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Background/Objectives: Sorghum bicolor is a source of many bioactive components, such as polyphenols. Those components are present mainly in its bran, often removed in industrial processes through decortication. In that sense, this work aimed to analyze the polyphenol content, especially free flavonoids, from the bran of a newly developed variety compared to other commercially available varieties. Methods: The samples were white sorghum TDN® Sorgho, red sorghum Mini Sorgho, and the newly developed red sorghum RILN-156. First, decortication was conducted to obtain the bran samples, which were triturated and then sieved. The use of colorimetric methods allowed the general quantification of the polyphenolic components. First, the polyphenol content was extracted using 70% methanol. Then, the samples' total phenolic content, total flavonoid content, total tannin content, total anthocyanin content, and antioxidant potential were determined. To analyze the different components and identify the free flavonoids, an untargeted metabolomics analysis (with liquid chromatography coupled with mass spectrometer (LC/MS) and capillary electrophoresis coupled with a mass spectrometer (CE/MS)) was performed. Results: The results have shown that apart from anthocyanin and tannin, the newly developed variety, RILN-156, presented the highest concentration of polyphenolic content, including a higher antioxidant capacity. The exploratory analysis identified 19 flavonoids within the samples, with galangin and daidzein being the most abundant ones. Conclusions: These results show a promising finding for using this newly developed sorghum variety (RILN-156) industrially and further investigating its health benefits. They also elucidate the differences between colored sorghum within themselves and with white sorghum varieties. [ABSTRACT FROM AUTHOR]

CbpA, the scaffolding protein of Clostridium cellulovorans cellulosomes, possesses one family 3 cellulose binding domain, nine cohesin domains, and four hydrophilic domains (HLDs). Among the three types of domains, the function of the HLDs is still unknown. We proposed previously that the HLDs of CbpA play a role in attaching the cellulosome to the cell surface, since they showed some homology to the surface layer homology domains of EngE. Several recombinant proteins with HLDs (rHLDs) and recombinant EngE (rEngE) were examined to determine their binding to the C. cellulovorans cell wall fraction. Tandemly linked rHLDs showed higher affinity for the cell wall than individual rHLDs showed. EngE was shown to have a higher affinity for cell walls than rHLDs have. C. cellulovorans native cellulosomes were found to have higher affinity for cell walls than rHLDs have. When immunoblot analysis was carried out with the native cellulosome fraction bound to cell wall fragments, the presence of EngE was also confirmed, suggesting that the mechanism anchoring CbpA to the C. cellulovorans cell surface was mediated through EngE and that the HLDs play a secondary role in the attachment of the cellulosome to the cell surface. During a study of the role of HLDs on cellulose degradation, the mini-cellulosome complexes with HLDs degraded cellulose more efficiently than complexes without HLDs degraded cellulose. The rHLDs also showed binding affinity for crystalline cellulose and carboxymethyl cellulose. These results suggest that the CbpA HLDs play a major role and a minor role in C. cellulovorans cellulosomes. The primary role increases cellulose degradation activity by binding the cellulosome complex to the cellulose substrate; secondarily, HLDs aid the binding of the CbpA/cellulosome to the C. cellulovorans cell surface.

Glucose sensitivity and pH and thermal stabilities of Trichoderma reesei Cel1A (Bgl II) were improved by site-directed mutagenesis of only two amino acid residues (L167W or P172L) at the entrance of the active site. The Cel1A mutant showed high glucose tolerance (50% of inhibitory concentration = 650 mM), glucose stimulation (2.0 fold at 50 mM glucose), and enhanced specific activity (2.4-fold) compared with those of the wild-type Cel1A. Furthermore, the mutant enzyme showed stability at a wide pH range of 4.5–9.0 and possessed high thermal stability up to 50°C with 80% of the residual activities compared with the stability seen at the pH range of 6.5–7.0 and temperatures of up to 40°C in the wild-type Cel1A. Kinetic studies for hydrolysis revealed that the Cel1A mutant was competitively inhibited by glucose at similar levels as the wild-type enzyme. Additionally, the mutant enzyme exhibited substrate inhibition, which gradually disappeared with an increasing glucose concentration. These data suggest that the glucose stimulation was caused by relieve the substrate inhibition in the presence of glucose. To conclude, all the properties improved by the mutagenesis would be great advantages in degradation of cellulosic biomass together with cellulases. [ABSTRACT FROM AUTHOR]

