The Effect of Polyphenols Isolated from Cynanchi wilfordii Radix with Anti-inflammatory, Antioxidant, and Anti-bacterial Activity

Proliferation and Metabolic Profiling of Cynanchum wilfordii Adventitious Roots Using Explants from Different Cultivation Methods

Cynanchum wilfordii root is used in traditional herbal medicine owing to its various pharmacological activities. However, C. wilfordii roots are misused owing to their morphological similarities with C. auriculatum. Adventitious root (AR) culture can prevent such misuse, and the selection of plant materials is an important procedure for producing high-quality ARs. This study aimed to compare the proliferation and metabolic profiles of C. wilfordii ARs in two types of explants from different cultivation methods (either cultivated in open field (ECF) or cultivated on a heap of C. wilfordii (ECH)). After 4 weeks of culture, the proliferation rate and number and length of secondary ARs were determined, and 3/4 Murashige and Skoog (MS) salt medium, 4.92 μM indole-3-butyric acid (IBA), and 5% sucrose were suggested as the best proliferation conditions for ARs originating from both ECF and ECH. Through metabolic profiling, ARs from ECH were found to show higher accumulation patterns for flavonoids, polysaccharides, hydroxyacetophenones, aromatic amino acids, and mono-unsaturated fatty acids, which were ascribed to the activation of flavonoid biosynthesis, the phenylpropanoid pathway, and fatty acid desaturase, stimulated by abiotic stresses. In contrast, ARs from ECF had higher levels of TCA cycle intermediates, amino acids in the aspartate-glutamate pathway, and saturated and polyunsaturated fatty acids, indicating energy metabolism and plant development. Overall, the current study provided information on the optimal conditions for inducing C. wilfordii ARs with higher amounts of bioactive compounds.

Acute and 13-week subchronic toxicity studies of hot-water extract of Cynanchi wilfordii Radix in Sprague-Dawley rats

Cynanchi wilfordii Radix (CWR) is a herbal medicinal plant that is well-known and used in Asian countries as a health food. In this study, acute and 13-week subchronic oral toxicity studies of hot-water extract of CWR (CWR-WE) were performed in Sprague-Dawley rats. For the acute toxicity study, CWR-WE was administered once orally to five male and five female rats at doses of 800, 2000, and 5000 mg/kg. Mortality, clinical signs, and body weight changes were monitored over 14 days. There were no treatment-related changes in these parameters and the approximate lethal dose of CWR-WE in male and female rats was determined to be > 5000 mg/kg. For the subchronic toxicity study, CWR-WE was administered orally once daily to male and female rats for 13 consecutive weeks at doses of 0 (vehicle control), 500, 1000, and 2000 mg/kg/day (n = 10 rats/sex/group). There were no toxicologically significant changes with regard to clinical signs, body weight, food consumption, ophthalmology, urinalysis, hematology, clinical chemistry, organ weights, necropsy findings, and histopathological findings. These results suggest that the oral no observed adverse-effect level of CWR-WE is > 2000 mg/kg/day for both sexes, although target organs were not identified.