Antibacterial and antifungal activity of methanolic extracts of Salix alba L. against various disease causing pathogens

The present study was aimed to manifest the antibacterial and antifungal activity of methanolic extracts of Salix alba L. against seven Gram-positive and Gram-negative bacterial pathogens e.g. Streptococcus pyogenes, Staphylococcus aureus (1), S. aureus (2), Shigella sonnei, Escherichia coli (1), E. coli (2) and Neisseria gonorrhoeae and three fungal isolates from the air such as Aspergillus terreus, A. ornatus, and Rhizopus stolonifer. Two different serotypes of S. aureus and E. coli were used. The agar well-diffusion method results showed the dose-dependent response of plant extracts against bacterial and fungal strains while some organisms were found resistant e.g. E. coli (1), S. sonnei, A. terreus and R. stolonifer. The highest antibacterial activity was recorded at 17.000±1.732 mm from 100 mg/mL of leaves methanolic extracts against S. pyogenes while the activity of most of the pathogens decreased after 24 h of incubation. The highest antifungal activity was reported at 11.833±1.0 mm against A. ornatus at 50 mg/mL after 48 h of the incubation period. These experimental findings endorse the use of S. alba in ethnopharmacological formulations and suggest the use of methanolic extracts of the said plant to develop drugs to control the proliferation of resistant disease causing pathogenic microbes.

Pharmacology and Phytochemistry of Coriander

Coriander, named as Coriandrum sativum Linn, belongs to the family Umbelliferae and is one of the most popular and well-known spices/condiments and herbal medicines. The essential oils and fatty oils are the two major active chemical constituents present in the plant. The other minor ingredients found to be present are monoterpenes hydrocarbons i-e limonene, γ-terpinene, α-pinene, p-cymene, borneol, citronellol, camphor, geraniol, and geraniol acetate and abd heterocyclic components such as pyrazine, pyridine, thiazole, furan and tetrahudrofuran derivatives, isocoumarins, coriandrin, dihydrocoriandrin, coriandrons A-E, flavonoids. The volatile oil from the leaf contains aromatic acids such as 2-decenoic acid, E-11-tetradecenoic acid, undecyl alcohol, tridecanoic acid, capric acid, undecanoic acid, and more. The current pharmacological research reveals the application of coriander has antibacterial and antifungal activity.

Design and Synthesis of Some New Derivatives of Chlorobenzyl-Oxy-Phenyl-Ethyl-Thio-1H-Tetrazole and Study Their Antibacterial and Antifungal Activity

In recent years tetrazole scaffolds have been attracted interest in the field of synthetic and medicinal chemistry research. The unique structure of the tetrazole derivatives exhibits widespread applications in biology and technology. The close structural resemblance with carboxylic acid acts as a booster of the latter. Due to this diversified potential utilization, several methods are reported for the synthesis of tetrazole scaffolds. Here in this chapter, we describe the synthesis of chlorobenzyl-oxy-phenyl-ethyl-thio-1H-tetrazole derivatives ( 6a-p ). The newly synthesized derivatives are characterized by spectral characterization and screened for their antifungal activity. Among these, some of the newly synthesized compounds show potent antifungal activity.

Molecular Basis of Antibiotic Self-Resistance in a Bee Larvae Pathogen

Paenibacillus larvae, the causative agent of the devastating honey-bee disease American Foulbrood, produces the cationic polyketide-peptide hybrid paenilamicin that displays high antibacterial and antifungal activity. Its biosynthetic gene cluster contains a gene coding for the N-acetyltransferase PamZ. We show that PamZ acts as self-resistance factor in P. larvae by deactivation of paenilamicin. Using tandem MS, NMR spectroscopy and synthetic diastereomers, we identified the N-terminal amino group of the agmatinamic acid as the N-acetylation site. These findings highlight the pharmacophore region of paenilamicin, which we very recently identified as a new ribosome inhibitor. Here, we further elucidated the crystal structure of PamZ:acetyl-CoA complex at 1.34 Å resolution. An unusual tandem-domain architecture provides a well-defined substrate-binding groove decorated with negatively-charged residues to specifically attract the cationic paenilamicin. Our results will help to understand the mode of action of paenilamicin and its role in pathogenicity of P. larvae to fight American Foulbrood.

