Hasil Pencarian  ::  Simpan CSV :: Kembali

"Keberhasilan produksi apoptin rekombinan dalam bentuk native pada penelitian sebelumnya (Khalid, 2012) membuka jalan untuk mengembangkan produksi protein antikanker ini ke skala yang lebih besar. Di dalam studi ini, dilakukan optimasi kultivasi bakteri rekombinan apoptin dalam stirred tank fermentor dan bakteri yang digunakan adalah bakteri Bacillus subtilis 168 rekombinan apoptin hasil transformasi dengan sistem Gateway menggunakan plasmid pOXGW12His8Arg. Parameter yang dioptimasi adalah konsentrasi induksi xylose, kecepatan agitasi dan laju aerasi. Variasi konsentrasi induksi xylose dilakukan dalam shake flasks dengan volume kultur 100 ml dengan konsentrasi 0-5% b/v sedangkan variasi kecepatan agitasi dan laju aerasi dilakukan dalam stirred tank fermentor dengan volume kultur 3L dengan kecepatan dan laju masing-masing adalah 150-250 rpm dan 0,5-1,5 NL/min. Hasil yang didapat adalah pertumbuhan bakteri optimum dicapai pada konsentrasi xylose 1% b/v, kecepatan agitasi 250 rpm, dan laju aerasi 1,5 NL/min dengan nilai laju pertumbuhan spesifik bakteri untuk masing-masing variasi adalah 0,628 h-1; 0,630 h-1; dan 0,747 h-1.

---

The success of recombinan apoptin production in native form in the previous research (Khalid, 2012) open the way to develop this anticancer protein production to the larger scale. In this study, optimization of recombinant apoptin bacteria cultivation is carried out in a stirred tank fermentor using Bacillus subtilis 168 with plamid pOXGW12His8Arg which transformed by Gateway method. The optimized parameters are xylose-inducer concentration, agitation speed, and aeration rate. The xylose-inducer concentration variation is carried out in a shake flasks with 100 ml volume broth, while the agitation speed and aeration rate variation is carried out in a stirred tank fermentor with 3L volume broth. The xylose concentration is varied between 0-5% w/v, while agitation speed and aeration rate are varied between 150-250 rpm and 0,5-1,5 NL/min respectively. The best condition in this cultivation is 1% w/v of xylose, 250 rpm of agitation speed and 1,5 NL/min of aeration rate giving the specific growth rate value for each parameter of 0,628 h-1; 0,630 h-1; dan 0,747 h-1 respectively."

"ABSTRACTXylitol is a five-carbon polyol sugar. It has many healthy benefits and is widely used in food, pharmaceutical, and healthcare. Natural sources with abundant carbon such as lignocellulose can be used for xylitol production. One of the potencial sources with high prevalency in Indonesia is water hyacinth. It is known as weeds and has not been fully utilized by people. The aim of this research was the utilization of water hyacinth which contains hemicellulose as a substrate in the bioconversion of xylose into xylitol by yeast cells Debaryomyces hansenii. Stages of processing include the optimization of water hyacinth hydrolysis using autohydrolysis method and optimization of fermentation conditions. Xylose and xylitol were determined by HPLC with RI detector and LiChrosorb® NH2 (4 mm x 125,00 mm, 5μm) column. Acetonitrile-water (90:10, v/v) was used as a solvent. 20 μL sample volume was injected at flow rate of 1.0 mL/min and room temperature. The results showed that optimum conditions for the acquisition of xylose were obtained through autohydrolysis methods for 75 minutes with 1:15 water hyacinth and water ratio and posthydrolysis for 45 min using 4% sulfuric acid. Xylose concentration in hydrolyzate obtained was 25.55 g/L. The optimum fermentation condition for xylitol production was achieved by four day cultivation, limited aeration condition, and addition of metal ions CaCl2.2H2O 0.01%. The yield of xylitol obtained using those conditions was 77.43 %. "

"ABSTRACTXylitol is five-carbon polyol sugar which widely used as a sweetener in food and pharmaceutical.Xylitol production by chemical procedures using high pressure and temperature also neededextensive purification are less cost-effective in production. Fermentation which has more advantageswith lower cost due tocheaper substrate and the non-necessity of xylose purification. The purposes ofthis research were to find optimum condition for xylitol production with particular variable such assubstrate concentration, aeration, methanol and nitrogen sources addition. Oil palm empty fruitbunch hydrolyzates containing xylose was fermented into xylitol by Debaryomyces hansenii UICC Y-276 at room temperature. Fermentation was carried out at 200 rpm for 72 hours. Then, xylose andxylitol were determined by HPLC with RI detector and LiChrosorb® NH2 (4 mm x 125,00 mm, 5μm)column. Acetonitrile-water was used as a solvent, 20 mL sample volume was injected at flow rate of1,0 mL/min at room temperature. The optimum fermentation conditions was obtained in a state ofsemi-anaerobic condition (1 : 2.5) with 10,0 % (w/v) xylose concentration. Meanwhile with theaddition of various concentration of methanol and nitrogen sources, it was obtained that 1,5 %methanol and 0,5 % ammonium sulfate gave high yield of xylitol production. The best result for yieldxylitol production was 31,83 %."