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The microplastisphere is a dense consortium of metabolically active microorganisms that develops on the surface of microplastics. Since the discovery that it harbors antibiotic resistance genes (ARGs), there has been a quest to decipher the relationship between ARG occurrences and selective enrichment with plastic types, which is important to understand their fate in diverse environmental settings. Nonetheless, it remains a neglected topic, and this developing field of microplastics research could benefit from a comprehensive review to acquire a deeper understanding of the most recent advances and drive scientific progress. Accordingly, the goal of this review is to critically discuss and provide an in-depth assessment of the evidence of ARGs' global nature in microplastispheres, as well as explore factors that influence them directly and indirectly, highlighting important concerns and knowledge gaps throughout the article. By comprehensively covering them, we underscore the potential environmental implications associated with microplastisphere ARGs. From our analysis, it emerged that microplastisphere ARGs are likely to be impacted not only by differences in microplastic types and characteristics but also by how their environments are shaped by other agents such as physiochemical properties, socioeconomic factors, and contaminants coexistence, influencing ARG subtype, incidence, abundance, and selective enrichment. The intricate relationship of microplastisphere ARGs to environmental conditions and plastic types calls for multilevel investigations to clearly assess the environmental fate of microplastics. We anticipate that this review could assist researchers in strengthening their foundation and identifying efforts to advance knowledge in this research field., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

New morpholine derived Schiff base ligands (HL 1 and HL 2 ) and their Cu(II) complexes [Cu(L 1 ) 2 ] (1) and [Cu(L 2 ) 2 ] (2) have been synthesized and characterized by 1 H NMR, IR, UV-Vis, EPR studies and cyclic voltammetric analyses. Single crystal X-ray crystallography studies confirm the structure of newly synthesized Schiff base ligands HL 1 and HL 2 . The ground state electronic structures of Cu(II) complexes 1 and 2 have been investigated by DFT/B3LYP theoretical analysis with 6-31G (d,p) and LANL2DZ basis set. The affinity towards DNA and protein molecules have been evaluated using computational docking analysis and complex 2 expose significant binding ability with DNA as well as protein due to its towering hydrophobicity. Consequently, complex 2 reveals superior antibacterial activity against some bacterial species besides anticancer activity on human breast cancer (MCF-7) cells than complex 1 and Schiff base ligands (HL 1 and HL 2 ). These preliminary investigations strongly recommended that complex 2 can be used as a better antibacterial plus anticancer agent., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Production of AgNPs with desired morphologies and surface characteristics using facile, economic and non-laborious processes is highly imperative. Cell extract based syntheses are emerging as a novel technique for the production of diverse forms of NPs, and is assured to meet the requirements. Therefore, in order to have a better understanding, and to improvise and gain control over the NPs morphological and surface characteristics, the present investigation systematically evaluates the influence of various major physico-cultural parameters including diverse growth media, concentrations of precursor salts; pH and temperature on the biotransformation of ionic silver (Ag + ) to nanopariculate silver nanoparticles (AgNPs), utilizing the cell free extract of the bacterium, P. plecoglossicida. The synthesis, purity, morphology and surface characteristics of the AgNPs during optimization studies were measured. The bactericidal effect of these AgNPs was assessed using multi-drug resistant human pathogens; Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa and Salmonella enterica based on the diameter of inhibition zone in disk diffusion tests. The nanoparticles were found to be of higher toxicity to E. coli and S. enterica than A. baumannii and P. aeruginosa. The results demonstrate that the chosen parameters in whole or in part could have a significant influence on the morphology, surface characteristics, duration of production, overall yield and production of AgNPs., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Porous chitosan membrane was fabricated by casting method using silica particles. Simultaneously nano ZnO was synthesized by green-synthesis method using tung ting oolong tea extract. Chitosan membrane was combined with nano ZnO in order to increase its antimicrobial activity. Through observations obtained from various techniques such as XRD, SEM, FT-IR, UV-visible and fluorescence emission analyses, chitosan was seen to be able to incorporate nano ZnO in the nanocomposite membrane. A blue shift (from 360 to 335 nm) was observed in the UV-visible spectrum of nanocomposite and fluorescence emission intensity of nanocomposite was considerably lower than that of nano ZnO. Gram negative organism Klebsiella planticola (MTCC2727) and Gram positive organism Bacillus substilis (MTCC3053) were used to test the antibacterial and antifouling activities of newly synthesized nanocomposite chitosan/ZnO membrane. The nanocomposite chitosan/ZnO membrane promisingly inhibited the bacterial growth when compared with as-synthesized chitosan. Gram negative K. planticola (MTCC2727) was comparatively more susceptible for inhibition than that of Gram positive Bacillus substilis (MTCC3053). In conclusion, nanocomposite obtained in this study showed enhanced antibacterial and antifouling activities. We believed that the enhanced physical properties of nanocomposite achieved by incorporating nano ZnO in the chitosan matrix could be beneficial in various applications., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Gargantulide A (1), an extremely complex 52-membered macrolactone, was isolated from Streptomyces sp. A42983 and displayed moderate activity against MRSA. The planar structure of 1 was determined using 2D NMR, and its stereochemistry was partially established on the basis of NOESY correlations, J-based configuration analysis, and Kishi's universal NMR database., Competing Interests: Notes The authors declare no competing financial interest.

