Gliadin was reacted with citric acid under weak acidic and weak alkaline conditions in both wet and dry states and the reaction mechanism was studied. The low morphological stability in an aqueous environment and inferior mechanical properties have restricted the applications of plant proteins, although these materials possess a unique structure, biocompatibility and biodegradability. Carboxyli...

The mutant strain of Aspergillus niger NG-110 was evaluated for the present investigation of citric acid production. The cultural conditions optimized during the course of study were pH and K4Fe(CN)6, K2HPO4 and CaCl2 concentrations. Cane-molasses was utilized as the basal fermentation medium. The mutant NG-110 produces maximal amount of citric acid when the pH of the medium was 6. When the con...

The total acidity of orange juice is ordinarily determined by titrating a known volume of juice with a standard solution of NaOH, with phenolphthalein as indicator, the result beinog expressed as citric acid. This value includes all the substanees of an acidic nature in the juice that react with NaOH. It so happens, however, that in most fruits the chief substances reacting with NaOH are the or...

A study was conducted to determine the additive effects of calcium (Ca) levels and the enzyme phytase, organic acids (citric, ascorbic acid), vitamin D on broiler performance and nutrient digestibility (d 3 1 to 21) in wheat-based diet. Broilers were fed the following diets at either 7.9, or 9 g/kg of dietary Ca with: 1) a negative control wheat-based diet, 3.15 g/kg available phosphorus (P) (N...

The removal of heavy metal from sludge before disposal or application to farmland is a necessary step to achieve a more safe sludge usage or disposal. Chemical extraction using inorganic acids (nitric, hydrochloric) and organic acids (citric, oxalic) were tested for extraction of chromium, copper, nickel, lead and zinc from contaminated sewage sludge at different pH and reaction time. Results r...

2.2 Significance of decarboxylation 2.2.1 Role in biosynthetic pathways In the biochemical milieu, decarboxylation is a ubiquitous step for transformation of amino acids into various other secondary metabolites using specific enzymes termed decarboxylases [Liu and Zhang (2006)]. More importantly, nature has also employed decarboxylation as a central tool for linking metabolic pathways like glyc...

oxaloacetate +pyruvate ci 8-acontate = ocitrat. In order to be able to examine the new hypothesis we have worked out methods for the micro-determination of ci8-aoonitic and i8ocitric acids, a preliminary account ofwhich has been published in the Proceedings of the Biochemical Society (Krebs & Eggleston, 1943 b). So far no specific micro-methods for the estimation of the two. acids have been des...

In view of the often-cited theory that citric acid accumulation is caused by an inhibition of aconitase activity, the equilibrium of the reaction of aconitase was investigated by comparing in vivo steady-state concentrations of citrate and isocitrate in Aspergillus niger grown under various citric acid-producing conditions. With the equilibrium catalyzed by the A. niger enzyme in vitro, similar...

zinc­ (zn) is an essential micro­nutrient needed by plants, animals and humans. bioavailability of zn to plant root is controlled through sorption process in soils. to evaluate the effect of citric acid on zn sorption,­ a batch experiment was conducted with two soil samples (s1, s2), that differed in their clay and calcium carbonate contents. three levels of citric acid (0,­ 0.5, 1 mm) and twel...