Extraction, Physicochemical Properties, Functional Activities and Applications of Inulin Polysaccharide: a Review

Viability and stability evaluation of microencapsulated Lactobacillus reuteri in polysaccharide-based bionanocomposite

Microencapsulation is one of the most important methods to enhance the survival of bacteria when exposed to various harsh conditions. The present study evaluated the viability of L. reuteri ATCC 23272 microencapsulated in polysaccharide-based bionanocomposite. Inulin, polydextrose, and pectin were utilized as prebiotics, and magnesium oxide nanoparticles (MgO NPs) as reinforcing agent in the microgel structure. The composition of bionanocomposite was optimized using the simplex-lattice mixture method. Bionanocomposite optimal formulation was achieved by combining 91.6 % inulin and 8.4 % pectin in the presence of MgO NPs. L. reuteri prebiotic score (1.33) and E. coli (1.08), extrusion efficiency (97.57 %), viability after drying (99.37 %), and viability in simulated gastrointestinal conditions (SGI) (91.74 %) were obtained. Not using MgO NPs in the optimal composite structure caused a decrease of 2.14 log CFU/g in SGI. During 28 days of storage of bacteria at 4 and 25 °C, respectively, a reduction of 2.56 and 3.04 log CFU/g was observed for free cells compared to encapsulated cells. SEM, FTIR, and XRD analyses were performed on ingredients and microcapsules with and without bacteria. The results exhibited that the optimal bionanocomposite could be used as a beneficial encapsulation system to improve the performance of probiotics in harsh conditions.

Gel properties of sheep's hoof gelatin-dietary polysaccharide interpenetrating polymer network complex gels with application in low fat lamb patties

In order to explore new fat substitutes, we compared three dietary polysaccharides Pectin(PEC), Inulin (INU), and Konjac glucomannan (KGM) compounded with sheep hoof gelatin using different cross-linking methods [transglutaminase (Tg) enzyme; Tg enzyme & Ca2+] for the preparation of Semi-interpenetrating polymer network (Semi-IPN) and fully interpenetrating polymer network (IPN) gels. The optimal ratio was determined by comprehensively evaluating the addition of hydrogel to the lamb patties at different ratios. The results showed that PEC-IPN exhibited superior stability and textural properties compared to the Semi-IPN gels and control gels in each group. In addition, replacing 80 % of the fat in the lamb patties with PEC-IPN significantly improved the quality stability during storage, without affecting the sensory quality. Therefore, PEC-IPN instead of lamb patty fat offers a new approach for consumers.

Inulin may prevent the high-fat diet induced-obesity via suppressing endocannabinoid system in the prefrontal cortex in Wistar rats

High-fat diets contribute to various metabolic disorders. Inulin supplementation has been shown to reduce appetite, lower food intake, and promote weight loss. Although there is evidence that the endocannabinoid system has metabolic effects in the prefrontal cortex, studies investigating the effects of inulin on the endocannabinoid system are limited. This study investigated the impact of inulin on obesity through the endocannabinoid system in the prefrontal cortex. Twenty-four male Wistar rats were fed one of four diets over 12 weeks. Findings indicated that a high-fat diet led to obesity, whereas inulin reduced food intake and supported weight loss. Consequently, inulin supplementation both prevented obesity and significantly decreased the expressions of Adrb3 and Adcy1, and anandamide and 2-arachidonylglycerol levels in the prefrontal cortex. Additionally, inulin lowered leptin in circulation and stimulated Trpv1. Thus, inulin may mitigate obesity development, possibly by modulating gene expressions linked to obesity in the prefrontal cortex via endocannabinoids.

Isolation, structures, bioactivities, and applications of the polysaccharides from Boletus spp.: A review

Boletus spp., the edible mushrooms distributed in Europe, Asia, and North America, have been widely used as food and medicinal ingredients worldwide. Bioactive polysaccharides are highly abundant in Boletus spp., as demonstrated by modern phytochemical studies. The isolation, chemical properties, and bioactivities of polysaccharides from Boletus spp. have long been attracted by academics worldwide. However, there is still a lack of systematic tracking of research progress on Boletus polysaccharides (BPs), which is essential for researchers to understand their potential and gain a deeper insight into their functional mechanisms. In this review, we summarized the recent development of BPs, including the extraction and purification methods, physiochemical and structural features, bioactivities and functional mechanisms, the structure-activity relationship, and the potential applications. This review aims to provide researchers with a comprehensive understanding of the current progress and potential of BPs to assist their further investigations.

