title: Phenolic Compounds and Antioxidant Activity of Phalaenopsis Orchid Hybrids.
abstract: Phalaenopsis spp. is the most commercially and economically important orchid, but their plant parts are often left unused, which has caused environmental problems. To date, reports on phytochemical analyses were most available on endangered and medicinal orchids. The present study was conducted to determine the total phenolics, total flavonoids, and antioxidant activity of ethanol extracts prepared from leaves and roots of six commercial hybrid Phalaenopsis spp. Leaf extracts of "Chian Xen Queen" contained the highest total phenolics with a value of 11.52 ± 0.43 mg gallic acid equivalent per g dry weight and the highest total flavonoids (4.98 ± 0.27 mg rutin equivalent per g dry weight). The antioxidant activity of root extracts evaluated by DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging assay and β-carotene bleaching method was higher than those of the leaf extracts. Eleven phenolic compounds were identified, namely, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, caffeic acid, syringic acid, vanillin, ferulic acid, sinapic acid, p-coumaric acid, benzoic acid, and ellagic acid. Ferulic, p-coumaric and sinapic acids were concentrated largely in the roots. The results suggested that the root extracts from hybrid Phalaenopsis spp. could be a potential source of natural antioxidants. This study also helps to reduce the amount of this orchid waste in industrial production, as its roots can be exploited for pharmaceutical purposes.
authors.affiliation: Graduate School for International Development and Cooperation, Hiroshima University, Hiroshima 739-8529, Japan. minhtn689@gmail.com.
authors.forename: Truong Ngoc
authors.initials: TN
authors.lastname: Minh
authors.affiliation: Graduate School for International Development and Cooperation, Hiroshima University, Hiroshima 739-8529, Japan. dtkhang@ctu.edu.vn.
authors.forename: Do Tan
authors.initials: do T
authors.lastname: Khang
authors.affiliation: Graduate School for International Development and Cooperation, Hiroshima University, Hiroshima 739-8529, Japan. phungtuyen@gmail.com.
authors.forename: Phung Thi
authors.initials: PT
authors.lastname: Tuyen
authors.affiliation: Graduate School for International Development and Cooperation, Hiroshima University, Hiroshima 739-8529, Japan. ltminh87@gmail.com.
authors.forename: Luong The
authors.initials: LT
authors.lastname: Minh
authors.affiliation: Graduate School for International Development and Cooperation, Hiroshima University, Hiroshima 739-8529, Japan. hoanganh6920@gmail.com.
authors.forename: La Hoang
authors.initials: LH
authors.lastname: Anh
authors.affiliation: Graduate School for International Development and Cooperation, Hiroshima University, Hiroshima 739-8529, Japan. nguyenquan26@gmail.com.
authors.forename: Nguyen Van
authors.initials: NV
authors.lastname: Quan
authors.affiliation: Graduate School for International Development and Cooperation, Hiroshima University, Hiroshima 739-8529, Japan. phamthithuhabt@gmail.com.
authors.forename: Pham Thi Thu
authors.initials: PT
authors.lastname: Ha
authors.affiliation: Graduate School for International Development and Cooperation, Hiroshima University, Hiroshima 739-8529, Japan. quanagi@gmail.com.
authors.forename: Nguyen Thanh
authors.initials: NT
authors.lastname: Quan
authors.affiliation: Graduate School for International Development and Cooperation, Hiroshima University, Hiroshima 739-8529, Japan. nguyenphutoan1983@gmail.com.
authors.forename: Nguyen Phu
authors.initials: NP
authors.lastname: Toan
authors.affiliation: Department of Agricultural Botany, Faculty of Agriculture, Tanta University, Tanta 31527, Egypt. elzaawely@agr.tanta.edu.eg.
authors.forename: Abdelnaser Abdelghany
authors.initials: AA
authors.lastname: Elzaawely
authors.affiliation: Graduate School for International Development and Cooperation, Hiroshima University, Hiroshima 739-8529, Japan. tdxuan@hiroshima-u.ac.jp.
authors.forename: Tran Dang
authors.initials: TD
authors.lastname: Xuan
keywords: Phalaenopsis; antioxidant activity; moth orchids; phenolic compounds