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Abstract Hydroquinone, Mercury (Hg), and Arsenic (As) are hazardous to health upon long-term exposure. Hydroquinone, Hg, and As were analysed in skin-lightening cosmetics randomly purchased from different cosmetic outlets within the Ilorin metropolis, Nigeria. The amount of hydroquinone in the samples was determined using a UV-spectrophotometry method at 290 nm. Hg and As were quantified using atomic absorption spectrophotometry (AAS). UV-spectrophotometry method validation showed excellent linearity (r2 = 0.9993), with limits of detection (0.75 µg/mL), limits of quantification (2.28 µg/mL), relative standard deviation (0.01–0.35%), and recovery (95.85–103.56%) in the concentration range of 5–50 µg/mL. Similarly, r2, LOD, and LOQ for Hg and As were 0.9983 and 0.9991, (0.5 and 1.0 µg/L) and 1.65 and 3.3 µg/L) respectively. All the samples contained hydroquinone, Hg and As in varying amounts. The amounts of hydroquinone, Hg and As present were in the ranges of 1.9–3.3%, 0.08–2.52 µg/g and 0.07–5.30 µg/g respectively. Only three of the analysed samples contained hydroquinone within the permissible limit of 2.0% w/w in cosmetic products. All the samples analysed contained mercury and arsenic in varying amounts. The need to periodically monitor the levels of hydroquinone, mercury, and arsenic in skin-lightening cosmetics marketed in Nigeria is recommended.

Human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) constitutes a source of great concern to health authorities worldwide. Herbal medicinal products are used as a significant treatment option for highly active antiretroviral therapies, the efficacies of which are negatively impacted by the emergence of multidrug-resistant strains to the recommended treatment guidelines. This review provides an updated synopsis of available documents on herbal medicinal products with anti-HIV activities. Concurrent consumption of herbal products with conventional drugs, which is often necessitated by co-morbidity of HIV with other diseases, can potentially alter the pharmacokinetics of the co-administered orthodox drugs. Phytochemical constituents of the herbal medicinal products with antiretroviral activities were identified, and their potential to mediate pharmacokinetic changes through modulation of drug-metabolizing enzymes and P-glycoprotein was reported. Herb-drug interactions (HDIs) that can result in significant adverse effects were also discussed with documenting the information for the therapeutic utility of these clinically effective antiretroviral herbal medicinal products with potential for development into newer anti-HIV drugs.

Various epidemiological researches have shown that consumption of vegetables and fruits are essential to maintain health and prevent diseases but the emergence of more and more drug resistance bacteria has led to high mortality. Thus the study of the antimicrobial and antioxidant activities of a flavonoid (Catechin-3-o-rhamnoside) isolated for the first time from Lannea kerstingii. Catechin-3-o-rhamnoside was isolated using dry vacuum liquid chromatography. It was characterized using 1 H-NMR, 13 C-NMR and 2D NMR spectra. The antimicrobial activity was determined using agar diffusion and broth dilution method. Antioxidant activity was determined through reaction of the compound with DPPH radical. The compound was active against, Methicillin Resistant Staphylococcus aureus, S. aureus, B. subtilis, E. coli, K. pneumoniae, S. typhi, S. dysentariae, C. albicans and C. tropicalis with zone of inhibition ranging from 22.0±0.1 to 35.0±0.2mm and inactive against vancomycin resistant enterococci, Proteus mirabilis and C. ulcerans. The MIC ranged from 6.25 to 12.5μg/ml while the MBC/MFC ranged from 12.5 to 50.0μg/ml. The compound showed a high radical scavenging activity with EC 50 of 46.87µg/ml. These results show a potential lead drug for resistant bacteria and natural antioxidants.