Technological Properties of Inulin-Enriched Doughs and Breads, Influence on Short-Term Storage and Glycemic Response

The use of inulin in food is highly appreciated by consumers because of its prebiotic effect. In this study, the effects of increasing additions (5, 10 and 20%) of inulin as a substitute for wheat flour in bread production were investigated with regard to the physical, technological and rheological properties of the flour blends. Inulin reduced the water-binding capacity from 1.4 g/100 g with 0 flour to 0.80 g/100 g with the 20% inulin addition, while there were no statistical differences in the oil-binding capacity. The addition of inulin also influenced the yeast rates, especially in the samples with 5 and 10% addition. On the farinograph, inulin caused a reduction in water absorption (40.75 g/100 g with 20% inulin), an increase in dough development time (18.35 min with 10% inulin) and dough stability (13.10 min with 10% inulin). The mixograph showed a longer kneading time for the sample with 20% inulin (8.70 min) than for the control (4.61 min). In addition, there was an increase in dough firmness and tightness due to the addition of inulin (W: 203 × 10-4 J; P/L: 4.55 for the 20% inulin sample) compared with the control. The physical and technological properties of the loaves were evaluated at time 0 and after 4 days (T4). The addition of inulin reduced the volume of the bread while increasing the weight, albeit with a weight loss at T4 (compared to T0) of 4.8% for the 20% inulin and 14.7% for the control. The addition of inulin caused a darkening of the crust of the enriched bread, proportional to the increase in inulin content. In addition, the inulin content ranged from 0.82 g/100 g in the control to 14.42 g/100 g in the 20% inulin bread, while the predicted glycemic index ranged from 94.52 in the control to 89.39 in the 20% inulin bread. The available data suggest that the formulation with 5% inulin provides the highest performance.

Synthesis and characterization of novel carboxymethyl inulin derivatives bearing cationic Schiff bases with antioxidant potential

This study aimed to enhance the antioxidant activity of carboxymethyl inulin (CMI) by chemical modification. Therefore, a series of cationic Schiff bases bearing heteroatoms were synthesized and incorporated into CMI via ion exchange reactions, ultimately preparing 10 novel CMI derivatives (CMID). Their structures were confirmed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. The radical scavenging activities and reducing power of inulin, CMI, and CMID were studied. The results revealed a significant enhancement in antioxidant activity upon the introduction of cationic Schiff bases into CMI. Compared to commercially available antioxidant Vc, CMID demonstrated a broader range of antioxidant activities across the four antioxidant systems analyzed in this research. In particular, CMID containing quinoline (6QSCMI) exhibited the strongest hydroxyl radical scavenging activity, with a scavenging rate of 93.60 % at 1.6 mg mL-1. The CMID bearing imidazole (2MSCMI) was able to scavenge 100 % of the DPPH radical at 1.60 mg mL-1. Furthermore, cytotoxicity experiments showed that the products had good biocompatibility. These results are helpful for evaluating the feasibility of exploiting these products in the food, biomedical, and cosmetics industries.

Metabolism of Inulin via Difructose Anhydride I Pathway in Microbacterium flavum

Difructose anhydride I (DFA-I) can be produced from inulin, with DFA-I-forming inulin fructotransferase (IFTase-I). However, the metabolism of inulin through DFA-I remains unclear. To clarify this pathway, several genes of enzymes related to this pathway in the genome of Microbacterium flavum DSM 18909 were synthesized, and the corresponding enzymes were encoded, purified, and investigated in vitro. After inulin is decomposed to DFA-I by IFTase-I, DFA-I is hydrolyzed to inulobiose by DFA-I hydrolase. Inulobiose is then hydrolyzed by β-fructofuranosidase to form fructose. Finally, fructose enters glycolysis through fructokinase. A β-fructofuranosidase (MfFFase1) clears the byproducts (sucrose and fructo-oligosaccharides), which might be partially hydrolyzed by fructan β-(2,1)-fructosidase/1-exohydrolase and another fructofuranosidase (MfFFase2). Exploring the DFA-I pathway of inulin and well-studied enzymes in vitro extends our basic scientific knowledge of the energy-providing way of inulin, thereby paving the way for further investigations in vivo and offering a reference for further nutritional investigation of inulin and DFA-I in the future.

