以采自辽宁省不同地区农家38份传统发酵豆酱样品为试材,通过选择性培养分离出豆酱中的优势乳酸菌及酵母菌疑似菌株,再利用16S r DNA和26S r DNA D1/D2序列分析方法,对其进行初步鉴定并保藏。结果表明,14个地区38份样品中共分离到乳酸菌6...以采自辽宁省不同地区农家38份传统发酵豆酱样品为试材,通过选择性培养分离出豆酱中的优势乳酸菌及酵母菌疑似菌株,再利用16S r DNA和26S r DNA D1/D2序列分析方法,对其进行初步鉴定并保藏。结果表明,14个地区38份样品中共分离到乳酸菌62株,初步鉴定结果为L.plantarum 19株、E.faecium 14株、T.halophilus1 2株、L.s a k e i 1 1株、L.fermentum 4株、P.p e n t o s a c e u s 2株。分离到酵母菌5 6株,初步鉴定结果为Zygosaccharomyces 18株、Candida 13株、C.parapsilosis 14株、D.hansenii 7株、Debaryomyces 4株。丹东市、沈阳市、阜新市等地区的样品中乳酸菌和酵母菌的多样性较好。展开更多
本实验以从云南省采集的4个品种的芒果果皮作为分离源,经分离、纯化及三级筛选得到6株在芒果汁基质中具有良好发酵力的酵母菌。利用WL营养培养基对所筛得酵母菌进行初步分类,结合26S r DNA测序鉴定,除1株为Hanseniaspora opuntiae,另外...本实验以从云南省采集的4个品种的芒果果皮作为分离源,经分离、纯化及三级筛选得到6株在芒果汁基质中具有良好发酵力的酵母菌。利用WL营养培养基对所筛得酵母菌进行初步分类,结合26S r DNA测序鉴定,除1株为Hanseniaspora opuntiae,另外5株均为Wickerhamomyces anomalus。其中DTM9(W.anomalu)和DKT11(H.opuntiae)发酵芒果酒的气相色谱-质谱联用(gas chromatography-mass spectrometry,GC-MS)分析结果表明,与芒果清汁相比,DTM9发酵的芒果酒中,酯类物质含量增加了51.63%,种类增加了400%;醇类物质含量增加28.37%,种类增加了27.27%;DKT11发酵的芒果酒中酯类物质含量增加了44.27%,种类增加了433%;醇类物质含量增加了34.17%。综合比较理化指标和感官分析结果,DTM9具有更高的糖利用率,且发酵的芒果酒感官品质更优良,对提高芒果酒的香气质量有重要意义。展开更多
△^12 fatty acid desaturase gene has been targeted as a logical candidate controlling the high oleate trait in peanut seeds. By RT-PCR method, the full-length cDNAs of △^12 fatty acid desaturase gene were isolated fr...△^12 fatty acid desaturase gene has been targeted as a logical candidate controlling the high oleate trait in peanut seeds. By RT-PCR method, the full-length cDNAs of △^12 fatty acid desaturase gene were isolated from peanut （Arachis hypogaea L.） genotypes with normal and high ratio of oleic to linoleic acid, which were designated AhFAD2B and AhFAD2B＇, respectively. Sequence alignment of their coding regions revealed that an extra A was inserted at the position ＋442 bp of AhFAD2B＇ sequence of high oleic acid genotypes, which resulted in the shift of open reading frame and a truncated protein AhFAD2B＇, with the loss of one histidine box involved in metal ion complex required for the reduction of oxygen. Analysis of transcript level showed that the expression of △^12 fatty acid desaturase gene in high oleic acid genotype was slightly lower than that in normal genotype. The enzyme activity experiment of yeast （Saccharomyces cerevisiae） cell transformed with AhFAD2B or AhFAD2B＇ proved that only AhFAD2B gene product showed significant △^12 fatty acid desaturase activity, but AhFAD2B＇ gene product did not. These results suggested that the change of AhFAD2B＇ gene sequence resulted in lower activity or deactivation of △^12 fatty acid desaturase in high oleic acid genotype.展开更多
