Annona muricata, also called soursop, is widespread in many tropical countries, and various parts of the plant have been shown to possess very good pharmacological properties. This work evaluated the chemical composition and antioxidant activities of essential oils obtained from the fruit pulp and leaves of soursop. Essential oils were obtained via hydrodistillation and characterized by gas chromatography-mass spectrometry. Antioxidant potential was evaluated via the phosphomolybdenum, hydrogen peroxide scavenging, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assays. In the leaf essential oil, a total of 31 compounds were identified with δ-cadinene (22.58%) and α-muurolene (10.64%) being the most abundant. Thirty-two compounds were identified in the fruit pulp essential oil with Ç-sitosterol (19.82%) and 2-hydroxy-1-(hydroxymethyl) ethyl ester (13.48%) being present in high amounts. Both essential oils showed very good total antioxidant capacities (49.03 gAAE/100 g and 50.88 gAAE/100 g for fruit pulp and leaf essential oils, respectively). The IC50 values from the DPPH assay were 244.8 ± 3.2 μg/mL for leaf essential oil and 512 ± 5.1 μg/mL for the fruit pulp essential oil. At 1 mg/mL, hydrogen peroxide scavenged was below 50% for both leaf and fruit pulp essential oils, indicating moderate activity. These results suggest possible application of the essential oils of Annona muricata in food preservation and processing.

The ongoing global pandemic caused by the human coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected millions of people and claimed hundreds of thousands of lives. The absence of approved therapeutics to combat this disease threatens the health of all persons on earth and could cause catastrophic damage to society. New drugs are therefore urgently required to bring relief to people everywhere. In addition to repurposing existing drugs, natural products provide an interesting alternative due to their widespread use in all cultures of the world. In this study, alkaloids from Cryptolepis sanguinolenta have been investigated for their ability to inhibit two of the main proteins in SARS-CoV-2, the main protease and the RNA-dependent RNA polymerase, using in silico methods. Molecular docking was used to assess binding potential of the alkaloids to the viral proteins whereas molecular dynamics was used to evaluate stability of the binding event. The results of the study indicate that all 13 alkaloids bind strongly to the main protease and RNA-dependent RNA polymerase with binding energies ranging from -6.7 to -10.6 kcal/mol. In particular, cryptomisrine, cryptospirolepine, cryptoquindoline, and biscryptolepine exhibited very strong inhibitory potential towards both proteins. Results from the molecular dynamics study revealed that a stable protein-ligand complex is formed upon binding. Alkaloids from Cryptolepis sanguinolenta therefore represent a promising class of compounds that could serve as lead compounds in the search for a cure for the corona virus disease.

The incidence of antimicrobial resistance among microbial communities is a major threat to global health care and security. Landfills, which are reservoirs for many pharmaceuticals, provide a conducive habitat for antimicrobial-resistant microbes and resistant gene transfer and are therefore a major contributor to the phenomenon of antimicrobial resistance. Hence, this study determined the levels of three widely used antibiotics, metronidazole, penicillin, and amoxicillin, and the occurrence of antimicrobial resistance amongst microbes in soil and leachate samples from active and abandoned landfill sites in Kumasi, Ghana. Soil samples were collected from one active and four abandoned landfills, while leachate specimen was collected only from the active landfill. Sonication and solid-phase extraction (SPE) were used for sample preparation, followed by analysis via an HPLC-PDA method. Isolation and characterization of bacteria were done using standard bacteriological techniques. Antibiotic susceptibility testing was determined following the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. Antibiotics were detected at very high concentrations in the specimen collected from both active and abandoned landfill sites. For leachate samples obtained from Dompoase, penicillin was present at the highest concentration (67.42 ± 5.35 μg/mL, p<0.05) followed by metronidazole (18.25 ± 7.92 μg/mL) and amoxicillin (10.96 ± 6.93 μg/mL). In general, the levels of antibiotics in soil samples were similar at both active and abandoned landfill sites. Nonetheless, as with leachates, penicillin levels were much higher (p<0.05) than levels of amoxicillin and metronidazole within any particular site. When screened against some antibiotics, Enterobacteriaceae and some Bacillus and Listeria species isolated from the soil and leachate samples proved to be resistant. The high levels of antibiotics coupled with the presence of resistant microbes at these landfills sites call for immediate measures to halt the disposal of pharmaceuticals in the environment so as to avert any possible public health setback.

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e use of organochlorine pesticides has been banned worldwide due to their toxicities. However, some farmers use them illegally because of their potency. e aim of this study was to assess the level of organochlorine pesticide (OCP) residues and the potential health risk associated with vegetables, soil, and groundwater obtained from farms in Ayigya, Nsenie, Gyenyase, and Kentinkrono in Kumasi, Ghana. A total of 15 samples were analyzed using a gas chromatograph equipped with an electron capture detector. e highest mean concentration of 184.10 ± 12.11 µg/kg was recorded for methoxychlor in cabbage from Ayigya. Betahexachlorocyclohexane (beta-HCH) recorded the lowest mean concentration of 0.20 ± 0.00 µg/kg in cabbage from Ayigya. e combined risk index showed significant health risk to children than adults. e soil samples mainly contained methoxychlor followed by dichlorodiphenyltrichloroethane (DDT), aldrin, and other OCPs. Concentrations of total HCHs, total DDTs, and total OCPs in the soil samples ranged from <0.01 to 49.00, <0.01 to 165.81, and <0.01 to 174.91 µg/kg, respectively. Among all HCH and DDT isomers, only β-HCH and p,p′-DDT were detected in some of the water samples. Carcinogenic risk values for β-HCH, aldrin, and p,p′ DDT in the groundwater were found to be >10 −6 , posing a potentially serious cancer risk to consumers. Moreover, the hazard quotients (HQs) of aldrin exceeded the threshold value of one, indicating that daily exposure is a potential concern.