Chapter 1: Theory of the Yeast Beta Glucan Assay Procedure
Chapter 2: Kit Components
Chapter 3: Preparation of Reagents
Chapter 4: Preparation of other Reagents required
Chapter 5: Measurement of 1, 3:1, 6-Beta-Glucan in Yeast Preparations
Chapter 6: Calculations
50 assays per kit
Prices exclude VAT
Available for shipping
|Content:||50 assays per kit|
Short term stability: 2-8oC,
Long term stability: See individual component labels
|Stability:||> 2 years under recommended storage conditions|
|Limit of Detection:||1 g/100 g|
|Reaction Time (min):||~ 100 min|
|Application examples:||Yeast preparations and other materials|
|Method recognition:||Novel method|
Enzymatic Yeast Beta-Glucan test kit, an enzymatic procedure for the measurement and analysis of 1,3:1,6-β-glucan in yeast. Also measures 1,3-β-glucan.
- Very competitive price (cost per test)
- All reagents stable for > 12 months after preparation
- Mega-Calc™ software tool is available from our website for hassle-free raw data processing
- Standard included
Ishida, Y., Ohta, K., Naruse, T., Kato, H., Fukui, A., Shigeishi, H., Nishi, H., Kei Tobiume, K. & Takechi, M. (2018). Infection and Immunity, IAI-00575.
Oral keratinocytes provide the first line of host defense against oral candidiasis. We speculated that interactions of fungal cell wall components with oral keratinocytes regulate stress response against Candida infection, and examined the expression of genes induced by heat-killed Candida albicans in oral immortalized keratinocytes using a cDNA microarray technique. Of 24,000 genes revealed by that analysis, we focused on HO-1, a stress-inducible gene, as its expression was increased by both heat-killed as well as live C. albicans. In histological findings, HO-1 expression in the superficial layers of oral epithelium following Candida infection was elevated as compared to healthy epithelium. We then investigated fungal cell wall components involved in induction of HO-1 expression and found that β-glucan-containing particles (β-GPs) increased tha expression. Furthermore, β-glucan was observed on the surface of both heat-killed C. albicans and Candida that has invaded oral epithelium. Fungal β-GPs also promoted induction of intracellular reactive oxygen species (ROS), NADPH oxidase activation, and p38 MAPK phosphorylation, while those specific inhibitors inhibited HO-1expression induced by fungal β-GPs. Moreover, fungal β-GPs induced Nrf2 translocation into nuclei via p38MAPK signaling, while HO-1 expression induced by fungal β-GPs was inhibited by Nrf2 siRNA. Finally, knockdown of cells by HO-1 and Nrf2 siRNAs resulted in increased β-GPs-mediated ROS production as compared to the control cells.Hide Abstract
Sharma, S., Saxena, D. C. & Riar, C. S. (2018). Journal of Food Measurement and Characterization, 12(2), 1186-1194.
β-Glucan is a fibrous polysaccharide and good source of soluble dietary fiber having multiple functional and medicinal properties. Functionality of β-glucan extracts was investigated followed by studying the characteristics of cakes containing 2.5-7.5% of this extracts. Yield, purity, foaming ability, DPPH activity, WBC and SP β-glucan extracts of germinated millets improved due to germination. The in vitro antioxidant activity of cake increased from 18.23 to 22.58% with increase in β-glucan level from 2.5 to 7.5%. The volume index of cake was improved with β-glucan addition up to 5.0% and decreased with further addition to 7.5%. TPA characteristics of the cake improved significantly with β-glucan addition where as firmness decreased with increase in β-glucan content. Panelists rated highly cake fortified with β-glucan levels up to 5.0%. The decrease in sensory score at higher β-glucan level could be attributed to the increase in gumminess, cohesiveness and decrease in resilience score. The L and b values of cake crust and crumbs decreased significantly whereas ‘a’ value increased significantly with increase in β-glucan levels. Overall, the addition of up to 5.0% β-glucan extract in wheat flour cake improved its physicochemical, textural, sensory and in vitro antioxidant characteristics.Hide Abstract
Aguiló-Aguayo, I., Walton, J., Viñas, I. & Tiwari, B. K. (2017). LWT-Food Science and Technology, 77, 92-99.
