Changes in the Leaf Physiological Characteristics and Tissue-Specific Distribution of Ginsenosides in Panax ginseng During Flowering Stage Under Cold Stress

Abstract

Panax ginseng is a valuable traditional herbal medicine material with numerous applications. Ginsenosides are the key bioactive compounds in ginseng. Cold stress can activate stress tolerance mechanisms that regulate biomass and biosynthesis in ginseng tissue. In this study, the effects of short- and long-term cold stress (5°C) on the physiological characteristics, tissue-specific ginsenoside distributions, and ginsenoside synthesis gene expressions of 3-year-old P. ginseng during the flowering period were investigated. Short-term cold stress significantly reduced ginseng biomass (root fresh weight and dry weight), and increased malondialdehyde, proline, soluble sugar, and soluble protein concentrations. Superoxide dismutase, peroxidase, and catalase activities also increased significantly under cold stress. With prolongation of the cold stress period, all antioxidant enzyme activity decreased. The protopanaxatriol-type ginsenoside concentrations in the taproots (phloem and xylem) and fibrous roots, as well as the protopanaxadiol-type ginsenoside concentrations in the leaves, increased significantly under short-term cold stress. The key genes (SE, DS-II, CYP716A52v2, and CYP716A53v2) involved in the ginsenoside biosynthesis pathway were significantly positively correlated with the ginsenoside accumulation trends. Thus, short-term cold stress can stimulate membrane lipid peroxidation, in turn stimulating the antioxidant enzyme system to alleviate oxidative damage and increasing the expression of key enzyme genes involved in ginsenoside biosynthesis. During agricultural production, protopanaxadiol/protopanaxatriol ratios could be manipulated by low-temperature storage or treatments.

Molecular Regulatory Mechanism of Exogenous Hydrogen Sulfide in Alleviating Low-Temperature Stress in Pepper Seedlings

“…Impaired photosynthesis leads to an imbalance in light-dark reactions, and the electrons released by the photosynthetic electron transport chain are received by oxygen to form O 2 − [6]. At the same time, along with the lipid peroxidation of cell membranes, electrolyte leakage, the decrease in conductivity, the damage of the enzymatic oxidation system and ASA-GSH cycle, and MDA and ROS are also important indicators of lipid peroxidation of cell membranes and the first line of defense against low-temperature stress in plants [30]. In this study, after low-temperature stress, the pepper leaves rapidly curled and wilted (Figure 1A); with accelerated membrane lipid peroxidation (increased REC and MDA contents), the osmotic substance (Pro) content decreased, there was excessive accumulation of ROS (H 2 O 2 and O 2…”

In Vitro Cultivation and Ginsenosides Accumulation in Panax ginseng: A Review

“…cessfully from P. ginseng [31]. Therefore, this review summarizes the in vitro tissue culture methods on P. ginseng, which include direct root and shoot induction organogenesis without the formation of callus and indirect organogenesis from callus for further embryogenesis.…”

NO and GSH Alleviate the Inhibition of Low-Temperature Stress on Cowpea Seedlings

“…MDA content can be a key indicator to measure the degree of membrane lipid peroxidation in plants. The higher the MDA content, the higher the degree of plasma membrane peroxidation, and the weaker the ability of plants to withstand low temperatures [ 7 ].…”