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The present study was designed to assess the allelopathic potential of invasive weed Ageratina adenophora leaf extracts on seed germination and seedling development efficiency of native tree [viz. Quercus leucotrichophora A. Camus (Oak) and Pinus roxburghii Sarg. (Pine)] and crop [(Triticum aestivum L. (Wheat) and Lens culinaris Medik. (Lentil)] species of Kumaun Himalaya. Pot experiments were conducted in the glasshouse of the Botany Department, D.S.B. Campus, Kumaun University Nainital, following a Completely Randomized Block Design (CRBD) with three treatments (C 1 -25%, C 2 -50%, and C 3 -100% of aqueous leaf extract) and one control, each with five replicates. The experiment lasted one year for tree species and continued until the seed maturation phase for crop species. Parameters such as seed germination proportion, root and shoot measurements, biomass, and crop productivity traits were recorded accordingly. Our bioassay results indicated that the inhibitory effect of leaf extracts on the measured traits of the selected native species was proportional to the applied extract concentrations of A. adenophora. Overall, lentil among crops and oak among tree species exhibited more inhibition compared to wheat and pine, respectively. At the highest concentration, reductions of 44%, 34%, 36%, and 24% in biomass production capacity were recorded for wheat, lentil, pine, and oak, respectively, while wheat and lentil productivity decreased by up to 33% and 45%, respectively. These results suggest that water-soluble allelochemicals produced by A. adenophora may impede the establishment of selected crop and tree species in agroecosystems and forest ecosystems invaded by this weed species. However, further studies on the characterization of phytochemicals and their specific role in seed germination and growth are warranted. Furthermore, the allelopathic potential of A. adenophora can be explored for the preparation of biopesticides and nature-friendly option to improve soil health, crop productivity, and reduce environmental pollution and management of this invasive weed., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The brown seaweed Padina boergesenii was collected from Gulf of Mannar; Southeast Coast of India. Free radical scavenging activities of aqueous extract of P. boergesenii was assessed by using DPPH, FRAP, superoxide scavenging activity, nitricoxide scavenging activity, hydroxyl radical scavenging activity and total phenolic content. The aqueous extracts of P.boergesenii exhibited effective DPPH radical scavenging activity (75.92±0.3%), FRAP radical scavenging activity (0.45±0.01), superoxide radical scavenging activity (102.5±0.02%), nitricoxide radical scavenging activity (64.80±0.03%) and hydroxyl radical scavenging activity (71.23±0.3 %) at a concentration of 500 μg/ml. P. boergesenii was also found to have high levels of phenolic content (1.90 ± 0.65 GAE/g) depending on concentration. These various activities were compared with standard antioxidants. In the study the brown seaweed P. boergesenii aqueous extract was seen to be the most effective extracts in terms of antioxidant activity. [ABSTRACT FROM AUTHOR]

Ten medicinal plants, namely Commiphora wightii, Hibiscus cannabinus, Anethum gravelons, Emblica officinalis, Ficus religiosa, Ficus racemosa, Ficus benghalensis, Ficus tisela, Mentha arvensis and Mimusops elengi, were screened for potential antibacterial activity against medically important bacterial strains, namely Pseudomonas aeruginosa, Proteus mirabilis, Staphylococcus aureus, Bacillus cereus, Alcaligenes faecalis and Salmonella typhimurium. The antibacterial activity was determined in aqueous and ethanol extracts using both agar disc diffusion and agar well diffusion methods. The ethanol extracts were more potent than aqueous extracts of all the plants studied. Pseudomonas aeruginosa and Salmonella typhimurium were the most resistant strains while the most susceptible bacterial strains were Bacillus cereus and Proteus mirabilis. Emblica officinalis showed strong activity against all the tested bacterial strains. Hence, this plant can be used to discover bioactive natural products that may serve as leads in the development of new pharmaceuticals that address unmet therapeutic needs. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To evaluate the antibacterial activity of Gracilaria verrucosa (G. verrucosa)(Hudson), Hypnea musciformis (H. musciformis)(Wulf) Lamour, Enatiocladia prolifera (E. prolifera)(Grev.) falk, Gracilaria ferugosoni (G. ferugosoni), Gelidium species and G. verrucosa var. against the selected bacterial pathogens. Methods: The antibacterial activities of methanol and aqueous hot extracts were tested against various organisms by using disc diffusion method. Results: The highest antibacterial activity (13 mm) was shown by the aqueous extract of G. verrucosa var. againstPseudomonas aeruginosa (P. aeruginosa) and the lowest activity (6 mm) was observed in the methanol extract ofE. prolifera againstEscherichia coli (E. coli). However in most of the seaweeds, methanol extract was found to be more effective. The microbial strainsSalmonella typhi (S. typhi), Staphylococcus aureus (S. aureus),Bacillus subtilis (B. subtilis) and Candida albicans (C. albicans)were resistant to the aqueous extracts of all seaweeds. Conclusion: Further work is needed to identify the principle compound which is responsible for antibacterial activity against pathogenic bacteria especially those causing the human diseases. [Copyright &y& Elsevier]

Ethnopharmacological Relevance: Different parts of Indian ethnomedicinal plant Shorea robusta is traditionally used for several ailments including wounds and burn by different tribal groups, since ages. Here we have validated, for the first time, the effectiveness and the possible mechanism of action of young leaf extracts of Shorea robusta, used by two distinct tribes of India, and its isolated compounds as a topical formulation in three wound models in rats., Materials and Methods: Bioactivity-guided study of the active extract resulted in the isolation of two known compounds. The prepared ointment containing extracts (2.5 and 5%, w/w), fractions (5% w/w) and isolated compounds (0.25% w/w) were evaluated on excision, incision and dead space wound models in rats by the rate of wound closure, period of epithelialisation, tensile strength, granulation tissue weight, hydroxyproline content and histopathology., Results: The animals treated with the extracts and fractions (5%) showed significant reduction in wound area 96.55 and 96.41% with faster epithelialisation (17.50 and 17.86), while the isolated compounds bergenin and ursolic acid heal the wound faster, but complete epithelialisation with 100% wound contraction was evident with 5% povidone-iodine group on 18th post-wounding day. Moreover, the tensile strength of incision wound, granuloma tissue weight, and hydroxyproline content was significantly increased in both the extract and compound(s) treated animals. Furthermore, the tissue histology of animals treated with the isolated compound(s) showed complete epithelialisation with increased collagenation, similar to povidone-iodine group., Conclusion: Thus, our results validated the traditional use of Shorea robusta young leaves in wound management., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)