In vitro α-glucosidase inhibitory activity of Tamarix nilotica shoot extracts and fractions

Abstract

α-glucosidase inhibitors represent an important class of type 2 antidiabetic drugs and they act by lowering postprandial hyperglycemia. Today, only three synthetic inhibitors exist on the market, and there is a need for novel, natural and more efficient molecules exhibiting this activity. In this study, we investigated the ability of Tamarix nilotica ethanolic and aqueous shoot extracts, as well as methanolic fractions prepared from aqueous crude extracts to inhibit α-glucosidase. Both, 50% ethanol and aqueous extracts inhibited α-glucosidase in a concentration-dependent manner, with IC50 values of 12.5 μg/mL and 24.8 μg/mL, respectively. Importantly, α-glucosidase inhibitory activity observed in the T. nilotica crude extracts was considerably higher than pure acarbose (IC50 = 151.1 μg/mL), the most highly prescribed α-glucosidase inhibitor on the market. When T. nilotica crude extracts were fractionated using methanol, enhanced α-glucosidase inhibitory activity was observed in general, with the highest observed α-glucosidase inhibitory activity in the 30% methanol fraction (IC50 = 5.21 μg/mL). Kinetic studies further revealed a competitive reversible mechanism of inhibition by the plant extract. The phytochemical profiles of 50% ethanol extracts, aqueous extracts, and the methanolic fractions were investigated and compared using a metabolomics approach. Statistical analysis revealed significant differences in the contents of the crude extracts and fractions and potentially identified the molecules that were most responsible for these observed variations. Higher α-glucosidase inhibitory activity was associated with an enrichment of terpenoids, fatty acids, and flavonoids. Among the identified molecules, active compounds with known α-glucosidase inhibitory activity were detected, including unsaturated fatty acids, triterpenoids, and flavonoid glycosides. These results put forward T. nilotica as a therapeutic plant for type 2 diabetes and a source of α-glucosidase inhibitors.

Metabolomics-Based Profiling via a Chemometric Approach to Investigate the Antidiabetic Property of Different Parts and Origins of Pistacia lentiscus L.

“…Compared to the previous studies in the literature, the fruit extracts (IC50 = 42 µg/mL) showed a greater inhibitory potency than did Sardinian P. lentiscus fruit aqueous extracts, with IC50 = 230 µg/mL [ 30 ].The inhibition percentages of α-glucosidase of the leaves and fruit extracts (49% and 13%, respectively) were comparable to the inhibition percentages of α-amylase of ethanolic leaf (55%) and fruit (54%) extracts [ 23 ].The activity of α-glucosidase inhibition has been tested in several other plants [ 65 , 66 , 67 ]. Plant extracts including Tamarix nilotica (IC50 = 33.3 µg/mL) [ 65 ], Tetracera scandens (IC50 = 3.4 µg/mL) [ 66 ] and Cosmos caudatus (IC50 = 39.1 µg/mL) [ 67 ] have shown promising α-glucosidase inhibition. These activities are comparable to those of acarbose and to the results found in the present study.…”

“…Previous work has established statistical models of the relationship between the phytochemical profiles obtained via LC-MS/MS and the inhibition of α-glucosidase by plant extracts [ 66 , 67 , 69 ]. The results of this work revealed that α-glucosidase-inhibitory activity was probably due to the presence of terpenoids, fatty acids, phenolic, flavonoids (epigallocatechin-3-O-gallate) and flavonoid glycosides (quercetin 3-O-glucoside) [ 65 , 67 ]. (-)-Epigallocatechin-3-O-gallate offers a promising hypoglycemic effect [ 65 , 70 ].…”

“…The results of this work revealed that α-glucosidase-inhibitory activity was probably due to the presence of terpenoids, fatty acids, phenolic, flavonoids (epigallocatechin-3-O-gallate) and flavonoid glycosides (quercetin 3-O-glucoside) [ 65 , 67 ]. (-)-Epigallocatechin-3-O-gallate offers a promising hypoglycemic effect [ 65 , 70 ].…”

Co-exposure to Polyethylene Fiber andSalmonella entericaTyphimurium Alters Microbiome and Metabolome ofin vitroChicken Cecal Mesocosms

“…Within this study, simulanoquinoline levels increased over the time course for +PE fiber + Salmonella , +PE powder + Salmonella and + Salmonella treatment groups (Figure 3a), suggesting that Salmonella produced this metabolite, stimulated production of it or induced the release of the molecule from the feed particles that were in the mesocosm. Daou et al (2022) reported detecting simulanoquinoline in abundance in the crude extracts of the shrub Tamarix nilotica (61). Given that the basal diet incorporated into the cecal mesocosms contains plant compounds, it is plausible that interactions among the PE fiber, S .…”

Fraksinasi Flavonoid Spirulina platensis dengan Metode Kromatografi Lapis Tipis dan Aktivitas Inhibisi Enzim α-Glukosidase

“…Lemahnya aktivitas penghambatan terhadap enzim α-glukosidase pada penelitian ini diduga karena bahan yang digunakan masih dalam bentuk ekstrak kasar/crude extract. Hal ini sesuai dengan Daou et al (2022) yang melaporkan bahwa aktivitas inhibisi enzim α-glukosidase oleh komponen ekstrak kasar Tamarix nilotica lebih lemah dari aktivitas inhibisi enzim α-glukosidase oleh komponen hasil fraksinasi, di mana nilai IC50 komponen esktrak kasar 24,8 μg/mL, sedangkan nilai IC50 komponen fraksi mencapai 5,21 μg/mL. Silva et al (2020) juga melaporkan bahwa komponen fraksinasi dari Mouriri elliptica Martius memiliki aktivitas penghambatan (IC50) enzim acetylcholinesterase dan α-amilase yang jauh lebih tinggi daripada aktivitas penghambataan oleh komponen ekstrak kasarnya.…”