Assessment of bioactive compounds and synergistic efffects from Miliusa sessilis plant against anthracnose diseases on mango fruits (Mangifera indica L. 'Nam Dok Mai Si Thong')

Three bioactive neolignans: dehydrodieugenol A (dA), dehydrodieugenol B (dB), and miliusin A (mA) were purified from Miliusa sessilis (MSE). The bioactive compounds (dA, dB, mA, dB-mA, mA-dA and dB-dA) at concentrations of 50, 100, 500, 1000, 2000, 3000, 4000 and 5000 ppm were carried out to determine antifungal activity for controlling Colletotrichum sp. The result showed that dB-dA at 5000 ppm inhibited mycelium growth by 43.46%, while dA and dB had a high fungal inhibition effect of 43.46% and 45.50%, respectively. However, there was no significant difference in these compounds (p<0.01). Furthermore, the potential antifungal activity using poison food technique revealed the greatest percentage inhibition in significant difference (p<0.01) compared to control and all treatments at 1000 ppm of mA, dA and dB-dA as 76.07%, 75.38% and 74.79%, respectively. The MIC values of dA, dB-mA, mA-dA and dB-dA were 6.25 ppm exceptionally; dB and mA had higher MIC values (12.5 ppm). In vivo antifungal activity evaluation, MSE had efficacy to suppress and reduce lesions on mango fruits. These findings supported that the synergism of MSE and showed strong antifungal effects and could be developed as an alternative to synthetic fungicides.