Andriy Synytsya’s research while affiliated with University of Chemistry and Technology and other places

Sourdough fermentation of bran can overcome the technological problems encountered in bread making but favors the activity of endogenous β-glucanase leading to a degradation of β-glucans. This study investigated the effects of high-intensity ultrasound (US) pretreatment of oat bran (OB) and barley bran (BB) on its β-glucans content, properties, and preservation in processing, as well as on the acidification kinetics of bran sourdough fermentation and on its application in flatbread. To reduce β-glucanase activity, OB and BB (15% water suspensions) were US-pretreated prior to sourdough fermentation. The acidification kinetics, the microbial viable cell count, and the total titratable acidity (TTA) of the sourdough were determined. The total β-glucans content of bran, sourdough, and bread, as well as water solubility and the molecular weight (Mw) of untreated and US-pretreated bran, were investigated. The physical properties of control wheat and composite flatbreads were compared. The US-pretreatment increased the acidification rate (30%) and TTA (51%) of OB sourdough, however, decreased the acidification rate of BB (18%). After the US-pretreatment of OB and BB, the total (11.5–12.3%) and water-soluble β-glucans (31–40%) increased while their Mw decreased (7–21.7%). In sourdough and flatbread prepared with US-pretreated OB/BB, 93–95% and 90–98% of β-glucans were retained, respectively, compared to 64–72% and 82–92% in control samples. The US-pretreatment and/or sourdough fermentation of OB and BB resulted in flatbreads of higher specific volume (8–22%) and cohesiveness (11–20%) while reduced hardness (40–55%) and chewiness (51–73%) compared to their control bread.

Two strains of Tunisian oyster mushrooms, identified as Pleurotus eryngii var. elaeoselini and var. ferulae, were investigated as promising for agricultural biodiversity based on the biopolymer composition of the mycelia, liquid cultural filtrate, and fruiting bodies. Results reveal the differences for these varieties in protein and d-glucan contents. The first strain exhibited high level of proteins in its fruiting bodies (17.7% w/w), while the second strain showed a high amount of fruiting body d-glucans (28.08% dry matter). Water-soluble polysaccharide fractions were isolated from the cultural filtrate of mycelia and fruiting bodies. Monosaccharide composition and linkages, FTIR, and NMR spectra of all these fractions confirmed the prevalence of α-d-mannan or mannogalactan over d-glucans. The cultural filtrate of Pleurotus eryngii var. elaeoselini was rich in α-d-mannan, while the mannogalactan was observed only in fruiting bodies of this strain. By contrast, Pleurotus eryngii var. ferulae provided a mixture of these two polysaccharides at different proportions both in cultural filtrate and fruiting bodies. The markedly diverse distribution of potential nutraceutical proteins and polysaccharides makes these two Pleurotus eryngii strains promising for increasing agricultural biodiversity in Tunisia and, generally, the North African region.

Sourdough fermentation of bran can overcome the technological problems encountered in bread making but favors the activity of endogenous β-glucanase leading to a degradation of β-glucans. This study investigated the effects of high-intensity ultrasound (US) pretreatment of oat (OB) and barley (BB) bran on its β-glucans content, properties, and preservation in processing, as well as the on the acidification kinetics of bran sourdough fermentation and on its application in flatbread. To reduce β-glucanase activity, OB and BB (15 % water suspensions) were US-pretreated prior to sourdough fermentation. The acidification kinetics, the microbial viable cell count, and the total titratable acidity (TTA) of the sourdough were determined. The total β-glucans content of bran, sourdough, and bread, as well as water solubility and the molecular weight (Mw) of control and US-pretreated bran were investigated. The physical properties of control wheat and composite flatbreads were compared. The US-pretreatment increased the acidification rate (30%) and TTA (51%) of OB sourdough, however decreased the acidification rate of BB (18%). After the US-pretreatment of OB and BB, the total (11.5-12.3 %) and water-soluble β-glucans (31-40 %) increased while their Mw decreased (7-21.7 %). In sourdough and flatbread prepared with US-pretreated OB/BB, 93-95 % and 90-98 % of β-glucans were retained, respectively, compared to 64-72 % and 82-92 % in control samples. The US-pretreatment and/or sourdough fermentation of OB and BB resulted in flatbreads of higher specific volume (8-22 %) and cohesiveness (11-20%) while reduced hardness (40-55 %) and chewiness (51-73 %) compared to their control bread.

This study examined the effects of pulsed electric field (PEF) treatment on enzymes, non-starch polysaccharides, and bread-making potential of oat and barley flour. Enzyme activity, microstructure, β-glucan extractability, molecular weight (Mw) and structure of non-starch polysaccharides, dough rheology, and flat bread properties were determined. An exponential decay model explained better the residual activity of oat β-glucanase across electric field intensity than barley β-glucanase. PEF treatment of flour at 12 kV/cm for 162 ms significantly reduced β-glucanase activity (40.2–76.5%) while increasing the concentration of total β-glucans (33.5%) and water-extractable arabinoxylans (36–41%). Mw of linear β-d-glucans decreased (9%) while Mw of branched arabinoxylans increased (6–33%). Scanning electron microscopy showed changes in microstructure of barley proteins. Blending wheat flour (70%) with oat or barley flour (30% weight) after PEF treatment enhanced gluten aggregation energy (29–19%) and breakdown viscosity (18–43%) of dough, as well as increased β-glucan content (21–32%) but reduced specific volume (11–24%). The findings of this study provide a comprehensive insight into the PEF’s potential for retarding enzymatic reactions and preserving integrity of cereal non-starch polysaccharides.

