Evaluation of anti-inflammatory and wound healing potential of tannins isolated from leaf callus cultures of Achyranthes aspera and Ocimum basilicum.

Herbal medicines are important in treatment of inflammation as they are safe and nontoxic. Tannins are important bioactive compounds used as anti-inflammatory agents and possess wound healing potential. Anti-inflammatory activity of tannins extracted from seedling leaf tissue and callus culture extracts of Achyranthes aspera L. and Ocimum basilicum L. were determined using Carrageenan induced paw edema model. Wound healing potential of tannins from callus cultures of leaf explants of both plants were evaluated using four models in rabbits i.e. excision, incision, dead space and burn wound. Group I acted as control, Group II treated with Povidone iodine as standard drug. Groups III and IV were experimental groups treated with creams which consisted of tannins of callus cultures of leaf; cream A (A. aspera) and cream O (O. basilicum). The results of anti-inflammatory activity of callus cultures of leaf explants were comparable with standard drug Indomethacin. Seedling leaf tissue and callus culture extracts of A. aspera and O. basilicum plant showed decrease in paw edema thickness, size and maximum percentage inhibition of paw edema respectively. Among four wound models burn wound showed the best wound contraction by Cream O. Hydroxyproline content and tensile strength of dead space and incision wounds exhibited good result also respectively. Cream O exhibited best results as compared to cream A. Histopathological examination showed that cream O showed faster rate of fibroblast and collagen formation as compared to cream A. The results showed that condensed tannins of callus cultures of leaf of A. aspera exhibited the best anti-inflammatory activity while tannins from callus cultures O. basilicum showed the best results for wound healing. These findings may enable use of both plants for formulation of new phytomedicine.

Flagellar motility plays important role in Biofilm formation of Bacillus cereus and Yersinia enterocolitica.

Bacteria live either independently as planktonic cells or in organized surface associated colonies called as biofilms. Biofilms play an important role in increased pathogenesis of bacteria and it is assumed that motility is one of the contributing factors towards biofilm initiation. This study was planned to identify the role of flagella in biofilm formation by constructing flagellated (wild type) and physically disrupted variants (non-motile). Total 10 clinical bacterial strains were isolated and characterized. Morphological and biochemical study identified these strains as Enterobacter spp., Pseudomonas spp., Yersinia spp., Escherichia spp., Salmonella spp., Proteus spp., Staphylococcus spp., Streptococcus spp., Lactobacillus spp. and Bacillus spp. Among all strains, two strains including Yersinia spp and Bacillus spp. showed higher antibiotic resistance, hence studied at molecular and physiological level. Biofilm formation capacity of strains was analyzed using three methods including Congo red assay, Test tube assay and Liquid-interface coverslip assay. Afterwards, flagellar disintegration was induced by blending and centrifugation for 5, 10 and 15 minutes. 16S rRNA sequencing showed two strains as Bacillus cereus and Yersinia enterocolitica. Both strains produced significant biofilm by all three above mentioned methods. A motility test of these blended variants showed partial/diminished motility with increased blending time. The significant loss in biofilm formation after 15 minutes blending confirmed the important flagellar contribution to the initiation of biofilm formation. This biofilm defect observed in flagella paralysed/minus variants presumably may be due to defects in attachments to surface at early stages. This study indicated that flagellar motility is crucial initially for surface attachment and subsequently for biofilm formation.

Risk assessment of Bt crops on the non-target plant-associated insects and soil organisms.

Transgenic plants containing Bacillus thuringiensis (Bt) genes are being cultivated worldwide to express toxic insecticidal proteins. However, the commercial utilisation of Bt crops greatly highlights biosafety issues worldwide. Therefore, assessing the risks caused by genetically modified crops prior to their commercial cultivation is a critical issue to be addressed. In agricultural biotechnology, the goal of safety assessment is not just to identify the safety of a genetically modified (GM) plant, rather to demonstrate its impact on the ecosystem. Various experimental studies have been made worldwide during the last 20 years to investigate the risks and fears associated with non-target organisms (NTOs). The NTOs include beneficial insects, natural pest controllers, rhizobacteria, growth promoting microbes, pollinators, soil dwellers, aquatic and terrestrial vertebrates, mammals and humans. To highlight all the possible risks associated with different GM events, information has been gathered from a total of 76 articles, regarding non-target plant and soil inhabiting organisms, and summarised in the form of the current review article. No significant harmful impact has been reported in any case study related to approved GM events, although critical risk assessments are still needed before commercialisation of these crops. © 2016 Society of Chemical Industry.