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The use of β-glucosidase positive strains, as tailored-starter cultures for table olives fermentation, is a useful biotechnological tool applied to accelerate the debittering process. Nowadays, strains belonging to Lactiplantibacillus plantarum species are selected for their high versatility and tolerance to stress conditions. The present study investigated the effect of different stress factors (pH, temperature and NaCl) on growth and on oleuropein-degrading abilities of selected L. plantarum strains. In addition, the presence of the beta-glucosidase gene was investigated by applying a PCR based approach. Results revealed that, overall, the performances of the tested strains appeared to be robust toward the different stressors. However, the temperature of 16 °C significantly affected the growth performance of the strains both singularly and in combination with other stressing factors since it prolongs the latency phase and reduces the maximum growth rate of strains. Similarly, the oleuropein degradation was mainly affected by the low temperature, especially in presence of low salt content. Despite all strains displayed the ability to reduce the oleuropein content, the beta-glucosidase gene was detected in five out of the nine selected strains, demonstrating that the ability to hydrolyze the oleuropein is not closely related to the presence of beta-glucosidase. Data of the present study suggest that is extremely important to test the technological performances of strains at process conditions in order to achieve a good selection of tailored starter cultures for table olives.

The non-lysosomal glucosylceramidase GBA2 catalyzes the hydrolysis of glucosylceramide to glucose and ceramide. Loss of GBA2 function results in accumulation of glucosylceramide. Mutations in the human GBA2 gene have been associated with hereditary spastic paraplegia (HSP) and autosomal-recessive cerebellar ataxia (ARCA). Patients suffering from these disorders exhibit impaired locomotion and neurological abnormalities. GBA2 mutations found in these patients have been proposed to impair GBA2 function. However, the molecular mechanism underlying the occurrence of mutations in the GBA2 gene and the development of locomotor dysfunction is not well-understood. In this review, we aim to summarize recent findings regarding mutations in the GBA2 gene and their impact on GBA2 function in health and disease.

The major cause of hyperglycemia can generally be attributed to β-glucosidase as per its involvement in non-alcoholic fatty liver disease. This clinical condition leads to liver carcinoma (HepG2 cancer). The phthalimides and phthalamic acid classes possess inhibitory potential against glucosidase, forming the basis for designing new phthalimide and phthalamic acid analogs to test their ability as potent inhibitors of β-glucosidase. The study also covers in silico (molecular docking and MD simulations) and in vitro (β-glucosidase and HepG2 cancer cell line assays) analyses. The phthalimide and phthalamic acid derivatives were synthesized, followed by spectroscopic characterization. The mechanistic complexities associated with β-glucosidase inhibition were identified via the docking of the synthesized compounds inside the active site of the protein, and the results were analyzed in terms of the best binding energy and appropriate docking pose. The top-ranked compounds were subjected to extensive MD simulation studies to understand the mode of interaction of the synthesized compounds and binding energies, as well as the contribution of individual residues towards binding affinities. Lower RMSD/RMSF values were observed for 2c and 3c , respectively, in the active site, confirming more stabilized, ligand-bound complexes when compared to the free state. An anisotropic network model was used to unravel the role of loop fluctuation in the context of ligand binding and the dynamics that are distinct to the bound and free states, supported by a 3D surface plot. An in vitro study revealed that 1c (IC 50 = 1.26 µM) is far better than standard acarbose (2.15 µM), confirming the potential of this compound against the target protein. Given the appreciable potential of the candidate compounds against β-glucosidase, the synthesized compounds were further tested for their cytotoxic activity against hepatic carcinoma on HepG2 cancer cell lines. The cytotoxicity profile of the synthesized compounds was performed against HepG2 cancer cell lines. The resultant IC 50 value (0.048 µM) for 3c is better than the standard (thalidomide: IC 50 0.053 µM). The results promise the hypothesis that the synthesized compounds might become potential drug candidates, given the fact that the β-glucosidase inhibition of 1c is 40% better than the standard, whereas compound 3c holds more anti-tumor activity (greater than 9%) against the HepG2 cell line than the known drug.

Highlights • Deep eutectic solvents (DESs) was developed in β-glucosidase biocatalysis. • A novel DES (ChCl:PG, 1:2) was believed to improve the enzyme activity and stability. • The effects of DESs on enzyme activity in two systems were studied. • Kinetic analysis further explored the mechanisms of different solvent models. Abstract This work reports a group of new “green” reaction medium-deep eutectic solvents (DESs) as modes in the hydrolysis of p-nitrophenyl-β-glucopyranoside using β-glucosidase as a biocatalyst. The tested DESs consisted of mixtures of a choline salt and three different types of hydrogen bond donors: amides, alcohols and sugars. These eutectic solvents are easily accessible, biodegradable, and inexpensive alternatives to conventional ionic liquids. Herein, the DESs compared with 1-ethyl-3-methylimidazolium tetrafluoroborate and methanol were studied by evaluating enzyme activity and enzyme stability; and a novel DES, choline chloride: propylene glycol (ChCl:PG, 1:2) was believed to be the most appropriate solvent to improve the bioconversion efficiency. When ChCl:PG (40%, v/v) as a co-solvent, β-glucosidase activity was increased to 225% compared to buffer system. Moreover, the enzyme thermal stability in ChCl:PG retained 62% of their initial activity in the fifth day, which was superior to phosphate buffer solution and methanol. On the contrary, the enzyme was mostly deactivated in pure DESs, while adding a certain amount of water was able to eliminate the adverse effects. It can be concluded that the water content in the solvent system will significantly affect the activity of solvent on enzymes. The Kinetic analysis further described that an increase in enzyme affinity toward the substrate in the DESs system was responsible for the enhancement of enzymatic efficiency. [ABSTRACT FROM AUTHOR]

