Optimization of enzymatic production of prebiotic galacto/galacto(arabino)-oligosaccharides and oligomers from potato rhamnogalacturonan I

Nanostructured supports for multienzyme co-immobilization for biotechnological applications: Achievements, challenges and prospects

The synergistic combination of current biotechnological and nanotechnological research has turned to multienzyme co-immobilization as a promising concept to design biocatalysis engineering. It has also intensified the development and deployment of multipurpose biocatalysts, for instance, multienzyme co-immobilized constructs, via biocatalysis/protein engineering to scale-up and fulfil the ever-increasing industrial demands. Considering the characteristic features of both the loaded multienzymes and nanostructure carriers, i.e., selectivity, specificity, stability, resistivity, induce activity, reaction efficacy, multi-usability, high catalytic turnover, optimal yield, ease in recovery, and cost-effectiveness, multienzyme-based green biocatalysts have become a powerful norm in biocatalysis/protein engineering sectors. In this context, the current state-of-the-art in enzyme engineering with a synergistic combination of nanotechnology, at large, and nanomaterials, in particular, are significantly contributing and providing robust tools to engineer and/or tailor enzymes to fulfil the growing catalytic and contemporary industrial needs. Considering the above critics and unique structural, physicochemical, and functional attributes, herein, we spotlight important aspects spanning across prospective nano-carriers for multienzyme co-immobilization. Further, this work comprehensively discuss the current advances in deploying multienzyme-based cascade reactions in numerous sectors, including environmental remediation and protection, drug delivery systems (DDS), biofuel cells development and energy production, bio-electroanalytical devices (biosensors), therapeutical, nutraceutical, cosmeceutical, and pharmaceutical oriented applications. In conclusion, the continuous developments in nano-assembling the multienzyme loaded co-immobilized nanostructure carriers would be a unique way that could act as a core of modern biotechnological research.

Cocoa bean shells: a review into the chemical profile, the bioactivity and the biotransformation to enhance their potential applications in foods

During processing, cocoa bean shells (CBS) are de-hulled from the bean and discarded as waste. Undermined by its chemical and bioactive composition, CBS is abundant in dietary fiber and phenolic compounds that may serve the valorization purpose of this by-product material into prebiotic and functional ingredients. In addition, the cell-wall components of CBS can be combined through enzymatic feruloylation to obtain feruloylated oligo- and polysaccharides (FOs), further enhancing the techno-functional properties. FOs have attracted scientific attention due to their prebiotic, antimicrobial, anti-inflammatory and antioxidant functions inherent to their structural features. This review covers the chemical and bioactive compositions of CBS as well as their modifications upon cocoa processing. Physical, chemical, and enzymatic approaches to extract and bio-transform bioactive components from the cell wall matrix of CBS were also discussed. Although nonspecific to CBS, studies were compiled to investigate efforts done to extract and produce feruloylated oligo- and polysaccharides from the cell wall materials.

Sources, Processing-Related Transformation, and Gut Axis Regulation of Conventional and Potential Prebiotics

One strategy to achieve a balanced intestinal microbiota is to introduce prebiotics. Some substances present in the diet, such as soybean extracts, koji glycosylceramides, grape extracts, tea polyphenols, and seaweed extracts, can be considered as potential prebiotics, because they can selectively stimulate the proliferation of beneficial bacteria in the intestine. However, the discovery of novel prebiotics also involves advances in screening methods and the use of thermal and non-thermal processing techniques to modify and enhance the properties of beneficial organisms. The health benefits of prebiotics are also reflected by their participation in regulating the microbiota in different gut axes. In the present review, we introduced the field of prebiotics, focusing on potential prebiotic substances, the process of screening potential prebiotics, the transformation of prebiotics by food-processing technologies, and the roles of prebiotics on gut axis regulation, which, it is hoped, will promote the discovery and utilization of novel prebiotics.

Potential Impacts of Prebiotics and Probiotics in Cancer Prevention

BACKGROUND

Cancer is a serious problem throughout the world. The pathophysiology of cancer is multifactorial and is also related to gut microbiota. Intestinal microbes are the useful resident of the healthy human. They play various aspects of human health including nutritional biotransformation, flushing of the pathogens, toxin neutralization, immune response, and onco-suppression. Disruption in the interactions among the gut microbiota, intestinal epithelium, and the host immune system are associated with gastrointestinal disorders, neurodegenerative diseases, metabolic syndrome, and cancer. Probiotic bacteria (Lactobacillus spp., Bifidobacterium spp.) have been regarded as beneficial to health and shown to play a significant role in immunomodulation and displayed preventive role against obesity, diabetes, liver disease, inflammatory bowel disease, tumor progression, and cancer.