Neo-fermented buckwheat sprouts (neo-FBS) contain angiotensin-converting enzyme (ACE) inhibitors and vasodilators with blood pressure-lowering (BPL) properties in spontaneously hypertensive rats (SHRs). In this study, we investigated antihypertensive mechanisms of six BPL peptides isolated from neo-FBS (FBPs) by a vasorelaxation assay and conventional in vitro, in vivo, and a new ex vivo ACE inhibitory assays. Some FBPs demonstrated moderate endothelium-dependent vasorelaxation in SHR thoracic aorta and all FBPs mildly inhibited ACE in vitro. Orally administered FBPs strongly inhibited ACE in SHR tissues. To investigate detailed ACE-inhibitory mechanism of FBPs in living body tissues, we performed the ex vivo assay by using endothelium-denuded thoracic aorta rings isolated from SHRs, which demonstrated that FBPs at low concentration effectively inhibited ACE in thoracic aorta tissue and suppressed angiotensin II-mediated vasoconstriction directly associated with BPL. These results indicate that the main BPL mechanism of FBP was ACE inhibition in living body tissues, suggesting that high FBP's bioavailability including absorption, tissue affinity, and tissue accumulation was responsible for the superior ACE inhibition in vivo. We propose that our ex vivo assay is an efficient and reliable method for evaluating ACE-inhibitory mechanism responsible for BPL activity in vivo. [ABSTRACT FROM AUTHOR]

The article highlights the study of the genetic coding for cellobiohydrolase II from the white rot basidiomycete, Irpex lacteus MC-2 and its expression in pichia pastoris. The derived amino acid sequences exposed a significant structure comprised of protein binding domain owning to glycosyl hydrolases family. The primary objective of the study is to help developing effective cellulosic biomass degradation usiing with rot fungi enzymes.

The article examines the structure and reactivity of an endo-β-1,4-glucanase, a cellulose-degrading enzyme. The enzymes were isolated from a strong cellulolytic fungus Trametes hirsuta. The whole sequence of the enzymes showed high homology with the family 4 glycoside hydrolase. The authors also discuss polymerase chain reaction-based cloning cDNA and gene of endoglucanase, amino acid sequencing and expression, and purification of the recombinant enzyme.

Examines the isolation of the cen1 gene coding for an endoglucanase I from white rot fungus Irpex lacteus strain MC-2. Gene cloning of the endoglucanase; Expression of the gene in the heterologous host Saccharomyces cerevesiae; Synergistic effect between the recombinant enzymes for the degradation of crystalline cellulose.

In our previous paper, cotton fabrics which had been modified by carboxymethylation so as to have the degree of substitution of 0.02-M. 16 were. treated with a commercial cellulase preparation. The modification by carboxymethylation for cotton fabrics apparently inhibited weight loss activity and saccharification activity of cellulase. In this study, by scanning electron microscopy, we observed morphological changes of fiber surface of modified cotton fabrics treated with a commercial cellulase preparation. For unmodified cotton fabrics, deep bias cracks were produced and clear fibrillar layers appeared on the fiber surface by synergistic reaction of cellulase components. On the other hand, for cotton fabrics modified by carboxymethylation, we observed inhibition of catalytic reaction of some cellulase components, as a result of no deep cracks and no appearance of fibril layers on fibers. In addition, we confirmed, by measurements of FT-IR spectra and K/S values of fabrics dyed with a basic dye, that carboxymethyl groups in modified cotton fabrics remained even after treatment with cellulase. From these results, it is suggested that the change in the activity of each cellulase component on modified cotton can affect the synergistic action of cellulases, and consequently the morphology of fiber surface of modified cotton changes compared with unmodified cotton. [ABSTRACT FROM AUTHOR]

Examines the mode of action of cellulases on dyed cotton with a reactive dye. Inhibition of the weight loss activity and saccharification activity of cellulase; Capability of the cellular on dyed cotton in affecting the synergistic action of cellulases.

Cotton fabrics modified by carboxymethylation to the degree of substitution (DS) of 0.02-M. 16 were separated into the salt-type CM-Cotton-Na with more water swelling and the acid-type CM-Cotton-H with less water swelling. The two types of cotton fabrics were treated with a commercially available cellulase product. For CM-Cotton-Na and CM-Cotton-H, the weight loss and the saccharification activities of the cellulase decreased with DS of 0.10 or less. The modification by carboxymethylation for cotton fabrics inhibited apparently the catalytic reaction of the cellulase. For CM-Cotton-Na and CM-Cotton-H, the cellulase showed the minimum value of the weight loss activity at DS of 0.10 and that of the saccharification activity at DS of 0.14. For CM-Cotton-Na, the cellulase exhibited larger value of the weight loss activity and smaller value of the saccharification activity at DS of 0.16 compared to the unmodified cotton fabric. We discussed that the endo-type cellulase attacked positively to CM-Cotton-Na with DS of 0.10 or more because of its more water swelling, but attacked negatively to CM-Cotton-H because of its less water swelling. On the other hand, the exo-type cellulase was inhibited to attack the modified cotton fabrics with DS of 0010 or more. [ABSTRACT FROM AUTHOR]

