A new polymorph of ammonium succinate – serendipity in action

Succinic acid has been known since 1546 and was first chemically identified in the mid-19th century. In an attempt to prepare a molecular salt of succinic acid with (S)-(−)-α-methylbenzylamine, we have obtained the second polymorph of the monoammonium salt of succinic acid, NH4 +·C4H5O4 −. The crystal structure determination proves the structure of the ionic compound and the intimate role of the ammonium ion in the structure, which is compared to the earlier described polymorph.

SUBSTITUTION COMPONENT CULTIVATION MEDIA OF PHOTO-FERMENTATION PROCESS FOR LOW COST HYDROGEN GAS BIOPRODUCTION

Employing the Rhodobium marinum bacteria as an agent of hydrogen bioproduction with facultative fermentation condition needs two steps of cultivations, i.e., pre-culture and hydrogen production periods with different media. The two steps cultivation is important state for hydrogen gas production rate. ASY (Ammonium, Succinate, and Yeast extract) is usually used as standard medium in biohydrogen production and mostly the component is analytical grade of chemicals. Series of cultivation media substitution by combining ASY with other cost-effective chemicals were investigated. The total of sixteen combinations of media were observed (P0-P15). Cultivation condition of R. marinum was set in an illuminated light of 31.17 µmol s-1m-2photon and agitated in shaker of 120 rpm for nine days. The experiment was designed as random selection with anova analyses. The results exhibited that P7 medium combination released the highest hydrogen gas of 61.29±0.52 ml/80 ml media among the others combination media. Using one-way ANOVA, there was a statistically significant difference between the mean number and condition and it was found P7 was significantly different with the others combination media, except P7 was insignificantly different with P3 only. Overall, the combination media is cheaper than the ASY medium. The ASY medium price is about USD 677, and the substitution media prices were ranging from USD 4.24 to USD 613.47. However, the further research on optimisation cultivation condition is needed.

CLAVINE ALKALOID FORMATION IN SUBMERGED CULTURES OF A CLAVICEPS SPECIES

The role of major nutrients in a glucose – mannitol – ammonium succinate – mineral salts medium which supports high production of clavine alkaloids was examined. Mannitol was found to be superior to other carbohydrates as a source of carbon but, under certain conditions, could be partially replaced with glucose. Ammonia provided the most suitable source of nitrogen, and was best supplied as ammonium succinate. In media with glucose and mannitol as principal carbon source, ammonium and succinate ions were utilized at parallel rates, maintaining the pH of the culture within the favorable range of 5.5–6.5 during alkaloid formation. For maximum yields there were optimum values for the initial concentrations of ammonia and phosphate in the medium. The concentration of phosphate required was growth-limiting. A high carbon:nitrogen ratio was necessary to prolong the phase of alkaloid synthesis. Production was increased by the "addition of L-tryptophan but not DL-mevalonic acid. The advantages of this medium for promoting alkaloid formation appear to be limited to clavine-producing strains isolated from Pennisetum typhoideum.