Article Information Anthracnose is a serious disease of chilli which results in major crop loss. Species of Colletotrichum are the causative agents of chilli anthracnose. In the present study, we investigated the inhibitory effect of a total of 50 extracts from 35 plants (belonging to 23 botanical families) of Western Ghats of Shivamogga district, Karnataka, India. The powdered plant materials were extracted using methanol. The methanol extracts were screened for antifungal activity by Poisoned food technique against Colletotrichum capsici isolated from anthracnose of chilli. All extracts were effective in inhibiting the growth of C. capsici but to a varied extent (16 to 74% inhibition). The mycelial growth of fungus was found to be reduced on poisoned plates when compared to control plate. Marked inhibitory efficacy was observed in case of leaf extract of Maesa indica (74.19%) followed by leaf extract of Pimenta dioica (70.96%). Least inhibition of the fungus was shown by leaf extract of Persea macrantha (16.13%). The extent of inhibition of the fungus by other extracts ranged between 20 to 70%. In conclusion, the plants selected in this study appear promising as natural antifungal agents. Further field studies are to be conducted to determine the possible application of these plants in the control of chilli anthracnose.

Objective: The present study was designed to study phytochemicals and biological activities of the methanolic extracts of two traditional medicine plants Achyranthes aspera and Catharanthus roseus of Nepalese origin. Methods: Plant extracts were prepared by cold percolation method. Antioxidant activity, brine shrimp lethality assay, and analysis of phytochemical constituents were carried out using standard methods. The dinitro salicylic acid (DNS) method was used to study the inhibition effect of extracts on α-amylase enzyme. Furthermore, PTP 1B inhibitory activity was evaluated using p-nitrophenyl phosphate (p-NPP) as substrate. Results: Phytochemical analysis showed the presence of phytochemicals like alkaloids, flavonoids, glycosides, reducing sugars, etc. in both plants. Brine shrimp lethality assay suggested the presence of pharmacologically active compounds. Total phenolic content and total flavonoid content of C. roseus were found to be higher with 73.21 mg GAE/g and 33.15 mg Q/g respectively than that of A. aspera, which was found to be 57.09 mg GAE/g and 28.96 mg Q/g respectively. Similarly, the α-amylase inhibition of A. aspera and C. roseus was found to be 97.60±1.11 µg/ml and 94.05±1.18 µg/ml comparative with IC50 68.13±0.46 µg/ml of standard acarbose. Protein tyrosine phosphatase 1B (PTP1B) inhibition showed IC50 for A. aspera and C. roseus to be 48.72±0.46 and 50.21±1.03 µg/ml, respectively. Qualitative GC-MS analysis of both plant hexane fractions showed acid and ester type of phytoconstituents. Conclusion: These results suggested that both plants i. e A. aspera and C. roseus, Nepal origin showed biological activity by targeting multiple drug targets which justifies their traditional uses.

Article Information The present study was conducted to determine antimicrobial and radical scavenging potential of extract of two species of the genus Memecylon (Melastomataceae) viz., M. malabaricum (C.B. Clarke) Cogn. and M. talboltianum Brandis. The shade dried leaf materials of both Memecylon species were extracted using methanol. Antibacterial activity of leaf extracts was evaluated against five drug resistant uropathogenic bacteria by Agar well diffusion assay. Antifungal activity of leaf extracts was tested on the basis of mycelial growth inhibition of Colletotrichum capsici (isolated from anthracnose of chilli). Radical scavenging activity of extracts was determined by performing DPPH free radical scavenging activity. Total phenolic content of extracts was estimated by Folin-Ciocalteau reagent method. The extracts were subjected to preliminary phytochemical analysis to detect the presence of phytoconstituents. Among extracts, extract of M. malabaricum inhibited all test bacteria and inhibitory potential was marked against Gram positive bacteria than Gram negative bacteria. C. capsici was highly susceptible to extract of M. malabaricum when compared to extract of M. talboltianum. Overall, extract of M. malabaricum displayed marked antimicrobial activity than extract of M. talboltianum. Extract of M. malabaricum scavenged DPPH radicals more efficiently (IC50 6.26µg/ml) when compared to extract of M. talboltianum (IC50 43.80µg/ml). The content of total phenolics was also high in leaf extract of M. malabaricum (112µg GAE/mg) than that of M. talboltianum (28µg GAE/mg). Preliminary phytochemical analysis of leaf extracts revealed the presence of flavonoids, tannins, saponins and glycosides in both extracts. The antimicrobial and radical scavenging activity of leaf extracts could be ascribed to the presence of phytochemicals mainly phenolic compounds. These plants appear to be potential candidates for control of anthracnose disease of chilli and for development of agents active against drug resistant uropathogens and oxidative damage.