Recent approaches for the quantitative analysis of functional oligosaccharides used in the food industry: A review

A chemo-enzymatic pathway to expand cellooligosaccharide chemical space through amine bond introduction

Enzymatic functionalization of oligosaccharides is a useful and environmentally friendly way to expand their structural chemical space and access to a wider range of applications in the health, food, feed, cosmetics and other sectors. In this work, we first tested the laccase/TEMPO system to generate oxidized forms of cellobiose and methyl β-D-cellobiose, and obtained high yields of novel anionic disaccharides (>60 %) at pH 6.0. Laccase/TEMPO system was then applied to a mix of cellooligosaccharides and to pure D-cellopentaose. The occurrence of carbonyl and carboxyl groups in the oxidation products was shown by LC-HRMS, MALDI-TOF and reductive amination of the carbonyl groups was attempted with p-toluidine a low molar mass amine to form the Schiff base, then reduced by 2-picoline borane to generate a more stable amine bond. The new grafted products were characterized by LC-HRMS, LC-UV-MS/MS and covalent grafting was evidenced. Next, the same procedure was adopted to successfully graft a dye, the rhodamine 123, larger in size than toluidine. This two-step chemo-enzymatic approach, never reported before, for functionalization of oligosaccharides, offers attractive opportunities to anionic cellooligosaccharides and derived glucoconjugates of interest for biomedical or neutraceutical applications. It also paves the way for more environmentally-friendly cellulose fabric staining procedures.

Human milk oligosaccharides and the association with microbiota in colostrum: a pilot study

HMOs (Human milk oligosaccharide) has an impact on maternal and infant health. Colostrum samples of 70 breastfeeding women in China were collected and recorded clinical characteristics. The major oligosaccharides and microbiota were quantitated in colostrum. The concentration of fucosylated HMOs in primipara was higher than that of multipara (p = 0.030). The concentration of N-acetylated HMOs in vaginal delivery milk was less than that of cesarean (p = 0.038). Non-fucosylated HMOs of breastfeeding women were less than that of breast pump (p = 0.038). Meanwhile, the concentration of LNT was positively correlated with Lactobacillus (r = 0.250, p = 0.037). DS-LNT was negatively correlated with Staphylococcus (r = - 0.240, p = 0.045). There was a positive correlation of Streptococcus with LNFP II (r = 0.314, p = 0.011) and 3-SL (r = 0.322, p = 0.009). In addition, there was a negative correlation between 2'-FL and 3-FL (r = - 0.465, p = 0.001). There was a positive correlation between LNT and LNnT (r = 0.778, p = 0.001). Therefore, the concentration of HMOs is related to number of deliveries, delivery mode, lactation mode and perinatal antibiotic. The concentration of HMOs is related to Lactobacillus, Streptococcus and Streptococcus in colostrum. In addition, there are connections between different oligosaccharides in content. The study protocol was also registered in the ClinicalTrails.gov (ChiCTR2200064454) (Oct. 2022).

Purification and identification of oligosaccharides from Cimicifuga heracleifolia Kom. rhizomes

Even though Cimicifuga sp. is widely used in functional foods around the world, the content and structure of its oligosaccharides remain unclear. Here, we isolated a mixture of oligosaccharides from Cimicifuga heracleifolia Kom. rhizomes with a yield of 9.5% w/w. Twenty-six oligosaccharide monomers from the mixture were purified using optimized SEC and HILIC techniques. The oligosaccharides were identified as belonging to two groups by using HPAEC-PAD, MALDI-TOF-MS, NMR and GC-MS methylation analyses. One group belongs to sucrose and inulin type fructo-oligosaccharides (FOS) {β-d-Fruf-(2 → 1)-[β-d-Fruf-(2 ↔ 1)]_n=1-12-α-d-Glcp} with a 3-14 degree of polymerization (DP). Oligosaccharides in the other group belong to the inulo-n-ose type FOS {β-d-Fruf-(2 → 1)-[β-d-Fruf-(2 → 1)]_m=0-12-β-d-Frup} with a DP of 2-14. This appears to be the first time that these oligosaccharides have been purified from Cimicifuga heracleifolia Kom., thus providing useful information concerning the utilization of Cimicifuga heracleifolia Kom. in functional foods.

Natural antimicrobial oligosaccharides in the food industry

An increase in the number of antibiotic resistance genes burdens the environment and affects human health. Additionally, people have developed a cautious attitude toward chemical preservatives. This attitude has promoted the search for new natural antimicrobial substances. Oligosaccharides from various sources have been studied for their antimicrobial and prebiotic effects. Antimicrobial oligosaccharides have several advantages such as being produced from renewable resources and showing antimicrobial properties similar to those of chemical preservatives. Their excellent broad-spectrum antibacterial properties are primarily because of various synergistic effects, including destruction of pathogen cell wall. Additionally, the adhesion of harmful microorganisms and the role of harmful factors may be reduced by oligosaccharides. Some natural oligosaccharides were also shown to stimulate the growth probiotic organisms. Therefore, antimicrobial oligosaccharides have the potential to meet food processing industry requirements in the future. The latest progress in research on the antimicrobial activity of different oligosaccharides is demonstrated in this review. The possible mechanism of action of these antimicrobial oligosaccharides is summarized with respect to their direct and indirect effects. Finally, the extended applications of oligosaccharides from the food source industry to food processing are discussed.

