2.1.1.2. Yeasts and fungi β-glucans

Another pivotal property of fungi/yeasts β-glucans is the modulation of the immune system [27, 28]. This effect could be due to the ability of β-glucans to stimulate receptors of the innate immune system present in the membrane of enterocytes, M cells and dendritic cells, improving the phagocytic activity of macrophages and antimicrobial activity of mononuclear cells and neutrophils [29–31]. This type of β-glucans would also prevent the promotion and progression of certain types of cancer, acting synergistically with monoclonal antibodies and chemotherapy [32, 33]. This stimulation of immunity would be achieved by increasing the secretion of pro-inflammatory cytokines and chemokines [34]. The main receptor involved in the effect of B-glucans immunity is Dectin-1, even though there is also a role for the receptor 3 of the complement, TLR-2, TLR-6 and the "scavengers" receptors [35, 36]. Dectin-1, known in human beings as β-glucans receptor (βGR), is a member of the pattern recognition receptors (PRR) which fulfill an essential role in the innate immune response against viruses, bacteria, yeasts, and fungi, contributing to the recognition and elimination of pathogens [34]. This receptor is highly expressed in immune cells such as dendritic cells, neutrophils, eosinophils, and monocytes as well as in some populations of T and B cells and, to a lesser extent, in macrophages and enterocytes [31, 34, 35]. Dectin-1 acts through signal transduction activating Syk and RAF-1 [14]. It can also act synergistically with TLR which mediates the production of proinflammatory cytokines, such as IL-12 and TNF-α [33, 35].

compounds, during the metabolism of the colon bacteria that transform them into lignans of

New Insights into Alleviating Diabetes Mellitus: Role of Gut Microbiota and a Nutrigenomic Approach

http://dx.doi.org/10.5772/intechopen.76202

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Mucilage is water-soluble polysaccharide present in many seeds, capable of absorbing 60–100 times their weight in water forming gels. They are formed by ramified arabinoxylans chains [44]. The mucilage is similar to the gums, composed of galactose, mannose, xylose, and other sugars [45]. One of the best known mucilage is psyllium (psyllium) or also called plantain, coming from the seeds of Plantago genus [42, 44]. The mucilage extracted from algae contains sugars somewhat different from terrestrial vegetables, such as agarobiose in the agar and sulfsugar in the carrageenan, used in food technology [44]. Flaxseed mucilage is a complex polydisperse hydrocolloid and the different rheological behaviors observed in cultivars are caused by the differences in the ratio between neutral and acid polymers and by the molecular

Even though flaxseed is much known, it is not widely used in the formulation of food [47]. This seed has significant amounts of bioactive compounds, such as alpha-linolenic acid, lignans and dietary fiber, with potential effects in the prevention of some chronic diseases such as reducing the risk of cardiovascular diseases, mitigating the effects of diabetes, renal pathologies, obesity, colon and rectum cancer, reducing serum cholesterol level, and promoting the intestinal evacuation [46, 47]. These characteristics make flaxseed an attractive source of ingredients to

Different in vitro and in vivo studies have demonstrated the ability of kefir to promote health through the presence of bioactive peptides. Multiple bioactivities of this beverage such as antihypertensive, antimicrobial, immune-modulating, mineral-carrying, antithrombotic, opioid, and antioxidant have been the most reported [49]. These characteristics of kefir, along to the pre- and probiotic properties, hypocholesterolemic, the bioavailability of milk components with biological activity and the presence of metabolites such as organic acids and bacteriocins, situate it as functional food [50]. This is a food that beyond the nutritional contribution of its components has been proven to benefit one or more physiological functions of the organism, improving the health, well-being, and/or reducing the risk to suffer diseases [51–53]. Additionally, there are bioactivities that have been poorly studied as the mineral fixing properties and the antithrombotic activity. There are some studies about the substrate-microorganismmetabolite-bioactivity inter-relationships based on metagenome studies [54, 55]. It would be important to carry out more investigations to determine the different bioactivities more deeply and the effective dose by trying to reach the intestinal level in sufficient quantity to implant

weight and structural conformation of polysaccharides [45, 46].

be used in the elaboration of different functional foods [48].

mammals [42, 43].

2.1.3.2. Mucilage

2.1.3.3. Flaxseed

2.1.4. Kefirs

and colonize its surface [56].

#### 2.1.2. Fructo-oligosaccharides

Inulin is a non-digestible carbohydrate present in many vegetables, fruits, and cereals [36]. Currently, at the industrial level it is extracted from the chicory root (Cichorium intybus) and is widely used as an ingredient in functional foods. Inulin and its derivatives (oligofructose, fructo-oligosaccharides) are generally called fructans, basically composed of linear chains of fructose [37]. The maximum dose allowed to be added to food formulated with inulin is up to 20 g/day for a simple dose and up to 10 g/day for multiple doses. At higher doses it can cause intolerances after consumption, such as osmotic effects (diarrhea), intestinal noises and flatulence as a result of the fermentation process [38]. Oligofructose is obtained by the partial enzymatic hydrolysis of inulin, composed of linear chains of glucosyl-fructosil. GP ranges between 2 and 8, with an average value of approximately [37]. It is present in foods such as cereals, onions, garlic, banana, and corn [38, 39]. There are promising evidences of its performance in the regulation of lipid parameters, reduction of the risk of cancer, reinforcement of the immune response and protection against intestinal disorders [40]. In a wide variety of food products, inulin and its derivatives are used as: thickener, emulsifier, gelling agent, sugar and fat substitute, moisturizer, depressor of the freezing point [37, 39].
