Article InformationThe members of the genus Ramalina (Ramalinaceae) are fruticose lichens growing on various types of substrata. The present study was conducted with an aim of determining antimicrobial activity of Ramalina conduplicans Vain. The powdered lichen material was extracted sequentially using petroleum ether, ethyl acetate and ethanol. The solvent extracts were screened for antibacterial activity by Agar well diffusion assay against 15 bacteria which included reference strains and isolates from burn, dental caries and urinary tract infections. Poisoned food technique was performed to determine antifungal effect of solvent extracts against fungal isolates from anthracnose of chilli, foot rot of finger millet and mouldy grains of sorghum. Usnic acid, Salazinic acid and Sekikaic acid were detected in the lichen. The solvent extracts were shown to exhibit dose dependent inhibitory activity against test bacteria. Ethyl acetate extract inhibited reference bacterial strains to higher extent. Among solvent extracts, only ethanol extract inhibited all urinary tract bacteria. S. aureus isolates from burn were inhibited to higher extent when compared to S. mutans isolates from dental caries. The solvent extracts exhibited varied inhibitory activity against test fungi. Ethyl acetate extract inhibited Alternaria sp., Aspergillus flavus and Sclerotium rolfsii to higher extent while Colletotrichum capsici and Helminthosporium sp. were inhibited to higher extent by petroleum ether and ethanol extract respectively. The observed inhibitory potential of solvent extracts of R. conduplicans could be ascribed to the presence of secondary metabolites. The lichen can be used in the treatment of bacterial infections and to manage plant pathogenic fungi.

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.

Article Information The present study was carried out to investigate the analgesic activity of leaf extract of Olea dioica (Roxb) belonging to the family Oleaceae. Acute toxicity was determined by administering single oral dose of 2000mg/kg b.w to Swiss albino mice. The results showed no toxicity in terms of general behavior change and mortality and LD50 was found to be more than 2,000 mg/kg. Analgesic effect of extract was evaluated in Swiss Albino mice by Tail flick method. The animals were administered with 100, 200 and 300 mg extract/kg b.w and the positive control used for the study was Pentazocine (5mg/kg). The extract and Pentazocine showed significant analgesic activity as compared to control. The extract increased pain threshold indicating that the extract exhibit analgesic activity.

Objectives: The present study was conducted to investigate the potential of leaf extract of Geophila repens (L.) I.M. Johnst. (Rubiaceae) to exhibit antioxidant and antifungal potential. Methods: Extraction of powdered leaf material was carried out by maceration process using methanol. Antioxidant activity of leaf extract was assessed by DPPH free radical scavenging assay and ferric reducing assay. Antifungal activity of leaf extract was determined by Poisoned food technique. Results: Leaf extract was shown to scavenge DPPH radicals dose dependently with IC50 value of 51.39µg/ml. An increase in the absorbance on increasing concentration of leaf extract indicated ferric reducing activity. The extract showed more or less similar inhibitory activity against Aspergillus niger and Bipolaris sp. (>50% inhibition). Conclusion: The results of the study indicate that leaf extract possesses bioactive principles with activity against oxidative damage and seed-borne fungi which are to be purified and screened for antioxidant and antifungal activity. Keywords: Geophila repens, Maceration, DPPH, Ferric reducing, Seed-borne fungi, Poisoned food technique

Western Ghats of India represents one of the global biodiversity hotspots. The present study was carried out to isolate and determine antimicrobial, cytotoxic and antioxidant activity of actinomycetes from soils of different regions of Western Ghats of Shi Karnataka, India. A total of 182 isolates were recovered from 57 soil samples collected at 13 different regions of Western Ghat region of Shivamogga district by serial dilution technique. Out of 182 isolates, 17 isolates were chos determine antimicrobial, cytotoxic and antioxidant activity. Solvent extracts of these isolates exhibited varied antimicrobial potency against Gram positive and Gram negative bacteria, yeasts and molds. Ethyl acetate was found to be best solvent for extraction of bioactive metabolites from most of isolates followed by butanol and hexane. Cytotoxic activity, as evaluated by brine shrimp lethality bioassay, revealed the potency of extracts to cause dose dependent mortality of brine shrimp larvae. Solvent extracts exhibited dose dependent antioxidant activity, as evaluated by DPPH, ABTS, Metal chelating and Ferric reducing assays. Western Ghat actinomycetes appear to be promising resources of bioactive agents and can be exploited industrially. Further studies on recovery of active constituents from solvent extracts and their bioactivity determinations are to be carried out. Abstract Article InformationWestern Ghats of India represents one of the global biodiversity hotspots. The present study was carried out to isolate and determine antimicrobial, cytotoxic and antioxidant activity of actinomycetes from soils of different regions of Western Ghats of Shivamogga district, Karnataka, India. A total of 182 isolates were recovered from 57 soil samples collected at 13 different regions of Western Ghat region of Shivamogga district by serial dilution-plating technique. Out of 182 isolates, 17 isolates were chosen for solvent extraction and to determine antimicrobial, cytotoxic and antioxidant activity. Solvent extracts of these isolates exhibited varied antimicrobial potency against Gram positive and Gram negative bacteria, und to be best solvent for extraction of bioactive metabolites from most of isolates followed by butanol and hexane. Cytotoxic activity, as evaluated by brine shrimp lethality bioassay, revealed the potency of extracts to cause dose brine shrimp larvae. Solvent extracts exhibited dose dependent antioxidant activity, as evaluated by DPPH, ABTS, Metal chelating and Ferric reducing assays. Western Ghat actinomycetes appear to be promising resources of bioactive agents ed industrially. Further studies on recovery of active constituents from solvent extracts and their bioactivity determinations are to be carried out.