The effect of ultrasound technology to extract the water soluble polysaccharides from dried and milled by-products generated from Agaricus Bisporus production was studied. Amounts of β-glucan 1.01 and 0.98 g/100 g dry mass were obtained in particle sizes of 355-250 µm and 150-125 µm from the mushroom by-products. Three parameters of extraction were studied; extraction time (0-15 min), ultrasonic amplitude (20-100 µm) and precipitation time (1 or 18 h). The application of ultrasounds enhanced the extraction polysaccharide yields compared to the untreated samples. The highest extraction yield of 4.7% was achieved with an extraction time of 15 min, maximum amplitude of 100 µm with 1 h of precipitation in 80% ethanol. The coefficient of determinations for predicted water soluble polysaccharides extraction yields showed good correlation with the experimental data at the 95% confidence level and indicated that the non-exponential Peleg's model could be employed to predict the extraction polysaccharide yields after ultrasound treatment.Hide Abstract
Kolundžić, M., Stanojković, T., Radović, J., Tačić, A., Dodevska, M., Milenković, M., Sisto, F., Masia, C., Farronato, G., Nikolić, V. & Kundaković, T. (2017). Journal of Medicinal Food, 20(8), 790-796.
Antibacterial and cytotoxic activities of cyclohexane, dichloromethane, methanol, and aqueous extracts of Cantharellus cibarius were tested. Broth microdilution assay was performed against 10 bacterial strains (Staphylococcus aureus, S. epidermidis, Micrococcus luteus, Bacillus subtilis, Enterococcus feacalis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella abony), with emphasis on Helicobacter pylori. Methanol extract was the most active against H. pylori strains with minimal inhibitory concentration values between 4 and 32 µg/mL. All extracts were active against antibiotic resistant H. pylori. Methanol and aqueous extracts had no cytotoxicity against tested cell lines, whereas cyclohexane and dichloromethane extracts were active against HeLa and N87 cells, but also against healthy MRC-5 cells (IC50 39.26 ± 1.24-134.79 ± 0.01 µg/mL). The tested aqueous extracts have shown 68% of angiotensin-converting enzyme inhibitory activity in doses of 1.25 mg/mL. Chemical analysis has shown the presence of linoleic, cis-vaccenic, and oleic acids, sterols, β-glucans, and polyphenolic compounds.Hide Abstract
Narwal, S., Kumar, D., Sheoran, S., Verma, R. P. S. & Gupta, R. K. Journal of Food Science and Technology, 54(9), 2638-2644.
In this study, efforts were made to utilize hulless barley (variety BHS352) to enhance the nutritive value of chapatti and biscuit made from wheat flour. Barley flour was added to wheat flour in different ratios (5 to 30%). Antioxidant activity, total phenolic content and β-glucan content were determined both in flour blends and their products. Changes in physical quality and taste of chapatti and biscuits after blending of hulless barley flour with wheat flour were measured. The chapatti quality score decreased by 15% and biscuit spread factor by 33% after 30% barley flour blending. Significant increase in β-glucan content and antioxidant activity of flour blends and their products was observed at 30% blending level. The phenolic content increased from 63 to 135 µg for biscuits and 237 to 287 µg GAE/g for chapatti with blending of 30% barley flour.Hide Abstract
Martins, Z. E., Pinho, O. & Ferreira, I. M. P. L. V. O. (2017). Journal of Food Science, 82(9), 2183-2191.
The use of agroindustry by-products (BP) for fortification of wheat bread can be an alternative to waste disposal because BP are appealing sources of dietary fiber. Moreover, it may also contribute to indirect income generation. In this study, sensory, color, and crumb structure properties of breads fortified with fiber rich fraction recovered from four types of agroindustry BP were tested, namely orange (OE), pomegranate (PE), elderberry (EE), and spent yeast (YE). Statistical models for sensory preference evaluation and correlation with color and crumb structure were developed. External preference mapping indicated consumer preferences and enabled selection of the concentrations of BP fibre-rich fraction with best acceptance, namely 7.0% EE, 2.5% OE, 5.0% PE, and 2.5% YE. Data collected from image analysis complemented sensory profile information, whereas multivariate PLS regression provided information on the relationship between “crust color” and “crumb color” and instrumental data. Regression models developed for both sensory attributes presented good fitting (R2Y > 0.700) and predictive ability (Q2 > 0.500), with low RMSE. Crust and crumb a* parameters had a positive influence on “crust color” and “crumb color” models, while crust L* and b* had a negative influence.Hide Abstract
Park, M. & Kim, M. (2017). Preventive Nutrition and Food Science, 22(4), 365371.
