•One new compound and nineteen known compounds were isolated and characterized.•Ten compounds and total flavonoids exhibited anti-complementary activities in vitro.•Six compounds and total flavonoids inhibited α-glucosidase activity in vitro.•Total flavonoids showed antihyperglycaemic effects on STZ-induced diabetic mice.•G. hypoleucum could be used as functional food applications for diabetics.Gnaphalium hypoleucum DC is used as a wild vegetable, named “Qing Ming Cai”, as well as a folk medicine in China. One new compound, Gnaphaliin C, and nineteen known compounds were isolated and indentified from G. hypoleucum, total flavonoids were analyzed by UHPLC-Q-TOF/MS. The α-glucosidase inhibitory and anti-complementary activities of all compounds and total flavonoids were evaluated. Total flavonoids and ten compounds exhibited anti-complementary activities. Total flavonoids and six compounds inhibited α-glucosidase. The antihyperglycaemic effects of total flavonoids were investigated by streptozotocin (STZ)-induced diabetic mice. Total flavonoids improved the glucose tolerance and decreased blood sugar, increased muscle glycogen content, decreased the levels of triacylglycerol (TG) and total cholesterol (TC), enhanced superoxide dismutase (SOD) activity and decreased malondialdehyde (MDA) level in diabetic mice. G. hypoleucum and its total flavonoids could be used as functional food for diabetics.

•Five caffeoyl compounds were identified from purple sweet potato Ipomoea batatas.•Two caffeoyl compounds were found for the first time.•These antioxidation activities were related to the number of caffeoyl group.More than 10 red anthocyanins and related glucosides have been isolated and identified from purple sweet potato (Ipomoea batatas, Ayamurasaki) in the recent decades. This paper reports the isolation of colourless caffeoyl compounds from purple sweet potato using AB-8 macroresin absorption and semi-preparative HPLC-DAD. The structures of the five isolated monomers were identified as: 5-caffeoylquinic acid (1), 6-O-caffeoyl-β-d-fructofuranosyl-(2-1)-α-d-glucopyranoside (2) and trans-4,5-dicaffeoylquinic acid (3), 3,5-dicaffeoylquinic acid (4), 4,5-dicaffeoylquinic acid (5), and by ESI/MS and NMR. Compounds 1, 4 and 5 were reported previously in combination with anthocyanins in purple sweet potato, whereas 2 and 3 were found for the first time. In vitro antioxidant assay showed trans-4,5-dicaffeoylquinic acid has significant antioxidant activities. These results should lay the groundwork for further work identifying purple sweet potato as a healthy food.

•V. bracteatum had strong antioxidant effects assessed by DPPH and ORAC in vitro.•V. bracteatum exhibited a protective effect on KBrO3-induced kidney damage.•The antioxidant compounds were isolated, qualitatively and quantitatively analyzed.•Flavonoids were responsible for the antioxidant effect.Vaccinium bracteatum Thunb. is commonly used to stain and cook the rice, which then becomes black, named Wu Fan in Chinese. However, there are limited modern data on its pharmacological effects and active components relating to its traditional use. In the present study, the 50% EtOH eluates (C-b) of V. bracteatum exhibited a strong antioxidant effect assessed by two antioxidant assays (DPPH, ORAC) in vitro and a protective effect on KBrO3-induced kidney damage. Seven compounds in the C-b were identified as isoorientin (1), orientin (2), vitexin (3), isovitexin (4), isoquercitrin (5), quercetin-3-O-α-L-rhamnoside (6), and chrysoeriol-7-O-β-D-glucopyranoside (7). These seven compounds accounted for 0.31 mg/mg of C-b by HPLC analysis, and C-b mainly contained flavonoid compounds by UHPLC-Q-TOF-MS analysis. Flavonoids, especially isoorientin and orientin, were found to be responsible for the antioxidant effect. The results demonstrate that flavonoids may contribute to the health benefits of V. bracteatum in Chinese traditional food.

Ethnopharmacological relevanceEupatorium lindleyanum DC. is widely used for its efficiency in treating cough, tracheitis and tonsillitis. Acute lung injury (ALI) induced by lipopolysaccharide (LPS) in mice was used to investigate therapeutic effects and possible mechanism of the sesquiterpenes fraction of E. lindleyanum DC. (EUP-SQT).Materials and methodsMice were orally administrated with EUP-SQT (15, 30 and 60 mg/kg) per day for 7 days consecutively before LPS challenge. The lung specimens and bronchoalveolar lavage fluid (BALF) were harvested for histopathological examinations and biochemical analysis at 6 h and 24 h after LPS challenge. The level of complement 3 (C3) and complement 3c (C3c) in serum was quantified by a sandwich ELISA kit.ResultsPretreatment with EUP-SQT could significantly decrease lung wet-to-dry weight (W/D) ratio, nitric oxide (NO) and protein concentration in BALF, which was exhibited together with the lowered myeloperoxidase (MPO) activity, the increased superoxide dismutase (SOD) activity and down-regulation the level of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) in ALI model. Additionally, EUP-SQT attenuated lung histopathological changes and significantly reduced complement deposition with decreasing the level of C3 and C3c in serum.ConclusionsThese results showed that EUP-SQT significantly attenuated LPS-induced ALI via reducing productions of pro-inflammatory mediators and decreasing the level of complement, indicating it as a potential therapeutic agent for ALI.Download high-res image (244KB)Download full-size image