<i>In Vitro</i> Anti-Diabetic Activities and Phytochemical Analysis of Bioactive Fractions Present in <i>Meriandra dianthera, Aloe camperi</i> and a Polyherb

Abstract

This paper reports the in vitro anti-diabetic profile of certain medicinal plants traditionally used in Eritrea for the management of type 2 diabetes. The crude methanolic extracts and fractions of Meriandra dianthera, Aloe camperi, a Polyherb and their fractions were investigated. The in vitro screening of the crude extracts has generally elicited a dose dependent α-glucosidase and α-amylase inhibition activities. M. dianthera displayed the highest α-glucosidase inhibitory activity (IC 50 : 0.074 ± 0.032 mg/mL) at the highest concentration tested (0.800 mg/mL) relative to A. camperi, the Polyherb and Acarbose (IC 50 : 0.37 ± 0.052, 0.56 ± 0.024 and 0.55 ± 0.029 respectively). The α-glucosidase inhibition activities of A. camperi and M. dianthera, except for the Polyherb and Acarbose, were significantly different (P < 0.05) at various ranges of concentrations (0.025 -0.800 mg/mL). The percentage α-amylase inhibitions of M. dianthera, A. camperi, the Polyherb and Acarbose, at the highest concentrations (0.800 mg/mL), were 78.3%, 15.9%, 16.4%, and 82.9% respectively. A. camperi and the Polyherb displayed lower α-amylase inhibitory activities (IC 50 :1.72 ± 0.06 and 2.57 ± 0.07 mg/mL respectively) compared to Acarbose and M. dianthera (IC 50 : 0.31 ± 0.01 and 0.43 ± 0.02 mg/mL respectively). For the α-amylase inhibition activity, even at lower concentrations (0.025 mg/mL), there were statistically significant differences (P < 0.01) among the values generated for all the extracts. The in vitro anti-diabetic screening of the fractions, at 0.800 mg/ml, displayed characteristic enzyme inhibition activities.How to cite this paper: Sium, M., Kareru, P., Kiage-Mokua, B., Sood, K., Langley, J. 534Generally, the non-polar fractions showed higher enzyme inhibitory activities compared to the polar fractions. The most bioactive non-polar fractions, thus, were subjected to GC-MS analysis and presented various essential oils, fatty acid methyl esters (FAMEs) and benzoic acid derivatives in those plants.

Analysis of Chemical Composition and Assessment of Cytotoxic, Antimicrobial, and Antioxidant Activities of the Essential Oil of Meriandra dianthera Growing in Saudi Arabia

“…This is, to some extent, in agreement with an earlier study on the essential oil of M. dianthera grown in Yemen [4], which revealed the presence of only 12 compounds, and among them, camphor (43.6%) and 1,8 cineole (10.7%) were the major constituents. Our results are partly in agreement with a recent study done by Sium and co-workers in 2017 [8] who investigated the chemical content and the anti-diabetic activity of the methanol extract of M. dianthera grown in Eritrea and revealed a predominance of camphor, borneol, α-terpineol, and β-eudesmol as well as a significant anti-diabetic activity through α-glucosidase and α-amylase inhibition activities [8]. Unlike our results, palmitic acid methyl ester and α-linolenic acid methyl ester were characterized in M. dianthera by Sium and co-workers in 2017 [8].…”

“…The infusion of the plant is indicated for wounds as an antiseptic agent and as a remedy for urinary tract infections [5,6]. In Eritrean traditional medicine, M. dianthera is taken for hypertension, malaria, hepatitis, infections, and diabetes [7,8]. Former works on the leaves and the roots of this plant showed the presence of volatile oil, sesquiterpenoids, abietane diterpenoids, triterpenoids, and flavonoids [4,9,10,11].…”

In vitro α-Amylase and α-Glucosidase inhibitory activity of extracts of Feronia elephantum fruit and Paspalum scrobiculatum Grains.

“…Where A c is the absorbance of the control and A " ontrol" " s is the absorbance of the sample The concentration ample" . of the extracts required to inhibit 50% of α-amylase and αglucosidase activity under the assay conditions was defined as the IC value (Sium et al 2017). IC was calculated by 50 50…”

Antimalarial Activity of Meriandra dianthera Leaf Extracts in Plasmodium berghei-Infected Mice

“…ese essential oils [37][38][39] and fatty acid esters were reported to demonstrate significant in vitro and in vivo antiplasmodial activities [40][41][42]. Besides the antiplasmodial effect, both the essential oils and fatty acid methyl esters were reported to exhibit in vitro α-glucosidase and α-amylase inhibitory effects [13,15]. Also, the essential oils exerted anticancer, antimicrobial, and antioxidant property [13], and the fatty acids exhibited in vivo antidiabetic activity in rodent models [14].…”

“…Moreover, an essential oil extracted from M. dianthera aerial parts was reported to demonstrate promising anticancer effect against all cancer cell lines (IC 50 values ranged from 83.6 to 91.2 μg/ mL) and considerable antibacterial, antifungal, and antioxidant properties [13]. Furthermore, methanolic leaves extract of M. dianthera showed significant in vitro α-amylase and α-glucosidase inhibitory activities as well as in vivo antidiabetic effect in alloxan-induced diabetic rats [14,15]. As there is no scientific work that verifies the traditional antimalarial claim of M. dianthera, the present study was aimed to investigate the in vivo antimalarial activity of M. dianthera leaf extract using mice model.…”