Background: Lactic acid bacteria are regarded the most important bacteria concerning food fermentation, pharmaceutical and special dietary applications. Strains have been isolated from environments rich in available carbohydrate substrates, such as food and feed, but also in human and animal cavities and in sewage and plant material. Besides lactic acid, other side products include acetate, ethanol, CO2, formate and succinate. The most important advantage of Lactic acid bacteria making them suitable for the use in food biotechnology, is that they are generally recognized as safe (GRAS). Studies on Lactic acid bacteria isolated from aerial parts of plants are scarce. Bacteria that colonize plant roots and promote plant growth are referred to as plant growth-promoting rhizobacteria. Several substances produced by antagonistic rhizobacteria have been related to pathogen control and indirect promotion of growth in many plants. The present work explores the potential use of Lactic acid bacteria in promotion of plant growth. Methods: Three isolates were obtained from aerial parts of pomegranate plant and confirmed by 16S rRNA sequencing to belong to Leuconostoc sp. The isolates were checked for plant growth promoting traits viz. antifungal activity, production of plant growth hormones, enzymes and 1-amino cyclopropane carboxylate deaminase activity. Result: As LAB showed plant growth promoting traits, they can be suitably used for plant growth promotion.

Researchers around the world have experienced the dual nature of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), ‘tragically lethal in some persons and surprisingly benign in others’. They have congregated to study novel coronavirus disease (COVID-19), a disease that mainly attacks the lungs, but also has mystifying effects on the heart, kidneys and brain. Researchers are also gathering information to determine what actually kills COVID-19 patients, whether respiratory disorder or coagulation disorder or multi organ failure. Various laboratory parameters like lactate, ferritin, hypoalbuminemia have been established as risk factor or associated with poor outcomes, but yet could not be substantiated with the scientific biochemical rationale.  SARS-CoV-2 affects the alveolar type II epithelial cells, that significantly disturbs its surfactant homeostasis, deprive Na,K-ATPase of  ATP, thereby  disturbing the alveolar lining fluid which then gradually decreases the alveolar gaseous exchange  initiating intracellular hypoxic conditions. This activates AMP-activated kinase, which further inhibits Na,K-ATPase, that  can  progressively cause  respiratory distress syndrome. The virus may infect endothelial cell (EC), which being low energetic, cannot withstand the huge energy requirement towards viral replication,  and therefore glycolysis,  the prime energy generating pathway,  has to mandatorily be upregulated, which can be achieved by Hypoxia-inducible factor 1 (HIF-1). However, HIF-1 activates transcription of von Willebrand factor, plasminogen activator inhibitor-1, and suppresses the release of thrombomodulin, thereby setting off the coagulation cascade that leads to in-situ pulmonary thrombosis and micro clots. The proposed HIF-1 hypothesis can rationalize various features, clinical laboratory as well as autopsy findings such as respiratory distress syndrome, increased  blood ferritin and lactate levels, endothelial invasion, in-situ pulmonary thrombosis and micro clots,  and multiorgan failure in COVID -19 Keywords: novel coronavirus, COVID-19, SARS-CoV-2, severe acute respiratory syndrome coronavirus 2, hypoxia-inducible factor-1

Mouthwash is one of the most convenient and effective method employed for dental plaque management. The aim of the undertaken study was to establish the antimicrobial and anti-biofilm properties of lemongrass essential oil (LGEO) based mouthwash on microbial flora from dental plaque and also check cytotoxicity of mouthwash formulation. Five main colonizers of dental plaque representing dental microflora and three different bacterial species mainly responsible for the formation of biofilm were selected in this study. LGEO based mouthwash was developed and its stability was also determined. The antimicrobial and anti-biofilm activity of LGEO based mouthwash has been evaluated against the representative dental microflora as per CLSI guidelines. Cytotoxicity of mouthwash was checked by globally used MTT assay employing NIH 3T3 mouse fibroblast cell line. The mouthwash has been found to exhibit the stability in its major component, citral and also found exhibit antimicrobial and anti-biofilm activity against dental microflora. No cytotoxic effect was observed on mouse fibroblast cell line. LGEO in formulated mouthwash being a natural, herbal material isolated from traditional medicinal plants appears as a good and effective substitute to control the microflora linked with dental plaque.

Aims: Dental biofilms are complex, multi-species microorganism communities that inhabit the oral cavity in the form of dental plaque which causes dental caries and periodontal diseases. The present study aims to explore the potential of Lemon Grass Essential Oil (LGEO) extracted from Cymbopogon citratus as antimicrobial and antibiofilm agent against the microorganisms responsible for dental plaque. Study Design: Observational and comparison study. Place and Duration of Study: Research centre, Department of Microbiology, Abasaheb Garware college, Pune, India, between Dec 2012 to Jan 2017. Methodology: Three bacterial species primarily responsible for the biofilm formation were isolated from dental plaque and identified using 16S ribosomal RNA sequences. Five most primary colonizer of dental plaque organisms were acquired from the Microbial Type Culture Collection cultures. Antimicrobial as well as antibiofilm activity of LGEO, was determined against these eight biofilm forming microorganism. The antibiofilm activity of LGEO was evaluated against oral flora individually, as well as in consortium. Results: LGEO displayed excellent antimicrobial activity against eight test organisms associated with dental plaque, representing four genera namely Streptococcus, Staphylococcus, Lactobacillus and Candida. MIC of LGEO for all test organisms was determined as 1.5% (v/v). The LGEO was found to exhibit as high as 76% biofilm inhibitory activity even in the consortium, where the biofilm formation sometimes has been noted to be comparatively more than that of the individual organism, making LGEO a very promising antibiofilm agent. Conclusion: LGEO present in rampantly grown plant, Cymbopogon citratus, has remarkable antimicrobial and antibiofilm activity against the dental plaque organism and thus can be the economical, convenient, natural and nontoxic herbal material to effectively control the oral microflora associated with dental plaque.

Dental biofilms inhabit the oral cavity in form of dental plaque which then causes dental caries and periodontal diseases worldwide. Lemon grass essential oil (LGEO) has been reported to exhibit antimicrobial and antibiofilm activity against. This study represents the potential of citral and derivatives as antimicrobial and antibiofilm agent against dental microflora. Three bacterial species chiefly responsible for biofilm formation, and five prime colonizer of dental plaque were selected to represent dental microflora. Citral and its derivative viz. citral semicarbazone, exhibited antimicrobial and antibiofilm activity against the selected organisms. For the first time, any citral derivative has ever demonstrated to exhibit antimicrobial and antibiofilm activity against the oral microflora. However, study could not established citral or its derivatives as more effective, powerful and better herbal material as compared to LGEO to control the oral microflora associated with dental plaque.