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Helicobacter pylori (H. pylori) infection is a global public health concern. Due to its high adaptability in various adverse environments (temperature, pH, adhesion, phenotypic forms), targeting the bacterium is quite challenging. Moreover, due to its high persistence, decreased patience compliance and emerging antibiotic resistance, researchers have been forced to search for novel candidates with lesser or no side effects. Hence, in the current study, phytobioactives have been screened for its anti-biofilm attributes against H.pylori. Gastric biopsy samples have been screened using confirmatory techniques (microbiological, biochemical and molecular) for their virulent and non-virulent biomarkers. Physico-nutritive parameters were standardized. H. pylori biofilms were assessed using microtitre plate assay. Biofilms' biomass and exopolysaccharide have been evaluated using crystal violet and ruthenium red staining, respectively. Anti-biofilm screening was performed using potent aqueous phytochemicals namely Acorus calamus, Colocasia esculenta and Vitex trifolia. The results indicated the confluent growth of the H. pylori biofilms confirmed through genotyping and grew best at 37 °C for 72 h at a pH of 7.5 on polystyrene plates. Further, among the phytochemicals tested, Acorus calamus exhibited the highest H. pylori anti-biofilm activity via a dose-dependent pattern. The overall observations of the study will pave way for newer approaches to understand and combat bacterial pathogenesis and will contribute towards better health and hygiene.

Bacteriocins are ribosomally-synthesized antimicrobial peptides or proteinaceous compounds produced by bacterial strains. They are generally effective in inhibiting the growth of similar or closely related bacterial strains. A high diversity of various bacteriocins is produced by many lactic acid bacteria (LAB) and is found in numerous fermented and non-fermented foods. Several bacteriocins from LAB extend potential applications in food preservation, thus help foods to be naturally preserved and richer in organoleptic and nutritional properties. Though chemical preservatives for the preservation of food are successful to some extent, their quality is not as satisfying as fresh food. Hence, an alternative is required and bacteriocins serve the purpose. Nisin is currently the only bacteriocin widely used as a food preservative. Numerous bacteriocins have been characterized chemically, biochemically, genetically and also at the molecular level to understand their basic mode of action. This article gives an overview of classification of bacteriocins, isolation & characterization, and mode of action. Besides, article highlights the optimized parameters for growth of bacteria in the production of bacteriocins and various bioassays for their determination. Special emphasis has been provided on explaining the beneficial aspects of nisin.

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The present study reports the phytogenic synthesis of silver nanobactericides using Acorus calamus L. and their antibiofilm activity against clinically isolated H. pylori. The synthesis was confirmed with change in the color of the reaction mixture to brown. The increased in the color intensity was periodically monitored with UV-visible spectroscopy which displayed maximum absorption at 410 nm. The biomolecular interaction was studied with FTIR spectral measurements of silver nanobactericides which revealed the presence of broad absorbance band appearing at 3361 is due to OH group and the prominent peak at 1634 correspond to an amide group. X-ray diffraction (XRD) displayed Bragg's intensities at 2θ angle reflecting (111), (200), (220) and (311) of the face centered cubic (fcc) structure of silver which was compared with standard XRD pattern. The morphological characteristics of nanobactericides were studied using Transmission electron microscopy (TEM) analysis which revealed the polydispersity of nanoparticles with size ranging from 5 to 60 nm. The anti-biofilm activity of silver nanobactericides against H. pylori was measured using crystal violet and ruthenium red assays which revealed 350 µg/mL to be more effective. The obtained activity was validated with standard antibiotics amoxicillin. Overall, the results obtained in the present investigation are promising enough to reveal the efficacy of silver nanoparticles to inhibit the biofilm production.