Open Access Minireview Article

Mechanisms and Antidiabetic Compounds of Balanites aegyptiaca delile Plant: A Mini-review

D. H. Mhya, K. M. Anigo, I. A. Umar, J. O. Alegbejo

South Asian Research Journal of Natural Products, Page 1-9

Balanites aegyptiaca has been reported to exert significant antidiabetic activity. It was reported to lowered blood glucose levels by different mechanisms where various active compounds were identified. In this review, bioactive compounds and likely mechanisms of action were highlighted. The review showed that different mechanisms such as oxygen radical scavenging activity, increased insulin secretion, and enhanced regeneration of beta cell of the pancreas was reported to explain antidiabetic effect of the plant. The plant also exerted alpha amylase inhibitory activity, insulinomimetic effect and enhanced glucose uptake by tissues. Compounds like steroidal saponins, simple phenolics and flavonoids are the likely active molecules reported. In conclusion, Balanites aegyptiaca has potential chemicals which exerted different antidiabetic mechanisms and if properly harnessed may lead to the discovering of new substance which could better serve in the management of diabetes mellitus.

Open Access Original Research Article

Antibacterial Potentiality and Brine Shrimp Lethality Bioassay of the Methanol Extract of Trema orientalis Leaves

Md. Mashiar Rahman, Nachiketa Bairagi, Md. Masnoon Kabir, Mohammad Jashim Uddin

South Asian Research Journal of Natural Products, Page 1-9

Aim: The aim of this study was to evaluate the antibacterial and cytotoxic activities of methanol extract of Trema orientalis leaves.

Materials and Methods: Antibacterial activity of Trema orientalis leaves was tested against two Gram-positive and seven Gram-negative bacteria by disc diffusion assay. The liquid microdilution assay was used for the determination of the minimum inhibitory concentration (MIC). The brine shrimp lethality bioassay analyzed the cytotoxic activity of methanol extract of Trema orientalis leaves.

Results: The methanol extract exhibited potent antibacterial activity with the zone of inhibition ranging from 9± 0.81 to 14±0.81 mm against both the tested Gram-positive and all tested Gram-negative bacteria except Pseudomonas denitrificans and Xanthomonas campestris. Comparatively, higher antibacterial activity was found against Gram-negative bacteria in case of Shigella dysenteriae and Salmonella typhi which showed 14±0.81 mm and 13±0.81mm zones of inhibition respectively. Salmonella typhi showed resistance against reference antibiotics (Tetracycline, Erythromycin, Gentamicin and Ciprofloxacin) but methanol extract of leaves exhibited potent antibacterial activity against Salmonella typhi. The MIC values for tested Gram-positive bacteria were 10 mg/mL while for Gram-negative bacteria were ranged from 1.25 to 20 mg/mL. The methanol extract of Trema orientalis leaves showed very low cytotoxicity (LC50, 170.215 μg/mL) in comparison with the standard vincristine sulphate having LC50 value 2.477 µg/mL.

Conclusion: The results suggest that the methanol extract of Trema orientalis leaves has potent antibacterial activity with minimum cytotoxicity and could lead to the development of novel broad-spectrum antibacterial agent.

Open Access Original Research Article

Effect of Processing Unripe Plantain (Musa paradisiaca) Extracts on Some Biochemical Parameters in Alloxan-Induced Wistar Rats

C. D. Luka, J. C. Oyeocha, M. K. Kwarpo, G. Istifanus

South Asian Research Journal of Natural Products, Page 1-9

Unripe plantain is used for management of diabetes mellitus in Nigeria, the possible effect of its methods of processing on some biochemical parameters has not been investigated. The objective of this study is to determine the effect of methods of processing unripe plantain on blood glucose, Total Cholesterol, Triglyceride, HDL, LDL, serum Alanine aminotransferase (ALT), Aspartate aminotransferase (AST), Alanine Phosphatase (ALP), total protein, albumin, creatinine, uric acid and urea levels in alloxan-induced diabetic rat models. Twenty male albino Wistar rats were used and were divided into 5 groups of 4 rats each.  Group 1 (normal control) received standard rat feeds; group 2 (diabetic control) received standard rat feeds; groups 3,4 and 5 received boiled, roasted and dried unripe plantain pellets respectively. In the result, a significant (P<0.05) reduced blood glucose levels were seen for those experimental animals given dried, boiled and roasted extracts respectively. Triacylglycerol levels were significantly decreased (p<0.05) for those diabetic rats administered dried, boiled and roasted extracts respectively. The Total cholesterol levels were significantly decreased (p<0.05) for those administered dried, roasted and boiled extracts respectively. The LDL-cholesterol levels were also significantly decreased (p<0.05) for those treated with dried, roasted and boiled extracts respectively. The HDL-cholesterol were significantly increased for the diabetic administered dried extract, roasted extract and a significant decrease for those administered boiled extract. There were significant increase (p<0.05) in the levels of serum ALT, AST and ALP in the diabetic control group compared to the normal control are observed. On administration of unripe plantain, the values of these enzymes significantly decreased (p<0.05). The boiled extract showed a greater decrease in the level of ALT and ALP whereas the dried extract showed a greater decrease in the level of AST. There were also increase in the level of urea and uric acid in the diabetic control compared to the normal control group is observed. However the dried extract showed a greater decrease in the levels of both urea and uric acid. The creatinine level is seen to increase in the diabetic control group when compared to the normal control group and showed greater increase on administration of unripe plantain, for the group fed with roasted extract having the highest level of creatinine. 