OBJECTIVE

The involvement of gut microorganisms in cancer development and prevention has been recognized as a balancing factor. The events of dysbiosis emphasize metabolic disorder and carcinogenesis. The gut flora potentiates immunomodulation and minimizes the limitations of usual chemotherapy. The significant role of prebiotics and probiotics on the improvement of immunomodulation and antitumor properties has been considered.

METHODS

I had reviewed the literature on the multidimensional activities of prebiotics and probiotics from the NCBI website database PubMed, Springer Nature, Science Direct (Elsevier), Google Scholar database to search relevant articles. Specifically, I had focused on the role of prebiotics and probiotics in immunomodulation and cancer prevention.

RESULTS

Prebiotics are the nondigestible fermentable sugars that selectively influence the growth of probiotic organisms that exert immunomodulation over the cancerous growth. The oncostatic properties of bacteria are mediated through the recruitment of cytotoxic T cells, natural killer cells, and oxidative stress-induced apoptosis in the tumor microenvironment. Moreover, approaches have also been taken to use probiotics as an adjuvant in cancer therapy.

CONCLUSION

The present review has indicated that dysbiosis is the crucial factor in many pathological situations including cancer. Applications of prebiotics and probiotics exhibit the immune-surveillance as oncostatic effects. These events increase the possibilities of new therapeutic strategies for cancer prevention.

Structure-activity relationship of Citrus segment membrane RG-I pectin against Galectin-3: The galactan is not the only important factor

Rhamnogalacturonan I (RG-I) pectin are regarded as strong galectin-3 (Gal-3) antagonist because of galactan sidechains. The present study focused on discussing the effects of more structural regions in pectin on the anti-Gal-3 activity. The water-soluble pectin (WSP) recovered from citrus canning processing water was categorized as RG-I pectin. The controlled enzymatic hydrolysis was employed to sequentially remove the α-1,5-arabinan, homogalaturonan and β-1,4-galactan in WSP. The Gal-3-binding affinity KD (kd/ka) of WSP and debranched pectins were calculated to be 0.32 μM, 0.48 μM, 0.56 μM and 1.93 μM. Moreover, based on the more sensitive cell line (MCF-7) model, the IC₃₀ value of WSP was lower than these of modified pectins, indicating decreased anti-Gal-3 activity. Our results suggested that the total amount of neutral sugar sidechains, the length of arabinan and cooperation between HG and RG-I played important roles in the anti-Gal-3 activity of WSP, not the Gal/Ara ratio or RG-I/HG ratio. These results provided a new insight into structure-activity relationship of citrus segment membrane RG-I as a galectin-3 antagonist and a new functional food.

Extraction Methods Affect the Structure of Goji (Lycium barbarum) Polysaccharides

Polysaccharides are considered to be the most important active substances in Goji. However, the structure of polysaccharides varies according to the extraction methods applied, and the solution used to prepare Goji polysaccharides (LBPs) were limited. Thus, it is important to clarify the connection between extraction methods and structure of Goji polysaccharide. In view of the complex composition of cell wall polysaccharides and the various forms of interaction, different extraction methods will release different parts of the cell wall. The present study compared the effects of different extraction methods, which have been used to prepare different types of plant cell wall polysaccharides based on various sources, on the structure of cell-wall polysaccharides from Goji, by the single separate use of hot water, hydrochloric acid (0.4%) and sodium hydroxide (0.6%), at both high and low temperatures. Meanwhile, in order to explore the limitations of single extraction, sequential extraction methods were applied. Structural analysis including monosaccharide analysis, GPC-MALLS, AFM and ¹H-NMR suggested the persistence of more extensively branched rhamnogalacturonan I (RG-I) domains in the procedures involving low-temperature-alkali, while procedures prepared by high-temperature-acid contains more homogalacturonan (HG) regions and results in the removal of a substantial part of the side chain, specifically the arabinan. A kind of acidic heteropolysaccharide was obtained by hot water extraction. SEC-MALLS and AFM confirmed large-size polymers with branched morphologies in alkali-extracted polysaccharides. Our results provide new insight into the extraction of Goji polysaccharides, which differ from the hot water extraction used by traditional Chinese medicine.