以甘肃河西走廊葡萄酒产区成熟葡萄浆果自然发酵过程中分离得到的115株酵母菌株为出发菌株,采用对硝基苯基-β-D-吡喃葡萄糖苷为底物的平板初筛,摇瓶复筛,对高产β-葡萄糖苷酶酵母菌株进行WL营养培养基和赖氨酸培养基初步分类以及26S r ...以甘肃河西走廊葡萄酒产区成熟葡萄浆果自然发酵过程中分离得到的115株酵母菌株为出发菌株,采用对硝基苯基-β-D-吡喃葡萄糖苷为底物的平板初筛,摇瓶复筛,对高产β-葡萄糖苷酶酵母菌株进行WL营养培养基和赖氨酸培养基初步分类以及26S r DNA D1/D2区序列分析。结果表明:6株酵母β-葡萄糖苷酶活性与商业酵母ICV-D254酶活性相似,酶活力可达(51.40±4.74)m U/m L,其中菌株QLFE、MQFEH-1、MQFSC-3、MQFEH-2和MQFSM-3为酿酒酵母属,菌株QLFE-4为梅奇酵母属,与分子鉴定结果一致。展开更多
文摘以采自辽宁省不同地区农家38份传统发酵豆酱样品为试材,通过选择性培养分离出豆酱中的优势乳酸菌及酵母菌疑似菌株,再利用16S r DNA和26S r DNA D1/D2序列分析方法,对其进行初步鉴定并保藏。结果表明,14个地区38份样品中共分离到乳酸菌62株,初步鉴定结果为L.plantarum 19株、E.faecium 14株、T.halophilus1 2株、L.s a k e i 1 1株、L.fermentum 4株、P.p e n t o s a c e u s 2株。分离到酵母菌5 6株,初步鉴定结果为Zygosaccharomyces 18株、Candida 13株、C.parapsilosis 14株、D.hansenii 7株、Debaryomyces 4株。丹东市、沈阳市、阜新市等地区的样品中乳酸菌和酵母菌的多样性较好。
文摘△^12 fatty acid desaturase gene has been targeted as a logical candidate controlling the high oleate trait in peanut seeds. By RT-PCR method, the full-length cDNAs of △^12 fatty acid desaturase gene were isolated from peanut （Arachis hypogaea L.） genotypes with normal and high ratio of oleic to linoleic acid, which were designated AhFAD2B and AhFAD2B＇, respectively. Sequence alignment of their coding regions revealed that an extra A was inserted at the position ＋442 bp of AhFAD2B＇ sequence of high oleic acid genotypes, which resulted in the shift of open reading frame and a truncated protein AhFAD2B＇, with the loss of one histidine box involved in metal ion complex required for the reduction of oxygen. Analysis of transcript level showed that the expression of △^12 fatty acid desaturase gene in high oleic acid genotype was slightly lower than that in normal genotype. The enzyme activity experiment of yeast （Saccharomyces cerevisiae） cell transformed with AhFAD2B or AhFAD2B＇ proved that only AhFAD2B gene product showed significant △^12 fatty acid desaturase activity, but AhFAD2B＇ gene product did not. These results suggested that the change of AhFAD2B＇ gene sequence resulted in lower activity or deactivation of △^12 fatty acid desaturase in high oleic acid genotype.
文摘以甘肃河西走廊葡萄酒产区成熟葡萄浆果自然发酵过程中分离得到的115株酵母菌株为出发菌株,采用对硝基苯基-β-D-吡喃葡萄糖苷为底物的平板初筛,摇瓶复筛,对高产β-葡萄糖苷酶酵母菌株进行WL营养培养基和赖氨酸培养基初步分类以及26S r DNA D1/D2区序列分析。结果表明:6株酵母β-葡萄糖苷酶活性与商业酵母ICV-D254酶活性相似,酶活力可达(51.40±4.74)m U/m L,其中菌株QLFE、MQFEH-1、MQFSC-3、MQFEH-2和MQFSM-3为酿酒酵母属,菌株QLFE-4为梅奇酵母属,与分子鉴定结果一致。
