The quantitative effects of sugar concentration, nitrogen concentration, EDTA, temperature, pH and time of fermentation on ethanol production were optimized using a Box-Wilson central composite design (CCD) experiment. It was found that palmyra jaggery (sugar syrup from the palmyra palm) is a suitable substrate for the production of high concentrations of ethanol using Saccharomyces cerevisiae NCIM 3090 by submerged fermentation. A maximum ethanol concentration of 129.4 g/l was obtained after optimizing media components and conditions of fermentation. The optimum values were a temperature of 26.2°C, pH of 8.4, time of fermentation of 4.2 days with 398.5 g of substrate/l, 3.
Effect of various Physico-Chemical and Nutritional parameter for the production of ethanol from mahua flower using Saccharomyces cerevisiae -3090 through submerged fermentation have been studied. Substrate mahua flower contains 68% Total sugar. Yeast strain S.cerevisiae-3090 was obtained from National Collection of Industrial Microorganisms (NCIM), Pune, South India. Maximum production of ethanol obtained at different optimized parameters such as substrate concentration at 28%, p H at 5.0, Inoculum level at 2%, Inoculum age at 48 hours, Temperature 30 0 c, Urea at 0.06 %, Copper sulphate 3 ppm, Sodium Potassium Tartrate 1.0 g/l and fermentation period is 48 hours is 13.450%(w/v). Effect of Sodium Potassium Tartrate and Urea showed the maximum production of ethanol. It is also conformed that the designed media is suitable for ethanol yield for large scale production.
Statistical experimental design was used to optimize medium constituents and the conditions of fermentation, viz., temperature, pH and the time of fermentation. Higher yields of L-glutamic acid (37.1 kg/m 3 ) was obtained after optimizing medium components and the conditions of fermentation. The optimal levels of medium components were: 61.5575 kg/m 3 glucose, 7.3272 kg/m 3 urea and 1.783 lg/dm 3 biotin. The optimum productivity was achieved using optimized medium at the fermentation temperature of 33.7°C, initial pH 7.74, and at the time of fermentation of 58.4 h.
IntroductionL-glutamic acid has widespread use throughout the world, this amino acid is of special interest because of its¯avour, sweet taste, and acidic character. L-glutamic acid is used as a seasoning agent and as a starting material for the synthesis of various kinds of speciality chemicals [1]. The annual production of monosodium glutamate produced extensively by fermentation exceeds 370,000 tonnes [2]. The study of L-glutamic acid fermentation gained importance because of its wide spread applications in the food and pharmaceutical industry. L-glutamic acid was produced in the earlier days by the acid hydrolysis of wheat glutten or soyabean protein. Over a period of years, L-glutamic acid producing microorganisms were isolated and subsequent research resulted in fermentative process for the production of L-glutamic acid [3]. At present almost all the L-glutamic acid available commercially is being produced by fermentation process [4±5].The present study involves the optimization of medium constituents for the production of L-glutamic acid by coimmobilized whole cells of Pseudomonas reptilivora and Micrococcus glutamicus, followed by the optimization of physical operational variables like initial pH, temperature and time of fermentation. Conventional practice of single factor optimization by keeping other involving factors at unspeci®ed constant level does not depict the combined effect of all the factors involved. Also this method requires to carry out a number of experiments to determine the optimum levels, which are untrue. These drawbacks of single factor optimization process can be eliminated by optimizing all the affecting parameters collectively by statistical experimental design. Experimental design using response surface methodology (RSM) [6±8] was used in the present investigation to optimize the medium constituents and the conditions of fermentation of L-glutamic acid production by coimmobilized whole cells of Psedomonas reptilivora and Micrococcus glutamicus.
Materials and methods
OrganismsPseudomonas reptilivora NCIM 2598 and Micrococcus glutamicus NCIM 2168, obtained from National Chemical Laboratory, Pune, India, were used through out this study.
Growth medium and growth conditionsThe cultures were maintained on agar slants having composition (kg/m 3 ): glucose ± 10, beef extract ± 10, peptone ± 10, NaCl ± 5 and agar agar ± 20. The pH of the medium was adjusted to 7.0 and incubated at 37°C for 36 h. For the seed culture development, ...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.