In vitro inhibitory effects on free radicals, pigmentation, and skin cancer cell proliferation from Dendrobium hybrid extract: A new plant source of active compounds

Napachanok Mongkoldhumrongkul Swainson; Thanyawan Pengoan; Rungpailin Khonsap; Pilairath Meksangsee; Gerhard Hagn; Christopher Gerner; Attawan Aramrak

doi:10.1016/j.heliyon.2023.e20197

In vitro inhibitory effects on free radicals, pigmentation, and skin cancer cell proliferation from Dendrobium hybrid extract: A new plant source of active compounds

Heliyon. 2023 Sep 14;9(9):e20197. doi: 10.1016/j.heliyon.2023.e20197. eCollection 2023 Sep.

Authors

Napachanok Mongkoldhumrongkul Swainson¹, Thanyawan Pengoan¹, Rungpailin Khonsap¹, Pilairath Meksangsee¹, Gerhard Hagn², Christopher Gerner², Attawan Aramrak¹

Affiliations

¹ Department of Biochemistry, Faculty of Science, Kasetsart University, Thailand.
² Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Austria.

Abstract

Orchidaceae are diverse plants whose bioactive compounds have various biological activities. New hybrids of Dendrobium have been generated to gain characteristics shared with their ancestors. Dendrobium Pearl Vera (designated as DH) is derived from parents used for dermatological treatments and cosmetics. However, the phytoconstituents and biological properties of DH have not been reported. The current study investigated extracts from DH plants using four solvents (water, methanol, ethanol, or 2-propanol). The propanolic extract (DH-P) contained the highest phenolic and flavonoid contents, along with a high scavenging performance for free radicals. In total, 25 tentative constituents in the DH-P matrix were identified, consisting of amino acids, nucleotides, and three types of secondary metabolites: furan, phenolics, and alkaloids. The DH-P inhibited human tyrosinase in vitro in a concentration-dependent manner of the phenolic content. Furthermore, there was no significant difference between DH-P with 10 μg/ml phenolic content and 0.75 mM kojic acid (a commercial whitening agent) on the inhibition of human tyrosinase. Incubation with DH-P containing at least 15 μg/ml phenolic content greatly inhibited the proliferation of human melanoma; however, the cell viability was not affected by the phenolic content at 5 μg/ml or less. The half-maximal inhibitory concentration (IC₅₀) of the phenolic content in DH-P on melanoma viability was 12.90 ± 1.04 μg/ml. Melanin production in vivo by human melanoma incubated with 5 μg/ml phenolic content in DH-P was reduced significantly, compared to 2.5 μg/ml phenolic content in DH-P, 100 μg/ml arbutin, and in control. The identified components, including 5-hydroxymethyl-2-furaldehyde, salicylic acid, nicotinamide, acetophenone, cytidine, adenosine, proline, or valine, have been reported to be associated with depigmentation, antioxidant, and anticancer. This research revealed, for the first time, the tentative phytoconstituents of Dendrobium Pearl Vera and their biological activities, thus demonstrating the potential use of DH-P in dermal applications.

Keywords: Anticancer; Antioxidant; Mass spectrometry; Orchid; Phytochemicals; Whitening.