UTILIZATION OF PLANT WASTE FROM THE PHALAENOPSIS ORCHID HYBRIDS AS AN ANTIOXIDANT ANTIGOUT SOURCE

Abstract

Phalaenopsis spp. is commercially and economically important orchid, but its plant parts are often
unused, which has caused environmental problems. After flowering, parts of the plant are usually
discarded, resulting in environmental issues. Extracts of 20 industrial phalaenopsis orchids
(Phalaenopsis orchid hybrids) roots were evaluated for total phenols, total flavonoids, antioxidant
activity and ability to inhibit gout-causing enzyme - Xanthine oxidase (XO). The ethyl acetate (EtOAc)
extracts from the root of the "Flamingo" plant had the highest total phenolic (6.78 mg gallic acid/ dry
weight) and total flavonoid (4.93 mg rutin/ dry weight) content. The EtOAc extract from the root of the
"Catalina" plant showed the highest antioxidant and antihyperuricemia activities, compared with other
extracts. The IC50 of 1,1-diphenyl-picryl-hydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzothiazoline-6-
sulfonic acid) (ABTS), and energy-dispersive method experiments were 116.03 µg/mL, 145.39 µg/mL
and 128.61 mg/mL, respectively. The lipid peroxidation inhibition (LPI) of β-carotene bleaching
method was 74.3%. The Xanthine oxidase (XO) inhibition activity in the blood with an IC50 of 232.62
µg/mL was observed which was comparable to that of allopurinol standard. The results of the study
suggest that the industrial orchid hybrid root extracts could be used as natural antioxidants and as
adjuvant therapy for gout. This preliminary study investigated the agricultural waste, particularly the
root of the 'Flamingo' and 'Catalina' orchid hybrids for their diverse antioxidant properties and
warrants further investigation.