Search bioRxiv⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/2023.01.03.522596

Antibacterial activity of ethanolic and aqueous extracts of Zingiber officinale on Streptococcus pneumoniae and Pseudomonas aeruginosa

RUKUNDO, A.·OMARA, D.·MAJALIJA, S.·ODUR, S.·ALAFI, S.·OKECH, S. G.
View original source ↗Export metadata ↓

Abstract

BackgroundStreptococcus pneumoniae, a capsulated lancet gram-positive bacterium, is the leading cause of mortality and morbidity among children globally and is the primary cause of pneumonia. Pseudomonas aeruginosa is an opportunistic human pathogen and the leading cause of nosocomial infections, among patients who are admitted to intensive care units. With the increasing resistance of microorganisms to antibiotics, there is a shift of choice from allopathy to naturopathy, where herbs are common ingredients of medicines and components of treatment protocols. It is against this background that this study aimed to investigate the susceptibility of P. aeruginosa and S. pneumoniae to ethanolic and aqueous extracts of ginger using the agar well diffusion technique. MethodologyAbsolute (95%) Ethanol and distilled water were used as solvents to make extracts from the ginger powder. The filtrate was dried, and the resulting substance was used to conduct antimicrobial tests on Streptococcus pneumoniae and Pseudomonas aeruginosa isolates using the agar well diffusion technique. The diameters of inhibition zones were measured, and statistical analysis was done by one-way ANOVA. Minimum inhibitory and bactericidal concentrations were determined by serial dilution. Freshly prepared sterile distilled water was used as negative control and ciprofloxacin (5 g/disk), an antibiotic was used as positive control. ResultsThe test organisms were sensitive to both ethanolic and aqueous extracts of ginger. However, this was highly dependent on the concentrations of the extracts. The ethanolic extract had lower Minimum Inhibitory and Bactericidal Concentrations than aqueous extract on both bacterial species and at a concentration of 2g/ml, the ethanolic extract was 2-fold and 1.6-fold more effective in inhibiting the growth of P. aeruginosa and S. pneumoniae respectively than aqueous extract. ConclusionWith the high susceptibility of the tested bacterial isolates to the ginger extracts used in this study, it is evident that ginger extracts can serve as a suitable antibiotic. However, further studies need to be conducted on the antimicrobial effects of ginger extracts on other bacterial species.

Explore related subjects

microbiologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

RUKUNDO, A., OMARA, D., MAJALIJA, S., ODUR, S., ALAFI, S., OKECH, S. G.. 2023-01-04. Antibacterial activity of ethanolic and aqueous extracts of Zingiber officinale on Streptococcus pneumoniae and Pseudomonas aeruginosa. https://doi.org/10.1101/2023.01.03.522596

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

A conserved cysteine-histidine-glutamate metal site identifies DUF501 (Rv1025), an essential uncharacterised protein family of Mycobacterium tuberculosis, as a candidate metalloenzyme and drug target

A substantial fraction of the Mycobacterium tuberculosis proteome remains functionally uncharacterised. Rv1025, a 155-residue protein carrying the domain of unknown function DUF501 (Pfam PF04417), is essential by transposon mutagenesis and vulnerable by CRISPR interference, an attractive but neglected drug target, yet has never been functionally described. The family (4,370 proteins, no Gene Ontology term, no solved structure) is uncharacterised across all organisms and essential in three Actinobacterial genera. A Foldseek search of the AlphaFold model against complete structural databases finds no significant homolog, indicating a novel fold. The operon eno-divIC-Rv1025-ppx2 is conserved across the Actinobacteria phylum, yet AlphaFold-Multimer finds no direct complex between Rv1025 and its neighbour DivIC. Instead, conservation across 8,700 homologous sequences reveals a near-invariant Cys113-His115-Glu59 cluster forming a pocket. Holo AlphaFold3 predictions with Zn, Fe and Mn confidently place a divalent metal on this triad at 2.25-2.47 A; mutating the triad relocates the metal, and an independent backbone-geometry predictor recovers the same site, confirming specificity. The triad is universal across the family: present in all 1,472 near-complete bacterial sequences of the Pfam alignment, with no non-conservative substitution among the 2,228 sequences examined, a defining feature of bacterial DUF501 rather than a mycobacterial peculiarity. We propose that DUF501 is a metal-binding protein and candidate metalloenzyme, the first functional hypothesis for this family, whose conserved, essential metal pocket is a promising drug target. As the predictions build on a conservation-defined site within a fully computational study, they are supportive rather than proof of metal occupancy and warrant experimental validation.

microbiology↗
bioRxiv2026

Mycoplasmal endosymbionts of Trichomonas vaginalis are associated with reduced risk for Chlamydia trachomatis endometrial infection in asymptomatic, coinfected, women.

Trichomonas vaginalis is a protozoan parasite that causes trichomoniasis, the most common curable non-viral sexually transmitted infection, and Chlamydia trachomatis is a bacterial pathogen that can ascend to the upper genital tract and cause pelvic inflammatory disease, infertility, and ectopic pregnancy. T. vaginalis harbors bacterial endosymbionts, including Candidatus Malacoplasma girerdii, an obligate symbiont, and Metamycoplasma hominis, which can live freely or symbiotically. In a 16S rRNA sequencing study of the cervicovaginal microbiome of women at high risk for chlamydial infection, Ca. M. girerdii abundance was one of 13 features predicting lack of chlamydial spread to the endometrium, despite no direct association between T. vaginalis infection and reduced chlamydial ascension. Investigating the relationship between these microorganisms further, we found that T. vaginalis vaginal abundance correlated positively with chlamydial burden in women whose infection was confined to the cervix, while a nonsignificant inverse relationship was seen in women with endometrial spread. Among participants with high chlamydial burden, Ca. M. girerdii was detected exclusively in women without endometrial infection. Both endosymbionts trended toward more frequent detection, and higher abundance, in coinfected women without endometrial spread, while M. hominis abundance correlated strongly with T. vaginalis burden in this group. These findings suggest that mycoplasmal endosymbionts of T. vaginalis, rather than T. vaginalis itself, are microbial factors limiting chlamydial ascension, and point to a three-way interaction between parasite, endosymbiont, and bacterial pathogen that shapes upper genital tract C. trachomatis infection risk.

microbiology↗
bioRxiv2026

Understanding the physiological alterations of Vibrio cholerae upon exposure to L-ascorbic acid

The scourge of cholera remains a major global public health threat. It affects up to 4 million people worldwide and causes tens of thousands of deaths each year. The disease is experiencing a concerning resurgence in many parts of Africa, the Middle East, and Asia. To effectively tackle cholera and circumvent rising antimicrobial resistance, targeted biological and preventive approaches, complementing traditional rehydration, are urgently needed. In this regard, our group has demonstrated the efficacy of L-ascorbic acid in controlling the growth and pathogenesis of Vibrio cholerae in vitro. The present work further provides a mechanistic elucidation of the L-ascorbic acid-mediated physiological changes in V. cholerae and also bolsters such a non-antibiotic approach to control cholera.

microbiology↗