GC–MS based metabolite profiling and angiotensin I-converting enzyme inhibitory property of black tea extracts

Investigation of α-Glucosidase Inhibitory Metabolites from Tetracera scandens Leaves by GC–MS Metabolite Profiling and Docking Studies

“…This study demonstrated the significant α-glucosidase inhibitory potential of the It is noticeable that the peaks of the putative active metabolites that are common in both chromatograms are more intense in the methanol extract than in the water extract. Moreover, the peaks of the metabolites phytol (2), linoleic acid (3), α-linolenic acid (4), 1-monopalmitin (5), catechin (10), α-tocopherol (11), stigmasterol (12), β-sitosterol (13), 1-triacontanol (14), cycloartenol (15) and 24-methylenecycloartenol acetate (16) have disappeared completely from the chromatogram of the water extract. These qualitative and quantitative differences can explain the great difference observed in the α-glucosidase inhibitory activity of both extracts.…”

“…In such a case, the metabolites are introduced into the ionization chamber sequentially instead of concomitantly, enhancing the quality of the acquired mass spectral data (i.e., better sensitivity and reduced background noise) leading to better qualitative and quantitative results [10]. GC-MS-based metabolomics has been used for profiling of the active metabolites from Clinacanthus nutans [5], Cosmos caudatus [11], Camellia sinensis [12], Achras sapota [13], and from selected commercial essential oils [14]. Figure 1 summarizes the procedure followed in the aforementioned studies.…”

Using polyphenols as a relevant therapy to diabetes and its complications, a review

“…When comparing the inhibitory power of the components, oligomeric flavonoids thearubigin and theaflavin were shown to be more effective than their monomeric counterparts, a conclusion that is also shared by the works of Balasuriya and Rupasinghe (Nileeka Balasuriya and Rupasinghe 2011) and Actis-Goretta, Ottaviani, and Fraga (2006). Ray et al (2017) showed that catechin's inhibitory power is three times higher than epicatechin (ECat) but Actis-Goretta, Ottaviani, and Fraga (2006) found a far smaller difference that was not even statistically significant. Kirakosyan et al (2018) studied the inhibition potential of Montmorency cherry extract on several common therapeutic targets (enzymes) for diabetes, including ACE, and found that it had significant inhibitory power.…”

“…There are many studies on the potential of polyphenols to inhibit ACE, which evaluate several plants or preparations/extracts and, in some cases, their most abundant compounds (Nileeka Balasuriya and Rupasinghe 2011;Sakulnarmrat and Konczak 2012;Oboh et al 2012;Actis-Goretta, Ottaviani, and Fraga 2006;Ray et al 2017;Kirakosyan et al 2018;Adefegha and Oboh 2016;Adefegha et al 2017). Ray et al (2017) analyzed the inhibiting power of black tea preparations and some of their components on ACE. Of the four black teas tested, the decoctions (tea leaves boiled with water) had a more powerful inhibitory effect when compared with their corresponding infusions (tea leaves soaked in boiled water).…”

The Pharmacological Activity of Camellia sinensis (L.) Kuntze on Metabolic and Endocrine Disorders: A Systematic Review

“…In general, decoctions were more active than infusions and Nilgiri tea showed the highest inhibitory activity. Antihypertension properties are mainly attributed to thearubigin and theaflavin [56,57]. In another in vitro study, pretreatments with black tea extract (0.3-5 µg/mL) and theaflavin-3,3'-digallate (0.03-0.5 µg/mL) for 30 min improved endothelium dependent relaxations in homocysteine (endoplasmic reticulum stress inductor) treated cultured rat aortic endothelial cells [58].…”