β-Glucosidase plays an important role in the degradation of cellulose. In this study, a novel β-glucosidase ccbgl1b gene for a glycosyl hydrolase (GH) family 1 enzyme was cloned from the genome of Cellulosimicrobium cellulans and expressed in Escherichia coli BL21 cells. The sequence contained an open reading frame of 1494 bp, encoded a polypeptide of 497 amino acid residues. The recombinant protein CcBgl1B was purified by Ni sepharose fastflow affinity chromatography and had a molecular weight of 57 kDa, as judged by SDS-PAGE. The optimum β-glucosidase activity was observed at 55 °C and pH 6.0. Recombinant CcBgl1B was found to be most active against aryl-glycosides p-nitrophenyl-β-D-glucopyranoside (pNPβGlc), followed by p-nitrophenyl-β-D-galactopyranoside (pNPβGal). Using disaccharides as substrates, the enzyme efficiently cleaved β-linked glucosyl-disaccharides, including sophorose (β-1,2-), laminaribiose (β-1,3-) and cellobiose (β-1,4-). In addition, a range of cello-oligosaccharides including cellotriose, cellotetraose and cellopentaose were hydrolysed by CcBgl1B to produce glucose. The interaction mode between the enzyme and the substrates driving the reaction was modelled using a molecular docking approach. Understanding how the GH1 enzyme CcBgl1B from C. cellulans works, particularly its activity against cello-oligosaccharides, would be potentially useful for biotechnological applications of cellulose degradation. [ABSTRACT FROM AUTHOR]

Bacillus sp. SJ-10 (KCCM 90078, JCM 15709) is a halotolerant bacterium isolated from a traditional Korean food, i.e., salt-fermented fish (jeotgal). The bacterium can survive and engage in metabolism at high salt concentrations. Here, we reported complete genome sequence of Bacillus sp. SJ-10, which has a single circular chromosome of 4,041,649 base pairs with a guanine-cytosine content of 46.39%. Bacillus sp. SJ-10 encodes a subunit of poly-γ-glutamic acid (γ-PGA) with a molecular weight of approximately 400 kDa, which contains four γ-PGA synthases (pgsB, pgsC, pgsAA and pgsE) and one γ-PGA-releasing gene (pgsS). This bacterium also able to produce salt-stable enzymes such as protease, β-glucosidase, and β-1,3-1,4-glucanase. This affords significant insights into strategies employed by halotolerant bacteria to survive at high salt concentrations. The sequence contains information on secondary metabolites biosynthetic gene cluster, and most importantly enzymes produced by the bacterium may be valuable with respect to food, beverage, detergent, animal feed, and certain commercial contexts. [ABSTRACT FROM AUTHOR]

The industrial application of Trichoderma reesei has been greatly limited by insufficient β-glucosidase activity in its cellulase system. In this study, a novel β-glucosidase expression cassette was constructed and integrated at the target site in T. reesei ZU-02, which achieved the overexpression of β-glucosidase gene and in situ disruption of the cellulase transcriptional repressor ACE1. The resulting transformants showed significant increase in both β-glucosidase activity (BGA) and filter paper activity (FPA). The BGA and FPA increased to 25.13 IU/mL and 20.06 FPU/mL, respectively, 167- and 2.45-fold higher than that of the host strain. Meanwhile, the obtained cellulase system exhibited improved ratio of BGA to FPA, leading to better synergistic effect between cellulase components. Furthermore, submerged fermentation of the transformant was established in 50 m3 fermenter yielding 112.2 IU/mL β-glucosidase and 89.76 FPU/mL total cellulase. The newly constructed T. reesei transformant achieved improved hydrolysis yield (90.6%) with reduced enzyme loading (15 FPU/g substrate). [ABSTRACT FROM AUTHOR]

The final step in lignocellulose enzymatic saccharification is the cellobiose conversion to glucose by (β-glucosidases (BG). In this work, a valid kinetic model to describe cellobiose degradation for an industrial mixture of BG enzymes present in Aspergillus fumigatus is selected. Firstly, the enzyme mixture was characterised in terms of protein content and enzymatic activity on p-NPG …, determining the molecular weight of the only BG activity band observed in zymograms by SDS-PAGE and MALDI-TOF: 94kDa. Subsequently, to select the correct kinetic model for the enzymatic hydrolysis of cellobiose, a combined strategy was performed: Firstly, non-linear regressions were applied to initial hydrolysis rate data for different enzyme concentrations and initial substrate and product concentrations, observing inhibition by cellobiose and glucose. Secondly, the optimal kinetic model was discriminated by a coupled non-linear regression-DOE numerical integration approach, by fitting several possible kinetic models involving different product inhibition mechanisms to progress curve data from runs at various initial substrate concentrations and temperatures. The best kinetic model involves non-competitive substrate inhibition and product competitive inhibition with two binding sites for glucose. [ABSTRACT FROM AUTHOR]

