scholarly journals Effect of B-Glucosidase Activity on the Vanillin Enzymatic Formation by Using Rumen Liquid for Cell Walls Degradation

2013 ◽  
Vol 2 (2) ◽  
pp. 65 ◽  
Author(s):  
Vita Paramita ◽  
Mohamad Endy Yulianto

<p>This work proposed a study of direct enzymatic of vanillin formation by using rumen fluid which has enzymatic capability for tissue disruption of vanilla green pods to avoid the curing process. Application of enzymes during the formation of vanilla aromas and flavors and its extraction present nice opportunity to improve productivity, as the enzymatic reaction possibly substitute the microbial process in the traditional fermentation. Glucovanillin, the precursor of vanillin, contacted with the B-glucosidase in the green pods by destructing the cell wall. Liquid rument was providing enzyme for cell wall degradation. The contact of glucovanillin and B-glucosidase lead the hydrolysis of glucovanillin into vanillin. The amounts of glucovanillin and vanillin were examined by using HPLC analysis. The identification of vanillin was investigated by using liquid chromatography-mass spectrofotometry. Vanillin content of vanilla green pods was found higher in which by treating the vanilla green pods at 30°C.</p>

2019 ◽  
Vol 1 (1) ◽  
pp. 26-29
Author(s):  
Indah Hartati ◽  
Pradipta Risma Rukma Ardi ◽  
Muhammad Milzam ◽  
Vita Paramita

This work proposed a study of a direct enzymatic of vanillin formation by using rumen liquid which has enzymatic capability for tissue disruption of vanilla green pods to avoid the curing process. Application of enzymes during the formation of vanilla aromas and its extraction present nice opportunity to improve productivity, as the enzymatic reaction possibly substitute the microbial process in the traditional fermentation. Green vanilla pods were applied for the direct enzymatic extraction of vanillin, while liquid rument provide cell wall degrading enzyme in order to support the hydrolysis process (destruction) of cell wall. