Beesioside Q is a natural product extracted from the rhizome of Beesia calthaefolia (Maxim.) Ulbr.

Spantide I, a substance P analog, is a selective NK1 receptor antagonist, with Ki values of 230 nM and 8150 nM for NK1 and NK2 receptor, respectively. Spantide I provides an approach to reduce type 1 and enhance the type 2 cytokine IL-10 in the infected cornea, leading to a significant reduction in corneal perforation.

3-methylthiopropionate is one of the metabolites of methionine (especially of D-methionine). Cultures of Streptomyces lincolnensis accumulated 3-methylthioacrylic acid in amounts directly related to the concentration of methionine in the medium. The first intermediate in the pathway may be the keto acid which is then oxidatively decarboxylated to 3-methylthiopropionic acid.