Low-cost saccharification is one of the key bottlenecks hampering the further application of lignocellulosic biomass. Clostridium thermocellum is a naturally ideal cellulose degrading bacterium armed with cellulosomes, which are multienzyme complexes that are capable of efficiently degrading cellulose. However, under controlled condition, the inhibition effect of hydrolysate cellobiose severely restricts the hydrolytic ability of cellulosomes. Although the addition of beta-glucosidase (Bgl) could effectively relieve this inhibition, the spatial proximity effect of Bgl and cellulosomes on cellulose degradation is still unclear. To address this issue, free Bgl from Caldicellulosiruptor sp. F32 ( Ca BglA), carbohydrate-binding module (CBM) fused Ca BglA ( Ca BglA-CBM) and cellulosomal type II cohesin module (CohII) fused to Ca BglA ( Ca BglA-CohII) were successfully constructed, and their enzymatic activities, binding abilities and saccharification efficiencies were systematically investigated in vitro and in vivo . In vivo , with the adjacency of Ca BglA to cellulosomes, the saccharification efficiency of microcrystalline cellulose increased from 40% to 50%. For the pretreated wheat straw, the degradation rate of the combination of cells and the Ca BglA-CohII or the Ca BglA-CBM was as efficient as that of the free Ca BglA (approximately 60%). This study demonstrated that the proximity of Ca BglA to cellulosomes had a positive effect on microcrystalline cellulose but not on pretreated wheat straw, which may result from the nonproductive adsorption of lignin and the decreased thermostability of Ca BglA-CBM and Ca BglA-CohII compared to that of Ca BglA. The above results will contribute to the design of cost-effective Bgls for industrial cellulose degradation. [ABSTRACT FROM AUTHOR]

Cytophaga hutchinsonii, belonging to Bacteroidetes, is speculated to use a novel cell-contact mode to digest cellulose. In this study, we identified a histone-like protein HU, CHU_2750, in C. hutchinsonii, whose transcription could be induced by crystalline but not amorphous cellulose. We constructed a CHU_2750-deleted mutant and expressed CHU_2750 in Escherichia coli to study the gene’s functions. Our results showed that although the deletion of CHU_2750 was not lethal to C. hutchinsonii, the mutant displayed an abnormal filamentous morphology, loose nucleoid, and obvious defects in the degradation of crystalline cellulose and cell motility. Further study indicated that the mutant displayed significantly decreased cell surface and intracellular endoglucanase activities but with β-glucosidase activities similar to the wild-type strain. Analyses by real-time quantitative PCR revealed that the transcription levels of many genes involved in cellulose degradation and/or cell motility were significantly downregulated in the mutant. In addition, we found that CHU_2750 was important for biofilm formation of C. hutchinsonii. The main extracellular components of the biofilm were analyzed, and the results showed that the mutant yielded significantly less exopolysaccharide but more extracellular DNA and protein than the wild-type strain. Collectively, our findings demonstrated that CHU_2750 is important for cellulose degradation, cell motility, and biofilm formation of C. hutchinsonii by modulating transcription of certain related genes, and it is the first identified transcriptional regulator in these processes of C. hutchinsonii. Our study shed more light on the mechanisms of cellulose degradation, cell motility, and biofilm formation by C. hutchinsonii. [ABSTRACT FROM AUTHOR]

Human activities have increased atmospheric nitrogen (N) deposition, in turn changing CO 2 emissions. Many studies concentrated on the relationships between the amount of N deposition and CO 2 emissions. However, how N forms affect CO 2 emissions is still poorly understood. A two-year field experiment was conducted to investigate the effects of N forms on CO 2 emissions in the coastal wetlands of the Yellow River Delta. The N forms consisted of nitrate (NaNO 3 ), ammonium (NH 4 Cl) and organic N (urea-N: glycin-N = 1: 1), and the level of N addition was 8 g N m −2 yr −1 . The CO 2 emissions were measured in the growing season from April to October. The results showed that three types of N addition stimulated CO 2 emissions ( P  < 0.05). Compared with the control treatment, nitrate, ammonium and organic N additions increased CO 2 emissions by 23.24%, 32.92% and 49.02%, respectively. Nitrate and ammonium additions produced similar and positive effects on CO 2 emissions, whereas organic N addition had larger and positive effects on CO 2 emissions than those of inorganic N addition ( P  < 0.05). This may be attributed to the following reasons. First, three types of N addition tended to increase soil β-glucosidase activity and Q 10 value of CO 2 emissions, but only organic N addition significantly enhanced soil β-glucosidase activity and Q 10 value ( P  < 0.05). Second, inorganic N addition had neutral and negative effects on the decomposition of soil organic carbon (SOC), whereas organic N addition increased SOC decomposition compared with control treatment ( P  < 0.05). Together, these findings highlight the significance of differentiating the influences of N forms on CO 2 emissions. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present work was to screen a pool of 75 yeasts belonging to the species Saccharomyces cerevisiae and Saccharomyces uvarum in order to select the strains endowed with β‐glucosidase activity. The first screening was a qualitative assay based on chromogenic substrates (arbutin and esculin). The second screening was the quantitative evaluation of the β‐glucosidase activity via a p‐nitrophenyl‐β‐ d‐glucopyranoside assay. The measurement was performed on three different cell preparations, including the extracellular compartment, the cell lysates and the whole cells. This study pointed out the high frequency of β‐glucosidase activity in S. uvarum strains. In particular, we retrieved three promising S. uvarum strains, CRY14, VA42 and GRAS14, featuring a high enzymatic activity, exploitable for winemaking. Significance and Impact of the Study: In yeasts, β‐glucosidase activity has been extensively described, especially in non‐Saccharomyces species, while there is only little evidence of this activity in strains belonging to the Saccharomyces species. In winemaking, β‐glucosidase plays essential roles in the hydrolysis of glyco‐conjugated precursors and the release of active aromatic compounds. This study provides new insights into the β‐glucosidase activity in strains belonging to Saccharomyces cerevisiae and Saccharomyces uvarum species, which are the most important strains in wine industry. Our results point out a marked enzymatic activity for the tested S. uvarum strains. These strains could be exploited for their potential ability to enhance the aroma profiles of wine. In addition, they could be potential sources for the commercial production of enzymes to be applied in winemaking. [ABSTRACT FROM AUTHOR]

