The effects of LED Spectra on synthesis of antiparasitic bioactive compound in Eurycoma longifolia hairy root culture against Blastocystis Sp

Eurycoma longifolia (also known as Tongkat Ali) is one of the valuable medicinal plants frequently used as traditional medicine in Malaysia. Its alkaloids and quassinoids reportedly confers antiparasitic activities. The effect of different Light Emitting Diode (LED) spectra treatments on E. longifolia hairy root cultures (ELHRCs) on alkaloid synthesis remains unexplored and its consequent antiparasitic effect on Blastocystis sp., a common intestinal protozoan parasite, is still unknown. In this study, the ELHRCs were irradiated to white, blue, red, blue plus red (1:1) and mint green LED illumination in vitro. The variation of alkaloids was assessed by using High-Performance Liquid Chromatography (HPLC) and employed to quantify 9-hydroxycanthin-6-one and 9-methoxycanthin-6-one. Subsequently, antiparasitic effect on Blastocystis sp. was assessed in in vitro parasite culture and the minimum inhibitory concentration (MIC₉₀) was measured. Results showed the yields of high-value 9-hydroxycanthin-6-one in hairy roots increased by 1.17-fold, 2.74-fold, and 1.91-fold after 8, 10, and 12 weeks of culture under white, mint green, and blue lights relative to dark (control), respectively. In addition, 9-methoxycanthin-6-one yield in hairy roots increase by 1.07-fold and 1.34-fold after 8 and 12 weeks of culture under white light than in dark. Moreover, the ELHRCs crude extraction exhibited the highest anti-protozoal activity at 0.1 mg/ml against Blastocystis sp, ST3 compared to Metronidazole (MTZ). These results indicate that LED treatments alters alkaloid composition and are promising for obtaining higher yields of antiparasitic agents from the ELHRCs and thus can be considered a potential complementary and alternative antimicrobial agent.