Comparative study of in-vitro antimicrobial activity and phytochemical composition of Sida cuneifolia fruits, leaves, and stem bark extracts

Background: Sida cuneifolia plant parts are important in ethno-veterinary medicine, but no studies exist on a comparative evaluation of phytochemical composition and antimicrobial properties of fruits, stem bark and leaves. This study evaluated and compared extraction yields, phytochemical composition as well as antibacterial and antifungal properties of ether, methanol and aqueous crude extracts of fruits, leaves, and stem bark of S. cuneifolia.Methods: Yields of extracts were determined, and qualitative phytochemical screening tests were carried out to establish their composition. Crude extracts were screened against five bacteria and two fungi. Agar disk diffusion technique was used to determine the inhibition zone diameters. Broth micro-dilution method was used to determine the minimum inhibition concentrations (MIC) and minimum bactericidal concentrations (MBC).Results: Triterpene aglycones, sterols, tannins, athracene derivatives, polyuronides and glucides were found in intense mounts in S. cuneifolia fruits. Leaves contained intense amounts of carotenoids, tannins, polyuronides and coumarin derivatives. For the leaves, methanol extracts had MICs and MBCs as low as (≤3.13 mg/ml) against the majority (6/7) microorganisms hence had the best activity. Considering the stem bark, the ether extracts had the best antimicrobial activity with MICs as low as ≤3.13 mg/ml against 6/7 microorganisms. For the fruits, the ether extracts had the best antibacterial activity with MICs and MBCs as low as (≤3.13 mg/ml) against all tested bacteria.Conclusion: The study provides scientific evidence for ethno-veterinary use of S. cuneifolia leaves, fruits and stem bark, and this can be exploited in the transformative development of ethno-medicine

A review of phage mediated antibacterial applications

Background: For over a decade, resistance to newly synthesized antibiotics has been observed worldwide. The challenge of antibiotic resistance has led to several pharmaceutical companies to abandon the synthesis of new drugs in fear of bacteria developing resistance in a short period hence limiting initial investment return. To this effect, alternative approaches such as the use of bacteriophages to treat bacterial infections are being explored. This review explores the recent advances in phage-mediated antibacterial applications and their limitations.Methods: We conducted a comprehensive literature search of PubMed, Lib Hub and Google Scholar databases from January 2019 to November 2019. The search key words used were the application of bacteriophages to inhibit bacterial growth and human phage therapy to extract full-text research articles and proceedings from International Conferences published only in English.Results: The search generated 709 articles of which 95 full-text research articles fulfilled the inclusion guidelines. Transmission Electron Microscopy morphological characterization conducted in 23 studies registered Myoviruses, Siphoviruses, Podoviruses, and Cytoviruses phage families while molecular characterization revealed that some phages were not safe to use as they harbored undesirable genes. All in vivo phage therapy studies in humans and model animals against multidrug-resistant (MDR) bacterial infection provided 100% protection. Ex vivo and in vitro phage therapy experiments exhibited overwhelming results as they registered high efficacies of up to 100% against MDR clinical isolates. Phage-mediated bio-preservation of foods and beverages and bio-sanitization of surfaces were highly successful with bacterial growth suppression of up to 100%. Phage endolysins revealed efficacies statistically comparable to those of phages and restored normal ethanol production by completely eradicating lactic acid bacteria in ethanol fermenters. Furthermore, the average multiplicity of infection was highest in ex vivo phage therapy (557,291.8) followed by in vivo (155,612.4) and in vitro (434.5)

Influence of physicochemical parameters on storage stability: Microbiological quality of fresh unpasteurized fruit juices

Fresh juices rich in health and nutritional benefits are valued for their fresh flavor, taste, and aroma. These juices' quality however is affected by factors like temperature, light, and microbiological contamination significantly changing physicochemical parameters and storage stability. Physicochemical and microbiological analyses of passion fruit, pineapple, and mango juices in dark and light bottles at 24°C and 4°C were conducted in Kampala, Uganda for 12 days. Physicochemical parameters significantly reduced (p < .05) storage stability of fresh juices, while no significant changes (p > .05) were observed for the microbiological analyses. pH values ranged from 3.0 to 4.2 (dark) bottles and 2.9 to 4.0 (light) bottles for juices at 24°C and 4°C. °Brix values were from 1.0 to 5.5 for dark and clear bottles at 24°C and 4°C. TTA (%) values ranged from 1.1 to 7.2 (dark) bottles and 1.1 to 7.4 for (light) bottles at 24°C and 4°C. Ascorbic acid content ranged from 3.5 to 61.0 mg/ 100 ml and 5.5 to 56.7 mg/100 ml for juices in dark and clear bottles, respectively. total plate counts ranged from 1.3 × 10___ to 3.3 × 107 CFU/ml (dark bottles at 24°C) to 3.5 × 10³ to 3.3 × 108 CFU/ml (dark bottles at 4°C). For juices in light bottles, total plate counts ranged from 1.8 × 10___ to 8.0 × 107 CFU/ml (24°C) and 2.7 × 10___ to 1.5 × 108 CFU/ml (4°C). High microbial loads suggest the use of poor processing techniques and lack of good hygiene which lower quality and reduce storage stability of juices. Storage temperature greatly reduces physicochemical parameters both at ambient and refrigeration temperatures. This implies that temperature control for unpasteurized juices is critical in order to inhibit microorganism metabolic activities which accelerate biodeterioration leading to spoilage and short shelf life. Fresh unpasteurized juices stored at 24°C and 4°C may safely be consumed within 1 and 2 days, respectively

Bacterial Viruses Subcommittee and Archaeal Viruses Subcommittee of the ICTV : update of taxonomy changes in 2021

In this article, we - the Bacterial Viruses Subcommittee and the Archaeal Viruses Subcommittee of the International Committee on Taxonomy of Viruses (ICTV) - summarise the results of our activities for the period March 2020 - March 2021. We report the division of the former Bacterial and Archaeal Viruses Subcommittee in two separate Subcommittees, welcome new members, a new Subcommittee Chair and Vice Chair, and give an overview of the new taxa that were proposed in 2020, approved by the Executive Committee and ratified by vote in 2021. In particular, a new realm, three orders, 15 families, 31 subfamilies, 734 genera and 1845 species were newly created or redefined (moved/promoted).Non peer reviewe

Abolishment of morphology-based taxa and change to binomial species names: 2022 taxonomy update of the ICTV bacterial viruses subcommittee

Peer reviewe