Acido solfidrico nella letteratura internazionale

Using pharmacological and biochemical approaches, Ca2+ involved in the betulin production in mycelia of Phellinus linteus induced by hydrogen sulfide (H2S) were investigated. The results showed that 2 mM H2S donor NaHS or 10 mM CaCl2 was found to enhance the betulin content in the mycelia of Phellinus to the maximum, which were 112.43 and 93.24 % higher than that in the control, respectively. Further, NaHS and CaCl2 co-treatment also showed positive outcome, which were 128.95 or 24.52 % higher than that in the control or NaHS treatment. At the same time, NaHS also enhanced the content of Ca2+ and CaM. But, the above positive inductive effects for Ca2+, CaM, and betulin production can be blocked with either Ca2+ channel blocker (LaCl3, 2-aminoethoxydiphenyl borate) or Ca2+ chelator (ethylenediaminetetraacetic acid (EDTA)). Among of them, betulin content was reduced 35.06 % by NaHS and EGTA to the minimum, and this reduction could be reversed by the application of CaCl2 (NaHS + EGTA + CaCl2). From above results, it can be concluded that endogenous and exogenous calcium involved in the betulin production from submerged culture of P. linteus induced by hydrogen sulfide (27) El-Baz AF, Sorour NM, Shetaia YM. Trichosporon jirovecii-mediated synthesis of cadmium sulfide nanoparticles. J Basic Microbiol 2015 Oct 15. Abstract: Cadmium sulphide is one of the most promising materials for solar cells and of great interest due to its useful applications in photonics and electronics, thus the development of bio-mediated synthesis of cadmium sulphide nanoparticles (CdS NPs) is one of the essential areas in nanoparticles. The present study demonstrates for the first time the eco-friendly biosynthesis of CdS NPs using the yeast Trichosporon jirovecii. The biosynthesis of CdS NPs were confirmed by UV-Vis spectrum and characterized by X-ray diffraction assay and electron microscopy. Scanning and transmission electron microscope analyses shows the formation of spherical CdS NPs with a size range of about 6-15 nm with a mean Cd:S molar ratio of 1.0:0.98. T. jirovecii produced hydrogen sulfide on cysteine containing medium confirmed by positive cysteine-desulfhydrase activity and the colony color turned yellow on 0.1 mM cadmium containing medium. T. jirovecii tolerance to cadmium was increased by the UV treatment and three 0.6 mM cadmium tolerant mutants were generated upon the UV radiation treatment. The overall results indicated that T. jirovecii could tolerate cadmium toxicity by its conversion into CdS NPs on cysteine containing medium using cysteine-desulfhydrase as a defense response mechanism (28) Carter RN, Morton NM. Cysteine and hydrogen sulfide in the regulation of metabolism: Insights from genetics and pharmacology. J Pathol 2015 Oct 15. Abstract: Obesity and diabetes represent a significant and escalating worldwide health burden. These conditions are characterized by abnormal nutrient homeostasis. One such perturbation is altered metabolism of the sulfur-containing amino acid cysteine. Obesity is associated with elevated plasma cysteine, whereas diabetes is associated with reduced cysteine levels. One mechanism by which cysteine may act is through its enzymatic