提高酵素粉中益生菌的存活率以及产品的活性,该研究以植物乳杆菌Lactobacillus plantarum 1-33(Lp 1-33)为发酵菌株,高密度培养后对发酵上清液进行喷雾干燥;通过内源乳化法对菌体进行微胶囊包埋,再对微胶囊进行真空冷冻干燥,最后2部分产物经混匀造粒制得益生菌酵素粉;以包埋率、胃肠道存活率、释放率等为指标,考察多重保护技术对其活性的保护效果。结果表明:采用内源乳化法,乙二胺四乙酸钙为钙载体,质量分数1.5%海藻酸钠为壁材,质量分数0.3%壳聚糖-三聚磷酸钠为涂层材料效果最佳;此条件下制备的微胶囊包埋率≥80%,经模拟胃液处理2 h后其菌体存活率≥50%,模拟肠液处理2 h后释放率≥90%;最佳冷冻保护剂配方为质量分数10%脱脂奶粉、质量分数8%乳糖、质量分数1%抗坏血酸钠、质量分数1%谷氨酸钠,酵素粉与保护剂比例1:10;制备的酵素粉30℃保存3个月,活菌数仍≥9.5lg(CFU/g);与发酵前果汁相比,其清除自由基能力提高了近20%。通过上述多重活性保护技术,提高了菌体的存活率和抗逆境能力,获得高密度、高活性的益生菌酵素粉,为后续产业化的生产提供技术支撑。展开更多
以西番莲果皮益生菌发酵浆为材料,结合真空冷冻干燥工艺,研究了冻干保护剂对酵素粉理化特性、菌体活力的影响,并对模拟消化条件下酵素粉中益生菌的活力进行了评价。结果表明,①冻干保护剂组合,脱脂乳粉+海藻糖添加量5+5(g/100 mL),制备...以西番莲果皮益生菌发酵浆为材料,结合真空冷冻干燥工艺,研究了冻干保护剂对酵素粉理化特性、菌体活力的影响,并对模拟消化条件下酵素粉中益生菌的活力进行了评价。结果表明,①冻干保护剂组合,脱脂乳粉+海藻糖添加量5+5(g/100 mL),制备得到的酵素粉均匀细腻,无颗粒感,流动性明显改善,益生菌存活率较直接冻干的空白对照组提高34.9%。②模拟消化条件下,酵素粉经模拟胃液消化3 h后,活菌数7.00 lg CFU/g,存活率为77%;在肠液中3h后,活菌数为8.00 lg CFU/g,存活率达到88%;在低浓度胆酸盐的模拟胆汁中3 h后的活菌数较高,为6.00 lg CFU/g,而在高浓度胆酸盐的模拟胆汁中3 h后益生菌活菌为5.78 lg CFU/g;在模拟胃液,肠液及胆汁酸中,制备的酵素粉中益生菌均表现出良好的生存特性,活菌数可以维持在6.00 lg CFU/g以上,确保酵素粉摄入后能发挥益生菌作用。展开更多
A mutant (GQQ-M6) of a Sponge-Derived streptomyces sp. GQQ-10 obtained by UV-induced mutation was used for producing prodiginines (PGs). Single factor experiments and orthogonal array design (OAD) methods were employe...A mutant (GQQ-M6) of a Sponge-Derived streptomyces sp. GQQ-10 obtained by UV-induced mutation was used for producing prodiginines (PGs). Single factor experiments and orthogonal array design (OAD) methods were employed for medium optimization. In the single factor method, the effects of soluble starch, glucose, soybean flour, yeast extract and sodium acetate on PGs production were investigated individually. In the subsequent OAD experiments, the concentrations of these 5 key nutritional components combined with salinity were further adjusted. The mutant strain GQQ-M6 gave a 2.2-fold higher PGs production than that of the parent strain; OAD experiments offered a PGs yield of 61mg L-1, which was 10 times higher than that of the initial GQQ-10 strain under the original cultivation mode.展开更多
In this study, the rice straw was hydrolysed by using 3.0% （w/v） H2SO4 followed by enzymatic hydrolysis. The rice straw hydrolysate obtained was treated with charcoal powder and the optimal condition of detoxificati...In this study, the rice straw was hydrolysed by using 3.0% （w/v） H2SO4 followed by enzymatic hydrolysis. The rice straw hydrolysate obtained was treated with charcoal powder and the optimal condition of detoxification with charcoal powder was investigated. The results showed that the optimal condition for detoxification was the use of 2.5 grams of non-sterilized charcoal powder in 100 mL hydrolysate. The mixture was operated at pH 5.0, 30 ℃ and 160 rpm for 5 min. The detoxified hydrolysate was then used for ethanol production using P. stipitis TISTR 5806. The condition of the detoxified hydrolysate fermentation which gave maximum ethanol concentration of 21 g/L was at pH 5.0, 30 ℃ and 160 rpm for 72 h. Without detoxification, the P. stipitis TISTR 5806 could not however utilize the hydrolysate for ethanol production.展开更多