Antibacterial and antifungal activity of intraoral products containing phthalocyanine: in vitro study

The present study aimed to evaluate the in vitro antiseptic efficacy of a mouthwash and a dental gel containing phthalocyanine derivatives (Pc) against bacteria and fungi frequently found in patients with ventilator-associated pneumonia. The experiment in this study was conducted following Good Laboratory Practices. The product was tested at concentrations of 0.015% (mouthwash) and 0.100% (dental gel). The contact time of the suspension test (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella sp., Candida albicans, and Aspergillus niger) was 60 s (1 min). In this analysis, the Phtalox® Mouthwash and Dental Gel resulted in a 99.99% reduction against the tested microorganisms after 1 min of contact time in both products. The Pc-containing mouthwash and dental gel were effective against bacteria and fungi found in patients with ventilator-associated pneumonia.

Synthesis, characterization and antimicrobial activity of novel tetrazoles clubbed with pyrimidine

An attempt was made to synthesize pyrimidine tetrazole derivatives of pharmaceutical interest by oxidative cyclization of chalcones with adequate yield and purity, prompted by the diversity of their wider usage and the fact that they are an integral part of genetic content. The present work involves the reaction of 5-(2,6-dimethylphenyl)-1H-tetrazole with acetic anhydride to yield 1-[5-(2,6-dimethylphenyl)-1H-tetrazol-1-yl] ethanone (1) and which then treated with different aromatic aldehydes in presence of alkaline medium to chalcones (2a-f). Reaction of chalcones (2a-f) with urea and thiourea to produce 5-[5-(2,6-dimethylphenyl)-1H-tetrazol-1-yl]-4-(substituted aryl ) pyrimidin-2-ol (3a-f) and 5-[5-(2,6-dimethylphenyl)-1H-tetrazol-1-yl]-4-(substituted aryl) pyrimidin-2-thiol (4a-f) respectively. All compounds were characterized by infrared spectroscopy (IR), H nuclear magnetic resonance (NMR), and mass spectrometry (MS) to prove the structure and assessed in vitro for their efficacy as antibacterial and antifungal activity against four bacteria. The compounds 3c, 3d and 3f and compounds 4c, 4d and 4f possess very good activity against and E. coli and the compounds 3e, 3c and 3a and compounds 4e,4b and 4c possess very good activity against fungi and .

Inactivation of Salmonella enterica and Colletotrichum gloeosporioides on Whole Mangoes by Application of an Antimicrobial Coating Containing Oregano Essential Oil

Mangoes are susceptible to bacterial and fungal contamination during storage and transportation. This study investigated the effectiveness of pectin-based coatings containing oregano essential oil (OEO) to reduce Salmonella enterica contamination and decrease anthracnose disease on whole mangoes. A cocktail of five strains of Salmonella spp. and Colletotrichum gloeosporioides strains was spot inoculated in mangoes to verify the antibacterial and antifungal activity of OEO. The inoculated mangoes were coated with pectin-based coatings containing 0, 0.5, 0.7, and 0.9% OEO. Coated fruits were stored for 11 days at 25 °C and 90% of relative humidity. All treatments with OEO effectively inhibited the growth of Salmonella, causing a reduction of 2.5 CFU/cm2 compared to the control treatment (0% OEO). In addition, coatings effectively inhibited the growth of C. gloeosporioides on the mango surface after 9 days of storage to the same extent as the traditional Prochloraz fungicide. The efficacy of coatings treatments was between 88.06 and 96.68% compared to the control treatment. Sensory analysis showed that the OEO did not affect the quality attributes of coated mango. Results showed the potential benefits of applying the pectin-based coatings with OEO as an alternative to control S. enterica and C. gloeosporioides in whole mangoes.