A heteropolysaccharide BCP-2 was isolated from blackcurrant fruits by successively using D4006 resin, aqueous two phase system, and Sephadex G-100 column chromatography. Its inhibitory activities against α -glucosidase, α -amylase and glycation were investigated. BCP-2 was found to be composed of galacturonic acid, rhamnose, arabinose, xylose, mannose, glucose, and galactose in a molar ratio of 1.3:2.5:5.1:1.8:1.0:72.0:4.5 with molecular weight of 2.18 × 10 4  kDa. The glycosyl linkages of (1 → 3)- α - l -Rhamnose, (1 → 4)- β - d -Mannose, (1 → 6)- α - d -Galactose and (1 → 4)- α - d -Glucose were confirmed in BCP-2. BCP-2 had no triple-helix conformation and possessed a honeycomb structure with an irregular branching shape. BCP-2 showed moderate α -amylase inhibitory activity (37.93%) and clear α -glucosidase inhibitory activity (78.42%). The inhibitory effect of BCP-2 on α -amylase was reversible and exhibited a competitively inhibitory process. Besides, BCP-2 exerted more significant anti-glycation activities than aminoguanidine during 15 days of incubation. Specifically, the inhibitory abilities were more effective on the formation of dicarbonyl compounds (66.54%) and AGEs (70.24%) than that of Amadori products (37.03%). These results suggested that BCP-2 may be a potential anti-diabetic agent. [ABSTRACT FROM AUTHOR]

In ginseng, minor ginsenosides were more effective pharmacological properties than major ginsenosides. Therefore, finding bacteria that can convert major ginsenosides has been paying attention. Ginsenoside Rbl is one of major ginsenosides of ginseng and its biotransformation produces pharmacologically active compounds such as compound K. In this study, the isolation of bacterial strains from Vietnamese ginseng cultivated soil was carried out with the objective of evaluating their hydrolytic capacity for use in biotransformation of ginsenosides Rbl. In the screening of β-glucosidase producing bacteria, seven isolates exhibited black color zones on R2A agar medium containing esculine. Among seven isolates, strain E3 showed the highest ability biotransformation of ginsenosides Rbl in Luria-Bertani broth. Therefore, strain E3 was selected for further research. Biotransformation of Rbl was observed by using thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) with ginsenoside standards for comparison. We determined the optimal conditions for biotransformation of ginsenoside Rbl into the compound K of crude enzymes of strain E3 were at 30°C, pH 7,0 and 3 days. Ginsenoside Rbl was converted into compound K via ginsenoside Rd and F2. The analyses of 16S rRNA gene and phylogenetic tree indicated that strain E3 was closely related to Paenibacillus terrigena with 99,4% identity and formed a discrete cluster with type strain Paenibacillus terrigena A35T with high bootstrap support (99%), supporting strain E3 belonging to the species Paenibacillus terrigena. Physiological characteristics also supported strain E3 belonging to the genus Peanibacillus. This is the first report of biotransformation of ginsenosides using bacterial strains isolated from Vietnamese ginseng cultivated soil in Vietnam. Based on our the obtained results, strain E3 could be applied for the preparation of ginsenoside compound K for use in the cosmetic and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Cellulases and β-glucosidases (βGSD) are enzymes commonly used in the biofuel industry. In this study, smaller-sized variants were generated with aminopeptidase such that high catalytic capabilities were retained. Under the defined experimental conditions, the degree of hydrolysis was greater using cellulase substrates, compared to βGSD, based on ortho phthaldialdehyde (OPA) assay data (44% versus 15%). Proteolysis of cellulases was also evident based on sodium dodecyl sulfate polyacrylamide electrophoresis (SDS-PAGE) protein banding patterns seen after peptidase treatment. Residual cellulase activity was retained after peptidase hydrolysis (67% to 73%) based on standard filter paper assays. Peptidase treated cellulases and βGSD were then utilized for hydrolysis of alkaline-pretreated switchgrass (Panicum virgatum). Interestingly, the efficiency of the reaction, defined as milligrams of sugar produced per filter paper unit, was higher using truncated cellulases for bioprocessing reactions (~14%), especially in the absence of sodium azide. Conversely, incubation of βGSD with peptidase revealed minimal proteolysis with low impact on the efficiency of hydrolysis. [ABSTRACT FROM AUTHOR]

Reed contains a naturally-occurring gene resource base to resist cadmium stress. Transcriptome profiling is conducive to cloning the cadmium-tolerance genes in reed. Reed roots under cadmium stress were sampled, and the Illumina HiSeq™ 2500 transcriptome sequencing was performed. A total of 286,439 unigenes were obtained after de novo assembly. There were 22,304 up-regulating differentially expressed unigenes and 15,711 down-regulation. Two-level clustering formed an accurate heatmap to compare between expression fold-change classes and between treatment classes. The gene ontology terms were mainly enriched into biological regulation, metabolic process, response to stimulus, cell component, catalytic activity, proton-transporting two-sector ATPase and binding. Noticeably, the catalytic activity was mainly forwarded to oxidoreductase activity and antioxidant activity. There were obviously-enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, phenylpropanoid biosynthesis, phenylalanine metabolism, ribosome and photosynthesis. Beta-glucosidase EC: 3.2.1.21 was up-regulation in the phenylpropanoid biosynthesis pathway. Up-regulation of phenylpyruvate tautomerase EC: 5.3.2.1 catalyzes the production of 2-hydroxy-3-phenylpropanoate in the phenylalanine metabolism pathway. In the photosynthesis pathway, there was up-regulation of petN, petH, photosystems I/II, LHCA4 and LHCB3. The protein-protein interaction network showed that beta-glucosidase EC: 3.2.1.21 interacted with c129889_g1 and c115092_g3; up-regulation of photosystems II c111052 interacted with c93463_g1 and c121697_g3. Two up-regulating enzymes EC: 3.2.1.21 and EC: 5.3.2.1 may be the candidates to improve cadmium tolerance in reed. The photosynthesis with light-harvesting and electron transport plays important roles in reed cadmium tolerance. The interacting proteins c129889_g1, c115092_g3, c93463_g1 and c121697_g3 are putative to involve in cadmium tolerance. The current study is promising to provide the profile data for cloning these reed genes. [ABSTRACT FROM AUTHOR]

