Evaluation of In vitro Antidiabetic Potential of Thymus schimperi R. and Thymus vulgaris L.

Diabetes has become the most common metabolic disease worldwide. In particular, type 2 diabetes is the most commonly encountered type of diabetes, which is characterized by impaired insulin secretion and/or action. One of the effective methods to control diabetes is to inhibit the activity of α-amylase and α-glucosidase enzymes which are responsible for the breakdown of starch to more simple sugars, using plant products. This study evaluated the total phenolic (TPC), total flavonoid (TFC), and antidiabetic potential of Thymus schimperi and Thymus vulgaris via in vitro inhibition of α-amylase and α-glucosidase, using the hot water and aqueous: methanol (20:80, v/v) extracts. The α-amylase inhibitory potentials of the extracts were investigated through reducing sugars analysis using 3,5-dinitrosalicylic acid color reagent (DNSA) using starch solution as substrate. The α-glucosidase inhibition was determined by pre-incubating α-glucosidase with different concentrations of the extracts followed by the addition of p-nitrophenylglucopyranoside (pNPG). Aqueous: methanol (20:80, v/v) extract of T. schimperi contained highest TPC (46.01 ± 4.54 mg GAE/g dw) and TFC (14.72 ± 1.14 mg QE/g dw) also showed stronger α-amylase inhibition activity (IC50 = 0.33 ± 0.05 mg/mL) and the hot water extract exhibited stronger α-glucosidase inhibition (IC50 = 0.05 ± 0.01 mg/mL) capacity than that of T. vulgaris. The TPC and TFC were positively related (p < 0.05) with α-amylase inhibition activity but negatively correlated (p > 0.05) with α-glucosidase inhibitory activity. These results indicated that the inhibition of these enzymes can lead to lower postprandial blood glucose. Keywords: α-Amylase, Antidiabetic, Diabetes mellitus, α-Glucosidase, Thymus, Total phenolics DOI: 10.7176/JHMN/69-02 Publication date: December 31st 201

Effects of Bambara groundnut and butternut blend on proximate, mineral, beta-carotene and folic acid contents of sorghum flour

The refined sorghum flour (SF) used is limited in fiber and micronutrients because of bran removal during milling, and protein digestibility is poor due to kafrin crosslinking. In this research, the effects of Bambara groundnut (BG) (15%, 25%, 35%) and butternut (BU) powder (23%) blending on SF were investigated, using 100% SF as a control. The proximate, mineral, beta-carotene and folic acid compositions of the flour mix were determined. As the BG levels increased, the protein, fat, fiber, and ash contents increased significantly (p < 0.05), ranging between 8.62–14.19%, 2.36–3.38%, 1.37–3.04% and 0.87–2.19%, respectively. The iron, zinc, calcium and phosphorus contents in mg/100 g were 3.43–5.08, 2.96–3.74, 80.00–106.67 and 150.63–594.53, respectively. The beta-carotene (mg/100 g) and folic acid (μg/100 g) contents were < 0.01–0.63 and 0.75–1.42, respectively. The mineral, beta-carotene and folic acid contents of the flour mix varied significantly (p < 0.05) from the control. The pro-vitamin A beta-carotene content was improved in the blend flours with the addition of BU powder, whereas, in the control sample, it was not detected (<0.01 mg/100 g). With the 35% BG blend, increases of 37% protein, 45% crude fiber, 48% iron, 26% zinc, 133% calcium and 154% folic acid contents from the control were observed. The study showed food-to-food fortification of SF with BG flour and BU powder has the potential to combat malnutrition, and the public health challenges associated with deficiencies in bioactive fibers, proteins and micronutrients (pro-vitamin A carotenoids, folic acid and minerals)

Protein Quality of Amaranth Grains Cultivated in Ethiopia as Affected by Popping and Fermentation Complementary Food

