The chemical composition of snail gelatin

Zooceuticals and Cosmetic Ingredients Derived from Animals

Many substances derived from animals are used as ingredients in the cosmetic industry and constitute a particular type of product: zooceuticals. The main ingredients used can come from insects, such as snail slime; land animals, such as lanolin; and marine animals, such as marine collagen. Today, they are used less than in the past for hygienic–sanitary, ethical, and ecological reasons. Moreover, some can give rise to irritative or allergic dermatitis. However, they still represent a fraction of the common ingredients in certain types of cosmetic products today.

A compilation of amino acid analyses of proteins. XVIII. Residues per thousand residues--5

The amino acid analyses of 213 proteins, as residues per 1000 residues, are given. In addition, the carbohydrate content, the content of any noncommon amino acids, the sources of all proteins, and the necessary literature citations are given.

Invertebrate collagens

The collagens of all major invertebrate phyla have been studied, but characterization has been thorough in only a few classes and in no case in the detail (such as sequence analysis) known for vertebrate collagen. Biochemical data on insect collagen are particularly sparse. Invertebrate and vertebrate collagens are strikingly similar, with some notably unique features in annelids and nematodes. Present data do not support the suggestion that invertebrate collagens resemble vertebrate basement membrane collagen. In invertebrates, as in vertebrates, collagens of specific tissues show differenes that probably reflect individual tissue requirements.

Amino Acid Composition of Some Calcified Proteins

Amino-acid analysis shows that the proteins from two calcified tissues, enamel and snail shell, are related to collagen in that they also contain hydroxylysine . The presence of hydroxyproline is suggested but not confirmed. This evidence, together with other recent findings, suggests that hydroxylysine may have an important role in the calcification of each of these otherwise diverse proteins.

Isolation of Uridine Diphosphate-Glycosyl Compounds from the Slug

An examination of the acidsoluble nucleotides of Limax maximus Linné revealed, among others, several uridine diphosphaté-glycosyl compounds. Nucleotides isolated and identified were the uridine diphosphates of glucose, acetylglucosamine, and acetylgalactosamine.