ABIODUN FALODUN

Eleusine coracana is commonly found in the arid regions of Asia and Africa. The seeds are used locally in the management of various diseases such as diabetes, osteoporosis, anaemia, ulcer, depression and insomnia. This study was carried out to determine the antidiabetic activity of different fractions of Eleusine coracana seeds and identify compounds present in the active fractions. Proximate analysis, phytochemical screening and mineral analysis were carried out using standard methods. The powdered seed (5.5 kg) was extracted with methanol in a Soxhlet apparatus. The concentrated crude extract (100 g) was subjected to vacuum liquid chromatography using solvents of increasing polarity (n-nexane, dichloromethane, ethylacetate, 50% ethanol/ethyl, 100% methanol, 20% water/methanol, 50% water/methanol and water) to obtain different fractions. The median lethal dose was determined using Lorke’s method. Antioxidant screening, total phenols and flavonoid content determination were also carried out on the extract and fractions using 1,1, diphenyl 2 picryl hydrazyl (DPPH) free radical scavenging method, ferric reducing antioxidant power (FRAP) method, folin ciocateau and aluminium chloride test respectively. The crude extract and selected fractions at a dose of 200 and 400 mg/kg/day were screened for antidiabetic activity using streptozotocin-induced diabetic rats. The ethylacetate fraction was chromatographed to obtain fractions. Fractions with similar TLC profile were combined and selected combinations were further purified. The ethylacetate and n-hexane fraction were subjected to infrared spectroscopic (IR) analysis and Gas Chromatography-Mass Spectroscopic (GC-MS) analysis to determine the chemical constituent(s) present. The moisture content and total ash of the powdered seed were 0.38 ± 0.14 and 2.23 ± 0.13, respectively. Phytochemical screening revealed the presence of carbohydrates, proteins, xxiv alkaloids, flavonoids, tannins, reducing sugars, saponins, phenols and terpenoids. Mineral analysis revealed the presence of essential minerals such as calcium (362.20 ± 9.01), sodium (11.66 ± 1.17), potassium (19.72 ± 0.39), magnesium (1.06 ± 0.00) and zinc (0.35 ± 0.01). Heavy metals such as nickel and cadmium were not present in the sample while the others fell below WHO recommended limit for heavy metals. The median lethal dose was observed to be 5000 mg/kg/day, no mortality was observed after 24 hr and 14 days of monitoring. Antioxidant screening revealed that the 50% ethylacetate: methanol fraction had the highest antioxidant activity (IC50 = 29.65 μg/mL) as well as the highest total phenol (132.40 ± 0.51 mgGAE/g) content compared to the crude extract and fractions. The crude extract and fractions at 200 and 400 mg/kg/day dose were able to significantly (P < 0.05) reduce the blood glucose level of the diabetic rats at varying degrees compared to the diabetic untreated animals. Photomicrograph of the pancreas revealed that the crude extract and fractions reduced degenerative changes in the beta cells of islet of Langerhans at varying degrees compared to the diabetic untreated animals. At 400 mg/kg/day, the n-hexane fraction showed the least protective effect on the islets cells. IR spectroscopic analysis revealed that carbonyl groups are the major functional groups present in the tested samples. GC-MS analysis of the ethylacetate and n-hexane fractions revealed that the compounds contained in these fractions are non-polar, long chain fatty acids and esters, few alcohols, long chain saturated alkanes and unsaturated alkenes. This study has shown that the various fractions of Eleusine coracana can significantly reduce blood glucose level in diabetic rats and these fractions contain compounds which may attribute to their antidiabetic effect

Cymbopogon citratus (lemongrass) is well known for its medicinal and therapeutic activity which is mainly due to its essential oil, which has been established in previous studies to exhibit antioxidant, and sun-protective properties. In addition, the previous study has already determined its phytochemical composition (via GC-MS). This study serves as a continuation of previous work, focusing on the physicochemical characterization of lemongrass essential oil and its formulation into a cream to explore its stability and potential skincare applications. Fresh lemongrass leaves were subjected to hydrodistillation using a Clevenger-like apparatus to extract the essential oil. The physicochemical properties of the oil were analyzed, including specific gravity, acid value, saponification value, refractive index, iodine value, color, and taste. The extracted oil was then formulated into an oil-in water (O/W) emulsion cream, and its stability, pH, viscosity, spreadability, and irritation potential were evaluated. The yield of the extracted essential oil was 0.64%. Physicochemical analysis indicates a specific gravity of 0.8713, acid value of 5.0 mg KOH/g, saponification value of 170 mg KOH/g, refractive index of 1.4818, iodine value of 60 g I₂/100 g, and a pale yellow color with a bitter, spicy taste. The formulated cream exhibited good visual stability, spreadability, and a neutral pH, with the 1% essential oil concentration showing the best compatibility with the skin. These findings validate the potential of Cymbopogon citratus essential oil as a natural sun screen ingredient for skincare formulations, particularly for its stability and suitability in cream-based products. Further studies on the long-term stability and enhanced formulation characteristics are recommended.