⿢An active polysaccharide (DHPD1) was isolated from Dendrobium huoshanense.⿢DHPD1 was shown to inhibit the apoptosis of human lens epithelial cells.⿢The active core domain of DHPD1 was prepared using pectinase hydrolyzation.⿢The basic structure features of the core domain of DHPD1 were characterized.⿢DHPD1 and its core domain prevent cell apoptosis via alleviating cell inflammation.The aim of this work was to investigate the core structure of a Dendrobium huoshanense polysaccharide DHPD1 required for the inhibition of lens epithelial cell apoptosis. In order to obtain the fragments containing the core domain, pectinase was employed to hydrolyze DHPD1. After 24 h reaction, it is interesting that the hydrolyzation seemed to be stopped, leading to a final enzymatic fragment DHPD1-24 with molecular weight about 1552 Da. Compared to DHPD1, although the bioactivity is decreased, DHPD1-24 remained the ability to inhibit the H2O2-induced apoptosis of human lens epithelial (HLE) cells via suppressing the MAPK signaling pathways. These results suggested that DHPD1-24 might be the core domain required for DHPD1 to inhibit HLE cell apoptosis. Methylation analysis showed DHPD1-24 was composed of (1 ⿿ 5)-linked-Araf, (1 ⿿ 3,6)-linked-Manp, 1-linked-Glcp, (1 ⿿ 4)-linked-Glcp, (1 ⿿ 6)-linked-Glcp, (1 ⿿ 4,6)-linked-Glcp, (1 ⿿ 6)-linked-Galp and 1-linked-Xylp in a molar ratio of 1.06:1.53:2.11:2.04:0.93:0.91:0.36:1.01. Moreover, the primary structural features of DHPD1-24 were characterized by NMR spectrum.

•The amylopectin was extracted from lotus root (LRA).•The addition of LRA enhanced the texteral and thermal properties of WPI gels.•The addition of LRA resulted in a stable three-dimensional gel network of WPI.•LRA might be a good candidate for the gel production in food industry.The effects of lotus root amylopectin (LRA) on the formation of whey protein isolate (WPI) gels were investigated at the concentration range from 0 to 1.0% (w/v) by determining the texteral, thermal and rheological properties. Results exhibited these properties of WPI gels could be significantly enhanced by the addition of LRA in a concentration-dependent manner. Compared the gel with free of starch, the gel strength, water holding capacity and thermal transition temperature of WPI gel containing 1% (w/v) amylopectin were enhanced by 12.7-fold, 24.9% and 3.6 °C, respectively. According to the analysis of scanning electron microscopy, colorimetric reaction and Fourier transform infrared spectroscopy measurements, it was concluded that the LRA-induced enhancement of WPI gel properties was possibly attributed to the formation of stable three-dimensional gel network, increased contents of reactive sulfhydryl group, CN bond and/or NH bond. Results suggested that LRA might be a good gel modifier.

•Polysaccharide (CCP) is one of the main active compounds in Chinese chive.•Ultrasound-assisted extraction method was employed to extract CCP in this work.•A kinetic model was established to describe the extraction process of CCP.•Based on the model, the extraction condition was optimized for CCP extraction.•The ultrasound-acted target of CCP was determined in the process of extraction.Chinese chive, a famous green vegetable, is widely cultivated in the Asia. In the present study, we found that ultrasound caused the degradation of Chinese chive polysaccharides (CCP) in the process of extraction. Since lacking the consideration of polysaccharide degradation, the traditional kinetic models can not reflect the real extraction process of CCP. Therefore, a modified kinetic model was thus established by introducing a parameter of degradation coefficient based on the Fick’s second law, suggesting the diffusion and degradation of CCP is highly dependent on the ultrasonic power, extraction temperature and solid-liquid ratio. According to this modified model, the maximum CCP yield was obtained under an optimal extraction condition including extraction temperature 37 °C, ultrasonic power 458 w, extraction time 30 min and solid-liquid ratio 1:32. The objective polysaccharides responding to ultrasound were shown to be four different fractions, contributing to the increased diffusion and degradation of CCP by ultrasound treatment.

•Extraction conditions of polysaccharide from jellyfish (JSP) were optimized.•The methods to remove proteins from crude JSP were studied.•The ethanol precipitation conditions for JSP purification were investigated.•The physicochemical properties of different JSP fractions were compared.•JSP showed strong inhibitory effects on macrophage-derived foam cell formation.In this work, response surface methodology was used to determine optimum conditions for extraction of polysaccharides from jellyfish skin (JSP). The optimum parameters were found to be raw material to water ratio 1:7.5 (w/v), extraction temperature 100 °C and extraction time 4 h. Under these conditions, the JSP yield reached 1.007 mg/g. Papain (15 U/mL) in combination with Sevag reagent was beneficial in removing proteins from JSP. After precipitation with ethanol at final concentration of 40%, 60% and 80% in turn, three polysaccharide fractions of JSP1, JSP2 and JSP3 were obtained from JSP, respectively. The three fractions exhibited different physicochemical properties with respect to molecular weight distribution, monosaccharide composition, infrared absorption spectra, and glycosyl bond composition. In addition, JSP3 showed strong inhibitory effects on oxidized low-density lipoprotein (oxLDL) induced conversion of macrophages into foam cells, which possibly attributed to the down-regulation of some atherogenesis-related gene expressions.