RESUMO
Abstract Chaetoglobosin A is an antibacterial compound produced by Chaetomium globosum, with potential application as a biopesticide and cancer treatment drug. The aim of this study was to evaluate the feasibility of utilizing cornstalks to produce chaetoglobosin A by C. globosum W7 in solid-batch fermentation and to determine an optimal method for purification of the products. The output of chaetoglobosin A from the cornstalks was 0.34 mg/g, and its content in the crude extract was 4.80%. Purification conditions were optimized to increase the content of chaetoglobosin A in the crude extract, including the extract solvent, temperature, and pH value. The optimum process conditions were found to be acetone as the extractant, under room temperature, and at a pH value of 13. Under these conditions, a production process of the antifungal chaetoglobosin A was established, and the content reached 19.17%. Through further verification, cornstalks could replace crops for the production of chaetoglobosin A using this new production process. Moreover, the purified products showed great inhibition against Rhizoctonia solani, with chaetoglobosin A confirmed as the main effective constituent (IC50 = 3.88 µg/mL). Collectively, these results demonstrate the feasibility of using cornstalks to synthesize chaetoglobosin A and that the production process established in this study was effective.
Assuntos
Microbiologia Industrial/métodos , Calosidades/microbiologia , Chaetomium/metabolismo , Alcaloides Indólicos/metabolismo , Antifúngicos/metabolismo , Resíduos/análise , Microbiologia Industrial/instrumentação , Calosidades/metabolismo , Estrutura Molecular , Caules de Planta/metabolismo , Caules de Planta/microbiologia , Alcaloides Indólicos/isolamento & purificação , Alcaloides Indólicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/químicaRESUMO
Abstract Very high gravity (VHG) technology was employed on industrial scale to produce ethanol from molasses (fermented) as well as by-products formation estimation. The effect of different Brix° (32, 36 and 40) air-flow rates (0.00, 0.20, 0.40, and 0.60 vvm) was studied on ethanol production. The maximum ethanol production was recorded to be 12.2% (v/v) at 40 Brix° with 0.2 vvm air-flow rate. At optimum level aeration and 40 Brix° VHG, the residual sugar level was recorded in the range of 12.5-18.5 g/L, whereas the viable cell count remained constant up to 50 h of fermentation and dry matter production increased with fermentation time. Both water and steam consumption reduced significantly under optimum conditions of Brix° and aeration rate with compromising the ethanol production. Results revealed VHG with continuous air flow is viable technique to reduce the ethanol production cost form molasses at commercial scale.