Simple, nontoxic, environmental friendly method is employed for the production of silver nanoparticles. In this study the synthesized nanoparticles UV absorption band occurred at 400 nm because of the surface Plasmon resonance of silver nanoparticles. The pH of the medium plays important role in the synthesis of control shaped and sized nanoparticles. The colour intensity of the aqueous solution varied with pH. In this study, at pH 9, the colour of the aqueous solution was dark brown, whereas in pH 5 the colour was yellowish brown; the colour difference in the aqueous solution occurred due to the higher production of silver nanoparticles. The antibacterial activity of biosynthesized silver nanoparticles was carried out against E. coli. The silver nanoparticles synthesized at pH 9 showed maximum antibacterial activity at 50 μL.

Root canal infections are polymicrobial in nature, consisting of both aerobic and anaerobic species. The successful treatment of both primary and secondary endodontic infections involves effective eradication of the causative microorganisms during root canal treatment procedures. Reduction and elimination of microorganisms from the infected root canal provides optimal opportunity for treatment success. Local application of antibiotics has been considered an effective way to deliver antibiotics. A combination of antibiotic drugs have been tried under the concept of lesion sterilization and tissue repair therapy to eliminate the target bacteria, which are possible sources of endodontic lesions. The purpose of this article is to discuss the lesion sterilization and tissue repair therapy technique in primary teeth.

Several marine fungi collected from the waters of Prince Edward Island, Canada, were screened for the presence of natural products exhibiting antibacterial activity. Both broths and mycelia of these fungi were studied using the bioassay-guided chromatographic separation. The 4 fractions from the extract of mycelia of Corollospora lacera exhibited weak antibacterial activity and were analyzed further. From these fractions, 2 sterols (5 alpha,8 alpha-epidioxyergosterol and 22E,24R-ergosta-7,22-diene-3beta,5 alpha,6 beta-triol) and a 3:1 mixture of linoleic and oleic acids were isolated. The presence of ergosterol was confirmed in dichloromethane extracts of mycelia of every fungus in this study and this sterol was isolated from the extract of mycelium of Corollospora lacera. Two other known compounds (5-hydroxymethylfuran-2-carbaldehyde and bis(2-ethylhexyl) phthalate), were isolated from the dichloromethane extract of mycelium of Monodictys pelagica. The phthalate was reported in the literature as a metabolite isolated from the fungi, but in our study it was proven to be an artifact of the culturing and (or) extraction procedures rather than a true fungal metabolite.