RESUMO
In this study, we developed a novel liquid fermentation medium of Cordyceps militaris using pupa powder and wheat bran as nitrogen resources instead of the traditionally used peptone. This process not only reduced the cost by approximately 50%, but increased production by over 30%. Then, we explored a method to extract and purify cordycepin by combining hydrothermal reflux extraction with macroporous resin adsorption, which is inexpensive and suitable for the industrial production. The optimum conditions for hydrothermal reflux were extracting three times at 95 °C with 1:10 sample-to-water ratio, and the cordycepin purity with macroporous resin HPD-100 reached 95.23%.[Formula: see text].
Assuntos
Cordyceps , Desoxiadenosinas , Fermentação , Estrutura MolecularRESUMO
In this paper, the catalytic performance of non-purified esterase from wheat bran immobilized on glass fibre membrane carrier is established, the immobilization conditions observed were enzyme 1â¯mL, phosphate buffer 3â¯mL (pHâ¯7.0), immobilization time 1â¯h, immobilization temperature 29⯰C. After carrier functionalization some characteristics of immobilized enzyme were studied, the results showed that immobilized enzyme presenting improved characteristic than that of free enzyme. The optimum pH for free and immobilized enzymes were found to be 8 and 7, respectively. As for optimum temperature for free and immobilized enzymes were observed to be 30⯰C and 40⯰C, respectively. When the enzyme was immobilized on glass fibre membranes, its Km increased about 7 times. In addition, storage and thermal stability of the free wheat esterase were increased by as a result of membrane immobilization, after 12â¯days of storage, the immobilized enzyme still retained about 91.10% of its original activity at 4⯰C, indicating a great potential in industrial application.
Assuntos
Enzimas Imobilizadas , Esterases/química , Vidro , Triticum/química , Ativação Enzimática , Estabilidade Enzimática , Enzimas Imobilizadas/química , Esterases/isolamento & purificação , Esterases/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Extração Líquido-Líquido , TemperaturaRESUMO
Recently, we have found that the accumulation of ripening inhibitor (RIN) protein increased gradually during tomato fruit ripening. Here, the recombinant protein was expressed in Escherichia coli and affinity-purified. The DNA binding activity of renatured RIN protein was tested by electrophoretic mobility shift assay. The results indicated that an optimal expression and purification system was suitable for obtaining active RIN with DNA binding activity.
Assuntos
DNA de Plantas/genética , DNA de Plantas/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Solanum lycopersicum/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/isolamento & purificação , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/isolamento & purificação , Proteínas de Domínio MADS/metabolismo , Fases de Leitura Aberta , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Proteínas Recombinantes/metabolismo , Proteínas Repressoras/isolamento & purificação , Fatores de Transcrição/isolamento & purificaçãoRESUMO
The tomato ripening mutant, ripening inhibitor (rin), whose fruits fails to ripen, has been identified and widely studied. The RIN gene has been cloned. Here we present the expression of a truncated form of the RIN protein from tomato and the preparation of a polyclonal antibody against it. The resulting antibody recognized the RIN of crude protein extracts from different tomato tissues. The protein level of RIN in tomato was detected with this antibody by western blot, which suggested the accumulation of RIN protein increased gradually during tomato fruit ripening.