Evaluation of the Antioxidant Activities of Ya-hom Intajak, a Thai Herbal Formulation, and its Component Plants

Purpose: To evaluate the antioxidant effect of 80 % ethanol extract and its n-hexane and dichloromethane fractions of Ya-hom Intajak, and its 47 medicinal plants components.Methods: The 80 % ethanol extract and its n-hexane and dichloromethane fractions were investigated on human low-density lipoprotein (LDL)  peroxidation by thiobarbituric acid reactive substances (TBARS) assay. Antioxidant effect was also determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity and ferric reducing antioxidant power (FRAP) assays.Results: The extract of Ya-hom Intajak exhibited moderate DPPH  scavenging activity with an IC50 value of 99.08 µg/ml and a FRAP value of 1.12 mmol FeSO4/g. Among the individual plants, Terminalia chebula Retz., Caesalpinia sappan L., Cinnamomum bejolghota (Buch.-Ham.) and Ci. verum J. Presl, showed strong antioxidant activities. T. chebula was the most potent plant in the DPPH assay while Ca. sappan had the highest FRAP value. Among the extracts, the dichloromethane fraction showed the highest inhibitory effect on LDL peroxidation with a half maximal inhibitory concentration (IC50) value comparable to that of probucol (0.82 µg/ml). Pearson correlation analysis revealed that total phenolic content (TPC) showed high positive correlations with FRAP (r = 0.908, p < 0.01) and DPPH activities (r= 0.648, p < 0.01).Conclusion: Ya-hom Intajak is a valuable source of natural antioxidants and has a potential application as a cardiovascular protective formulation.Keywords: Ya-hom Intajak, Antioxidant activity, Terminalia chebula Retz., Caesalpinia sappan L., Cinnamomum bejolghota (Buch.-Ham.), Ci. verum J. Presl , Phenolic conten

The Thai medicinal plant Gynura pseudochina var. hispida: chemical composition and in vitro NF-Kappa B inhibitory activity

Gynura pseudochina (L.) var. hispida Thv. (Asteraceae) has been used in traditional medicine in Thailand for the treatment of conditions associated with chronic and acute inflammation. In continuation of our search for bioactive natural products from Thai medicinal plants, G. pseudochina var. hispida showed potential in vitro NF-kappaB (Nuclear Factor kappa B) inhibitory activity and, therefore, was chosen for bio-assay-guided isolation of active compounds. Bioassay-guided fractionation of the methanol extract of the leaves of G. pseudochina var. hispida led to the isolation and identification, by spectroscopic and mass spectrometric methods, of four compounds previously not reported from this poorly studied species: Quercetin 3- rutinoside (1), 3,5-di-caffeoylquinic acid (2), 4,5-di-caffeoylquinic acid (3), and 5-monocaffeoylquinic acid (4). This paper discusses the current knowledge of these active components as NF-kappaB inhibitors, which lends some support to the use of this plant in traditional medicine. Potential risks associated with pyrrolizidine alkaloids will, however, have to be investigated further

Traditionally used Thai medicinal plants: in vitro anti-inflammatory, anticancer and antioxidant activities

AIMS OF THE STUDY: In order to assess traditional Thai claims about the therapeutic potential of medicinal plants and to select plants for future phytochemical research, nine plant species with anti-inflammatory uses were selected from Thai textbooks and assessed for their in vitro anti-inflammatory, antiproliferative and antioxidant activities. METHODS: Nuclear factor-kappaB (NF-kappaB) inhibitory effects in stably transfected HeLa cells were determined by luciferase assay, and effects on LPS-induced pro-inflammatory mediators prostaglandin E2 (PGE2), interleukin (IL)-6, IL-1beta, and tumour necrosis factor (TNF)alpha in primary monocytes were assessed by ELISA. Cytotoxic activities were examined against HeLa cells, human leukaemia CCRF-CEM cells and the multidrug-resistant CEM/ADR5000 subline using the MTT and XTT tests. However, a redox status has been linked with both inflammation and cancer, antioxidant effects were also assessed using the DPPH, lipid-peroxidation, and Folin-Ciocalteau methods. RESULTS: Among all the nine species, Gynura pseudochina var. hispida and Oroxylum indicum showed the most promising NF-kappaB inhibitory effects with the lowest IC(50) values (41.96 and 47.45 microg/ml, respectively). Muehlenbeckia platyclada did not inhibit the NF-kappaB activation but effectively inhibited the release of IL-6, IL-1beta and TNF-alpha with IC(50) values ranging between 0.28 and 8.67 microg/ml. Pouzolzia indica was the most cytotoxic against CCRF-CEM cells and the multidrug-resistant CEM/ADR5000 cells (9.75% and 10.48% viability, at 10 microg/ml, respectively). Rhinacanthus nasutus was the most potent cytotoxicity against HeLa cells (IC(50) 3.63 microg/ml) and showed specific cytotoxicity against the multidrug-resistant CEM/ADR5000 cells (18.72% viability at 10 microg/ml, p CONCLUSIONS: This study provides in vitro evidence for the use of the Thai plants, most importantly Gynura pseudochina var. hispida, Oroxylum indicum and Muehlenbeckia platyclada as Thai anti-inflammatory remedies and these plants are now a priority for further phytochemical research