Objectives: Dichapetalum gelonioides (Roxb.) Engl. belongs to the family Dichapetalaceae. In the present study, we investigated antibacterial, antifungal and antioxidant activity of methanolic extract of leaf and fruit of D. gelonioides. Methods: Maceration process was carried out for extraction of leaf and fruit of D. gelonioides. Agar well diffusion method was employed to evaluate antibacterial activity of extracts against gram positive and gram negative bacteria. Poisoned food technique was performed to investigate antifungal activity of extracts against two seed-borne fungi. Antioxidant activity was evaluated by DPPH radical scavenging and ferric reducing assays. Results: Both leaf and fruit extracts were effective in causing inhibition of all test bacteria. Highest and least inhibitory activity was observed against Bacillus cereus and Escherichia coli respectively. Both Aspergillus niger and Bipolaris sp. were inhibited to >50% by leaf and fruit extracts. Extent of inhibition of Bipolaris sp. was slightly higher when compared to A. niger. Both leaf and fruit extracts showed a dose dependent scavenging of DPPH radicals with high activity being showed by leaf extract. Leaf extract was shown to exhibit marked reducing potential than fruit extract. Conclusions: Overall, leaf extract was shown to be more effective in displaying antioxidant activity and causing inhibition of bacteria and fungi when compared to fruit extract. The results indicate that the plant possess active principles which are to be purified, characterized and subjected for antimicrobial and antioxidant assays in further studies.

Objectives: Argyreia cuneata (Willd.) Ker Gawl. belongs to the family Convolvulaceae. The present study was performed to screen the potential of crude extract of various parts of A. cuneata to exhibit antimicrobial activity. Methods: Extraction of shade dried and powdered leaf, stem and flower of A. cuneata was carried out by maceration technique. Antibacterial and antifungal activity of extracts was evaluated by Agar well diffusion and Poisoned food technique respectively. Antioxidant activity was determined by DPPH radical scavenging, ABTS radical scavenging and ferric reducing assays. Results:  All extracts were effective in inhibiting test bacteria and the susceptibility of bacteria to extracts was in the order: Bacillus cereus > Shigella flexneri > Escherichia coli > Salmonella typhimurium. Leaf extract and stem extract exhibited highest and least antibacterial activity, respectively. Extracts were effective in causing inhibition of seed-borne fungi viz. Aspergillus niger and Bipolaris sp to >50%. Leaf extract exhibited marked antifungal activity followed by flower extract and stem extract. All extracts were shown to exhibit concentration dependent scavenging and reducing activity. Antioxidant activity of extracts observed was in the order: leaf extract > flower extract > stem extract.  Conclusion: Among various parts of A. cuneata, leaf extract exhibited marked antimicrobial and antioxidant activity. The plant can be employed as an effective antimicrobial and antioxidant agent in suitable form. Further studies may be undertaken to recover phytochemicals from the plant and to investigate the antimicrobial and antioxidant activity of isolated components. Keywords: Argyreia cuneata, Maceration, Antimicrobial, Agar well diffusion, Poisoned food technique, Antioxidant

Objectives: Lophopetalum wightianum Arn. (Celastraceae) is a lofty evergreen tree reaching around 40m in height. The present study was carried out to investigate antimicrobial and antioxidant activity of leaf and bark extract of L. wightianum. Methods: The shade dried and powdered leaf and bark were extracted by maceration process using methanol. Extracts were screened for phytoconstituents present by standard protocols. Antibacterial and antifungal activity of extracts was evaluated by agar well diffusion and poisoned food technique respectively. Antioxidant activity was determined by DPPH radical scavenging and ferric reducing assays. Results: Phytochemicals viz. alkaloids, flavonoids, sterols, saponins and triterpenoids were detected in both leaf and bark extracts. Inhibitory activity against test bacteria of bark extract was marked than leaf extract. Bark extract displayed more or less similar activity against test bacteria with slightly higher activity against Salmonella typhimurium and Shigella flexneri. Leaf extract was more effective against Bacillus cereus while other bacteria were inhibited to more or less similar extent. In antifungal activity, leaf extract showed highest inhibitory against Bipolaris sp. than A. niger. Bark extract showed more or less similar antifungal activity against A. niger and Bipolaris sp. Bark extract scavenged DPPH radicals more efficiently with IC 50 value 7.03µg/ml than leaf extract which scavenged radicals with IC 50 value of 24.64µg/ml. Reducing potential exhibited by bark extract was higher when compared to leaf extract. Conclusion: Overall, bark extract displayed marked antimicrobial and antioxidant potential. The plant is shown to contain bioactive principles with activity against pathogenic microorganisms and free radicals that cause oxidative damage.