Structurally Different Pectic Oligosaccharides Produced from Apple Pomace and Their Biological Activity In Vitro

This study set out to identify the composition and the biological activity of pectin-derived oligosaccharides (POS) generated from mild acid or enzymatic hydrolysis of apple pomace (AP). The effect of the polymerization of the structural units of POS contained in the AP hydrolysate on the growth and metabolism of microbiota from the human gastrointestinal tract and the adhesion of lactic acid bacteria (LAB) or pathogens to human gut epithelial cells was investigated in vitro. Mild acid hydrolysis followed by pectinolysis with Rohapect MaPlusT yielded the highest concentration of POS. In contrast, pure enzymatic processing of the AP performed with a mixed preparation of cellulase and Rohapect MaPlusT resulted in 1.8-fold lower overall POS. The concentration of higher-order oligosaccharides (degree of polymerization (DP) 7–10), however, was 1.7-fold higher. The increased ratio of higher-order oligosaccharides caused an increase in the bifidogenic effect, as well as affecting the amount and nature of short-chain fatty acid produced. Inhibition of Enterobacteriaceae was also observed. The strongest stimulation of LAB adhesion to the human epithelial cells occurred in the presence of the preparation containing the highest concentration of higher-order oligosaccharides. The fecal bacteria and pathogens showed much weaker adhesion to intestinal cells in the presence of all the tested AP hydrolysates. Both of the tested POS preparations, containing structurally different oligosaccharides (DPs 2–10 with different ratios of higher-order oligosaccharides), have the potential to be used as prebiotics for humans and animals. They stimulate bowel colonization with lactic acid bacteria and inhibit the development of infections caused by pathogens.

Glycan utilisation system in Bacteroides and Bifidobacteria and their roles in gut stability and health

Gut residential hundred trillion microbial cells are indispensable for maintaining gut homeostasis and impact on host physiology, development and immune systems. Many of them have displayed excellence in utilising dietary- and host-derived complex glycans and are producing useful postbiotics including short-chain fatty acids to primarily fuel different organs of the host. Therefore, employing individual microbiota is nowadays becoming a propitious target in biomedical for improving gut dysbiosis conditions of the host. Among other gut microbial communities, Bacteroides and Bifidobacteria are coevolved to utilise diverse ranges of diet- and host-derived glycans through harmonising distinct glycan utilisation systems. These gut symbionts frequently share digested oligosaccharides, carbohydrate-active enzymes and fermentable intermediate molecules for sustaining gut microbial symbiosis and improving fitness of own or other communities. Genomics approaches have provided unprecedented insights into these functions, but their precise mechanisms of action have poorly known. Sympathetic glycan-utilising strategy of each gut commensal will provide overview of mechanistic dynamic nature of the gut environment and will then assist in applying aptly personalised nutritional therapy. Thus, the review critically summarises cutting edge understanding of major plant- and host-derived glycan-utilising systems of Bacteroides and Bifidobacteria. Their evolutionary adaptation to gut environment and roles of postbiotics in human health are also highlighted.

Potential prebiotics and their transmission mechanisms: Recent approaches

Prebiotics are non-digestible carbohydrates which can be used as prime source of energy for gut microflora. These can be naturally occurring in fruit and vegetables or can be made synthetically by enzymatic digestions. New versatile sources of prebiotics had been found nowadays for economic commercialization. This review will decipher on highlighting the importance of prebiotics in immunomodulation and nutrient absorption abilities of gut, as it is important for the anti-effective capacity of the organism especially in the neonatal period. Moreover, new prebiotics transmission strategies with higher penetrating capacity such as microencapsulation and immobilization have been discussed. In addition to this, literature had shown the modulation of gut microflora by the continuous use of prebiotics in many disorders so here, the role of prebiotics in health-related issues such as diabetes and inflammatory bowel disease (IBS) have been explained.

Potential Industrial Applications and Commercialization of Microalgae in the Functional Food and Feed Industries: A Short Review

Bioactive compounds, e.g., protein, polyunsaturated fatty acids, carotenoids, vitamins and minerals, found in commercial form of microalgal biomass (e.g., powder, flour, liquid, oil, tablet, or capsule forms) may play important roles in functional food (e.g., dairy products, desserts, pastas, oil-derivatives, or supplements) or feed (for cattle, poultry, shellfish, and fish) with favorable outcomes upon human health, including antioxidant, anti-inflammatory, antimicrobial, and antiviral effects, as well as prevention of gastric ulcers, constipation, anemia, diabetes, and hypertension. However, scale up remains a major challenge before commercial competitiveness is attained. Notwithstanding the odds, a few companies have already overcome market constraints, and are successfully selling extracts of microalgae as colorant, or supplement for food and feed industries. Strong scientific evidence of probiotic roles of microalgae in humans is still lacking, while scarce studies have concluded on probiotic activity in marine animals upon ingestion. Limitations in culture harvesting and shelf life extension have indeed constrained commercial viability. There are, however, scattered pieces of evidence that microalgae play prebiotic roles, owing to their richness in oligosaccharides-hardly fermented by other members of the intestinal microbiota, or digested throughout the gastrointestinal tract of humans/animals for that matter. However, consistent applications exist only in the dairy industry and aquaculture. Despite the underlying potential in formulation of functional food/feed, extensive research and development efforts are still required before microalgae at large become a commercial reality in food and feed formulation.