Characterization, Hypoglycemic Activity, and Antioxidant Activity of Methanol Extracts From Amomum tsao-ko: in vitro and in vivo Studies

Abstract

The dried fruit of Amomum tsao-ko is well-known as a spice as well as a Chinese traditional herb. This study aimed to identify the bioactive constituents in the powder of methanol extract from Amomum tsao-ko (PMEAT) and to evaluate the hypoglycemic and antioxidant effects of PMEAT, in vitro and in vivo. We identified 36 phytochemicals in PMEAT by employing HPLC-MS/MS. PMEAT solution was found to have potent α-glucosidase-inhibiting activity (IC50, 0.145 mg/mL) in vitro, twice as strong as that of acarbose (IC50, 0.273 mg/mL). To investigate the hypoglycemic activity of PMEAT in vivo, we studied the impact of low-dose PMEAT (the addition of 100 mg/kg PMEAT to the mice diet) and high-dose PMEAT (200 mg/kg PMEAT addition) treatments in STZ-induced diabetic mice. After 6 weeks of intervention, significantly decreased fasting blood glucose (FBG) (p < 0.05), significantly decreased area under the curve (AUC) of the oral glucose tolerance test (p < 0.05), significantly decreased HOMA-IR (p < 0.05), and significantly increased HOMA-β (p < 0.05) were observed in the high-dose PMEAT group. Moreover, we performed an antioxidant activity experiment in vitro. The results showed that PMEAT had a strong ability to scavenge DPPH (IC50, 0.044 mg/mL) as well as ABTS free radicals (IC50, 0.040 mg/mL). In an animal experiment conducted on oxidative damage mice model which was induced by D-glucose and a high-fat diet, we observed significantly increased dismutase (SOD) (p < 0.01), glutathione (GSH) (p < 0.01), and glutathione peroxidase (GSH-Px) (p < 0.01) and significantly reduced malondialdehyde (MDA) and 8-ISO-prostaglandin-PGF2α (8-ISO-PGF2α), after treatment with PMEAT for 90 days. In conclusion, this study reveals the therapeutic potential of Amomum tsao-ko for the treatment of diabetes and helps us discover new antioxidant candidates from natural sources.

Insight into the phytochemical profile and antimicrobial activities of Amomum subulatum and Amomum xanthioides: an in vitro and in silico study

“…Leucine levels were significantly increased ( p < 0.05) in seeds of A. subulatum compared with the fruits of the same species. A comprehensive chemical investigation found that A. tsao-ko contained a variety of chemical components including protein and amino acids ( Xie et al., 2022 ). Among the amino acids, glutamine serves as a major amino donor for the synthesis of amino acids, nucleotides, and other nitrogen-containing compounds, in addition to its role in nutrition and metabolism ( Kan et al., 2015 ).…”

Chemical Composition, Antioxidant and Antimicrobial Activities of Essential Oils Extracted from the Fresh and Dried Seeds of Lanxangia tsao-ko grown in Nghe An, Vietnam

“…As presented in Table 1, thirty-six components were identified in HC-01 oil and thirty-three components in HC-02 oil, representing 99.32 % and 98.13 % of the related essential oils, respectively, most of which were found to be oxygenated monoterpenoids (74.57% in HC-01 oil, 68.31% in HC-02 oil), followed by monoterpene hydrocarbons (12.42% in HC-01 oil, 21.10% in HC-02 oil), aldehyde compounds (8.31% in HC-01 oil, 6.66% in HC-02 oil), and phenolics compounds (4.02% in HC-01 oil, 2.06% in HC-02 oil). Specifically, the major constituents of the fresh seed essential oils were 1,8-cineole (40.75%), α-citral (13.67%), tetracyclo[3.3.1.0.1 (3,9)]decan-10-one (10.31%), α-phellandrene (7.88%), and β-citral (6.07%), while the dried seed essential oils were dominated by 1,8-cineole (41.08%), α-phellandrene (12.84%), α-citral (12.01%), and tetracyclo[3.3.1.0.1 (3,9)]decan-10-one (8.04%). It is remarkable that the composition of the seed EOs collected in Vietnam is partly consistent with the previous report.…”

“…6 Research has revealed that L. tsao-ko possesses multiple bioactivities important to human health, such as antioxidant, anti-inflammatory, anticancer, antidiabetic, antimicrobial, and neuroprotective effects. [7][8][9][10][11][12][13]…”

Recent Updates on Phytoconstituent Alpha-Glucosidase Inhibitors: An Approach towards the Treatment of Type Two Diabetes

“…For one of the most famous and commercial green teas in China (Lu’an guapian green tea (LGGT)), its methanol extract shows α-glucosidase inhibition activity, and when supplemented with the diet, it improves insulin sensitivity and glucose tolerance in mice [ 61 ]. For another edible spice/medicinal herb from China, Amomum tsao-ko , its methanol extract shows hypoglycemic activity in a dose-dependent manner while treating STZ-induced diabetic mice as well as in vitro [ 62 ]. After six weeks of treatment, the extract significantly decreases the fasting blood glucose in diabetic mice.…”