Aromatic proteinaceous surfactants stabilize longhyphen;lived gas microbubbles from natural sources

摘要

Three different types of proteinhyphen;specific chemical tests were performed on longhyphen;lived gas microbubbles derived from aqueous solutions of agarose powder and from filtered aqueous extracts of Hawaiian forest soil. The separate proteinhyphen;specific tests involved use of either 0.3percnt; (w/v) ninhydrin, 100 mgr;M methylene blue dye, or 0.7ndash;1.0 M 2hyphen;hydroxyhyphen;5hyphen;nitrobenzyl bromide. The chemical test results obtained with each of the two natural substances, i.e., agarose powder and Hawaiian forest soil, were very similar and indicate that the biological surfactants which surround and stabilize longhyphen;lived gas microbubbles are proteinaceous compounds that contain, and whose surface activity depend upon, aromatic amino acid residues, particularly tryptophan.