In this study, the crude ethanol Rhynchosia nulubilis cultivated with Ganoderma lucidummycelium (RNGM) extract was solvent fractionated with organic solvents such as n-hexane, chloroform, ethyl acetate, and water. The anticancer activities, anti-inflammatory activity total polyphenols, total flavonoids, isoflavones, and β-glucan of the solvent fractions of RNGM were studied. The ethyl acetate fraction showed the highest 2,2-diphenyl-1-picrylhydrazyl scavenging activity of 76.60% at 800 µg/mL. The ethyl acetate fraction also showed higher antioxidant activity in 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and ferric reducing ability of plasma assays compared to the other fractions. In addition, this study confirmed that the ethyl acetate fraction strongly inhibited nitric oxide production. The ethyl acetate fraction had the highest amount of total polyphenol and total flavonoid (65.33 mg gallic acid equivalent/g and 18.50 mg quercetin equivalent/g, respectively). The ethyl acetate fraction (13.02%) showed the highest amount of total β-glucan, followed by the water (6.32%), chloroform (1.43%), and n-hexane fraction (0.85%). Therefore, it is suggested that the ethyl acetate fraction of Rhynchosia nulubilis cultivated with Ganoderma lucidum mycelium may be potential natural sources for nutritional and pharmaceutical applications.Hide Abstract
Rieder, A., Ballance, S., Böcker, U. & Knutsen, S. (2017). Carbohydrate Polymers, 181, 34-42.
Due to their immunomodulatory effect, 1,3-β-G from yeast are used as functional ingredients, but reliable methods for their detection in foods are lacking. We have adapted a method based on fluorescence detection with aniline blue to quantify the amount of five commercial yeast β-glucan preparations added to crisp or yeast-leavened bread. This assay detected yeast β-glucan preparations added to different breads with an average recovery of 90, 96, 99 and 105%, while one of the preparations was overestimated, with an average recovery of 157%. The presence of cereal 1,3-1,4-β-D-glucans did not interfere with assay performance. The addition of 1,3-β-G at 0.2 and 0.5 g/100 g is low compared to the recommended dose of 1,3-β-G per serving demonstrating assay sensitivity. However, more research is needed to fully understand 1,3-β-G conformation/structure on aniline blue interaction as well as the effect of baking on structure and dissolution properties of yeast β-glucans.Hide Abstract
Pengkumsri, N., Sivamaruthi, B. S., Sirilun, S., Suwannalert, P., Rodboon, T., Prasitpuriprecha, C., Peerajan, S., Butrungrod, W. & Chaiyasut, C. (2017). RSC Advances, 7(1), 396-402.
The present study was employed to evaluate the impact of black rice bran (BRB) extract, and yeast β-glucan (YBG) supplementation on a dextran sodium sulfate (DSS)-induced colitis rat model. Serum level antioxidant enzymes, cytokines, and histopathological changes were studied by spectrophotometric, ELISA, HPLC, and microscopic analysis. The preventive effect of RB + YBG combinational treatment for DSS-induced colitis in rat was greater than that of RB extract and YBG regarding serum antioxidant level. The elevated expression of the studied inflammatory cytokines (IL-6, IL-17, IFN-γ) was effectively more attenuated by RB + YBG combinational treatment than other tested interventions, which was accompanied by an increase in anti-inflammatory cytokines (IL-10, TGF-β). The histological study supported that RB + YBG supplementation improves the health status of DSS-induced colitis rats. The results suggested that the supplementation of RB + YBG was a potent alternative nutrient based therapeutic agent for colitis and to prevent the development of cancer.Hide Abstract
Sharma, S., Saxena, D. C. & Riar, C. S. (2016). Plant Foods for Human Nutrition, 71(3), 231-238.