Bryophyllum pinnatum (Lam.) Oken leaves are employed as food and as traditional medicines. This study investigates the antioxidant activity (reducing power, DPPH, ABTS, FRAP, H2O2 scavenging ability and metal ion chelating), carbohydrate digesting enzymes activity and inhibitory activity of cholinergic enzyme of aqueous extract and fractions (n-hexane, ethyl acetate, n-butanol, residual aqueous fraction) of B. pinnatum leaves were investigated. Results showed that aqueous extract of B. pinnatum exhibited DPPH radical scavenging abilities, iron chelation, hydrogen peroxide scavenging abilities and reducing power (Fe3+-Fe2+). B. pinnatum aqueous extract also had considerably α-amylase and α-glucosidase inhibitory activities with IC50 values 149.20 ± 14.44 μg/mL and 126.15 ± 9.76 μg/mL respectively. Our findings indicated that ethyl acetate fraction contained a considerably higher (p < 0.05) amount of total phenolic, flavonoids, total antioxidant, FRAP, metal ion, ABTS and DPPH radical scavenging activity than other solvent fractions. Furthermore, the ethyl acetate fraction elicited a significantly higher (p < 0.05) inhibitory effects on α-glucosidase (IC50 = 70.90 ± 1.23 μg/ml), α-amylase (IC50 = 62.45 ± 1.22 μg/ml), acetylcholinesterase (AChE) (IC50 = 66.75 μg/mL) and butyrylcholinesterase (BChE) (IC50 = 62.97 μg/mL) activities than other fractions. Hence, B. pinnatum leaves were rich in biologically active components; thus, could be employed to formulate new plant-based pharmaceutical and nutraceutical drugs to improve human health. [ABSTRACT FROM AUTHOR]

Almond bitterness is the most important trait for breeding programs since bitter-kernelled seedlings are usually discarded. Amygdalin and its precursor prunasin are hydrolyzed by specific enzymes called β-glucosidases. In order to better understand the genetic control of almond bitterness, some studies have shown differences in the location of prunasin hydrolases (PH, the β-glucosidase that degrades prunasin) in sweet and bitter genotypes. The aim of this work was to isolate and characterize different PHs in sweet- and bitter-kernelled almonds to determine whether differences in their genomic or protein sequences are responsible for the sweet or bitter taste of their seeds. RNA was extracted from the tegument, nucellus and cotyledon of one sweet (Lauranne) and two bitter (D05–187 and S3067) almond genotypes throughout fruit ripening. Sequences of nine positive Phs were then obtained from all of the genotypes by RT-PCR and cloning. These clones, from mid ripening stage, were expressed in a heterologous system in tobacco plants by agroinfiltration. The PH activity was detected using the Feigl-Anger method and quantifying the hydrogen cyanide released with prunasin as substrate. Furthermore, β-glucosidase activity was detected by Fast Blue BB salt and Umbelliferyl method. Differences at the sequence level (SNPs) and in the activity assays were detected, although no correlation with bitterness was found. [ABSTRACT FROM AUTHOR]

Here, we have presented a technically simple and efficient method for preparing a continuous flow microreactor by employing immobilized β-glucosidase in a silica quartz capillary tube. Developing an immobilized enzyme layer on the inner wall of the capillary tube involved the modification of the inner wall using bifunctional crosslinking agents 3-aminopropyltriethoxysilane and glutaraldehyde before attaching β-glucosidase. The microreactor afforded unique reaction capacities compared with conventional batch operational configurations. These included enhanced pH and thermal stability during storage tests, increased conversion rates of cellobiose, and reduced product inhibition. The maximum conversion rate of soluble substrate cellobiose digestion in the microreactor was 76% at 50°C and pH 4.8 when the microreactor was operated continually over 10 h at a flow rate of 7 μL/min. This was markedly contrasting to the observed conversion rate of 56% when cellobiose was digested in a conventional batch mode under the same pH and temperature conditions. Reaction inhibition by glucose was significantly reduced in the microreactor. We postulate that the increased capacity of glucose to diffuse into the continual flowing media above the immobilized enzyme layer prevents glucose from reaching inhibitory concentrations at the substrate–enzyme interface. [ABSTRACT FROM AUTHOR]

This study was made to determine the impact of pesticides and wood vinegar, used to protect plants in wheat agroecosystems, on the Alkaline phosphatase and Beta-glucosidase soil enzymes' activities, comparatively. The study was made at the end of the production seasons of 2014-2015 and 2015-2016, on a field of winter wheat field under the ecologic conditions of Muç province, with four repetitions and in a fixed way according to the Randomized Block Experiment Pattern. The plant protection product applications in the study were: It was conducted as a pesticide application and control application, in which not any plant protection product (pesticide and wood vinegar) was applied with the wood vinegar dosages of 0.5% - 1% - 2% - 3% - 4% and 5% mL; corresponding to the pesticide application. In 2015, as the average enzyme activity for Alkaline phosphatase, the lowest value (9.409) was in pesticide and highest (11.262) was in 1% mL wood vinegar, and for Beta-glucosidase, the lowest value (4.329) was in 5% mL wood vinegar and the highest (4.829) was in 0.5% mL wood vinegar. In 2015, about the feature of enzyme activity; the interactions of Dose x Time x Type (P=0.372), Time x Type (P=0.957), Dose x Time (P=0.470) and the exclusive impact of time (P=0.146), were not found to be statistically significant, and the interaction of Dose x Type was found to be statistically significant (P=0.016). In 2016, it was found that the enzyme activity was increased after the application compared to before, in general, and the interactions of Dose x Time x Type (P=0.208), Dose x Time (P=0.799) and Dose x Type (P=0.345) were not found to be significant. It was found that the conducted pesticide and wood vinegar applications at different doses had impacts on the activities of Alkaline phosphatase and Beta-glucosidase, of the soil enzymes. It was also found that the wood vinegar did not affect the activities of these enzymes negatively and it was even promising in increasing the enzyme activities in some applications. [ABSTRACT FROM AUTHOR]

