Gloria Aderonke Otunola

Comparative analysis of the chemical composition of three spices – Allium sativum L. Zingiber officinale Rosc. and Capsicum frutescens L. commonly consumed in Nigeria

The beneficial health effects of spices against common chronic systemic diseases have been well documented. Comparative study of the proximate, mineral and phytochemical components of three spices namely garlic ( Allium sativum L. ), ginger ( Zingiber officinale Rosc.) and pepper ( Capsicum frutescens L.) were investigated. Analysis of the proximate composition revealed that the spices had considerable carbohydrate and crude protein content, but low ash, fibre, moisture and fat except pepper which has high crude fat content. The spices were also characterized by the presence of mineral elements such as calcium, iron, potassium, phosphorus, sodium, magnesium, copper and zinc which are very important to human nutrition. Phytochemical screening indicated that these spices are also rich in phytonutrients including alkaloid, tannin, carotenoids, saponin and flavonoids. The spices had low concentrations of steroids and cardenolides. Overall, the findings indicate that the spices are good sources of nutrients, mineral elements and phytochemicals which could be exploited as great potentials for drugs and/or nutritional supplements. Key words : Comparative, nutritional, supplements, spices.

Characterization, antibacterial and antioxidant properties of silver nanoparticles synthesized from aqueous extracts of Allium sativum, Zingiber officinale, and Capsicum frutescens

Background: Herbal drug delivery is limited by poor solubility and bioavailability which can be overcome with suitable nanomaterials that will enhance their pharmacokinetics and performance. Objective: This study aimed to analyze the synthesis, characterization, and biological activities of silver nanoparticles (AgNPs) from three spices. Materials and Methods: AgNPs were prepared using 0.1 M silver nitrate and aqueous extracts of Allium sativum L. (garlic), Zingiber officinale Rosc. (ginger), and Capsicum frutescens L. (cayenne pepper). The AgNPs were characterized using ultraviolet-visible (UV-Vis) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray, X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. Results: The AgNPs were formed within an hour of the reaction and showed maximum UV-Vis absorption in the 375–480 nm range. SEM and TEM revealed well-dispersed spherical particles with little agglomeration, average sizes of 3–6 nm, 3–22 nm, and 3–18 nm for garlic, ginger, and cayenne pepper, respectively. FTIR showed that amine, protein, phenolic, aromatic, and alkynes groups contributed to AgNP synthesis and XRD confirmed their crystalline and face-centered cubic nature. Antibacterial action of the AgNPs was in the following order: ginger (minimum inhibitory concentration [MIC] <25 μg/mL) > garlic> cayenne pepper (MIC 125 μg/mL). Antioxidant action showed cayenne pepper > ginger > garlic (inhibitory concentration 50% [IC50]: 40, 240, and 250 μg/mL, respectively) against 2,2-Azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) and garlic > cayenne pepper > ginger (IC50: <31.25, 40, and 120 μg/mL, respectively) against 1,1-diphenyl-2-picrylhydrazyl. Conclusion: Optimization of this green synthesis would support the production of AgNPs with great therapeutic potentials. Abbreviations used: AgNPs: Silver nanoparticles; UV-Vis: ultraviolet-visible; SEM: Scanning electron microscopy; TEM: Transmission electron microscopy; EDX: Energy dispersive X-ray; XRD: X-ray diffraction; FTIR: Fourier transform infrared; GaNPs: Garlic nanoparticles; GiNPs: Ginger nanoparticles; C.PeNPs: Cayenne pepper nanoparticles; FCC: Face centred cubic; SPR: Surface Plasmon resonance; ABTS-2: 2-Azino-bis (3-ethylbenzthiazoline-6-sulfonic acid); DPPH-1: 1-diphenyl-2-picrylhydrazyl.

Antidiabetic effect of combined spices of Allium sativum, Zingiber officinale and Capsicum frutescens in alloxan-induced diabetic rats

Allium sativum (garlic), Zingiber officinale (ginger) and Capsicum frutescens (cayenne pepper) are common dietary spices also traditionally used in the treatment of various diseases including diabetes mellitus. The antidiabetic activity of each individual spice is well documented, but their effect when combined is unknown. Polyherbalism is of current interest because polyherbal formulations enhance therapeutic action and reduce the concentrations of single herbs, thereby reducing adverse events. This study evaluated the hypoglycaemic activity of aqueous extract of combined garlic, ginger and cayenne pepper (GGCP) at different doses in alloxan-induced diabetic rats. Diabetic rats were treated with GGCP at 200 mg and 500 mg/kg body weight/day, or glibenclamide (5 mg/kg body weight/day) for 7 days. GGCP extract significantly (p < 0.05) lowered the elevated fasting blood glucose, lipid and haematological indices. The mixture markedly attenuated cellular toxicity, and reduced tubular degeneration and necrosis in the kidney, fatty degeneration and necrosis in the liver and pancreatic hyperplasia in diabetic rats. These effects were more pronounced at 500 mg/kg and equipotent with glibenclamide, suggesting that in addition to its hypoglycaemic activity, GGCP protects the blood, kidney, liver and pancreas against diabetic injury. This is the first pilot study to evaluate a possible role for this spice mixture in the treatment of diabetes.