Open Access Original Research Article

Substantiation of the Rational Drying Conditions for the Herbal Raw Material of Goutweed (Aegopodium podagraria L.) Aerial Part

N. I. Pogozhikh, O. V. Tovchiga, V. V. Evlash, S. I. Stepanova, O. O. Koyro

South Asian Research Journal of Natural Products, Page 1-11

Aims: The present study aims to substantiate the rational conditions for the industrial drying of goutweed (Aegopodium podagraria L.) aerial part enabling its use in the pharmaceutical and food industries.

Methodology: The traditionally used shade drying (18–22°C for 3–5 days, sample 1) was compared with the industrial drying with the help of the original equipment presupposing mixed heat transfer (60–70°C for 90 min or 50°C for 120 min, sample 2 and sample 3, respectively). The moisture content (loss on drying) was determined, hydroxycinnamic acids and flavonoids were identified by HPLC, and the quantitative content of hydroxycinnamic acids was measured using direct spectrophotometry and spectrophotometry of the coloured complexes.

Results: It has been shown that the moisture content is comparable in all samples and there are no significant changes in the spectrum of biologically active substances identified by HPLC in the samples 2 and 3. The quantitative content of hydroxycinnamic acids is decreased in these samples that may be associated with the activation of polyphenol oxidase at the beginning of drying. Thus, the industrial drying methods do not cause principal changes in the spectrum of goutweed active substances and are advantageous in shortening the drying time. Nevertheless, the drying conditions modifications (presumably, an increase in the temperature at the beginning of drying) are needed for better preservation of hydroxycinnamic acids in goutweed raw material. The further studies will address these issues, since the shade drying, despite the possibility of obtaining of the final product with satisfactory quality (that is consistent with the previous data obtained under the laboratory conditions), is unacceptable for use in the manufacturing facilities.

Open Access Original Research Article

Optimizing the Extraction of Bioactive Compounds from Leaves of Gymnema Lactiferum, an Edible Green Leafy Vegetable

K. D. P. P. Gunathilake, K. K. D. S. Ranaweera, H. P. V. Rupasinghe, R. M. T. R. K. Rathnayaka

South Asian Research Journal of Natural Products, Page 1-9

Gymnema lactiferum is a leafy vegetable which contains phenolics and carotenoids and also possesses many health benefits such as antidiabetic properties. Response surface methodology (RSM) has been used to optimize the extraction parameters for the recovery of total phenolic compounds and carotenoids from leaves of Gymnema lactiferum. Solvent concentration (30-100%), extraction temperature (30-60°C) and extraction time (30-90 min) were used as the independent variables. A three-factor inscribed central composite design (CCD) was used to identify the relationship existing between the response functions (total phenolics and carotenoids) and the process variables, as well as to determine those conditions that optimised the extraction process of total phenolics and carotenoids contents of the extracts. A second order polynomial model produced a satisfactory fitting of the experimental data with regard to total phenolics (R2 = 86.75%, p < 0.002) and carotenoid (R2 = 84.74, p < 0.017) contents. The optimum extraction conditions of ethanol concentration, extraction temperature and extraction time for phenolics, were 19.2%, 70.2°C and 98.2 min for phenolics and 100%, 70.20°C and 110.5 min for carotenoids. The experimental values for total phenolics were 4.01±0.74 mg gallic acid equivalent (GAE) g extract and 3.56±0.19 mg/g dry weight (DW) carotenoids and no significant difference (p < 0.05) was found between the experimental and predicted values of the extractable phenolics and carotenoids