Isolation and elucidation of antiirritant and antimicrobial bioactives derived from plant sources and from human sebum

Authors: WILLE, JOHN - Bioplast Medical, Llc; Berhow, Mark

Submitted to: Elsevier
Publication Type: Book / Chapter
Publication Acceptance Date: 11/5/2018
Publication Date: 2/4/2019
Citation: Wille, J.J., Berhow, M.A. 2019. Isolation and elucidation of antiirritant and antimicrobial bioactives derived from plant sources and from human sebum. In Attu-ur-Rahman, editor. Bioactive Natural Products, Volume 62, Studies in Natural Product Chemistry. Amsterdam, The Netherlands, Oxford, England and Cambridge, England: Elsevier. p. 411-432.
DOI: https://doi.org/10.1016/B978-0-444-64185-4.00011-3

Interpretive Summary:

Technical Abstract: This chapter will cover recent discoveries of novel bioactives derived from ripe autumn olive berries (Elaeagnus umbellata), ripened corn plant tassels, and a novel human skin fatty acid, presented in the context of both patent and research literature. Ripe autumn olive berries are edible for humans and wildlife, but they have not been commercialized. These berries are one of the richest known sources of lycopene. Aqueous alcoholic extracts, containing phenolic compounds, displayed potent antioxidant and antimicrobial bioactives. High-pressure liquid chromatography (HPLC) studies identified that the dominant components were cinnamic acid and two other hydroxylated cinnamic acid derivatives, p-coumaric acid and ferulic acid, which were responsible for their antioxidant and antimicrobial activities. Corn tassels are the male part of the corn plant, which at approximately 6-8 weeks after planting corn seeds in North America emit a mild fragrance during the ripening process and often coincides with a change in color from green to red. Cold aqueous alcoholic extraction of the tassel spikelets yields a straw-colored solution that retains the characteristic sweet-smelling fragrance. HPLC chromatography resolved an unusual predominant compound, later isolated and identified as 4-hydroxyl-1-oxindole-3-acetic acid. Further biochemical and biological characterization revealed that this compound displays several useful medicinal and cosmetic properties, including potent antiirritant activity and antityrosinase enzyme activity with potential usefulness as a skin whitener. It also possesses good antibacterial and antimold activity. Alcoholic extracts from human hair clippings identified a unique isomer of palmitoleic acid (C16: 1 delta 6 isomer), found only in human skin. Microbiological tests have shown that this compound is the most potent antibacterial fatty acid in human sebum directed against Gram-positive bacteria, including Staphylococcus aureus and the more pathogenic MRSA (methicillin-resistant S. aureus) isolates. Further studies have demonstrated that this palmitoleic acid isomer can be made into a full-spectrum antibacterial agent by combining it with a low concentration of isopropyl alcohol. In summary, diverse natural sources yielded novel compounds with a range of commercially relevant cosmetic and medicinal properties.