The study was carried out to analyze the characteristics of two functional constituents’ viz. γ-amino butyric acid (GABA) and β-glucan extracted from raw and germination barnyard millet (var. PRJ-1). A significant (P ≤ 0.05) effect of germination (sprouting) was observed in yield, chemical composition, functional, rheological and antioxidant properties of β-glucan and GABA. The yield of GABA extract was 12.34 % and the content increased from 6.37 mg/100 g in raw to 35.70 mg/100 g in germinated sample. The DPPH, total antioxidant and hydrogen peroxide scavenging activities of GABA extract increased after germination from 45.34 to 65.34 %, 15.3 to 33.3 millimole/g and 38.4 to 64.7 millimole/g, respectively. The yield of β-glucan extract of raw and germinated flour was 6.05 and 5.01 % whereas the β-glucan contents were 83.30 and 79.64 %, respectively. The functional properties of β-glucan i.e. , swelling power, water binding capacity and DPPH scavenging activity increased from 1.45 to 1.76 g/g, 2.13 to 2.32 g/g and 44.39 to 57.42 %, respectively, after germination. Similarly there was an increase in the storage modulus after germination process which attributes a better viscoelastic capacity of β-glucan at low frequencies. The results exploit that the β-glucan and GABA might promise a polymeric incipient to be implemented as food additives with variable functional and structural characteristics.Hide Abstract
Ahmad, M., Gani, A., Shah, A., Gani, A. & Masoodi, F. A. (2016). Carbohydrate Polymers, 153, 696-702.
The nutraceutical potential of β-D-glucan is largely dependent on its structure, size and viscosity. The present study analyzed the effect of germination and microwave processing of barley on the structural, size, antioxidant and thermal characteristics of β-D-glucan. The molecular weight and viscosity of β-D-glucan obtained from germinated barley (GGB) were the lowest (144 kDa and 37.33 cp) as compared to β-D-glucan from microwave processed barley (GMB) and unprocessed barley (GUB). The GGB exhibited higher antioxidant potential than GMB and GUB. The Structural elucidation by ATR-FTIR revealed scission in polymeric chain and β glycosydic linkage of β-D-glucan obtained from processed barley. The highest peak intensity at glycosydic linkage in GGB confirms more scission in the molecule. The DSC curve of GGB showed the highest transition temperature. It was concluded that germination of barley can be a good approach for enhancing the antioxidant potential of β-D-glucan.Hide Abstract
Varelas, V., Tataridis, P., Liouni, M. & Nerantzis, E. T. (2016). E-Journal of Science & Technology, 11(1).
β-D-glucan is a D-glucose biopolymer. The cell wall of yeast contains β-D-glucans. β-Glucan has been isolated from barley, oat, mushrooms, algae bacteria and yeasts. Spent brewer’s yeast has been widely used for β-glucan production but yeast waste biomass from wine industry has not been yet utilized. Yeast β-glucan can be incorporated in various functional food, beverage and pharmaceutical products. In recent years, there is an increasing interest arrived from the food and pharmaceutical research community due to its proven immunostimulating role in human and animal health. For the production and purification of yeast β-glucan various technologies have been proposed and new techniques are constantly investigated. The aim of our research was the study of three different methods and technologies for the extraction and purification of β-D-glucans from Vin 13, a S.cerevisiae strain used widely for wine production. The max. concentration (64.56 ± 1.25 %) of β-glucan in the final yeast powder was achieved with the extraction Method 3 in only two steps process and more precisely with 10% (w/v) yeast cell rehydration, 24 h yeast autolysis and 0.5 M hot NaOH. The demonstrated method is easy, fast and low cost for yeast β-glucan production in industrial scale.Hide Abstract
Walachowski, S., Tabouret, G. & Foucras, G. (2016). PloS one, 11(2), e0148464.
β-glucans (BG) are abundant polysaccharides of the Saccharomyces cerevisiae cell wall (Sc CW), an industry byproduct. They have immuno-stimulatory properties upon engagement of dectin-1 (Clec7a), their main receptor on particular immune cells, and they actually become of great interest because of their preventive or therapeutic potentials. Zymosan, a crude extract of Sc CW was studied as a prototypic BG, despite its miscellaneous PAMPs content. Here, we examined the response of murine wild type or Clec7a-/- bone marrow-derived macrophages (BMDM) to products with increasing BG content (15, 65 or 75%) and compared their effects with those of other dectin-1 ligands. The enrichment process removed TLR ligands while preserving dectin-1 activity. The most enriched extracts have very low NFκB activity and triggered low amounts of cytokine production in contrast with crude products like zymosan and BG15. Furthermore, MyD88-/- BMDM did not produce TNFα in response to crude Sc CW extracts, whereas their response to BG-enriched extracts was unaffected, suggesting that BG alone are not able to initiate cytokine secretion. Although Sc CW-derived BG stimulated the late and strong expression of Csf2 in a dectin-1-dependent manner, they remain poor inducers of chemokine and cytokine production in murine macrophages.Hide Abstract
Lee, S. H., Jang, G. Y., Kim, M. Y., Hwang, I. G., Kim, H. Y., Woo, K. S., Lee, M. J., Kim, T. J., Lee, J. & Jeong, H. S. (2015). Journal of Cereal Science, 65, 147-153.