β-Glucosidase (BGL) from Bacillus subtilis was immobilized in polyacrylamide gel. Increasing the concentration of either acrylamide or bisacrylamide the yield of entrapped BGL was increased. The immobilized BGL showed 14.02% retention activity after storage for 25 days at 30°C. However, after three times repeatedly use of immobilized enzyme exhibited retention of 8.5% residual activity. Change in physicochemical properties such as viscosity, density and reducing sugar was identified while sugarcane juice treated with free and immobilized BGL. A remarkable decrease in viscosity of the treated sugarcane juice was observed. Though, an increase in reducing sugar was affirmed in free BGL and immobilized BGL. The absorption spectrum of sugarcane juice was also recovered raised by delivering the phenolic. These bioactive phenolic compounds could be retrieved after passing by a suitable adsorbent like charcoal and used as dietary supplements or other medicinal purposes. [ABSTRACT FROM AUTHOR]

Abstract: Optimization of cellulose enzymatic hydrolysis is crucial for cost‐effective bioethanol production from lignocellulosic biomass. Enzyme immobilization in solid support allows enzyme recycling for reuse, lowering hydrolysis costs. Graphene is a nanomaterial isolated in 2004, which possesses exceptional properties for biomolecule immobilization. This study evaluates the potential for β‐glucosidase recycling by immobilization on graphene nanosheets. Data reported here demonstrated that graphene‐immobilized β‐glucosidase can be recycled for at least eight cycles. Immobilization did not change the optimal temperature of catalysis and improved enzymatic stability upon storage. The role of glucose‐6‐phosphate on immobilized enzyme was also investigated, demonstrating that glucose‐6‐phosphate acts as a mixed‐type activator and improves storage stability of immobilized enzyme. Complete cellulose hydrolysis using graphene‐immobilized β‐glucosidase in the presence of glucose‐6‐phosphate resulted in greatly improved hydrolysis rates, demonstrating the potential of this strategy for biomass hydrolysis. [ABSTRACT FROM AUTHOR]

The β-glucosidase and esterase activities of 31 O. oeni strains were evaluated by fluorimetric methods. The level and distribution among intact cells and supernatant of both β-glucosidase and esterase activity in MRS broth were strongly strain-dependent. In the wine, hydrolytic activities were detected only in the intact cells and their level was related to the cell growth and malolactic activity. Increasing concentration of ethanol (from 12 to 15 (% v/v)) and molecular SO 2 (from 0.2 to 0.6 mg L −1 ) led to a slowdown of bacterial growth and malolactic fermentation (MLF). An inhibitory effect of the lowest doses of molecular sulphur dioxide on both β-glucosidase and esterase activity was highlighted. A synergistic effect among SO 2 and ethanol on hydrolytic activities was observed during MLF. Only one strain was able to complete MLF and to produce both hydrolytic activities also in the harshest conditions. [ABSTRACT FROM AUTHOR]

The thermostable GH3 β-glycosidase (Tpebgl3) from Thermotoga petrophila DSM 13995 was immobilized on macroporous resin NKA-9 modified with polyethylenimine (PEI) and glutaraldehyde (named NKA-9II). The properties of NKA-9II were as follows: the optimal conditions were the same as that of the free enzyme (pH 5.0; 90 °C), and the highest activity with cellobiose as the substrate approached 1.7 U/g; the thermostability, pH stability and glucose tolerance were greatly improved; the residual activity of NKA-9II was 68% of the initial activity at the end of 10 repeated cycles. Moreover, it was found that 2 mM Zn 2+ increased the relative activity of NKA-9II to 192% and 199% with cellobiose and p -nitrophenyl-β- d -glucopyranoside ( p NPG) as substrates, respectively. Meanwhile, Zn 2+ could greatly improve the reusability, high-temperature stability, and glucose tolerance of NKA-9II. In particular, 84% of the residual activity of NKA-9II with 2 mM Zn 2+ was retained, which was 21% higher than that with free metal ion after incubation at 85 °C for 7 h; when the glucose concentration was 400 mM, the free Tpebgl3 was completely inactivated, and NKA-9II with 2 mM Zn 2+ maintained 63% of its initial activity, which was 19.5% higher than the activity of NKA-9II in the absence of Zn 2+ . [ABSTRACT FROM AUTHOR]