Lifestyle factors and co-morbidities associated with obesity and overweight in Nkonkobe Municipality of the Eastern Cape, South Africa

BackgroundObesity is a global epidemic that affects 500 million people worldwide and is predicted to increase to one billion people by 2030. The prevalence of obesity is increasing across populations in South Africa. However, questions still remain surrounding the predisposing factors and obesity-related health problems especially in the rural areas. This study evaluated several lifestyle factors such as dietary habits, physical activity, smoking, alcohol intake, co-morbidities and their association with the prevalence of obesity and overweight in Nkonkobe Municipality of the Eastern Cape.MethodsA cross-sectional, population-based survey was conducted among 118 residents in four rural/sub-urban townships of the study area. Measurements including weight, height, body mass index (BMI), physical activity and dietary habits were determined using a validated questionnaire.ResultsThe overall prevalence of obesity and overweight was 38 and 19%, respectively. The highest prevalence of obesity (70%) was observed among those who do not undertake any physical activity. Close to half (48.48%) of the respondents who eat fast foods always were obese, and 30.30% were overweight; when combined, the prevalence for obesity is 78.78%. A negative association with obesity was observed among regular smokers (26.92%) and consumers of alcohol (4.00%). Arthritis, hypertension and tuberculosis were co-morbidities significantly (P < 0.05) associated with obesity in the study area.ConclusionsThe findings of this study reveal that lack of physical activity, overindulgence on fast and fried foods, low fruit and vegetable consumption as well as arthritis, hypertension and tuberculosis were significant risk factors of obesity in Nkonkobe Municipality.

Evaluation of acute and subacute toxicity of whole-plant aqueous extract of Vernonia mespilifolia Less. in Wistar rats

OBJECTIVE This study investigated the acute and subacute toxicity of whole-plant aqueous extract of Vernonia mespilifolia Less. (AEVM) in rats for evaluating its safety profile. METHODS AEVM for the acute (2000 and 5000 mg/kg) and subacute (200, 400 and 600 mg/kg) toxicity studies was administered orally to rats according the guidelines 425 and 407 of Organization for Economic Cooperation and Development, respectively. Food and water intake as well as body and organ weight of animals were recorded. Signs of toxicity were assessed, and hematological, biochemical and histopathological analyses were performed. RESULTS In the acute toxicity study, a single dose of the aqueous extract at 2000 or 5000 mg/kg caused no mortality in the animals, suggesting that the median lethal dose is greater than 5000 mg/kg. In the subacute toxicity study, administration of the extract for 28 d, at all doses, caused no significant changes in the body weights or organ weights of rats in the treated groups when compared with the control group. In addition, hematological and biochemical parameters also revealed no toxic effects of the extract on rats. Histological sections of the heart, liver and kidney from test animals showed no signs of degeneration. CONCLUSION These results showed that AEVM at dosage levels up to 600 mg/kg is nontoxic and could also offer protection on some body tissues. AEVM could, therefore, be considered safe.

Acute and subacute toxicity of aqueous extract of the tuber of Kedrostis africana (L.) Cogn in Wistar rats

Abstract Kedrostis africana (L.) Cogn (Cucurbitaceae) is used in South African traditional medicine and pharmacopoeia as an emetic, purgative and diuretic, and it is used against dropsy in the management of obesity. Aim of the study In this study, acute and subacute toxicity of aqueous extract of K. africanatuber was evaluated in male and female Wistar rats in order to assess its safety profile. Materials and methods In acute toxicity, the effects of a single oral dose (2,000 and 5,000 mg/kg) of aqueous extract was determined in both sexes. General behavior, adverse effects and mortality were determined for 3 h and then periodically for 14 days. The subchronic toxicity test was performed in rats. The effects of the extract in daily single oral administration at the doses of 200, 400 and 600 mg/kg for 28 days were determined. Food and water intakes were monitored daily while body weight was monitored on a weekly bases. Hematological, biochemical and organ parameters were determined at the end of the 28-day administration. Results In the acute study, a single administration of the aqueous extract at the doses of 2,000 and 5,000 mg/kg did not induce mortality. Thus, the LD50 of the aqueous extract of K. africana (AEKA) has been estimated to be higher than 5,000 mg/kg. In the subchronic study, daily oral administration of the AEKA did not result in death of the rats or significant changes in hematological or biochemical parameters at the highest dose of 600 mg/kg. No alteration was observed in body weight, food and water intake. Liver, kidney and heart histopathology did not reveal morphological alteration. Conclusions The results showed that the aqueous tuber extract of K. africana did not cause any death, nor did it cause abnormalities in necropsy and histopathology findings. There were no acute or subchronic toxicity observed, and this indicates that the plant extract could be considered safe for oral medication.