In this study, response surface methodology was employed to optimize conditions for the extraction of barley β-glucan. A central composite experimental design was applied to investigate the effects of hydrogen peroxide concentration (X1: 0.2-0.8%), temperature (X2: 90-150°C), and time (X3: 5-35 min) on the extraction of both total and soluble β-glucan. As a result, the highest total β-glucan content was 7.52% at a peroxide concentration of 0.451%, a temperature of 120°C and an extraction time of 22 min, and this value was greatly influenced by X1 (P < 0.001). The highest soluble content was 6.31% at 0.444%, 105°C, and 21 min. This extraction was affected by X1 (P < 0.001) and X2 (P < 0.001). With increasing X1 and X2 values, β-glucan content decreased and β-glucan purity increased. Our study showed that oxidation with hydrogen peroxide followed by heat treatment is an efficient and high-yielding method for the extraction of high-purity β-glucan from barley.Hide Abstract
Kodama, S., Shoda, T., Wahyudiono, W., Machmudah, S., Kanda, H. & Goto, M. (2015). Modern Applied Science, 9(7), 220.
Subcritical water is an environmentally friendly method with a wide range of applications, such as extraction, hydrolysis, and wet oxidation of organic compounds. Here, water at subcritical conditions was applied to extract polysaccharides from Ganoderma lucidum (G. lucidum) and barley grains at 120 - 180 °C and 4.0 MPa using a semi-batch system. The liquid products were directly micronized and contacted with hot air to form microsphere particles. During extraction process, cell wall disruptions of G. lucidum and barley grains took place, allowing the removal of the polysaccharides isolating other constituents in G. lucidum and barley grains via autohydrolysis. Scanning electron microscope (SEM) images described that the particle products produced had sphere and wrinkled morphology of particles with diameters varying from 1 to 10 µm. The experimental result revealed that the particles formed from G. lucidum and barley grains extract contained 40-45% and 30-35% weight β-glucan, respectively.Hide Abstract
Lee, S. H., Jang, G. Y., Hwang, I. G., Kim, H. Y., Woo, K. S., Kim, K. J., Lee, M. J., Kim, T. J., Lee, J., Jeong, H. S. & Jeong, H. S. (2015). Preventive Nutrition and Food Science, 20(2), 110.
This study was performed to investigate changes in the content and purity, as well as physical characteristics of β-glucan extracted from acid hydrolyzed whole grain barleys. Waxy and non-waxy barleys (Hordeum vulgare) were hydrolyzed with different concentrations of HCl (0.1~0.5 N) for 1 h. As the HCl concentration increased, the contents of total and soluble β-glucan from acid hydrolyzed barley decreased. However the ratio of soluble/total β-glucan content and purities of β-glucan significantly increased. The ratio of β-(1→4)/β-(1→3) linkages, molecular weight, and viscosity of soluble β-glucan of raw barleys were 2.28~2.52, 6.0~7.0×105 g/mol, and 12.8~32.8 centipoise (cP). Those of isolated soluble β-glucan were significantly decreased to 2.05~2.15, 6.6~7.8×103 g/mol, and 3.6~4.2 cP, respectively, with increasing acid concentration. The re-solubility of raw barley β-glucan was about 50%, but increased to 97% with increasing acid concentration. Acid hydrolysis was shown to be an effective method to produce β-glucan with high ratio of soluble β-glucan content, purity, water solubility, and low viscosity.Hide Abstract
Mohamad, S. A., Awang, M. R., Ibrahim, R., Keong, C. Y., Hamzah, M. Y., Rashid, R. A., Hussein, S., Rahim, K. A., Daud, F., Hamid, A. A. & Yusoff, W. M. W. (2015). Advances in Bioscience and Biotechnology, 6(07), 456.