Sustainable Food Systems: The Case of Functional Compounds towards the Development of Clean Label Food Products

The addition of natural components with functional properties in novel food formulations confers one of the main challenges that the modern food industry is called to face. New EU directives and the global turn to circular economy models are also pressing the agro-industrial sector to adopt cradle-to-cradle approaches for their by-products and waste streams. This review aims to present the concept of “sustainable functional compounds”, emphasizing on some main bioactive compounds that could be recovered or biotechnologically produced from renewable resources. Herein, and in view of their efficient and “greener” production and extraction, emerging technologies, together with their possible advantages or drawbacks, are presented and discussed. Μodern examples of novel, clean label food products that are composed of sustainable functional compounds are summarized. Finally, some action plans towards the establishment of sustainable food systems are suggested.

Application of oligosaccharides in meat processing and preservation

In recent decades, consumer preference and attention to foodstuff presented as healthy and with desirable nutritional information, has increased significantly. In this field, the meat industry has a challenging task since meat and meat products have been related to various chronic diseases. Functional ingredients have emerged in response to the increasing demand for healthier and more nutritious foods. On this matter, oligosaccharides such as fructooligosaccharides (FOS), xylooligosaccharides (XOS), galactooligosaccharides (GOS), and chitooligosaccharides (COS) have been presented as suitable ingredients for the meat industry with the aim of obtaining healthier meat derivatives (e.g. with low fat or sugar content, reduced amount of additives, and desirable functional properties, etc.). However, studies considering application of such oligomers in the meat sector are scarce. In addition, a large number of issues remain to be solved related both to obtaining and characterizing the oligosaccharides available in the industry and to the effect that these ingredients have on the features of meat products (mainly physicochemical and sensory). The study of new oligosaccharides, the methodologies for obtaining them, and their application to new meat products should be promoted, as well as improving knowledge about their effects on the properties of functional meat foods.

Characterization of Buritirana (Mauritiella armata) Fruits from the Brazilian Cerrado: Biometric and Physicochemical Attributes, Chemical Composition and Antioxidant and Antibacterial Potential

The buritirana is a little-explored species of the Arecaceae family. The biometric and physicochemical characteristics, nutritional and chemical composition and antioxidant and antibacterial potential of the buritirana fruit fractions were evaluated here for the first time. The fruits presented an oblong shape. The pulp represented 16.58% of the whole-fruit weight (10.07 g). The moisture, ash and soluble fiber contents were similar for the whole fraction without seed (WS) and pulp. Although the total carbohydrate content was the same for seed and peel (23.24 g·100 g⁻¹), the seed showed higher protein and insoluble fiber contents. Except for glucose (1256.63 mg·100 g⁻¹), the seed showed the highest concentrations of mono-, di- and oligosaccharides. Mineral content ranged from 0.43 to 800 mg·100 g⁻¹ in all fractions. The peel fraction showed the highest content of vitamin C. The physicochemical results indicate the pulp and WS fraction have potential for the production of fruit-derived food products. Protocatechuic and quinic acids and epicatechin/catechin were found in all fractions. The assay antioxidant capacity DPPH, phenolic content and total flavonoids were higher in the pulp; TEAC and ORAC_HF values were lower in the seed. Volatile organic compounds were not identified, and the fractions did not show antibacterial activity.

Changes in HMO Concentrations throughout Lactation: Influencing Factors, Health Effects and Opportunities

Human milk oligosaccharides (HMOs) are important functional biomolecules in human breast milk. Understanding the factors influencing differences in HMO composition and changes in their concentration over lactation can help to design feeding strategies that are well-adapted to infant's needs. This review summarises the total and individual concentration of HMOs from data published from 1999 to 2019. Studies show that the HMO concentrations are highest in colostrum (average 9-22 g/L), followed by slightly lower concentrations in transitional milk (average 8-19 g/L), with a gradual decline in mature milk as lactation progresses, from 6-15 g/L in breast milk collected within one month of birth, to 4-6 g/L after 6 months. Significant differences in HMO composition have been described between countries. Different HMOs were shown to be predominant over the course of lactation, e.g., 3-fucosyllactose increased over lactation, whereas 2'-fucosyllactose decreased. Recent clinical studies on infant formula supplemented with 2'-fucosyllactose in combination with other oligosaccharides showed its limited beneficial effect on infant health.