In vitro fermentation profile of soluble dietary fibers obtained by different enzymatic extractions from barley bran Publication date: Available online 14 November 2019 Source: Bioactive Carbohydrates and Dietary Fibre Author(s): Reza Karimi, Mohammad Hossein Azizi, Mohammad Ali Sahari, Ahmad Enosh Kazem Abstract The purpose of this study was to compare the fermentative properties of enzymatically extracted barley bran dietary fibers using a batch in vitro fecal fermentation method. Fibers with different β-glucan contents and molecular weights (Mw) were utilized. Fecal fermentation profiles were evaluated based on pH values, produced gas, total short chain fatty acid (SCFA), ratio and amounts of SCFA including acetate, propionate and butyrate during 6, 12 and 24 h of fermentation. The samples were compared with fructooligosaccharide (FOS) and blank for mentioned properties. Fiber extracted by α-amylase which had the lowest β-glucan purity (∼55%) and the highest Mw (163 kDa) indicated the lowest gas production, the lowest amount of total SCFA production and the highest pH after 24 h of fermentation. On the other hand, Fiber extracted by α-amylase, protease and glucoamylase which had moderate β-glucan purity (∼68%) and relatively low Mw (26 kDa), showed the greatest gas production, the highest total SCFA amount, the highest amounts of acetate, propionate and butyrate and the lowest pH, at the end of the fermentation period. This study helps to provide a new approach to obtain details regarding the fermentability of the enzymatically extracted dietary fibers. Graphical abstract

Biotechnological potential of exopolysaccharide as a bioemulsifier produced by Rhizobium radiobacter CAS isolated from curd Publication date: October 2019 Source: Bioactive Carbohydrates and Dietary Fibre, Volume 20 Author(s): Digambar Kavitake, Farhat Zakirhusain Marchawala, Cedric Delattre, Prathapkumar Halady Shetty, Hilor Pathak, Prasad Andhare Abstract Succinoglycan exopolysaccharide (EPS) from Rhizobium radiobacter CAS and its rheological behavior has been studied earlier. In present investigation the emulsifying potential of CAS EPS has been determined. CAS EPS concentration was optimized with hydrocarbons soybean oil and n-Hexane, whereas effect of pH (3.0–11.0), salinity, monovalent ions, divalent ion, (NaCl, KCl and MgCl2), freezing/thawing, temperature heating, emulsion stability and rheology on emulsifying activity (EA) was inspected using n-Hexane, paraffin oil, groundnut oil and soybean oil. CAS biopolymer represented superior emulsion stabilization ability (100%) under stress conditions and was highly tolerant to extreme pH, inorganic salts concentrations. Thermal stability of emulsions has found 100% at −20 °C–40 °C, whereas, at temperature 50 °C–120 °C high emulsion index (82.4–94.1% respectively) were recorded. Wetting filter paper test verified oil-in-water (o/w) type emulsion whereas rheological property showed pseudoplastic nature of emulsions. During stability of emulsions up to 30 days, some reduction of emulsification activity was observed for paraffin oil, however CAS hydrocolloid formed 100% emulsion index for n-Hexane, groundnut and soybean oils. These emulsifying and better hydrophilic physical properties make CAS hydrocolloid a prospective alternative to commercial biopolymers and chemical surfactants. Graphical abstract

Isolation of crude fucoidan from Sargassum wightii using conventional and ultra-sonication extraction methods Publication date: October 2019 Source: Bioactive Carbohydrates and Dietary Fibre, Volume 20 Author(s): Mandakini Devi Hanjabam, Anuj Kumar, C.S. Tejpal, Elavarasan Krishnamoorthy, Pankaj Kishore, K. Ashok Kumar Abstract Fucoidan, a fucose rich sulphated polysaccharide, generally found in cell wall matrix of brown seaweeds possess diverse physiological properties. Crude fucoidan was extracted from Sargassum wightii, a brown seaweed common along the Indian coastline. A comparison was made between hot water extraction (HWE) and ultra-sonication extraction (UAE) methods. The UAE method gave higher yield (14.61 g/100 g) than HWE method (10.59 g/100 g). The UAE fucoidan had lighter colour than HWE, as indicated by Hunter colour values. The water activity values for fucoidans obtained were 0.14 for HWE and 0.19 for UAE. The sulphate content was similar in both fucoidans (̴17%). However, HWE fucoidan had higher content of fucose. The Fourier transform infrared spectroscopy spectra confirmed the presence of sulphate groups in both the fucoidans. The absorption bands at 1245.37 cm−1 and 1294.99 cm−1 in the HWE and UAE fucoidan respectively, indicated the S–O stretching due to sulphate groups in the fucose monomer. The thermal transition temperature as obtained by differential scanning calorimetry for HWE (127.3 °C) was lower than UAE fucoidan (131.8 °C). HWE fucoidan had higher DPPH radical scavenging and reducing power than UAE fucoidan. On the other hand, UAE fucoidan had higher metal chelating activity. The present study demonstrated that ultra-sonication can be an effective alternative for the extraction of sulphated polysaccharide from seaweed, in term of higher yield. The health benefits of Sargassum wightii and fucoidan obtained from it, could be explored by incorporation in different food systems. Graphical abstract

