Purification and Characterization of Resistant Dextrin

Digestive characteristics of Gastrodia elata Blume polysaccharide and related impacts on human gut microbiota in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Gastrodia elata Blume is a traditional Chinese medicine with the effects of improving the deficiency of the body and maintaining health, and polysaccharide (GEP) is one of the effective ingredients to play these activities of G. elata. Traditionally, G. elata is orally administered, so the activities of GEP are associated with digestive and intestinal metabolism. However, the digestive behavior of GEP and its effects on the human gut microbiota are unclear and need to be fully studied.

AIM OF THE STUDY

This study aimed to investigate the changes in structural characteristics of GEP during digestion and the related impacts of its digestive product on gut microbiota in human fecal fermentation, and to explain the beneficial mechanism of GEP on human health from the perspective of digestive characteristics and "gut" axis.

MATERIALS AND METHODS

The changes of reducing sugars, free monosaccharides and physicochemical properties of GEP during digestion were investigated by GPC, HPLC, FT-IR, CD, NMR, SEM, and TGA. Moreover, polysaccharide consumption, pH value changes, SCFAs production, and changes in gut microbiota during fermentation were also discussed.

RESULTS

During digestion of GEP, glucose was partially released causing a decrease in molecular weight, and a change in monosaccharide composition. In addition, the characteristics of GEP before and after digestion, including configuration, morphology, and stability, were different. The digestive product of GEP was polysaccharide (GEP-I), which actively participated in the fecal fermentation process. As the fermentation time increased, the utilization of GEP-I by the microbiota gradually increased. The abundance of probiotics such as Bifidobacterium, Collinsella, Prevotella, and Faecalibacterium was significantly increased, and the abundance of pathogenic Shigella, Dorea, Desulfovibrio, and Blautia was significantly inhibited, thereby suggesting that GEP has the potential to maintain human health through the "gut" axis. In addition, the beneficial health effects of GEP-I have also been observed in the influence of microbial metabolites. During the fermentation of GEP-I, the pH value gradually decreased, and the contents of beneficial metabolites such as acetic acid, propionic acid, and caproic acid significantly increased.

CONCLUSION

The structure of GEP changed significantly during digestion, and its digestive product had the potential to maintain human health by regulating gut microbiota, which may be one of the active mechanisms of GEP.

G. R, Sudhakaran. V. A, Warrier AS, Singh NK. Unveiling the Health Benefits of Prebiotics: A Comprehensive Review

Prebiotics play a pivotal role in fostering probiotics, essential contributors to the creation and maintenance of a conducive environment for beneficial microbiota within the human gut. To qualify as a prebiotic, a substance must demonstrate resilience to stomach enzymes, acidic pH levels, and intestinal bacteria, remaining unabsorbed in the digestive system while remaining accessible to gut microflora. The integration of prebiotics and probiotics into our daily diet establishes a cornerstone for optimal health, a priority for health-conscious consumers emphasizing nutrition that supports a balanced gut flora. Prebiotics offer diverse biological functions in humans, exhibiting antiobesity, antimicrobial, anticancer, anti-inflammatory, antidiabetic, and cholesterol-lowering properties, along with preventing digestive disorders. Numerous dietary fibers possessing prebiotic attributes are inadvertently present in our diets, emphasizing the broader significance of prebiotics. It is crucial to recognize that, while all dietary fibers are prebiotics, not all prebiotics fall under the category of dietary fibers. The versatile applications of prebiotics extend across various industries, such as dairy, bakery, beverages, cosmetics, pharmaceuticals, and other food products. This comprehensive review provides insights into different prebiotics, encompassing their sources, chemical compositions, and applications within the food industry.

