Identification and development of newer and better antimicrobials from natural products represent ongoing research efforts by many investigators. Curcumin is a polyphenol commonly found in the plant Curcuma longa (better known as turmeric). It has been reported to possess several bioactivities including antioxidant, anti-cancer, anti-inflammatory, anti-diabetic, anti-fibrotic, and antimicrobial properties. However, little is known about the antimicrobial mode of action of curcumin, thus undermining its prospects as an alternative antimicrobial agent. In this study, we investigated the mechanism of antimicrobial action by curcumin. The mechanism of inhibition was evaluated in representatives of Gram negative (Escherichia coli) and Gram positive (Staphylococcus aureus) bacteria isolates, treated with either curcumin singly or in combination with ascorbic acid (1000 μg/mL). Results showed that curcumin has broad antimicrobial capacity. In addition, curcumin only and/or co-treatment with ascorbic acid caused lipid peroxidation in S. aureus and E. coli, and by extension led to DNA damage, indicative of oxidative stress. It is plausible that the oxidative might be related to the activation of the kynurenine pathway in S. aureus but not in E. coli. Furthermore, curcumin exposure led to elevated total antioxidant capacity (TAC) and level of total thiol, but decreased nitric oxide level in the bacteria isolates. Together, the findings suggest that oxidative stress and DNA damage might be partly responsible for the antimicrobial action of curcumin.

BACKGROUND: Dysmenorrhea occurs as one of the symptoms of menstruation. While not necessarily a condition that plagues every woman, it is known to cause significant distress. Absenteeism from school and work as well as general discomfort are some of its adverse effects. AIM: This study aims to investigate the effects of certain diets on the prevalence and severity of dysmenorrhea. METHODS: Questionnaires was given to 478 women ranging from ages 1-55. The survey was centred around the age of menarche, presence and incidence of dysmenorrhea as well as how it is related to certain diets. RESULTS: Majority of the participants (81.74%) belonged to the age groups of 11-15 and 16-20. 45.5% of the participants attested to dysmenorrhea at each menstrual cycle. statistical correlation between diet and dysmenorrhea was insignificant (p > 0.05). Consumption of caffeinated beverages correlated with dysmenorrhea (p < 0.05). Although not statistically significant (p > 0.05), the study reported dysmenorrhea in a large proportion of participants who consumed high quantities of sugars. CONCLUSION: No relationship was established between diet and the incidence and severity of dysmenorrhea amongst the sample screened in Saint Vincent and the Grenadines. However, it appears that diet high in sugars might benefit from further research.

The search for new and better antimicrobial therapy is a continuous effort. Quercetin is a polyphenol with promising antimicrobial properties. However, the understanding of its antimicrobial mechanism is limited. In this study, we investigated the biochemical mechanistic action of quercetin as an antibacterial compound. Isolates of Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia, and Staphylococcus aureus were initially exposed to quercetin for antibacterial evaluation. Subsequently, S. aureus (Gram-positive) and E. coli (Gram-negative) cells were exposed to quercetin with or without ascorbic acid, and cells were harvested for selected biochemical assays. These assays included redox homeostasis (lipid peroxidation, total thiol, total antioxidant capacity), nitric oxide, and kynurenine concentration as well as DNA fragmentation. The results revealed that quercetin caused lipid peroxidation in the bacterial isolates. Lipid peroxidation may indicate ensuing oxidative stress resulting from quercetin treatment. Furthermore, tryptophan degradation to kynurenine was activated by quercetin in S. aureus but not in E. coli, suggesting that local L-tryptophan concentration might become limiting for bacterial growth. These findings, considered together, may indicate that quercetin restricts bacterial growth by promoting oxidative cellular stress, as well as by reducing the local L-tryptophan availability by activating the kynurenine pathway, thus contributing to our understanding of the molecular mechanism of the antimicrobial action of quercetin.

Salmonella Typhi is a major global concern in many low- and middle-income countries. In addition, the emergence and persistence of drug resistant strains has increased the impact of this disease. Plant metabolites have been explored traditionally and scientifically as antimicrobial agents. Thus, this study was designed to investigate the antimicrobial potential of acetone leaf fractions of H. indica against S. Typhi. Dried pulverized leaves of H. indica were extracted using cold maceration with acetone after defatting with n-hexane. The leaf extract was concentrated and subjected to column chromatography and eight bioactive fractions were identified. The fractions were characterized using gas chromatography-mass spectrometry. The fractions were evaluated for antibacterial activity against Salmonella Typhi in-vitro and in-silico. The lowest MIC was observed in fractions 20 and 21 (0.375 mg/mL) while the lowest MBC was observed in all fractions except 7, 17 and 18 (0.375 mg/mL). A ligand from fraction 8 had the highest binding affinity to Type I dehydroquinase (-3.4) and a ligand from fraction 7 had the highest binding affinity to Gyrase B (-11.2). This study concludes that the overall antimicrobial activity of the acetone leaf extract of H. indica provided evidence that it contains drug-like compounds that can be further explored as a drug candidate against S. Typhi.