This study examined the effects of pulsed electric field (PEF) treatment on enzymes, non-starch polysaccharides, and bread making potential of oat and barley flour. Enzymes activity, microstructure, β-glucans extractability, molecular weight (Mw) and structure of non-starch polysaccharides, dough rheology and flat bread properties were determined. An exponential decay model explained better the residual activity of oat β-glucanase across electric field intensity than barley β-glucanase. PEF treatment of flour at 12 kV/cm for 162 ms significantly reduced β-glucanase activity (40.2–76.5%) while increased the concentration of total β-glucans (33.5%) and water-extractable arabinoxylans (36–41%). Mw of linear β-d-glucans decreased (9%) while Mw of branched arabinoxylans increased (6–33%). Scanning electron microscopy showed changes in microstructure of barley proteins. Blending wheat flour (70%) with oat or barley flour (30% weight) after PEF treatment enhanced gluten aggregation energy (29–19%) and breakdown viscosity (18–43%) of dough, as well as increased β-glucans content (21–32%) but reduced specific volume (11–24%). The findings of this study provide a comprehensive insight into the PEF's potential for retarding enzymatic reactions and preserving integrity of cereal non-starch polysaccharides.

Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy was proposed for rapid, versatile, and non-invasive screening of Ganoderma basidiocarps to assess their potential for specific applications. Fifteen species and strains of this fungus were selected for analysis, and fine sections at different parts of young and mature basidiocarps were obtained. The spectra of fungal samples showed significant differences interpreted in terms of biochemical composition using characteristic bands of proteins, polysaccharides, lipids, and triterpenoids. Obviously, for the transverse sections in trama, especially in the basal part, the most intense bands at 950–1200 cm−1 corresponded to polysaccharide vibrations, while for the superficial sections, the bands of carbonyl and aliphatic groups of triterpenoids at 1310–1470, 1550–1740, and 2850–2980 cm−1 predominated. The pilei, especially hymenium tubes, apparently contained more proteins than the bases and stipes, as evidenced by the intense bands of amide vibrations at 1648 and 1545–1550 cm−1. The specificity of the Ganoderma basidiocarp is a densely pigmented surface layer rich in triterpenoids, as proved by ATR-FTIR spectroscopy. The spectral differences corresponding to the specificity of the triterpenoid composition may indicate the prospects of individual strains and species of this genus for cultivation and further use in food, cosmetics, or medicine.

The ear- to shell-shaped fruiting bodies of the genus Auricularia are widely used as food and in traditional medicinal remedies. This study was primarily focused on the composition, properties and potential use of the gel-forming extract from Auricularia heimuer. The dried extract contained 50% soluble homo- and heteropolysaccharides, which were mainly composed of mannose and glucose, acetyl residues, glucuronic acid and a small amount of xylose, galactose, glucosamine, fucose, arabinose and rhamnose. The minerals observed in the extract included approximately 70% potassium followed by calcium. Among the fatty and amino acids, 60% unsaturated fatty acids and 35% essential amino acids could be calculated. At both acidic (pH 4) and alkaline (pH 10) conditions, the thickness of the 5 mg/mL extract did not change in a temperature range from −24 °C to room temperature, but decreased statistically significantly after storage at elevated temperature. At neutral pH, the studied extract demonstrated good thermal and storage stability, as well as a moisture retention capacity comparable to the high molecular weight sodium hyaluronate, a well-known moisturizer. Hydrocolloids that can be sustainably produced from Auricularia fruiting bodies offer great application potential in the food and cosmetic industries.

For centuries human civilization has cultivated oats, and now they are consumed in various forms of food, from instant breakfasts to beverages. They are a nutrient-rich food containing linear mixed-linkage (1 → 3) (1 → 4)-β-d-glucans, which are relatively well soluble in water and responsible for various biological effects: the regulation of the blood cholesterol level, as well as being anti-inflammatory, prebiotic, antioxidant, and tumor-preventing. Numerous studies, especially in the last two decades, highlight the differences in the biological properties of the oat β-d-glucan fractions of low, medium, and high molecular weight. These fractions differ in their features due to variations in bioavailability related to the rheological properties of these polysaccharides, and their association with food matrices, purity, and mode of preparation or modification. There is strong evidence that, under different conditions, the molecular weight may determine the potency of oat-extracted β-d-glucans. In this review, we intend to give a concise overview of the properties and studies of the biological activities of oat β-d-glucan preparations depending on their molecular weight and how they represent a prospective ingredient of functional food with the potential to prevent or modulate various pathological conditions.

Vibrational spectroscopic methods are widely used in the molecular diagnostics of carcinogenesis. Collagen, a component of connective tissue, plays a special role as a biochemical marker of pathological changes in tissues. The vibrational bands of collagens are very promising to distinguish between normal colon tissue, benign and malignant colon polyps. Differences in these bands indicate changes in the amount, structure, conformation and the ratio between the individual structural forms (subtypes) of this protein. The screening of specific collagen markers of colorectal carcinogenesis was carried out based on the FTIR and Raman (λex 785 nm) spectra of colon tissue samples and purified human collagens. It was found that individual types of human collagens showed significant differences in their vibrational spectra, and specific spectral markers were found for them. These collagen bands were assigned to specific vibrations in the polypeptide backbone, amino acid side chains and carbohydrate moieties. The corresponding spectral regions for colon tissues and colon polyps were investigated for the contribution of collagen vibrations. Mentioned spectral differences in collagen spectroscopic markers could be of interest for early ex vivo diagnosis of colorectal carcinoma if combine vibrational spectroscopy and colonoscopy.