β-glucan, homopolymers of glucose, are found abundantly in various microorganisms, mushrooms, and plants. These β-glucan are of the high value of attention because of their bioactivity and medicinal benefits. Multiple studies show that β-glucan have the potential to enhance the immune system. However, the β-glucan from different sources have different modulating effects. It depends upon the primary chemical structure of β-glucan. One crucial source of β-glucan is yeast, especially baker’s yeast (Saccharomyces cerevisiae). The yeast-derived β-glucan, (1,3)-β-linked with small chains of (1,6)-β-linked side chains, are known for their immune-modulating effect (Chan et al., 2009).
The extraction of yeast β-glucan is an essential step for its use as a supplement to boost the immune system. The extraction method plays a vital role in determining the structure, quality, and function of β-glucan. Several isolation processes of isolation of β-glucan exist, including base, acid or combination of acid-base method, enzymatic and oxidative extraction, etc. (Borchani et al., 2014). Some of the important methods use for β-glucan extraction from yeast are briefly discussed here.
Yeast β-glucan extraction process
Yeast β-glucan is mainly alkali-insoluble glucan, which is an active polysaccharide. The key to its preparation is to remove impurities such as protein, mannan, and lipids. The methods for preparing yeast glucan in China and abroad mainly include the acid-base method, enzymatic method, and oxidative extraction.
In autolysis, cell endo-structure degrades and releases vascular proteases into the cytoplasm. The base (NaOH) helps remove impurities, while the acetic acid is a mild acid that limits the hydrolysis of (1,3)-β-glucan.
The dry active yeast cell propagated and mixed with five times 1 M NaOH. The samples were then heated in the water bath to lyse the yeast cell to release the glucan. NaOH lysed the yeast cell and helped in the release of β-glucan. The end product of the pellet is air-dried to obtain pure β-glucan and stored for future use.
Advantages and disadvantages of this method
The use of a strong base (NaOH) and weak acid (CH3COOH) give a high quality and high quantity beta-glucan. The glucan extraction through this method is easy, fast, economical, and has promising results. The acid-base method has certain advantages; it yields small size, uniform, non-agglomeration, and high yield of β-glucan. Furthermore, it gives the triple-helical structure of β-1,3/1,6-linked glucans with high thermal stability. The acid-base method is efficient regarding the outcome. Although this method provides high-purity glucan products, it needs to consume many acids and alkali, causing severe environmental pollution, causing specific damage to glucan molecules (Mahmoud Amer et al., 2021).
The working principle of the enzymatic method is based on yeast cell lysis is by using cell autolysis and hot water. Subsequently, lyticase enzyme is used for the removal of cell wall proteins. Protease enzyme is also used to remove cell wall proteins and organic solvents for lipid removal (Varelas et al., 2016).
Yeast cells are harvested and disrupted in a high-pressure homogenizer. Subsequently, treating with hot water a gentle sonication is greatly helpful in breaking yeast cells, following that β-glucan extracted from yeast cells by combination of hot water and enzymatic treatment. Enzyme treatment of the yeast cell wall can remove a large amount of protein, thereby reducing the subsequent alkali concentration and usage (Jaehrig et al., 2008). Addition of lyticase enzyme help in the removal of cell wall protein. Protease enzyme is also helpful in the removal of cell wall protein and organic solvents. The enzymatic method of beta-glucan extraction gave a better yield and higher content than did traditional isolation methods.
Advantages and disadvantages of this method
This method is more sophisticated, and the resulting yeast β-glucan product has a complete molecular structure. Therefore, the enzyme method is more suitable for large-scale yeast β-glucan extraction and purification (Borchani et al., 2014). The disadvantage of this method is the instability and high cost of the enzyme.
In addition to the traditional acid-base method and enzymatic method, some researchers also use other methods to prepare yeast glucan with higher purity. 0.5%~2% sodium hypochlorite solution to directly treat the yeast cell wall for more than 5 hours at room temperature, and the yield of the high-purity yeast glucan product obtained was more than 20%. Although this method can obtain yeast β-glucan with higher purity, the influence of strong oxidants on the molecular structure of glucan remains to be studied in depth (Ohno et al., 1999).
Hiyeast uses the acid-base method, and their product has been proven by research.
Hiyeast uses the Acid-base method for extraction and preparation of Beta-Glucan from yeast. They did various research trials for the determination of quality and effects on animals. Hiyeast’s check its product by a variety of research on the animal. They did the clinical trials on mice and tested them in the following items.
NK cell activity test on mice
The result shows that their yeast beta-glucan product can strengthen the NK cells of the tested animal to increase immunity significantly. This study confirms that the use of beta-glucan substantially enhances immunity. Hence, many people will pay attention to use β-glucan in their foods to improve their immune system in the future.
They made a one-month yeast β-glucan trial on mice. The mice were fed for 30 consecutive days, and the results showed that the sample was non-toxic, non-mutagenic, or mutagenic. A high dose of yeast β-glucan significantly enhances the antibody level of mice, and thus it promotes humoral immunity, and no toxic or mutagenic effect was observed.
These studies show that their β-glucan products are according to international standards and prepared using highly efficient methods. Their methods are well-known and reliable, which provide high-quality non-toxic, non-mutagenic products that will significantly enhance the immune system. The company is committed to delivering high-standard β-glucan products to help people in boosting their immune systems.