Prebiotic potential of natural gums and starch for bifidobacteria of variable origins Publication date: October 2019 Source: Bioactive Carbohydrates and Dietary Fibre, Volume 20 Author(s): Nikol Modrackova, Marie Makovska, Chahrazed Mekadim, Eva Vlkova, Vaclav Tejnecky, Petra Bolechova, Vera Bunesova Abstract Complex polysaccharide polymers of natural origin are widely used as natural food thickeners. They are useful for their technological properties, and at the same time they are biodegradable and safe for consumers. In addition, natural food thickeners, such as natural gums (NGs) and starch, may also represent suitable potentially prebiotic substrates for probiotic genera such as the genus Bifidobacterium. Therefore, 204 bifidobacterial strains of 60 species and subspecies were tested for their ability to utilize 6 NGs (locust bean, guar, tragacanth, arabic, xanthan, and karaya gums) and starch. Here we observed that the ability to utilize these substrates as a single carbon source is species and strain specific trait reflecting the host origin and diet. The utilization was evaluated based on the pH change, metabolite formation, and detection of viable bifidobacterial counts. In conclusion, 114 strains of human and animal origin (37 bifidobacterial species and subspecies) were able to utilize starch. Compared to that, mostly bifidobacteria of the animal origin were able to utilize a wider range of available natural substrates compared to the human bifidobacteria. In total, 29 strains were able to use NGs (10 species and subspecies). Most often used locust bean, guar, tragacanth, and arabic gums represent possible prebiotic sources for bifidobacteria in animal nutrition, ideally in synbiotic applications. Natural food thickeners were found to be useful potential prebiotics. However, a suitable combination with probiotic Bifidobacterium strains is required. Graphical abstract

Ultrasound assisted extraction of the polysaccharide from Tuber aestivum and its in vitro anti-hyperglycemic activity Publication date: October 2019 Source: Bioactive Carbohydrates and Dietary Fibre, Volume 20 Author(s): Devshri S. Mudliyar, Janne H. Wallenius, Dattatray K. Bedade, Rekha S. Singhal, Nuri Madi, Salem S. Shamekh Abstract Tuber aestivum is one of the most popular and delicious truffles in the world economic market and is reported to possess a wide range of biological activities. The total carbohydrate of this truffle constitutes about 5.65% w/w dry weight basis (dwb). The present work compares the yield of the polysaccharide obtained by conventional hot water extraction followed by alcohol precipitation, and ultrasound assisted extraction using low power 150 W probe sonifier. The parameters of ultrasound assisted extraction (amplitude, extraction time, pH, and liquid-solid ratio) from the fruiting body of T. aestivum were optimized using Taguchi orthogonal array and central composite design. The optimal parameters of extraction were a liquid-solid ratio of 75:1 for 15 min at pH 6.5 at an amplitude of 25%, which yielded 68.91 ± 1.54% w/w dwb polysaccharide. The FTIR and SEM characteristics of the polysaccharides obtained by ultrasonic extraction and conventional hot water extraction were similar. Further, the polysaccharides extracted from T. aestivum demonstrated a significant in vitro anti-hyperglycemic activity.

Biosynthesis of methyl glucoside and its antibacterial activity against Staphylococcus aureus and Escherichia coli Publication date: October 2019 Source: Bioactive Carbohydrates and Dietary Fibre, Volume 20 Author(s): Jarunee Kaulpiboon, Prakarn Rudeekulthamrong Abstract In this study, the methyl glucosides (MGn) was synthesized using β-cyclodextrin (β-CD) and methanol through the coupling reaction of recombinant cyclodextrin glycosyltransferase (CGTase) from Bacillus circulans A11. The optimal condition for the synthesis of MGn consisted of an incubation of 1.5% (w/v) β-CD and 500 U/mL of CGTase in a water/methanol solution containing 30% (v/v) methanol at pH 6.0, 50 °C for 120 h. Upon analysis by TLC, at least three MG products were observed. The molecular weight of the main transferred product was 217.08 Da; this value was in accordance with methyl monoglucoside (MG1). MG1 was produced and prepared on a large scale and subsequently purified by preparative TLC. The combined 1H- and 13C-NMR analysis confirmed that the structure of MG1 was methyl-α-d-glucopyranoside. In addition, MG1 showed emulsification activity and stability in its formation in water and n-hexadecane. The antibacterial activity of MG1 was also determined by agar disc diffusion method. The results found that the MG1 (1, 5 and 10 mg/disc) showed antibacterial activity against E. coli ATCC 25922 only, with inhibition zones of 28, 38 and 40 mm, respectively. The MIC values (mg/mL) of MG1 against S. aureus ATCC 25923 and E. coli ATCC 25922 were found to be 20.00 and 0.63, while MBC values (mg/mL) were 40.00 and 0.63, respectively. Graphical abstract