Abstract The effect of popping and fermentation on protein quality of three different varieties of amaranth grains cultivated in Ethiopia was evaluated. Total lysine content of the grains was higher than that of commonly available cereals but close to that of legumes. Methionine and cysteine contents in the grains were also higher than that found in cereal and legume proteins. Percentage of total indispensable amino acids, excluding tryptophan, was 43% -49%, which was higher than WHO reference pattern (31%). Popping resulted in 36% and 37% reduction in total lysine and cysteine contents, respectively, whereas fermentation reduced cysteine, lysine and methionine contents by 16%, 20% and 20%, respectively. From the free amino acids, histidine was the major indispensable amino acid but threonine was not detected. During popping, all free amino acids, except threonine, were reduced. On the other hand, fermentation significantly increased (p &lt; 0.01) most amino acids except arginine, which was significantly decreased (p &lt; 0.01), and tyrosine and glutamic acid, for which no change was observed. Popping decreased in vitro protein digestibility (IVPD) by 8.3% -17.1% while fermentation increased IVPD by 4.8% -7.5%. Substitution of amaranth for wheat and/or maize during complementary food formulation could contribute much to the daily requirements of indispensable amino acids of young children

Rheology and botanical origin of Ethiopian monofloral honey

© 2016 Elsevier Ltd Rheology and botanical origin of Ethiopian monofloral honeys were investigated using harmonized method of melissopalynology and HAAKE VT 500 over a temperature range of 25–45 °C, respectively. The percent dominance of monofloral honeys ranged from 59.8% (Croton macrostachyus) to 90.3% (Schefflera abyssinica). Botanical origin and geographical location of honeys were categorized on principal component analysis (PCA) of pollen data. The PCA graph showed that honeys were divided into two separate groups or three sub groups, based on their close appearance in the plot. The highest viscosity value was observed in Eucalyptus globulus honey and the lowest in Vernonia amygdalina. Shear stress versus shear rate linearity indicated that all the monofloral honeys exhibited Newtonian behavior. The effect of temperature on the viscosity of honey followed the Arrhenius relationship. The activation energy ranged from 60,042.05 (Eucalyptus globulus) to 9858.741 kJ/mol (Vernonia amygdalina). Viscosity of honey was found to be time independent

Indigenous Ethiopian okra (Abelmoschus esculentus) mucilage: A novel ingredient with functional and antioxidant properties

Functional and antioxidant properties of mucilage extracted from the pods of eight okra accessions grown in Benishangul‐Gumuz region, Western Ethiopia, were evaluated. This study had shown that the mucilage contents of the pods of eight okra accessions ranged from 1.25 to 3.45 g/100 g. Functional properties of the mucilage of okra pods varied significantly (p &lt; .05) and had respective ranges of bulk density of 0.58–0.64 g/ml; water absorption capacity of 2.45–4.60 ml/g; oil absorption capacity of 0.02–3.64 ml/g; emulsifying capacity of 42.22%–74.45%; emulsion stability of 42.22%–74.45%; foaming capacity of 50.51%–62.50%, and foam stability of 36.04%–54.35%. Total phenolic and flavonoid contents of the mucilage of the pods of okra accessions ranged from 4.66 to 49.93 mg GAE/g and 8.18–18.72 mg CE/g, respectively. The effective concentration (EC50) values (mg/ml) of mucilage of okra pods varied from 3.15 to 6.60 and 1.10 to 1.85 for DPPH scavenging and metal‐chelating activity, respectively. The study revealed that the mucilage of the pods of okra accessions was found to exhibit good functional properties and can offer a great potential in various food systems. Particularly, mucilage of the pods from OPA#5 and OPA#7 had desirable water and oil absorption capacities, whereas the mucilage of accession OPA#1 and OPA#6 had high emulsifying and foaming properties. The results also demonstrated that okra pod mucilage had potential sources of natural antioxidant

Enzyme activity, amino acid profiles and hydroxymethylfurfural content in Ethiopian monofloral honey