Purpose: The carbon sink function of peatlands is primarily driven by a higher production than decomposition of the litter Sphagnum mosses. The observed increase of vascular plants in peatlands could alter the decomposition rate and the carbon (C) cycle through a litter mixing effect, which is still poorly studied. Here, we examine the litter mixing effect of a peat moss (Sphagnum fallax) and two vascular plants (Pinus uncinata and Eriophorum vaginatum) in the field and laboratory-based experiment.Materials and methods: During the laboratory incubation, mass loss, CO2 production, and dissolved organic carbon concentration were periodically monitored during 51 days. The collected data were then processed in a C dynamics model. The calculated enzymatic activity was correlated to the measured β-glucosidase activity in the litter. In the field experiment, mass loss and CO2 production from litter bags were annually measured for 3 years.Results and discussion: Both laboratory and field experiments clearly show that the litter mixture, i.e., Sphagnum-Pinus-Eriophorum, had a synergistic effect on decomposition by enhancing the mass loss. Such enhanced mass loss increased the water extractable C and CO2 production in the litter mixture during the laboratory experiment. The synergistic effect was mainly controlled by the Sphagnum-Eriophorum mixture that significantly enhanced both mass loss and CO2 production. Although the β-glucosidase activity is often considered as a major driver of decomposition, mixing the litters did not cause any increase of the activity of this exo-enzyme in the laboratory experiment suggesting that other enzymes can play an important role in the observed effect.Conclusions: Mixing litters of graminoid and Sphagnum species led to a synergistic effect on litter decomposition. In a context of vegetation dynamics in response to environmental change, such a mixing effect could alter the C dynamics at a larger scale. Identifying the key mechanisms responsible for the synergistic effect on litter decomposition, with a specific focus on the enzymatic activities, is crucial to better predict the capacity of peatlands to act as C sinks. [ABSTRACT FROM AUTHOR]

This study characterized a 50 kDa β-glucosidase (BGL50) produced by the thermophilic fungus Myceliophthora thermophila M.7.7 in solid state cultivation using a mixture of (1:1) sugarcane bagasse and wheat bran. The crude extract zymogram showed two isoforms of β-glucosidase with approximately 50 and 200 kDa, which were separated by gel filtration chromatography. The characterization of BGL50 showed optimum activity at 60 °C and pH 5.0 when 4-nitrophenyl β-D-glucopyranoside (pNPG) was used as the substrate, whereas when using cellobiose, the highest activity was observed at 50 °C and pH 4.5. Several ions and reagents produced different effects on the enzyme activity depending on the substrate and there was complete inhibition with Cu 2+ and Fe 3+ for both substrates. In addition, nine phenolic compounds showed no inhibitory effects on the enzyme, a significant feature since β-glucosidase is used for the saccharification of lignocellulosic biomass that generates several phenolic compounds. Kinetic studies revealed competitive inhibition by glucose when pNPG was used, with a K i value of 1.5 mM and a significantly lower K m (0.52 mM) than for cellobiose (8.50 mM). The thermodynamic parameters showed that BGL50 is very stable at 60 °C displaying a half-life of 855.6 min but it is easily denatured above this temperature. The results emphasize the importance of investigating potential β-glucosidases based on cellobiose instead of using only pNPG since, in the industrial process, the enzyme will act on this natural substrate. In addition, understanding the thermostability of the enzyme is an important contribution to enzyme technology. [ABSTRACT FROM AUTHOR]

The enzyme, β-glucosidase (β-Glu; EC 3.2.1.21), is a commercially important enzyme. First, β-Glu enzyme and specific activity were screened in total of 54 strains. In these strains, β-Glu-specific enzyme activity was assessed varying from 0.250 to 3.000 U/mg. Next, β-Glu enzyme belonging to the strains (Lactobacillus rhamnosus EA1 and Lactobacillus casei SC1) that exhibited high β-Glu-specific enzyme activity optimization were done. In these strains, optimum pH was 7.5, optimum temperature was 30°C, and optimum buffer was potassium phosphate. Then, the strains that displayed high β-Glu-specific enzyme activity were decided to hydrolyze the isoflavone glucosides using high-pressure liquid chromatography. Finally, following the partial purification of β-Glu enzyme, its molecular weight was detected to be approximately 78 K. Ultimately, in the present study, β-Glu enzyme acquired from L. casei SC1 strain became prominent because its activity was higher. It did not lose its activity under different environmental conditions and demonstrated high hydrolyzing the isoflavone. [ABSTRACT FROM AUTHOR]

Beta-glucosidase (BGL) is a rate-limiting enzyme for cellulose hydrolysis as it acts in the final step of lignocellulosic biomass conversion to convert cellobiose into glucose, the final end product. Most of the fungal strains used for cellulase production are deficient in BGL hence BGL is supplemented into cellulases to have an efficient biomass conversion. Genetic engineering has enabled strain modification to produce BGL optimally with desired properties to be employed for biofuel applications. It has been cloned either directly into the host strains lacking BGL or into another expression system, to be overexpressed so as to be blended into BGL deficient cellulases. In this article, role of genetic engineering to overcome BGL limitations in the cellulase cocktail and its significance for biofuel applications has been critically reviewed. [ABSTRACT FROM AUTHOR]

Members of the genus Caldicellulosiruptor are the most thermophilic cellulolytic bacteria so far described and are capable of efficiently utilizing complex lignocellulosic biomass without conventional pretreatment. Previous studies have shown that accumulation of high concentrations of cellobiose and, to a lesser extent, cellotriose, inhibits cellulase activity both in vivo and in vitro and high concentrations of cellobiose are present in C. bescii fermentations after 90 h of incubation. For some cellulolytic microorganisms, β- d-glucosidase is essential for the efficient utilization of cellobiose as a carbon source and is an essential enzyme in commercial preparations for efficient deconstruction of plant biomass. In spite of its ability to grow efficiently on crystalline cellulose, no extracellular β- d-glucosidase or its GH1 catalytic domain could be identified in the C. bescii genome. To investigate whether the addition of a secreted β- d-glucosidase would improve growth and cellulose utilization by C. bescii, we cloned and expressed a thermostable β- d-glucosidase from Acidothermus cellulolyticus (Acel_0133) in C. bescii using the CelA signal sequence for protein export. The effect of this addition was modest, suggesting that β- d-glucosidase is not rate limiting for cellulose deconstruction and utilization by C. bescii. [ABSTRACT FROM AUTHOR]

