Ultrahigh pressure extraction of polysaccharide from Morinda officinalis and effect on the polysaccharide structure

Progress in culture technology and active substance research on Nostoc sphaeroides Kützing

Nostoc sphaeroides Kützing is a freshwater edible cyanobacterium that is rich in active substances such as polysaccharides, proteins and lipids; it has a variety of pharmacological effects such as antioxidant, anti-inflammatory, antitumor and cholesterol-lowering effects; and is often used as a traditional Chinese medicine with many potential applications in food, cosmetics, medical diagnostics and disease treatment. However, to meet the needs of different fields, such as medicine, there is an urgent need for basic research and technological innovation in culture technology, extraction and preparation of active substances, and the pharmacological mechanism of N. sphaeroides. This paper reviews the pharmacological effects of N. sphaeroides active substances, discusses current culture techniques and methods for extracting active components, and outlines the challenges encountered in cultivating and industrializing N. sphaeroides while discussing future development trends. © 2024 Society of Chemical Industry.

Plant polysaccharides extracted by high pressure: A review on yields, physicochemical, structure properties, and bioactivities

Polysaccharides are biologically essential macromolecules, widely exist in plants, which are used in food, medicine, bioactives' encapsulation, targeted delivery and other fields. Suitable extraction technology can not only improve the yield, but also regulate the physicochemical, improve the functional property, and is the basis for the research and application of polysaccharide. High pressure (HP) extraction (HPE) induces the breakage of raw material cells and tissues through rapid changes in pressure, increases extraction yield, reduces extraction time, and modifies structure of polysaccharides. However, thus far, literature review on the mechanism of extraction, improved yield and modified structure of HPE polysaccharide is lacking. Therefore, the present work reviews the mechanism of HPE polysaccharide, increasing extraction yield, regulating physicochemical and functional properties, modifying structure and improving activity. This review contributes to a full understanding of the HPE or development of polysaccharide production and modification methods and promotes the application of HP technology in polysaccharide production.

The Physicochemical Properties and Antioxidant Activities of the Hawthorn Pectin Extracted Using Ultra-High Pressure Assisted Acid Extraction (UPAAE)

This study aims to investigate the positive effects of ultra-high pressure assisted acid extraction (UPAAE) on both physicochemical properties and antioxidant activities of hawthorn pectin. The basic indicators, structure characterization, and antioxidant activities were measured, which could indicate the disadvantages and advantages among traditional water extraction (WE), acid extraction (AE), and UPAAE. The results show that the hawthorn pectin of UPAAE has a decrease in esterification degree, protein content, and total polyphenols, but has an increase in total galacturonic acid aldehyde compared to the hawthorn pectin of AE. In the Fourier Transform Infrared Spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM) analyses, the hawthorn of UPAAE has typical pectin absorption peaks in the FT-IR spectrum and a distinct layered structure in the SEM surface image. The ion chromatography profiles show that the molar ratio of galacturonic acid to arabinose in the hawthorn pectin of UPAAE increases and 5.50 μg/mg ribose appears compared to the pectin of AE and WE. The high performance gel permeation chromatography (HPGPC) profile indicates that the molecular weight distribution of hawthorn pectin of UPAAE is more concentrated and has the highest molecular weight compared to the pectin of the other two extraction methods. In the vitro antioxidant activity analysis, the pectin of UPAAE exhibits the highest scavenging rate against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals (93.70%), which is close to the scavenging rate of vitamin C (96.30%). These findings demonstrated that UPAAE is a more efficient and environmentally friendly method for pectin extraction from hawthorn. It is also an effective way to enhance its antioxidant activity, which has great application prospects in the food industries.

The extraction and anti-inflammatory screening of Onosma glomeratum Y. L. Liu

"Zicao" has a long medicinal history and has a variety of pharmacological activities. As the main resource of "zicao" in Tibet, Onosma glomeratum Y. L. Liu (tuan hua dian zi cao), usually used for treating pneumonia in Tibet, has not been reported deeply. In order to determine the main anti-inflammatory active ingredients of Onosma glomeratum Y. L. Liu, in this study, the extracts enriched in naphthoquinones and polysaccharides were optimized prepared form Onosma glomeratum Y. L. Liu by ultrasonic extraction, and reflux extraction, respectively, with Box-Behnken design effect surface method. And their anti-inflammatory abilities were screened on LPS induced A549 cells model, for figuring out the anti-inflammatory active ingredients from Onosma glomeratum Y. L. Liu.The extract enriched naphthoquinone was obtained under following condition: extract with 85% ethanol in a liquid to material ratio of 1:40 g/mL at 30 °C for 30 minutes using ultrasound, leading to the extraction rate of total naphthoquinone as 0.98 ± 0.017%; the extract enriched polysaccharides was prepared as follows: extract 82 minutes at 100 °C with distilled water in a liquid to material ratio of 1:50 g/mL, with extraction rate of polysaccharide as 7.07 ± 0.02%.On the LPS-induced A549 cell model, the polysaccharide extract from Onosma glomeratum Y. L. Liu showed better anti-inflammatory effects than the naphthoquinone extract, indicating the extract enriched in polysaccharides is the anti-inflammatory extract of Onosma glomeratum Y. L. Liu, which could serve as a potential anti-inflammatory extract in medical and food industries in the future.

Effect of high hydrostatic pressure on activity, thermal stability and structure of horseradish peroxidase

The mechanism of the high hydrostatic pressure (HHP) effect on horseradish peroxidase (HRP) is still unclear. The activity, thermal stability and structural changes of HRP after HHP treatments were studied in this work. Compared with the untreated sample, the enzyme activity reduces by 36% after 800 MPa processing. The results indicated that the conformation of the enzyme active center changes under pressure. Furthermore, HHP also changes the conformation of disulfide bonds and some secondary structures in HRP. These structural and conformational changes induce decreased activity. In addition, differential thermal scanning (DSC) results showed that the thermal denaturation temperature decreased from 103.74 °C to 85.78 °C after pressure treatment, suggesting HRP molecules formed large aggregates after pressure treatment. In this study, the interaction mechanism between pressure and enzyme was studied as well, and the results can provide some guidance for the application of HHP technology in fruit and vegetable products processing.