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China is one of the largest countries of the world apple production, of which about 20% for fruit juice processing, can produce pomace 100 million tons. Currently, the pomace in addition to a small amount is used for fuel, fertilizer and deep processing, most abandoned. Not only a waste of resources and serious pollution of the environment. Therefore, the development and utilization of apple pomace feed resource development has become an important issue. This paper studies the feasibility of pomace mixed as raw material by solid-state fermentation production of composite enzyme and fermentation process of cellulase, xylanase and pectinase activity analysis, the main results are as follows: 1 the pomace main ingredient peel pulp accounted for 96.2%, 3.1% fruit seed, accounted for 0.7% of the stems. Pomace containing nitrogen free extract 61.5% and 12.3% of the total sugar, fat 6.2%, crude protein content of 5.6%, sugar 11.4%, 0.5% fructose, sucrose 0.5%, 0.52% of the total acid, 31.8% oleic acid, sub oleic acid 33.5% Sodium 454.72 mg / kg, 0.436% potassium. 2. Three kinds of optimization of the assay conditions for the pomace produced by fermentation of complex enzymes in the cellulase, xylanase, pectinase, and three kinds of enzyme activity determination method exploring optimal determination of the three enzyme activities wavelength scan DNS increase the amount of enzyme solution added amount of the substrate, reaction time, reaction temperature, and the boiling time of the single factor analysis, and ultimately determine the various parameters of the measurement conditions: the measurement wavelength of the three enzyme activities are selected to 480 nm, measured temperature 40oC, pH of 5.0, plus the amount of substrate and enzyme solution of 2 ml each blank choose to terminate the blank. Determination of cellulase enzyme substrate concentration of 10 g / l, the enzymatic reaction time of 10 min; the xylan substrate concentration is 10 g / l, and the reaction time is 15 min; the pectinase substrates optimum concentration of 0.8 g / l, reaction time 15 min. Determine the fermentation cycle of solid-state fermentation medium is determined to be 48 h; ratio of water identified as 1:1.2; from the fermentation second day began daily replenishment of 1.0 ml, timely replenishment have a certain effect on the enzyme activity increases. By single factor test and orthogonal test the effects of different nitrogen sources on the solid-state fermentation of apple pomace, and determine solid medium fermented apple recipe: ammonium sulfate 2.0% dipotassium hydrogen phosphate, 0.1%, 2.5% urea Marc: bran = 4:1. 4. choice of mixed strains 10 fungal strains, the solid plate screening and rescreening of solid-state fermentation enzyme assays, elect a higher activity of several bacteria. Observation to determine whether antagonism between the bacteria strains screened using the method of cross-crossed. No antagonism bacteria mixed culture solid-state fermentation, C-2, C-6 and Asp-1 mixed bacteria after experimental best strains for fermentation, after mixing the three enzyme activities as a whole has been improved, compared to single strain a higher activity of unity, mixed bacteria due to the synergy between the bacteria to reach the expected mixed effect. Screened three bacteria mixed fermentation conditions optimization, optimal activity ratio using orthogonal test to optimize elected three strains mixing ratio, fermentation temperature, sample loading amount, seeded # 2 spawn time amount of # 2 seeded # 3 spawn time, vaccination, inoculation amount # 3. Test concluded: fermentation temperature of 30 oC; the flask capacity 250 ml; select strains # 1, # 2, # 3, while the inoculation # 1 volume of 1 ml; vaccination # 2 volume 2 ml; inoculation # 3 Volume 1 ml. Research the optimum temperature of the enzyme on the nature of the activity of three enzymes: cellulase optimum reaction temperature of 70oC, above or below this temperature enzyme activity decreased. Xylanase optimum temperature is 55 oC, The pectinase optimum temperature is 45 oC. The thermal stability of the enzyme: the thermal stability of the cellulase is relatively high, at 60 oC for 30 min enzyme activity remained at 80% or more, and then increased the temperature was seen to decline in apparent enzyme activity; xylanases at 40 oC relatively stable under the conditions of no loss of enzyme activity, a smaller loss of 50 oC enzyme activity, the residual activity of 76.72%, 17.35% residual activity only to 60 oC; pectinase enzyme 50 oC stable best between 30-60 oC activity is maintained at more than 70%. The optimum pH of the enzyme: cellulase optimum pH 4.6, the optimum pH of the xylanase and pectinase are 4.4 and 5.0. The relative activity of more than 60% within the range of pH4.2-5.4, Laboratory of these three enzymes is an acidic enzyme inactivation under acidic conditions is not easy. The pH stability of the enzyme: pectinase is relatively stable under the conditions of pH 4-5, with substantially no loss of enzyme activity, the residual enzyme activity in more than 90% in the pH 3-6 range; xylanase pH4.5 conditions are relatively stable, with substantially no loss of enzyme activity, the residual activity is maintained at more than 85% in the pH 3.5-6.0 range, outside this range, no greater loss in enzyme activity. Cellulase stability better than the xylanase, pH 3.0-8.0 are not greater losses, the residual activity at 90% or more.
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