sulphur brands

Molecular formula: S

Topically applied sulfur has mild antifungal and antibacterial activity. It has been suggested that when applied topically to the skin, sulfur forms hydrogen sulfide and/or polythionic acid, which may exert germicidal activity. In vitro studies indicate that sulfur has little if any fungistatic or fungicidal activity. Therefore, sulfur's antifungal activity probably results largely from its keratolytic action, causing shedding of fungal spores and hyphae embedded within the stratum corneum. In vitro, sulfur has been shown to have some antibacterial activity; the drug has a potent inhibitory effect against some streptococci, a moderate inhibitory effect against Staphylococcus aureus, and no activity against gram-negative bacteria. It has been suggested that the drug's antibacterial activity may partly result from inactivation of sulfhydryl groups contained in bacterial enzyme systems, since the antibacterial effect of the drug has reportedly been neutralized by addition of cysteine and other sulfhydryl-containing compounds to the culture medium. Topically applied sulfur is reportedly toxic to the parasitic arthropod Sarcoptes scabiei. The exact mechanism(s) of action of "sulfur" in the treatment of acne is not fully understood but is presumed to involve the drug's keratolytic and antibacterial effects. Although some studies indicate that "sulfur" may also be comedogenic, other studies have been unable to substantiate this effect and the drug generally is considered effective in the topical treatment of acne. The aim of this research was to analyze the effects and the modes of action of elemental sulfur (S(0)) in bioluminescence and respiration of Vibrio fischeri cells and the enzymes crude luciferase, pure catalase, and alcohol dehydrogenase (ADH). Metallic copper removed sulfur and reduced the toxicity of acetone extracts of sediment samples analyzed in the bioluminescence test. The sulfur inhibition of cell bioluminescence was noncompetitive with decanal, the luciferase substrate; reversible, with maximum toxicity after 15 min (EC50 = 11.8 ug/L); and almost totally recovered after 2 hr. In vitro preincubation of crude luciferase extract with sulfur (0.28 ppm) weakly inhibited bioluminescence at 5 min, but at 30 min the inhibition reached 60%. Increasing the concentration of sulfur in the parts per million concentration range in vitro decreased bioluminescence, which was not constant, but depended on exposure time, and no dead-end/total inhibition was observed. The redox state of enzymes in the in vitro system significantly affected inhibition. Hydrogen peroxide restored fully and the reducing agent dithiothreitol, itself toxic, restored only partially luciferase activity in the presence of sulfur. Sulfur (5.5 ppm) slightly inhibited ADH and catalase, and dithiothreitol enhanced sulfur inhibition. High sulfur concentrations (2.2 ppm) inhibited the bioluminescence and enhanced the respiration rate of V. fischeri cells. Elemental sulfur data were interpreted to show that sulfur acted on at least a few V. fischeri cell sites: reversibly modifying luciferase at sites sensitive to/protected by oxidative and reducing agents and by affecting electron transport processes, resulting in enhanced oxygen consumption. Sulfur together with an enzyme reducing agent inhibited the oxidoreductive enzymes ADH and catalase, which have /thiol/ groups, metal ion cofactors, or heme, respectively, in their active centers. Sulfur must be converted to pentathionic acid (H2S5O6) in order to exert germicidal action. Presumably oxidation of sulfur to pentathionic acid is accomplished by certain microorganisms or by epidermal cells when element is applied to skin. Sulfur possesses a keratolytic property, which may be the basis for the therapeutic action of the element in certain cutaneous disorders unassociated with infection.

Source: PubChem (NCBI) · compound 5362487