文摘以西番莲果皮益生菌发酵浆为材料,结合真空冷冻干燥工艺,研究了冻干保护剂对酵素粉理化特性、菌体活力的影响,并对模拟消化条件下酵素粉中益生菌的活力进行了评价。结果表明,①冻干保护剂组合,脱脂乳粉+海藻糖添加量5+5(g/100 mL),制备得到的酵素粉均匀细腻,无颗粒感,流动性明显改善,益生菌存活率较直接冻干的空白对照组提高34.9%。②模拟消化条件下,酵素粉经模拟胃液消化3 h后,活菌数7.00 lg CFU/g,存活率为77%;在肠液中3h后,活菌数为8.00 lg CFU/g,存活率达到88%;在低浓度胆酸盐的模拟胆汁中3 h后的活菌数较高,为6.00 lg CFU/g,而在高浓度胆酸盐的模拟胆汁中3 h后益生菌活菌为5.78 lg CFU/g;在模拟胃液,肠液及胆汁酸中,制备的酵素粉中益生菌均表现出良好的生存特性,活菌数可以维持在6.00 lg CFU/g以上,确保酵素粉摄入后能发挥益生菌作用。
基金supported by the National Natural Science Foundation of China (Nos.30973627 and 30772640)the public projects of the State Oceanic Administration (No.2010418022-3)+1 种基金the Program for Changjiang Scholars and Innovative Research Team in University (No.IRT0944)the Natural Science Fund of Shandong Province,P.R.China (No.ZR2009CZ016)
文摘A mutant (GQQ-M6) of a Sponge-Derived streptomyces sp. GQQ-10 obtained by UV-induced mutation was used for producing prodiginines (PGs). Single factor experiments and orthogonal array design (OAD) methods were employed for medium optimization. In the single factor method, the effects of soluble starch, glucose, soybean flour, yeast extract and sodium acetate on PGs production were investigated individually. In the subsequent OAD experiments, the concentrations of these 5 key nutritional components combined with salinity were further adjusted. The mutant strain GQQ-M6 gave a 2.2-fold higher PGs production than that of the parent strain; OAD experiments offered a PGs yield of 61mg L-1, which was 10 times higher than that of the initial GQQ-10 strain under the original cultivation mode.
文摘In this study, the rice straw was hydrolysed by using 3.0% （w/v） H2SO4 followed by enzymatic hydrolysis. The rice straw hydrolysate obtained was treated with charcoal powder and the optimal condition of detoxification with charcoal powder was investigated. The results showed that the optimal condition for detoxification was the use of 2.5 grams of non-sterilized charcoal powder in 100 mL hydrolysate. The mixture was operated at pH 5.0, 30 ℃ and 160 rpm for 5 min. The detoxified hydrolysate was then used for ethanol production using P. stipitis TISTR 5806. The condition of the detoxified hydrolysate fermentation which gave maximum ethanol concentration of 21 g/L was at pH 5.0, 30 ℃ and 160 rpm for 72 h. Without detoxification, the P. stipitis TISTR 5806 could not however utilize the hydrolysate for ethanol production.
