RESEARCH ON PRODUCTION AND EVALUATION OF SOME BIOLOGICAL ACTIVITIES OF Anoectochilus roxburghii IN VITRO CULTURE

Abstract

Anoectochilus roxburghii (Wall) L. is a valuable medicine herb and some functional foods. However, A. roxburghii in the wild has become endangered, and cultivation in nurseries results in low yields. Therefore, to provide A. roxburghii biomass as an alternative plant material, this study focused on the effects of monochromatic light (Light Emitting Diode - LED) on plant growth and the proliferation of biomass in the bioreactor system. At the same time, the study also initially evaluated some biological activities of in vitro cultured plant biomass. The results showed that the growth criteria for A. roxburghii shoots placed under 70% red LED combined with 30% blue LED were better than under other lighting conditions. In bioreactor systems (a bioreactor tank with a volume of 2 liters containing 1 liter of medium), the treatment using 20 g fresh weight of initial material was found appropriate and effective for biomass production of A. roxburghii. The proliferation coefficient achieved was 2.7 times after 4 weeks of culture in this bioreactor system. To evaluate the quality of A. roxburghii biomass, qualitative and quantitative tests of some secondary compounds were also performed. The results indicated the presence of flavonoid, phenolic, tannin, saponin, carbohydrate, and phytosterol in the A. roxburghii extract. The total phenolic content of A. roxburghii biomass was 8.82 mg GAE/g DW, and the DPPH antioxidant activity of the extract was 203.44 µg/mL. Among the four bacterial strains in the ESKAPE group surveyed, the A. roxburghii extract was resistant to two strains: S. aureus and E. agglomerans. These results show that in vitro cultured A. roxburghii biomass can be considered a potential medicinal source to supplement the scarce natural A. roxburghii supply.