Characterization, health benefits, and food applications of enzymatic digestion- resistant dextrin: A review

Resistant dextrin or resistant maltodextrin (RD), a short-chain glucose polymer that is highly resistant to hydrolysis by human digestive enzymes, has shown broad developmental prospects in the food industry and has gained substantial attention owing to its lack of undesirable effects on the sensory features of food or the digestive system. However, comprehensive fundamental and application information on RD and how RD improves anti-diabetes and obesity have not yet been received. Therefore, the characterization, health benefits and application of RD in various fields are summarized and discussed in the current study. Typically, RD is prepared by the acid thermal method and possesses excellent physicochemical properties, including low viscosity, high solubility, storage stability, and low retro-gradation, which are correlated with its low molecular weight (Mw) and non-digestible glycosidic linkages. In contrast, RD prepared by the simultaneous debranching and crystallization method has low solubility and high crystallinity. The ingestion of RD can positively affect metabolic diseases (diabetes and obesity) in animals and humans by producing short-chain fatty acids (SCFAs), and facilitating the inflammatory response. Moreover, RD has been widely used in the beverage, dairy products, and dessert industries due to its nutritional value and textural properties without unacceptable quality loss. More studies are required to further explore RD application potential in the food industry and its role in the management of different chronic metabolic disorders.

A Comparative Study of Resistant Dextrins and Resistant Maltodextrins from Different Tuber Crop Starches

The anti-digestibility of resistant dextrin (RD) and resistant maltodextrin (RMD) is usually significantly affected by processing techniques, reaction conditions, and starch sources. The objective of this investigation is to elucidate the similarities and differences in the anti-digestive properties of RD and RMD prepared from three different tuber crop starches, namely, potato, cassava, and sweet potato, and to reveal the associated mechanisms. The results show that all RMDs have a microstructure characterized by irregular fragmentation and porous surfaces, no longer maintaining the original crystalline structure of starches. Conversely, RDs preserve the structural morphology of starches, featuring rough surfaces and similar crystalline structures. RDs exhibite hydrolysis rates of approximately 40%, whereas RMDs displaye rates lower than 8%. This disparity can be attributed to the reduction of α-1,4 and α-1,6 bonds and the development of a highly branched spatial structure in RMDs. The indigestible components of the three types of RDs range from 34% to 37%, whereas RMDs vary from 80% to 85%, with potato resistant maltodextrin displaying the highest content (84.96%, p < 0.05). In conclusion, there are significant differences in the processing performances between different tuber crop starches. For the preparation of RMDs, potato starch seems to be superior to sweet potato and cassava starches. These attributes lay the foundation for considering RDs and RMDs as suitable components for liquid beverages, solid dietary fiber supplements, and low glycemic index (low-GI) products.

Effects of Steaming on Sweet Potato Soluble Dietary Fiber: Content, Structure, and Lactobacillus Proliferation In Vitro

The influence of steaming treatment on the soluble dietary fiber (SDF) of sweet potato was investigated. The SDF content increased from 2.21 to 4.04 g/100 g (in dry basis) during 20 min of steaming. The microcosmic morphology of the fractured cell wall indicated the release of SDF components during steaming. The SDF from fresh (SDF-F) and 20 min steamed (SDF-S) sweet potato was characterized. The neutral carbohydrates and uronic acid levels in SDF-S were significantly higher than SDF-F (59.31% versus 46.83%, and 25.36% versus 9.60%, respectively) (p < 0.05). The molecular weight of SDF-S was smaller than SDF-F (5.32 kDa versus 28.79 kDa). The probiotic property was evaluated by four Lactobacillus spp. fermentation in vitro with these SDF as carbon source, using inulin as the references. SDF-F showed the best proliferation effects on the four Lactobacillus spp. in terms of the OD₆₀₀ and pH in cultures, and the highest production of propanoic acid and butyric acid after 24 h fermentation. SDF-S presented higher Lactobacillus proliferation effects, but slight lower propanoic acid and butyric acid production than inulin. It was concluded that 20 min of steaming released SDF with inferior probiotic properties, which might derive from the degraded pectin, cell wall components, and resistant dextrin.