| Summary: | 碩士 === 元智大學 === 化學工程與材料科學學系 === 94 === Study the separation intracellular of PHA from Cupriavidus taiwanensis184, Buskholderia sp.PTU9, Pseudomonas.Putida.KT2442, Escherichia coli. Cell disruption was used heat、homogenizer、sonicator and chemical at pretreatment. Separation and purification of PHAs was included solvent extraction, alkaline(sodium hydroxide, potassium hydroxide), sodium hypochlorite, sodium hypochlorite- sodium dodecyl sulfate, enzyme-sodium hypochlorite. The purity, recovery, molecular weight and thermal property of PHAs was determined as well.
The optimal recovery condition were heat pretreatment and 50°C、125rpm、5min of reaction time with 4cm3 sodium hypochlorite. Under such condition, a purity of 99%, a recovery of 94% and Mw of 1,350,000 were obtained from Cupriavidus taiwanensis184. And melting point of PHB was 178oC.
Crude cell were pretreatment with 50°C, 125rpm, 5min of reaction time with 5cm3 SDS. The optimal recovery condition were 50°C, 125rpm, 5min of reaction time with 5cm3 1N sodium hydroxide from Recombinant E. coli strain. The purity and recovery were 99% and 96%. The Mw was 310,000. And melting point of PHB was 178.2oC
The PHB purity and recovery was 89% and 78% from Buskholderia sp.PTU9, using enzyme-sodium hypochlorite method. Crude cell were heat pretreatment. Digestion used 1cm3 1% papain digest with 40°C, 150rpm, time 1hr .After enzymatic, digesting with 4cm3 sodium hypochlorite at 50°C, 125rpm, 5min of reaction time. And melting point of PHB is 169oC. The Mw was 480,000
The melting point of PHB was 41oC, using 35cm3 sodium hypochlorite digestion at 50°C、125rpm、5min of reaction time form P.putida.KT2442 strain. The purity and recovery were 99% and 78%. The Mw was 53,000.
For molecular weight of PHB from Cupriavidus taiwanensis184. The operating condition, such as different solvents, temperature, amount of sodium hypochlorite and culture condition (media, carbon and nitrogen ratio) were investigated to obtain various molecular weight.
For molecular weight reacted different temperature were 30oC of 1,400,000、50oC of 1,310,000, 80oC of 1,200,000, 100oC of 960,000 from Cupriavidus taiwanensis184. The molecular weight reacted different sodium hypochlorite amount were 5cm3 of 860,000, 10cm3 of 560,000, 15cm3 of 220,000. The membrane used hot press for Mw over 500,000 from Cupriavidus taiwanensis184. Cupriavidus taiwanensis184 was cultured at different carbon source, carbon and nitrogen ratio, was not effect molecular weight. The Mw was about 1,500,000
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