Short-chain fatty acids in nonalcoholic fatty liver disease: New prospects for short-chain fatty acids as therapeutic targets

Nonalcoholic fatty liver disease (NAFLD) is a stress-induced liver injury related to heredity, environmental exposure and the gut microbiome metabolism. Short-chain fatty acids (SCFAs), the metabolites of gut microbiota (GM), participate in the regulation of hepatic steatosis and inflammation through the gut-liver axis, which play an important role in the alleviation of NAFLD. However, little progress has been made in systematically elucidating the mechanism of how SCFAs improve NAFLD, especially the epigenetic mechanisms and the potential therapeutic application as clinical treatment for NAFLD. Herein, we adopted PubMed and Medline to search relevant keywords such as 'SCFAs', 'NAFLD', 'gut microbiota', 'Epigenetic', 'diet', and 'prebiotic effect' to review the latest research on SCFAs in NAFLD up to November 2023. In this review, firstly, we specifically discussed the production and function of SCFAs, as well as their crosstalk coordination in the gut liver axis. Secondly, we provided an updated summary and intensive discussion of how SCFAs affect hepatic steatosis to alleviate NAFLD from the perspective of genetic and epigenetic. Thirdly, we paid attention to the pharmacological and physiological characteristics of SCFAs, and proposed a promising future direction to adopt SCFAs alone or in combination with prebiotics and related clinical drugs to prevent and treat NAFLD. Together, this review aimed to elucidate the function of SCFAs and provide new insights to the prospects of SCFAs as a therapeutic target for NAFLD.

Medicinal Plant-derived Phytochemicals in Detoxification

The average worldwide human life expectancy is 70 years, with a significantly higher value in Western societies. Many modern diseases are not associated with premature mortality but with a decreased quality of life in aged patients and an excessive accumulation of various toxic compounds in the human body during life. Today, scientists are especially interested in finding compounds that can help increase a healthy lifespan by detoxifying the body. Phytotherapy with specific approaches is used in alternative medicine to remove toxins from the body. Worldwide, research is conducted to identify medicinal plant-derived molecules that, with few or no side effects, may protect the liver and other organs. This review provides updated information about the detoxification process, the traditional and modern use of the most effective medicinal plants, their active metabolites as detoxifying agents, and the mechanisms and pathways involved in the detoxification process. Among medicinal plants with substantial detoxifying properties, a major part belongs to the Asteraceae family (Silybum marianum, Cynara scolymus, Arctium lappa, Helichrysum species, Inula helenium, and Taraxacum officinale). The most widely used hepatoprotective phytocomponent is silymarin, a standardized extract from the Silybum marianum seeds containing a mixture of flavonolignans. Many polysaccharides, polyphenols, and terpenoids have a detoxifying effect. Overall, scientific data on medicinal plants used in phytotherapeutic practice worldwide provides an understanding and awareness of their efficacy in detoxification.

Associating Inulin with a Pea Protein Improves Fast-Twitch Skeletal Muscle Mass and Muscle Mitochondrial Activities in Old Rats

Aging is associated with a decline in muscle mass and function, leading to increased risk for mobility limitations and frailty. Dietary interventions incorporating specific nutrients, such as pea proteins or inulin, have shown promise in attenuating age-related muscle loss. This study aimed to investigate the effect of pea proteins given with inulin on skeletal muscle in old rats. Old male rats (20 months old) were randomly assigned to one of two diet groups for 16 weeks: a 'PEA' group receiving a pea-protein-based diet, or a 'PEA + INU' group receiving the same pea protein-based diet supplemented with inulin. Both groups showed significant postprandial stimulation of muscle p70 S6 kinase phosphorylation rate after consumption of pea proteins. However, the PEA + INU rats showed significant preservation of muscle mass with time together with decreased MuRF1 transcript levels. In addition, inulin specifically increased PGC1-α expression and key mitochondrial enzyme activities in the plantaris muscle of the old rats. These findings suggest that dietary supplementation with pea proteins in combination with inulin has the potential to attenuate age-related muscle loss. Further research is warranted to explore the underlying mechanisms and determine the optimal dosage and duration of intervention for potential translation to human studies.