Mechanochemical-Assisted Extraction and Antioxidant Activities of Kaempferol Glycosides from Camellia oleifera Abel. Meal

Abstract

A mechanochemical-assisted extraction (MCAE) method was proposed and investigated for the fast extraction of two kaempferol glycosides (kaempferol-3-O-[2-O-β-D-galactopyranosyl-6-O-α-L-rhamnopyranosyl]-β-D-glucopyranoside and kaempferol-3-O-[2-O-β-D-xylopyranosyl-6-O-α-L-rhamnopyranosyl]-β-D-glucopyranoside) from Camellia oleifera Abel. meal. The effects of operating parameters in terms of NaOH content, grinding time, extraction time, and ratio of solution to solid were evaluated by means of response surface methodology (RSM). Under the optimal conditions with a ratio of material to NaOH of 20:1 (g/g), a milling time of 15 min, and a ratio of solution to solid of 20:1 (mL/g) for 60 min, the maximum extraction yields of the two kaempferol glycosides reached 13.34 and 13.83%, respectively. The antioxidant activity of kaempferol glycosides extract was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay and ferric thiocyanate (FTC) assay. Compared with the heat reflux extraction (HRE) method, the yield and the antioxidant activities of the extracts from MCAE with water as solvent were higher and stronger.

Two Kaempferol Glycosides Separated from Camellia Oleifera Meal by High‐Speed Countercurrent Chromatography and Their Possible Application for Antioxidation

“…DEPT-135 spectrum showed the presence of two methyls, one methylene, 21 methines, and nine nonprotonated carbons. By comparing the above data with the reported data (Fang, Rao, & Tzeng, 2005), compound 2 was determined to be kaempferol-3 (Chen, Wu et al, 2010;Liau et al, 2017;Zhu et al, 2011), the present study reported another two kaempferol glycosides isolated and purified by HSCCC from C. oleifera meal. It should be noted that O-glycosylation of these two compounds occurs at both C-3 and C-7 positions, which was seldom found in C. oleifera and other natural plants.…”

“…Although several kaempferol glycosides have been previously identified from C . oleifera meal, such as kaempferol 3‐ O ‐[2‐ O ‐ β ‐D‐xylopyranosyl‐6‐ O ‐ α ‐L‐ rhamnopyranosyl]‐ β ‐D‐glucopyranoside and kaempferol 3‐ O ‐[2‐ O ‐ β ‐D‐ galactopyranosyl‐6‐ O ‐ α ‐L‐rhamnopyranosyl]‐ β ‐D‐glucopyrnoside (Chen, Wu et al., ; Liau et al., ; Zhu et al., ), the present study reported another two kaempferol glycosides isolated and purified by HSCCC from C. oleifera meal. It should be noted that O ‐glycosylation of these two compounds occurs at both C‐3 and C‐7 positions, which was seldom found in C. oleifera and other natural plants.…”

“…Interestingly, most flavonoids in plants appear as glycosides, and exhibit better biological activities compared with the corresponding aglycones (Chen, Teng et al., ). Various methods for extracting phytochemicals from agrifood waste have been developed in the recent years, and many kaempferol glycosides have been identified and purified from C. oleifera meal (Zhu, Lin, Chen, Xie, & Wang, ). However, the efficiency of extraction and purification of kaempferol glycosides is still rather low, and there are new kaempferol glycosides remaining to be explored from C. oleifera meal.…”

A review of the dietary flavonoid, kaempferol on human health and cancer chemoprevention

“…Response surface methodology (RSM) was used to build a model from four independent factors including extraction time, pressure, temperature and ethanol content of modifier. Zhu, Lin, Chen, Xie, and Wang (2011) used a mechanochemical-assisted extraction (MCAE) method in extracting kaempferol from Camellia oleifera Abel. meal.…”

Production of yellow wine from Camellia Oleifera meal pretreated by mixed cultured solid‐state fermentation

“…Meanwhile, there are also various biological activities and active constituents in C. oleifera meal, which has drawn increasing attention and considerable interest during the past decades (Bin et al, 2010). Two kaempferol glycosides had been found in C. oleifera meal and showed an inhibitory effect on the arachidonate 5-lipoxygenase of RBL-1 cells (Sekine et al, 1991(Sekine et al, , 1993Li et al, 2010;Zhu et al, 2011). Furthermore, tea saponin (TS) is a polysaccharide terpenoid in the meal and confers it many pharmacological activities, such as anti-inflammatory (Chattopadhyay et al, 2004;Yuan et al, 2006), antiallergic (Akagi et al, 1997), anticholesterol (Feng et al, 1998) and hepatoprotective effect (Lai et al, 2004).…”