In vitro α-amylase, α-glucosidase, lipase inhibitory and cytotoxic activities of tuber extracts of Kedrostis africana (L.) Cogn

Kedrostis africana, is a tuberous plant commonly used by traditional healers in the Eastern Cape Province of South Africa for the management of obesity. The aim of this study was to investigate the antiobesity and cytotoxic effects of Kedrostis africana extracts in vitro The α-amylase, α-glucosidase and lipase inhibitory activities of aqueous and ethanol extracts of Kedrostis africana tuber were investigated while the cytotoxic effects of these extracts were analyzed using Hoechst 33342 and propidium iodide (PI) dual staining in combination with Molecular Devices ImageXpress Micro XLS Widefield microscope for high content analysis on human cervical (HeLa) cell line. The ethanol extract exhibited the strongest inhibitory effect on pancreatic lipase (IC50 = 381.86 μg/ml) and on α-glucosidase (IC50 = 157.99 μg/mL) while the aqueous extract has strongest α-amylase (IC50 = 439.45 μg/ml). Both tuber extracts were found nontoxic at tested concentrations on HeLa cell lines as confirmed by the Hoechst 33342 and propidium iodide dual staining respectively. This study revealed that both the aqueous and ethanol tuber extract of K. africana exerts a certain degree of inhibitory effect on α-amylase, α-glucosidase and lipase and were also nontoxic to HeLa cell line at tested concentrations.

Evaluation of the physicochemical, proximate, and sensory properties of moinmoin from blends of cowpea and water yam flour

Abstract Moinmoin is a steamed cowpea seed‐based pudding native to Nigeria. This study evaluated the physicochemical, proximate, and sensory properties of moinmoin from a blend of cowpea and water yam flours. The pudding was prepared by varying the proportion of cowpea to water yam flour (CWYP). The blends were in the ratio 75:25% (CWYP1), 50:50% (CWYP2), and 100:0% cowpea flour (CPP) which served as the control. Physicochemical evaluation indicated that the products will have good keeping quality and reconstitute easily. Protein content was 26.90%, 20.10%, and 17.60% for CPP, CWYP1 and CWYP2, respectively, and the presence of water yam significantly (p < .05) increased the crude fiber, ash, and carbohydrate contents of the cowpea/water yam products relative to the control. Pasting properties revealed that regardless of the proportion of water yam in the mixture, the moinmoin samples cooked at approximately the same time; and sensory evaluation showed that CWYP1 was best preferred in terms of taste, flavor, color, and overall acceptability. These findings suggest that the cowpea/water yam pudding can meet the nutritional demands of a meal and that the 75%–25% cowpea/water yam mixture was the most acceptable. The study contributes to the knowledge nutritious products with desirable organoleptic qualities from a blend of cowpea and water yam flour, allowing for up to 50% water yam substitution. It also provides an alternative way of utilizing water yam thus preventing wastage during peak production and ensuring food and nutritional security because of the balanced products obtained.

In vitro antibacterial, antioxidant and toxicity profile of silver nanoparticles green-synthesized and characterized from aqueous extract of a spice blend formulation

ABSTRACT Here we report the synthesis, characterization and biological properties of silver nanoparticles (AgNPs) using the extract from a spice blend. AgNPs were prepared using 0.1 mmol/L AgNO3 solution and aqueous extract from a spice blend of garlic, ginger and cayenne pepper. The nanoparticles were characterized using ultraviolet–visible (UV-vis) spectroscopy, scanning and transmission electron microscopy (SEM and TEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The AgNPs formed within an hour of the reaction with colour change from yellow to dark brown and maximum absorbance at 420 nm in the UV-vis spectrum. SEM revealed well dispersed particles with little agglomeration, and the presence of elemental silver was confirmed by EDX. TEM confirmed the formation of poly-dispersed, spherical-shaped NPs with size range of 6–28 nm. FTIR showed that amine, protein, phenolic, aromatic and alkyne groups contributed to AgNPs synthesis, and XRD confirmed their crystalline and face-centred cubic nature. Both Gram-negative and Gram-positive bacteria were susceptible to the spice blend AgNPs with MIC of 0.0625 at 62.5 µg/mL. The AgNPs exhibited greater inhibition on DPPH radical with IC50 < 31.25 µg/mL, while it was 68.75 µg/mL for ABTS. The nanoparticles were not toxic against MDA-MB-231 breast cancer cell lines. These spice blend nanoparticles would support the production of AgNPs with significantly enhanced pharmacokinetic properties and greatly improved therapeutic performance.