Abstract
A split plot 3 by 4 experiment was designed to investigate and distinguish the relationships among production of secondary metabolites, soluble sugar, phenylalanine ammonia lyase (PAL; EC 4.3.1.5) activity, leaf gas exchange, chlorophyll content, antioxidant activity (DPPH), and lipid peroxidation under three levels of CO2 (400, 800, and 1200 μmol/mol) and four levels of light intensity (225, 500, 625, and 900 μmol/m2/s) over 15 weeks in Labisia pumila. The production of plant secondary metabolites, sugar, chlorophyll content, antioxidant activity, and malondialdehyde content was influenced by the interactions between CO2 and irradiance. The highest accumulation of secondary metabolites, sugar, maliondialdehyde, and DPPH activity was observed under CO2 at 1200 μmol/mol + light intensity at 225 μmol/m2/s. Meanwhile, at 400 μmol/mol CO2 + 900 μmol/m2/s light intensity the production of chlorophyll and maliondialdehyde content was the highest. As CO2 levels increased from 400 to 1200 μmol/mol the photosynthesis, stomatal conductance, f v/f m (maximum efficiency of photosystem II), and PAL activity were enhanced. The production of secondary metabolites displayed a significant negative relationship with maliondialdehyde indicating lowered oxidative stress under high CO2 and low irradiance improved the production of plant secondary metabolites that simultaneously enhanced the antioxidant activity (DPPH), thus improving the medicinal value of Labisia pumila under this condition.
Highlights
Labisia pumila, locally known as Kacip Fatimah, is a herbaceous plant belonging to the family Myrsinaceae
The present results indicate that enrichment of L. pumila with high CO2 (1200 μmol/mol) with 225 μmol/m2/s irradiance can upregulate the production of total phenolics and flavonoids in the plant
The increased production of secondary metabolites under high CO2 and low irradiance is attributed to the enhanced availability of soluble carbohydrates under this condition that upregulates the production of total phenolics and flavonoids [58]
Summary
Locally known as Kacip Fatimah, is a herbaceous plant belonging to the family Myrsinaceae. It is widely scattered in the lowland and hilly rain forests of Malaysia, Thailand, Indochina, The Philippines, and New Guinea [1,2,3]. Three varieties of L. pumila are identified in Malaysia, classified as L. pumila var. It is usually used as a tonic drink among females, and its indication for women’s health may be related to its phytoestrogen effects and having similar chemical structure to estrogen [4]. The varieties most universally utilized by the traditional healers are L. pumila var. The other uses of this herb include treatments for dysentery, dysmenorrheal, flatulence, and gonorrhea [7,8,9,10]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