Four local mushroom species, viz. Auricularis polytricha, Lentinus edodes, Agrocybe sp and Pleurotus flabellatus were grown under submerged culture and screened for endopolysaccharides. The fermentation was done in 250 ml working volume Erlenmeyer flask and the fermentation curves for all species were established. Pleurotus flabellatus has the highest rate of biomass production at the rate of 0.180 g/L/day, at 10 days hence chosen for further investigation. Two additional media, viz. Mushroom Complete Media (MCM) and Yeast Malt (YM) were selected to be compared with potato extract(PE) media used initially. MCM media produced the highest biomass productivity at the rate of 0.311 g/L/day. Pleurotus flabellatus biomass was extracted using modified Mizuno method and the endopolysaccharide obtained was tested for β-glucan. The yield of β-glucan was 7.70 ± 1.11 g/100g. The polysaccharides were purified using column chromatography to yield four fractions. The fourth fraction F4, gave the highest molecular weight at 3.058 × 106 Dalton (11.8%) and 1.282 × 104 Dalton (88.2%). The mushroom, P. flabbelatus was cultured using air-lift bioreactor, and the highest productivity was obtained at air-flowrate 2 L/min, yielding 2.25 g/L/day. The yield of biomass against substrate used (glucose consumption) Yb/s was 0.78 g/g.Hide Abstract
Lam, Y. S. & Okello, E. J. (2015). International Journal of Medicinal Mushrooms, 17(2).
The objective of this study was to quantify a number of bioactive compounds and antioxidant activity of the oyster mushroom, Pleurotus. Ostreatus, and characterize the effects of processing, such as blanching, on these outcomes. Dry matter content was 8%. Lovastatin was not detected in this study. β-glucan content of 23.9% and total polyphenol content of 487.12 mg gallic acid equivalent/100 g of dry matter were obtained in raw P. ostreatus. Antioxidant activities as evaluated by 1,1-diphenyl-2-picrylhydrazyl, Trolox equivalent antioxidant capacity, and ferric reducing antioxidant power assays in raw P. ostreatus were 14.46, 16.51, and 11.21 µmol/g, respectively. Blanching did not significantly affect β-glucan content but caused significant decrease in dry matter content, polyphenol content, and antioxidant activities. Mushroom rolls produced from blanched mushrooms and blanching water contained significantly higher amounts of β-glucan, total polyphenol content, and FRAP antioxidant activity compared to blanched mushrooms. In conclusion, P. ostreatus is a good source for β-glucan, dietary polyphenols, and antioxidants. Although the blanching process could affect these properties, re-addition of the blanching water during the production process of mushroom rolls could potentially recover these properties and is therefore recommended.Hide Abstract
Yoshida, T., Honda, Y., Tujimoto, T., Uyama, H., & Azuma, J. I. (2015). Macromolecular Symposia, 353(1), 205-211.
Enhancement of the extraction rate of β-glucan from corn pericarp (CP) by repeated freeze-thaw treatment of 2% w/w NaOH-6 M urea solution was investigated with emphasis on the association of β-glucan with cellulose in CP. Three freeze-thaw cycles were found to be adequate for extraction of β-glucan at a rate of 97.8%. The increase in extraction rate induced by the freeze-thaw treatment was estimated to be approximately 20%. The natural cellulose I structure of the cellulose in CP was disrupted by the freeze-thaw treatment, suggesting that the increase was due to greater β-glucan solubilization owing to the disruption of its association with cellulose by hydrogen bonds. The applicability of the present technique to other cereals was also demonstrated; extraction rates of 82.8% for oat meal and 92.5% for barley flour were achieved.Hide Abstract
Jaehrig, S. C., Rohn, S., Kroh, L. W., Fleischer, L. G. & Kurz, T. (2007). Journal of Agricultural and Food Chemistry, 55(12), 4710-4716.
(1→3),(1→6)-β-D-Glucan, a cell wall polysaccharide in many microorganisms, fungi and algae, is a well-known biological response modifier. Recently, it was found that (1→3)-β-D-glucan from Saccharomyces cerevisiae also exhibits antioxidative capabilities. In this study the antioxidative activity of the cell wall fractions of brewer's yeast was investigated. Particular emphasis was put on the question to which extent glucan is responsible for the antioxidative activity of the cell walls and how the other cell wall components might contribute. For the experiments yeast cell walls from brewery fermentations were used. Glucan was isolated by a three-step extraction procedure including a combination of hot water and enzymatic treatment. The level of (1→3),(1→6)-β-D-glucan in the cell walls was analyzed enzymatically. The antioxidant activity was determined by electron paramagnetic resonance spectrometry and Trolox equivalent antioxidant capacity assay. The results show that the antioxidative activity of yeast cell wall proteins exceeds that of β-glucan greatly. Especially aromatic side chains and free thiols from denatured proteins seem to work as antioxidants.Hide Abstract