ABSTRACT: This article describes the inhibitory effects of extracts from 25 plants harvested in Sri Lanka against tyrosinase and collagenase. Inhibitors of these enzymes are common ingredients in cosmetics and medications, which help protect the skin against hyperpigmentation and premature aging. The article also discusses the polyphenol content of the extracts, which is well known to possess antioxidant properties. The extract data from the following plants, which have a long history in Sri Lankan traditional medicine, such as Ayurveda, have been provided: English name, "local name in Sri Lanka," (scientific name). Indian copperleaf plant, "kuppameniya," (Acalypha indica); red sandalwood, "madatiya", (Adenanthera pavonina); balipoovu plant, "polpala," (Aerva lanata); snap ginger, "heen araththa," (Alpinia calcarata); bael fruit, "beli," (Aegle marmelos); coastal waterhyssop, "lunuwila," (Bacopa monnieri); porcupine flower, "katu karandu," (Barleria prionitis); balloon-vine plant, "wel penera," (Cardiospermum halicacabum); water caltrop, "Katupila," (Flueggea leucopyrus); Indian sarsparilla, "iramusu," (Hemidesmus indicus); malabar nut plant, "adhatoda," (Justicia adhatoda); wood apple, "divul," (Limonia acidissima); holy basil plant, "maduruthala," (Ocimum tenuiflorum); emblic myrobalan plant, "nelli," (Phyllanthus emblica); long pepper plant,"thippili," (Piper longum); country borage plant, "kapparawalliya," (Plectranthus amboinicus); common sesban, "wel murunga," (Sesbania sesban); turkey berry, "gona batu," (Solanum rudepannum Dunal); purple fruited pea eggplant,"welthibbatu," (Solanum trilobatum); black plum, "madan," (Syzygium cumini); crape jasmine, "wathusudda," (Tabernaemontana divaricate); purple tephrosia, "pila," (Tephrosia purpurea); Chinese chaste tree, "nika," (Vitex negundo); and arctic snow, "suduidda," (Wrightia antidysenterica). The inhibitory effects of these plant extracts on tyrosinase and collagenase, as well as polyphenol contents in the extracts, are detailed in Table 1.