© 2017, Association of Food Scientists & Technologists (India). The enzymes activity, hydroxymethylfurfural (HMF) and amino acids in honeys are relatively low. However, they play very significant role for honey quality. In this study, enzymes, amino acids and HMF contents of Ethiopian monofloral honeys were investigated. Diastase, invertase and HMF were analyzed based on the Harmonized International Honey Commission method and amino acids using amino acids analyzer (HPLC). Diastase activity ranged from 3.91 ± 0.730 (Schefflera abyssinica) to 13.6 ± 2.30 [Becium grandiflorum (L: Lalibella)]; invertase 36.5 ± 1.93 (Leucas abyssinica) to 4.85 ± 2.36 (Schefflera abyssinica); and HMF 0 ± 0 (Hypoestes and Leucas abyssinica) to 3.37 ± 1.73 (Croton macrostachyus). Significant variations were observed among Schefflera abyssinica honeys in diastase content, despite being from the same botanical origin. Significant variations were also observed among Becium grandiflorum honeys in invertase and diastase contents. Bees’ geographical race and location affected enzymes activities. Lower level of enzymes could be an intrinsic characteristic of Ethiopian honey. Thus, enzymes activity alone cannot be a worthwhile indicator of quality for Ethiopian honey; besides diastase and invertase activity, the quality control of Ethiopian honeys should be supported by HMF parameters

Plant-based traditional foods and beverages of Gumare Village, Botswana

Abstract The consumption of traditional and indigenous foods and beverages varies across different ethnic communities and is often influenced by geographical location. However, the diversity of edible plants is rapidly declining due to climate change, leading to a loss of knowledge about useful plants used by different communities before the plant itself becomes extinct. This research investigated the edible plant types and investigated the processing steps of plant-based traditional foods/dishes and beverages of Gumare village, located in the catchment area of the Okavango Delta in the northwest of Botswana. Questionnaire interviews and focus group discussions (FGD) were used to collect data. The study identified 52 wild and 19 domesticated edible plants used in the preparation of traditional foods/dishes and beverages of Gumare village. Maize, sorghum, millets, beans, melon, watermelon, pumpkin, bottle gourd and sweet potato are widely used domesticated crops. The wild edible plants are either directly used after minor processing or as recipes in traditional dishes and/or as an inoculum in the fermentation, as a substrate in traditional beverages and some as medicinal plants. However, some taboos and food safety challenges were observed in the use of certain plants. The study highlighted a decline in the use of traditional foods/dishes and beverages, particularly among the young generation. The youth indicated that they have a low interest in gathering traditional foods and beverages due to the time-consuming nature during harvesting and the labour-intensive processing. In addition, they indicated the dangers of attacks by wild animals from veld by reptiles (for example snakes and pythons) and alligators (crocodiles) from rivers during the harvesting of raw materials used in traditional foods and dishes. For the communities, the diverse edible wild plants documented are a source of nutrients and bioactive compounds such as dietary fibers, phenolics, terpenes, essential oils, carotenoids, and alkaloids that help to combat malnutrition and for use as traditional medicines to support health and wellness. In conclusion, the significant diversity of wild edible plants and domesticated crops in Gumare village, likely due to its location in the catchment area of the Okavango Delta, plays a crucial role in diet diversification and can contribute to food and nutrition security. However, for most wild edible plants of Botswana, information on their nutrient and bioactive compounds are still limited. This study provides baseline information for further chemical investigation and development of resources in the formulation of functional foods and nutraceuticals. Graphical Abstrac

Sugar profile and physicochemical properties of Ethiopian monofloral honey

© 2017 Taylor & Francis Group, LLC. Three hundred twenty honey samples were collected from Ethiopia, and categorized into nine monofloral honeys using melissopalynology. Theses monofloral honeys were investigated for their sugar profile, physicochemical properties, and quality of honeys. Sugars (fructose, glucose, sucrose, maltose, turanose, and isomaltose) were identified using high-performance liquid chromatography and physicochemical properties (moisture, water activity, pH, acidity, ash, minerals, conductivity, colour) using the Harmonized Method of the International Honey Commission. Moisture and water activity showed a strong regression coefficient (r2 = 0.92). Moisture content alone did not sufficiently describe the quality of honey during storage and processing