In vitro antibacterial and antifungal activities of extracts and fractions of leaves of Ricinus communis Linn against selected pathogens

Abstract

Introduction Infectious disease impacts are reduced due to the development of antimicrobial agents. However, the effectiveness of antimicrobial agents is reduced over time because of the emergence of antimicrobial resistance. To overcome these problems, scholars have been searching for alternative medicines. Ricinus communis is used as a traditional treatment for bovine mastitis, wound infection, and other medicinal purposes. Objective The objective of the present study was to further evaluate the antimicrobial activities of R. communis leaf extracts and fractions. Methods R. communis leaves were macerated in methanol and acetone. The methanol extract showed better antimicrobial activity and subjected to further fractionation via increasing polarity of solvents (n‐hexane, chloroform, ethyl acetate, and aqueous). Test microorganisms included in the study were six laboratory reference bacteria (Escherichia coli, Staphylococcus aureus, Streptococcus agalactiae, Kleibsella pneumoniae, Pseudomonas aeruginosa and Streptococcus pyogenes), two clinical isolate bacteria (E. coli and S. aureus), and Candida albicans. The agar well diffusion method was employed to determine antimicrobial activity. The minimum inhibitory concentrations (MIC) and minimum bactericidal/fungicidal concentrations (MBC/MFC) were determined through broth microdilution. Results The results indicated that the best antimicrobial activity for ethyl acetate fraction ranged from 14.67 mm (clinical E. coli) to 20.33 mm (S. aureus) at 400 mg/ml, however, n‐hexane exhibited the lowest antimicrobial activity. Among the tested fractions, ethyl acetate fraction showed the lowest MIC values ranged from 1.5625 mg/ml (S. aureus) to 16.67 mg/ml (Candida albicans). The ethyl acetate fraction showed bactericidal activity against all tested microorganisms. Conclusion Hence, ethyl acetate fraction of crude methanol extract exhibited the best antimicrobial activity.

Antibacterial activity of medicinal plants on the management of mastitis in dairy cows: A systematic review

“…However, some studies which employed the separation of bioactive compounds also made an observation that some of the separated compounds have less activity compared to crude preparation (Abubakar & Haque, 2020; Bedaso & Workineh, 2022). This can be explained by the synergic activity posed by some of the bioactive compounds (Álvarez‐Martínez et al., 2021).…”

“…Qualitative analysis Identified presence of alkaloids, flavonoids, saponins, tannins, tepernoids/terpenes, steroids/phytosterols/sterols, cardiac glycosides/glycosides, phenols, anthraquinones and volatile oils (Amber et al, 2018;Bedaso & Workineh, 2022;Dharajiya et al, 2012;Gopinath et al, 2011;Šukele et al, 2022;Tripathi et al, 2018)…”

In vitro antifungal potency of the moronecidin-like peptide against Candida albicans, Candida glabrata, and Candida tropicalis

“…The minimum fungicidal concentration (MFC) was determined by spotting 50 µL aliquots from wells with no apparent growth (8 to 128 μg/ml for C. tropicalis and C. albicans and 32 to 128 μg/mL for C. glabrata ) onto SDA plates and incubating these at 30°C for 96 h. The lowest moronecidin-like peptide concentration producing less than three colonies, which corresponds to killing ≥ 99.9% of the inoculum, was defined as the MFC ( 36 ).…”

Facile Synthesis of Benzimidazoles via Oxidative Cyclization of Acyclic Monoterpene Aldehyde with Diamines: Studies on Antimicrobial and in Vivo Evaluation of Zebrafish

“…Following the first ten wells in each row, a positive control containing organisms was placed in the eleventh well, and a negative control containing no organisms was placed in the twelfth well. As a negative control, 5 mL of test bacteria cultured for 12 h was added to every other well, but the 12th, and the plates were incubated at 37 °C for 16 h. [47] 10 mL of freshly made MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium bromide) was added to each well and allowed to sit for 10 min before being added to the rest of the wells. 100 mL of dimethyl sulfoxide (DMSO) solution was added as a solubilizing agent, and the mixture was then incubated for 15 min.…”