Saponins are an important class of active components in Chinese herbal medicines (CHMs), which are present in large quantities in Ginseng Radix et Rhizoma, Notoginseng Radix et Rhizoma, Polygonati Rhizoma, etc., and have immune regulation, anti-tumor, anti-inflammatory, anti-cardiovascular disease, and hypoglycemic activities. Storage and processing are essential processes in the production process of CHMs which affect the stability of saponin components and then reduce the medicinal and economic value. Therefore, it is of great importance to investigate the effects of storage and processing conditions on the content of saponin components in CHMs. In this paper, the effects of various storage and processing factors, including temperature, pH, enzymes, meta lions, extraction methods, etc., on the saponin content of CHMs are investigated and the underlying mechanisms for the quantitative changes of saponin are summarized. These findings may provide technical guidance for the production and processing of saponin-rich CHMs.

Extrusion cooking is an innovative, advanced processing technology widely used in the food and feed industries. With growing concerns over the health attributes of food, the effects of extrusion cooking on the functional characteristics of natural medicinal and edible plants (NMEPs) have attracted increasing attention from researchers. This review, based on recent literature on extrusion cooking, systematically summarizes its impact on the physical properties; functional components, such as total polyphenols, total flavonoids, total polysaccharides, and total saponins; and pharmacological activities, including antioxidant, hypoglycemic, hypolipidemic, and anti-inflammatory effects, of NMEPs. The aim is to provide a scientific basis for the application of extrusion cooking technology in the advanced processing of these resources.

Poria cocos (PC) is a famous traditional Chinese medicine (TCM) and a widely used healthcare ingredient, which has antiobesity, enhancing immunity and improving sleep effects. Traditionally, only water-soluble poria polysaccharide (WSP) is extracted and applied for clinical application, while insoluble polysaccharide (alkali-soluble poria polysaccharide, ASP) is discarded as herb residue. However, the whole PC has also been historically utilized as functional herbal food. Considering the beneficial role of dietary fiber and the traditional use of PC, ASP may also contribute substantially to the therapy function of PC. Compared to WSP, little attention has been paid to ASP and ASP modified product carboxymethyl poria polysaccharide (CMP) which has been used as an antitumor adjuvant drug. In this study, the oil, cholesterol, metal ions and polyphenols adsorption ability, in vitro simulated digestive and the gut microbiota fermentation characteristics of WSP, ASP and CMP were studied to evaluate the functional values of three Poria cocos polysaccharides (PCPs). The results showed that all three PCPs had good adsorption capacity on cholesterol, polyphenols and metal ions (Cd²⁺/Zn²⁺/Mg²⁺), among which ASP showed the highest capacity than WSP and CMP. The adsorption capacity of all three PCPs on heavy metal ions (Cd²⁺/Zn²⁺) was stronger than that of non-heavy metal ions (Mg²⁺); The in vitro digestibility of all three PCPs was very low, but WSP was slightly higher than ASP and CMP; Moreover, the indigestible residue of all three PCPs could improve the richness and diversity of gut microbiota, among which ASP had the greatest influence. In general, ASP and CMP could significantly promote the proliferation of some probiotics and inhibit the growth of some harmful bacteria. The gut microbiota diversity of CMP was reduced, but the richness of probiotics, especially Parabacteroides distasonis was significantly enhanced compared with the ASP group, and the growth of harmful bacteria Klebsiella pneumoniae was inhibited after CMP treatment. The short-chain fatty acids (SCFAs) analysis results showed that all three PCPs could significantly promote the production of acetic acid, propionic acid and the total acid content compared with BC group, and SCFAs producing activity was positively correlated with the proliferative capacity of probiotics. Taken together, the good adsorption characteristics and gut microbiota regulatory activity of ASP may lay foundation for its lipid-lowering and immune-improving function. Additionally, the probiotic effect of CMP and ASP indicated that except for only use the water extract of PC in clinic, CMP and ASP also can be used in healthcare to take full advantage of this valuable medicine.

In this study, soluble dietary fibers (SDFs) were extracted from rape bee pollen using four methods including acid extraction (AC), alkali extraction (AL), cellulase extraction (CL) and complex enzyme extraction (CE). The effects of different extraction methods on the structure of SDFs and in vitro fermentation characteristics were further investigated. The results showed that the four extraction methods significantly affected the monosaccharide composition molar ratio, molecular weight, surface microstructure and phenolic compounds content, but showed little effect on the typical functional groups and crystal structure. In addition, all SDFs decreased the Firmicutes/Bacteroidota ratio, promoted the growth of beneficial bacteria such as Bacteroides, Parabacteroides and Phascolarctobacterium, inhibited the growth of pathogenic bacteria such as Escherichia-Shigella, and increased the total short-chain fatty acids (SCFAs) concentrations by 1.63–2.45 times, suggesting that the bee pollen SDFs had a positive regulation on gut microbiota. Notably, the SDF obtained by CE exhibited the largest molecular weight, a relatively loose structure, higher extraction yield and phenolic compounds content and the highest SCFA concentration. Overall, our results indicated that CE was an appropriate extraction method of high-quality bee pollen SDF.