许多研究表明人参皂苷是人参中起主要药效活性的物质,尤其是人参稀有皂苷比人参主皂苷在抗癌、抗心脑血管病、抗糖尿病等方面具有更好的疗效。利用从17年生野山参中分离、筛选获得一株人参内生真菌Burkholderia sp. GE 17-7生物转化人...许多研究表明人参皂苷是人参中起主要药效活性的物质,尤其是人参稀有皂苷比人参主皂苷在抗癌、抗心脑血管病、抗糖尿病等方面具有更好的疗效。利用从17年生野山参中分离、筛选获得一株人参内生真菌Burkholderia sp. GE 17-7生物转化人参主皂苷。通过薄层色谱法、高效液相色谱法等方法对人参主皂苷(Rb1、Rb2、Rc、Rd、Re和Rg1)的转化产物进行分离纯化,采用波谱解析及理化常数对其进行结构鉴定。同时,对转化路径进行了分析。结果表明人参内生真菌Burkholderia sp. GE 17-7能够特异性水解原人参二醇型皂苷C-20位糖基,对其内部糖基不具有水解特性。经鉴定其转化产物为人参稀有皂苷Rg3。转化路径为人参皂苷Rb1→人参皂苷Rd→人参稀有皂苷Rg3。人参内生真菌Burkholderia sp. GE 17-7能够特异性制备人参稀有皂苷Rg3,为工业制备人参稀有皂苷提供了新的微生物资源。展开更多
Lignocellulose—a major component of biomass available on earth is a renewable and abundantly available with great potential for bioconversion to value-added bio-products. The review aims at physio-chemical features o...Lignocellulose—a major component of biomass available on earth is a renewable and abundantly available with great potential for bioconversion to value-added bio-products. The review aims at physio-chemical features of lignocellulosic biomass and composition of different lignocellulosic materials. This work is an overview about the conversion of lignocellulosic biomass into bio-energy products such as bio-ethanol, 1-butanol, bio-methane, bio-hydrogen, organic acids including citric acid, succinic acid and lactic acid, microbial polysaccharides, single cell protein and xylitol. The biotechnological aspect of bio-transformation of lignocelluloses research and its future prospects are also discussed.展开更多
The DL-lysine crystals from the racemization of L-lysine was treated as substrate with Hafnia alvei AS1.1009 intact cells as biocatalysts to produce crystal-line D-lysine with a yield of 56.6%from the reaction mixture...The DL-lysine crystals from the racemization of L-lysine was treated as substrate with Hafnia alvei AS1.1009 intact cells as biocatalysts to produce crystal-line D-lysine with a yield of 56.6%from the reaction mixture after simple purification.In the presence of 0.10 molar equivalent of salicylaldehyde,L-lysine race-mization can be completed within 4 h in 1.0 mol/L of NaOH at 100℃.The activation energy of the processes was 62187.86 J/mol.The characteristics of Hafnia alvei AS1.1009 decarboxylase were studied.Under the condi-tions of pH 8.0,temperature 37uC,cell concentration 10 g/L,tween-800.5 g/L,substrate concentration 30 g/L,and the specific activity of up to 3840 U,L-lysine can be completely degraded by the decarboxylase for 12 h under the optimal conditions.展开更多
文摘许多研究表明人参皂苷是人参中起主要药效活性的物质,尤其是人参稀有皂苷比人参主皂苷在抗癌、抗心脑血管病、抗糖尿病等方面具有更好的疗效。利用从17年生野山参中分离、筛选获得一株人参内生真菌Burkholderia sp. GE 17-7生物转化人参主皂苷。通过薄层色谱法、高效液相色谱法等方法对人参主皂苷(Rb1、Rb2、Rc、Rd、Re和Rg1)的转化产物进行分离纯化,采用波谱解析及理化常数对其进行结构鉴定。同时,对转化路径进行了分析。结果表明人参内生真菌Burkholderia sp. GE 17-7能够特异性水解原人参二醇型皂苷C-20位糖基,对其内部糖基不具有水解特性。经鉴定其转化产物为人参稀有皂苷Rg3。转化路径为人参皂苷Rb1→人参皂苷Rd→人参稀有皂苷Rg3。人参内生真菌Burkholderia sp. GE 17-7能够特异性制备人参稀有皂苷Rg3,为工业制备人参稀有皂苷提供了新的微生物资源。
文摘Lignocellulose—a major component of biomass available on earth is a renewable and abundantly available with great potential for bioconversion to value-added bio-products. The review aims at physio-chemical features of lignocellulosic biomass and composition of different lignocellulosic materials. This work is an overview about the conversion of lignocellulosic biomass into bio-energy products such as bio-ethanol, 1-butanol, bio-methane, bio-hydrogen, organic acids including citric acid, succinic acid and lactic acid, microbial polysaccharides, single cell protein and xylitol. The biotechnological aspect of bio-transformation of lignocelluloses research and its future prospects are also discussed.
基金This work was supported by the Innovation Foundation of China(No.02CJ-13-01-16)the Dean Foundation of Xuzhou Medical College(No.07KJZ07).
文摘The DL-lysine crystals from the racemization of L-lysine was treated as substrate with Hafnia alvei AS1.1009 intact cells as biocatalysts to produce crystal-line D-lysine with a yield of 56.6%from the reaction mixture after simple purification.In the presence of 0.10 molar equivalent of salicylaldehyde,L-lysine race-mization can be completed within 4 h in 1.0 mol/L of NaOH at 100℃.The activation energy of the processes was 62187.86 J/mol.The characteristics of Hafnia alvei AS1.1009 decarboxylase were studied.Under the condi-tions of pH 8.0,temperature 37uC,cell concentration 10 g/L,tween-800.5 g/L,substrate concentration 30 g/L,and the specific activity of up to 3840 U,L-lysine can be completely degraded by the decarboxylase for 12 h under the optimal conditions.
