Effect of some nutrients on alginate synthesis in azotobacter vinelandii and characterization of the produced alginate

The role of nutrients on alginate production by A. vinelandii was studied in batch cultures. The largest amount of bacterial alginate was obtained in presence of: 0.3 g/t MgSO[4-].7H[2]O, 0.4g/l NaCI, 42mg/I CaCl[2]. 2H[2]O, 4mg/I K[2]HPO[4], 16mg/I K[2]HPO[4], 2.5mg/1 FeSO[4-]7H[2]O, 2.9mg/I H[3]BO[3], 2mg/1 ZnSO[4], 7H[2]O, 2mg/I Na[2]MoO[4]. 2H[2]O, 0.3mg/I CuSO[4-],. 5H[2]O, 0.2mg/I MnCI[2]. 4H[2]O. Alginate production was not enhanced by natural additives or inducing agents except for acetate which increase alginate yield. The pure alginate contained 0.36% ash and 0.4% protein. It is similar to algal alginate but has an extra acetyl group. It contains 69.5% M-M block, 27.5% M-G block and 3% G-G block

Effect of some nutrients on riboflavin formation by aspergillus terreus

Riboflavin formation by Aspergillus terreus was investigated. In order to examine the effects of different substrates, molasses was used with a combination of different levels of corn steep solid or peptone. The yield of riboflavin was not affected by the elements content of molasses. The maximum yield of riboflavin was obtained in the medium which contained 9% centrifuged molasses and 0.1% corn steep solid. The presence of 1.5 g/l oleic acid and 0.2 g/l serine greatly enhanced the vitamin productivity

Riboflavin production by aspergillus terreus from beet-molasses

Aspergillus terreus was used for riboflavin [vitamin B[2] production in a media containing beet molasses as the sole carbon source. The growth and vitamin production of the fungus were markedly affected by the composition of the culture medium. Maximum riboflavin yield was achieved at the late exponential growth phase [16 days old cultures], in presence of [g/1]: centrifuged beet-molasses, 90; L-asparagine. 1: MgSO[4]. 7H[2]O. 0.5; K[2]HPO[4]+]KH[2PO[4] [1:1], 5 -and the medium initially adjusted to pH 8

Degradation of shrimp-shell waste and production of chitinase by bacillus amyloliquefaciens under some cultural conditions

The study of chitinase production by Bacillus amyloliquefaciens grown on shrimp-shell waste as the sole carbon source showed that chitinase production with maximum enzyme activity was reached when 2% inoculum of 24 h age seed culture was used. The inoculated medium contained [g/I] shrimpshell waste, 80; NH[4]CI, 1.2: KH[2]PO [4]; K[2]HPO[4], 1.6; MgSO[4].7H[2]O, 0.1: ZnSO[4]. 7H[2]O, 0.1; ZnSO[4] .7H[2]O. FeCI[3]. 6H[2]O, 0.01; CaCI[2]2]H[2]O, 0.02 at pH 7 and the culture shaken at 30°C for 36 hours

Some factors influencing chitinase production by bacillus amyloliquefaciens

The effect of several analogues and breakdown products of chitin on the iodsetioa of the chitinase of B. amyloliquefaciens was examined. Glucose. N -acetyl-glucosamine and chitobiose inhibited the enzyme productivity. The effect of the addition of some natural extracts was also investigated and the maximum enzyme activity was produced with 2% sand extract. A simplified medium composed of 8% shrimp-shell waste and 80% sand extract yielded an enzyme of highest activity. Reaction conditions supporting best activity sum achieved using 5-7-5mg swollen chitin in 0.03 M phosphate buffer at pH 5.916.98; enzyme concentration of 11.35mg protein/reaction mixture and incubating the mixture at 45°C for 60 min

Physiological study on riboflavin production by a hydrocarbon-utilizing candida guilliermondii wickerhamii

The production of riboflavin [Vitamin, B[2]] by Candida quilliermondii wickerham cultivated on solar-containing medium was stimulated in presence of corn oil [0.1g%], arginine, phenylalanine [1 m mole/1] or CoSO[4]. 7H[2]O [1000 ug/I]. On the other hand, emulsifying agents strongly inhibited yeast growth and vitamin production. Similarly, FeSO[4]H[2]O and MnSO[4]. 4H[2]O 50 and 200 ug/1 levels respectively also showed inhibitory effect. Among the tested purines, xanthine enhanced the vitamin production