Antioxidant activity, α-glucosidase inhibition, and phytochemical fingerprints ofAnoectochilus roxburghiiformula tea residues with HPLC-QTOF-MS/MS

Abstract

This study assessed the phytochemical composition, antioxidant activities, and α‐glucosidase inhibition of Anoectochilus roxburghii formula tea (ARFT) residue by comparing with that of ARFT infusion and ARFT extract. ARFT residue extract showed the maximum total phenolics, total flavonoids, and total condensed tannins content, with the values of 146.70 GAE mg/g E, 58.50 QE mg/g E, and 312.08 mg CE/g E, respectively, while ARFT infusion exhibited the lowest values. The strongest ABTS+· scavenging ability and α‐glucosidase inhibition were also found in ARFT residue extract, but the best DPPH· scavenging ability was observed on the 95% ethanol extract of ARFT. Totally, 29 compounds were tentatively identified from the ARFT residue extract by using HPLC‐QTOF‐MS/MS, including 2 organic acids, 17 flavonoids, 4 fatty acids, 5 saponins, and 1 sugar. The results indicated that ARFT residue can be a promising source of natural antioxidants and α‐glucosidase inhibitors. Practical applications Anoectochilus roxburghii formula tea (ARFT) is a popular health‐promoting tea in China, but research on the bio‐activities and functional constitution of ARFT and its residues is not available. This study suggested promising antioxidant and α‐glucosidase inhibition of ARFT residue and revealed the presence of 29 major phytochemical compounds, which indicated that ARFT residue can be a potential resource of natural antioxidants and α‐glucosidase inhibitors in food, cosmetic, and pharmaceutical industry.

Ultrasound-Assisted Extraction Optimization of α-Glucosidase Inhibitors from Ceratophyllum demersum L. and Identification of Phytochemical Profiling by HPLC-QTOF-MS/MS

“…Consequently, their derivatives will exhibit corresponding characteristic aglycone ions by losing glycoside moiety, e.g., pentosyl (132 Da), glucosyl (162 Da), hexosyl (162 Da), rhamnosyl (146 Da) or rutinosyl (308 Da). Under negative ion mode, flavonoids will exhibit typical losses of CO, CO 2 , C 3 O 2 , and C 2 H 2 O. Flavones are more likely to produce ions at 1,3 A − and 1,3 B − , and flavonols are easier to get fragment ions at 1,2 A − and 1,2 B − [ 36 , 37 ]. In addition, when the glycosidic bond is bonded to the 3-OH position of aglycone, Y 0 − and [Y 0 − H] − fragments will occur, but the intensity of [Y 0 − H] − is customarily higher than that of Y 0 − [ 38 ].…”

“…Peak 72 with molecular ion at m/z 291.1980 was identified as 12-oxo-phytodienoic acid, and the fragmentation pattern is shown in Figure 5 g. Its MS/MS ions at 273.1857 and 247.2078 result from the loss of a water molecule and a carboxylic residue, respectively [ 43 ]. Peak 73 (559.3142, C 28 H 48 O 11 ) was tentatively assigned as dirhamnosyl linolenic acid, fragment ion at 277.2186 resulted from the loss of a dirhamnosyl (C 10 H 18 O 9 , 282 Da) [ 36 ].…”

Neuroprotective effects of Camellia nitidissima Chi leaf extract in hydrogen peroxide‐treated human neuroblastoma cells and its molecule mechanisms

“…Peak 5 (Rt 11.513 min) with the extract ion chromatogram at m/z 337.0962 demonstrated the fragments at m/z 119 and 163, which was corresponding to the loss of C 8 H 11 O 7 and C 7 H 11 O 5 , respectively. The peak was considered as p‐Coumaroyl‐quinic acid (Baskaran et al., 2016; Xie et al., 2017; Yang, Guan, et al, 2018).…”

“…Peak 27, 24, and 35 (Rt 20.149, 19.679 and 23.764 min) with the extract ion chromatogram at m/z 433.0776, 609.1462, and 755.1826, all demonstrated the fragment at m/z 285 which was considered to be [M‐H‐132] − , [M‐H‐162‐146] − and [M‐H‐146‐162‐146] − , respectively. They were identified asquercetin pentoside, quercetin‐glucoside‐rhamnoside (Xie et al., 2017), and quercetin‐3‐O‐[2‐O‐(6‐O‐p‐hydroxyl‐E‐coumaroyl)‐D‐glucosyl]‐(1‐2)‐L‐rhamnoside, respectively.…”

Antioxidant, antihypertensive, and anticancer activities of the flavonoid fractions from green, oolong, and black tea infusion waste

“…Regular consumption of tea is of great benefit to human health, such as preventing chronic diseases, reducing inflammation, preventing cancer and delaying aging (Xie et al, ). Tea is generally consumed in three forms including green tea (unfermented), oolong tea (semifermented) and black tea (fermented) (Chen, Qu, Fu, Dong, & Zhang, ).…”