A Gram-reaction-negative, aerobic, nonmotile, nonspore-forming, and rod-shaped bacterial strain designated Gsoil 3017 was isolated from soil of ginseng field and investigated by phenotypic and phylogenetic analyses. Strain Gsoil 3017 grew at 10-37 °C (optimal growth at 30 °C) and at pH 5.5-8.0 (optimal growth at pH 7) on R2A and nutrient agar without additional NaCl as a supplement. Strain Gsoil 3017 possessed β-glucosidase activity, which was responsible for its ability to transform ginsenosides Rb, Rc, and Rd (the three dominant active components of ginseng) to F and C-K, respectively. Based on 16S rRNA gene phylogeny, the novel strain represents a new branch within the genus Mucilaginibacter family Sphingobacteriaceae, and clusters with Mucilaginibacter frigoritolerans FT22 (95.6%) and Mucilaginibacter gotjawali SA3-7 (95.6%). The G+C content of the genomic DNA was 48.7%. The predominant respiratory quinone was MK-7, and the major fatty acids were iso-C, iso-C 3-OH, and summed feature 3 (comprising C ω6 c and/or C ω7 c). The major polar lipid was phosphatidylethanolamine. Strain Gsoil 3017 could be differentiated genotypically and phenotypically from other type strains of the genus Mucilaginibacter. The isolate therefore represents a novel species, for which the name Mucilaginibacter ginsenosidivorans sp. nov. is proposed, with the type strain Gsoil 3017 (=KACC 14954 = JCM 17081). [ABSTRACT FROM AUTHOR]

The non-lysosomal glucosylceramidase GBA2 catalyzes the hydrolysis of glucosylceramide to glucose and ceramide. Loss of GBA2 function results in accumulation of glucosylceramide. Mutations in the human GBA2 gene have been associated with hereditary spastic paraplegia (HSP) and autosomal-recessive cerebellar ataxia (ARCA). Patients suffering from these disorders exhibit impaired locomotion and neurological abnormalities. GBA2 mutations found in these patients have been proposed to impair GBA2 function. However, the molecular mechanism underlying the occurrence of mutations in the GBA2 gene and the development of locomotor dysfunction is not well-understood. In this review, we aim to summarize recent findings regarding mutations in the GBA2 gene and their impact on GBA2 function in health and disease. [ABSTRACT FROM AUTHOR]

Bacillus licheniformis CGMCC 2876, an aerobic spore-forming bacterium, produces a polysaccharide bioflocculant that is biodegradable and harmless. The present study determined that β-glucosidase played a negative role in bioflocculant synthesis. The gene encoding β-glucosidase was cloned and expressed in Escherichia coli BL21. This gene consists of 1437 bp and encodes 478 amino acid residues. The recombinant β-glucosidase (Bgl.bli1) was purified and showed a molecular mass of 53.4 kDa by SDS-PAGE. The expression and reaction conditions of Bgl.bli1 were optimized; the activity of β-glucosidase reached a maximum at 45.44 U/mL. Glucose clearly inhibited the activity of β-glucosidase. The purified recombinant Bgl.bli1 hydrolysed polysaccharide bioflocculant in vitro and synergised with other cellulases. The ability of Bgl.bli1 to hydrolyse polysaccharide bioflocculant was the reason for the decrease in flocculating activity and indicated the utility of this enzyme for diverse industrial processes. [ABSTRACT FROM AUTHOR]

Phenolic composition of virgin olive oil is determined by the enzymatic and/or chemical reactions that take place during olive fruit processing. Of these enzymes, β-glucosidase activity plays a relevant role in the transformation of the phenolic glycosides present in the olive fruit, generating different secoiridoid derivatives. The main goal of the present study was to characterize olive fruit b-glucosidase genes and enzymes responsible for the phenolic composition of virgin olive oil. To achieve that, we have isolated an olive β-glucosidase gene from cultivar Picual (OepGLU), expressed in Nicotiana benthamiana leaves and purified its corresponding recombinant enzyme. Western blot analysis showed that recombinant OepGLU protein is detected by an antibody raised against the purified native olive mesocarp β-glucosidase enzyme, and exhibits a deduced molecular mass of 65.0 kDa. The recombinant OepGLU enzyme showed activity on the major olive phenolic glycosides, with the highest levels with respect to oleuropein, followed by ligstroside and demethyloleuropein. In addition, expression analysis showed that olive GLU transcript level in olive fruit is spatially and temporally regulated in a cultivar-dependent manner. Furthermore, temperature, light and water regime regulate olive GLU gene expression in olive fruit mesocarp. All these data are consistent with the involvement of OepGLU enzyme in the formation of the major phenolic compounds present in virgin olive oil. [ABSTRACT FROM AUTHOR]

Developing value-added lignin-based biomaterials for enzyme immobilization has drawn great attention. This study developed a cost-effective and eco-friendly one-pot strategy to synthesize the rod-like lignin@zeolitic imidazolate framework-8 (ZIF-8) hybrid nanomaterial by using lignin derived from lignocellulosic biofuel production. The incorporation of lignin into the ZIF-8 network not only altered the morphology, but also modified the surface properties of the material, making it an ideal support for enzyme immobilization. The synthesized nanoscale hybrid materials were used to immobilize beta-glucosidase (BG) with high immobilization capacity and about 92–166 mg/g of BG was immobilized through physical adsorption. The immobilized BG exhibited good stability, catalytic activity and recycling properties, and was reused under acidic conditions for more than 8 cycles with more than 60% activity kept. The as-prepared hybrid material can serve as a great carrier for immobilizing various biomolecules. • A one-pot strategy was developed to synthesize the rod-like lignin@ZIF-8. • The morphology and surface properties of lignin@ZIF-8 were characterized. • The immobilization capacity of lignin@ZIF-8 for beta-glucosidase (BG) was about 92–166 mg/g. • The relative activity of immobilized BG was more than 60% after 8 times reuse. [ABSTRACT FROM AUTHOR]