A novel plant gene CFL1 was cloned from cotton (Gossypium hirsutum L.) fibers by expressed sequence tag (EST) database searching and 5′-RACE (rapid amplification of cDNA ends). This gene shows sequence homology with FKS1 which has been identified as the putative catalytic subunit of the yeast β-1,3-glucan synthase. It encodes a protein (CFL1p) of 219 kDa with 13 deduced transmembrane helices and 2 large hydrophilic domains, one of which is at the N-terminus and the other in the internal region of the polypeptide. CFL1 displays 21% identity and 41% similarity to FKS1 at the amino acid level over its entire length, with 31% identity and 52% similarity for the hydrophilic central domain. Using RNA and protein blot analysis, CFL1 was found to be expressed at higher levels in cotton fibers during primary wall development. CFL1 also had a strong expression in young roots. Using a calmodulin (CaM)-gel overlay assay, the hydrophilic N-terminal domain of CFL1p was shown to bind to CaM, while the hydrophilic central domain did not. A putative CaM-binding domain, 16 amino acids long, was predicted in the hydrophilic N-terminal domain. Moreover, a product-entrapment assay demonstrated that a protein associated with an in vitro-synthesized callose pellet could be labeled by anti-CFL1 antibodies. Our finding suggests that CFL1 is a putative plant homolog of the yeast β-1,3-glucan synthase subunit FKS1 and could be involved in callose synthesis. [ABSTRACT FROM AUTHOR]

Reports on the evidence that endo-1,4-beta-glucanases act on cellulose in suspension-cultured poplar cells. Release of an endo-1,4,-beta-glucanase in the extracellular culture medium and the other localized in their walls; Levels of cell DNA clones; Accumulation of the mRNA correlated with the solubilization of cello-oligosaccharides.

In this study, regenerated celluloses were prepared from microcrystalline cellulose (MCC) by treatment with three ionic liquids (ILs) having 1-ethyl-3-methylimidazolium (Emim) as the cation, and the IL N-(2-methoxyethyl)-N,N-diethyl-N-methylammonium alanine ([N [sub 221ME] ][Ala]), where the amino acid moiety is the anion. The crystal form of cellulose was transformed from cellulose I to cellulose II by dissolution with an IL and regeneration with anti-solvent. However, the crystallinity of the regenerated cellulose was different; the disordered chain region was increased in the order of [N [sub 221ME] ][Ala] < [Emim][OAc] < [Emim][DEP] < [Emim][Cl]. The monocomponent cellulase, especially endoglucanase, showed high hydrolyzing activity for regenerated cellulose compared with untreated cellulose. Furthermore, the degree of increase of hydrolyzing activity was almost coincident with the order of crystallinity. For the effective hydrolysis of cellulose treated with an IL, it is necessary to prepare the cellulase mixture containing an adequate ratio of each cellulase component according to crystal allomorph and the crystallinity of regenerated cellulose. Dissolution of microcrystalline cellulose with ionic liquid and regeneration of cellulose by adding poor solvent cause the change of crystal allomorph and crystallinity of cellulose. These structural differences affect the adsorption ability of cellulase on the surface of regenerated cellulose and the enzymatic digestibility by monocomponent cellulase. [ABSTRACT FROM AUTHOR]

Acetylcholine (AcCh) is a major neurotransmitter and an agonist of nicotinic and muscarinic receptors in non-neuronal systems. Artificially synthesized lactoylcholine (LaCh) has potent nicotinic activity equal to that of AcCh. In this study, we report the isolation and purification of natural AcCh and LaCh from a lactic-fermented food known to reduce blood pressure. To our knowledge, we are the first to isolate natural LaCh. The choline esters were isolated using a novel purification procedure combining a weak cation-exchange cartridge with ODS and pentafluorophenyl HPLC columns, and the structure of LaCh was identified via various analyses. Assessment of d - and l -LaCh showed that the isolated LaCh was an enantiomer mixture with a D/L ratio of 1.6. d -LaCh induced vasorelaxation of thoracic aortas from spontaneously hypertensive rats (EC 50 = 3.83 × 10 −7 M), while l -LaCh did not. Our results suggest that choline esters could be new functional ingredients in lactic-fermented foods. [ABSTRACT FROM AUTHOR]