Investigating potential wound healing properties of polysaccharides extracted from Grewia mollis Juss. and Hoheria populnea A. Cunn. (Malvaceae) Publication date: October 2019 Source: Bioactive Carbohydrates and Dietary Fibre, Volume 20 Author(s): N. Pearman, S.R. Moxon, S.M. Carnachan, M.E. Cooke, E.I. Nep, I.M. Sims, G.A. Morris, A.M. Smith Abstract The Malvaceae family is a group of flowering plants that include approximately 244 genera, and 4225 species. Grewia mollis, and Hoheria populnea (lacebark), are examples of the Malvaceae family that are used in traditional medicine. For this study polysaccharide samples were extracted from the inner bark of Grewia mollis (unmodified (GG) and destarched grewia gum (GGDS)) and from the leaves of Hoheria populnea (lacebark polysaccharide (LB)). Wound healing properties of grewia gum and lacebark polysaccharides were investigated using 3T3 fibroblast cells cultured in supplemented DMEM. Deposition of collagen using van Gieson's stain, expression of the COL1A1 gene which encodes type I collagen using quantitative PCR, and chemotaxis using a scratch plate assay were analysed following treatment of cells with the test polysaccharides. Quantitative PCR results indicated that all three polysaccharides increased the levels of COL1A1 mRNA, with GG showing the greatest fold change. Histological staining also indicated that the fibroblasts treated with GG deposited more collagen than control cells. Additionally, scratch assay data indicated that simulated cell ‘wounds’ treated with each polysaccharide showed increased wound closure rate over a 36 h period post treatment, with GG exhibiting the greatest effect on wound closure. Analysis of the Malvaceae derived polysaccharides indicates that they could have a positive effect on mechanisms that are integral to wound healing, potentially providing greater scientific understanding behind their use in traditional medicine. Graphical abstract

In vitro determination of prebiotic potential of aqueous extract of horse chestnut by-product Publication date: July 2019 Source: Bioactive Carbohydrates and Dietary Fibre, Volume 19 Author(s): Joanna Przyborska, Michael C. Hall, Mary Concannon

Hypocholesterolemic potential and bioactivity spectrum of an exopolysaccharide from a probiotic isolate Lactobacillus paracasei M7 Publication date: July 2019 Source: Bioactive Carbohydrates and Dietary Fibre, Volume 19 Author(s): Bilqeesa Bhat, Bijender Kumar Bajaj Abstract Ever-rising prevalence of cardiovascular diseases (CVDs) has induced enormous research impetus for reducing cardiovascular risk factors through innovative approaches. One of the major causes of CVDs is elevated level of serum cholesterol which though could be managed by drugs. But considering serious side effects of most of the available cholesterol lowering drugs, development of nonpharmacological cholesterol lowering approaches have gained momentum. Probiotics and/or derived metabolites (such as exopolysaccharides) are reported for their ability to reduce serum cholesterol level. Exopolysaccharides (EPS) due to their wide bioactivity spectrum (hypocholesterolemic, antioxidant, immunostimulatory, and others), and usage as food-additive (thickener, stabilizer, gelling agent, and others) may have application potential for pharmaceutical/food industries. Current study reports the EPS producing potential of a probiotic Lactobacillus paracasei M7, an isolate from human breast milk. The EPS of L. paracasei M7 exhibited excellent functional characteristics like hypocholesterolemic (70.78%), antioxidant activity (DPPH radical scavenging activity 78.09%; hydroxyl radical scavenging activity 74.64%), and antibiofilm potential (59–64%) against several human pathogens. The EPS formed highly stable emulsion with vegetable oils (olive, peanut, coconut, and soybean oil). Although hypocholesterolemic activity of probiotics is known but scarce reports are available on cholesterol lowering potential of EPS. Physicochemical analysis of L. paracasei M7 EPS by FTIR, XRD, HPLC, SEM, and TEM, and thermal analysis (TGA/DSC) elucidated the structure-function relationship, and provided insights into the functional mechanisms of EPS. Versatile bioactivity potential of L. paracasei M7 EPS reflects its application prospective in food and pharmaceutical industry, especially for management of CVDs. Graphical abstract

β-Glucan, a dietary fiber in effective prevention of lifestyle diseases – An insight Publication date: July 2019 Source: Bioactive Carbohydrates and Dietary Fibre, Volume 19 Author(s): Gunjan Maheshwari, Sumathi Sowrirajan, Baby Joseph Abstract β-Glucan (β-G), a dietary fiber and a biologically active natural polysaccharide, is helpful in the prevention and control of obesity, cardiovascular diseases, diabetics and cancer. Witnessing an increasing trend in mortality due to these diseases, especially in low- and middle-income countries can partly be attributed to dietary habits. This review deliberately discusses the global scenario on the life style diseases (LSDs), its relation to food habits on a regional basis and their effective prevention with β-glucan. Lowering the LDL cholesterol, the glycemic index and blood sugar, along with the antioxidant, anticancer and free radical scavenging property, β-glucan is efficient in trapping the reactive oxygen. But its easy availability as an affordable dietary supplement, is yet to be attended. Graphical abstract