Ultraviolet-B mediated biochemical and metabolic responses of a medicinal plant Adhatoda vasica Nees. at different growth stages

• Published in: Journal of photochemistry and photobiology. B, Biology Vol. 216; p. 112142
• Main Authors: Pandey, Avantika, Jaiswal, Deepanshi, Agrawal, Shashi Bhushan
• Format: Journal Article
• Language: English
• Published: Switzerland Elsevier B.V 01.03.2021; Elsevier BV
• Subjects: Adhatoda vasica; Alkaloids; Antioxidants; Ascorbic acid; Chlorophyll; Crosstalk; Diterpenes; Exposure; Fatty acids; Herbal medicine; Hydrogen peroxide; Indigenous plants; Inflammation; Localization; Malondialdehyde; Medicinal plants; Metabolic profile; Metabolic response; Metabolism; Metabolites; Oxidative stress; Photosynthesis; Phytosterols; Reduction; Secondary metabolites; Sesquiterpenes; Superoxide; Tocopherols; Triterpenes; Ultraviolet radiation; UV-B; O2; O3; APX; SOD; MDA; H2O2; Antioxidants; UV-B; Adhatoda vasica; Secondary metabolites; Metabolic profile; ROS; CAT; POX; OH
• ISSN: 1011-1344; 1873-2682
• DOI: 10.1016/j.jphotobiol.2021.112142

In the present study, the effects of elevated UV-B (eUVB; ambient ± 7.2 kJ m−2 day−1) were evaluated on the biochemical and metabolic profile of Adhatoda vasica Nees. (an indigenous medicinal plant) at different growth stages. The results showed reduction in superoxide radical production rate, whereas increase in the content of hydrogen peroxide which was also substantiated by the histochemical localization. Malondialdehyde content, which is a measure of oxidative stress, did not show significant changes at any of the growth stages however photosynthetic rate and chlorophyll content showed reduction at all growth stages under eUV-B exposure. Increased activities of the enzymatic and non-enzymatic antioxidants were noticed except ascorbic acid, which was reduced under eUV-B exposure. The metabolic profile of A. vasica revealed 43 major compounds (assigned under different classes) at different growth stages. Triterpenes, phytosterols, unsaturated fatty acids, diterpenes, tocopherols, and alkaloids showed increment, whereas reduction in saturated fatty acids and sesquiterpenes were observed under eUV-B treatment. Vasicinone and vasicoline, the two important alkaloids of A. vasica, showed significant induction under eUV-B exposure as compared to control. Treatment of eUV-B leads to the synthesis of some new compounds, such as oridonin oxide (diterpene) and α-Bisabolol oxide-B (sesquiterpene), which possess potent anti-inflammatory and anticancerous activities. The study displayed that differential crosstalk between antioxidants and secondary metabolites at different growth stages, were responsible for providing protection to A. vasica against eUV-B induced oxidative stress and enhancing its medicinal properties. [Display omitted] •UV-B induced differential biochemical and metabolic responses in Adhatoda vasica.•Malondialdehyde content showed non-significant changes under UV-B exposure.•UV-B increased vasicinone, vasicoline and two anticancerous compounds.•Strong antioxidant defense system provides tolerance against UV-B stress.