| PHA (polyhydroxyalkanoate) is only a kind of thermosplastic biomacromolecule material from biosynthesis by microorganism in the present world. PHA, comparing chemical synthesis plastics,has good thermosplasticity, easy to process and application universality, also has complete degradability, good biological compatibility, piezoelectric that the chemical synthesis plastic does not . Therefore, PHA substitute for chemical synthesis plastics, eliminates the white pollution and has the widespread applied high polymer material in future.At the present time, key question of carring on the big production for PHA is high production cost in comparison with chemosynthesis,so the cost of production for PHA is a key problem.Production costs for PHA, by two parts of constitutions, namely fermentation and PHA extraction. This topic in earlier period research, through two bacterium mixture for high density raise, causes the fermentation biomass to reach the 53g/L, the output of PHA to reach 42.4g/L, reduce production costs of the fermentation process section effectively. But ,extraction craft of PHA occupied 70% at the PHA total production cost is also puzzling industrial production advancement for PHA. Therefore, the research explores the new PHA extract craft, reduce the production cost large scale of extraction craft section, which is this paper research essential target.Through experiments of the extraction of PHA ,we have adopted four methods (1) the purity and recover of PHA are 95.2% and 87% by fierce puddle process in 20 min.(2) the purity and recover of PHA are 96% and 88.9% through 1% SDS in 15 min, and 30%(V/V) NaCLO in 3 min.(3) the purity and recover of PHA are 97.2% and 83% ,by the temperature 62℃, the rotational speed (600rpm), the chloroform dissolution stirs in 2 hours in seal.(4) the purity and recover of PHA are 98.4% and 85.4% when the KOH density is 0.2N, and temperature 30℃in 30min,finally dissolves after the chloroform.Through comparison during above-mentioned extraction methods, "the seal backflow puddle process", was considered that has the prospects for PHA production. This method not only retained the high efficiency of chloroform extraction, is most the chloroform recycling redundant use, effectively reduce the production cost for PHA more importantly, also reduce the chloroform to operators' toxic action, has avoided the production to the environment pollution. At the same time, this way is also contribute to industrial production equipment shaping, has laid the technology base.The product come from extraction ,although the purity is good, but the color is deep, and the transparency is bad. Therefore the experiment carries on decolorization processing, that selects NaCLO to decolorize, the sodium hydrosulfite (Na2S2O4) decolorizes, the activated charcoal decolorizes, through the three methods ,finally demonstrated that the activated charcoal decolorization effection is best, the product transparency which obtained is good, to enlarge possibility of application in the medical fieldSince 1992 ,our country discovered that "Unclear organism" in the Wei River sandbank of Shanxi in the first time, many times has presented the related unclear organism in recent years .After the preliminary study, people discovered that it includes massive microorganisms and slime-mold carpophore and many kinds of mycelial fungi and bacterium, therefore is called that organism "the large-scale slime-mold complex" temporarily. But in the research we discovered that collects this unclear object's exudation, flattens dry after a plate, becomes one piece to have certain toughness, and the translucent plastic shape material. Adds the slime-mold is produces another kind of biomacromolecule material - to gather the malic acid mold mushroom spawn. This stimulated the author take more interest for"Unclear organism" researchIn the research we attempts to usemany kinds of resolver and many kinds of methods, carries on the dissolution to the unclear object, finally discovered that 60℃-70℃of the hot water may dissolve Unclear organism fully.Water dissolved matters of "Unclear organism" I is exstracted by n-butanol, Extract fluid and mother liquor is treated separately throughcolumnchromatographic analysis and Ethyl alcohol precipitation, get some compounds and one kind of main matter of White precipitation. White precipitation through removal of lipids and proteins,and desalination,determine the basic component for PVA , And through the NMR, IR, and other elemental analysis and comprehensive analysis. Similarly, get a white sediments after "unknown objects" II was processed, after analysis by infrared control, the basic material for PVA. The experimental results show thatl992 Shaanxi discovered the first case of " sample" I and Hebei in 2005 found " sample" II are polyvinyl alcohol which contain Polysaccharide with a small amount of material, a visco-and mixed bacteria, fungi and bacteria Bacillus, does not include poly- malic acid. This unclear organism. is the people discarded to the natural educational world reject? Is also the metabolin of microorganism?, At present ,we has not been able to obtain correct answers according to present conclusions. |
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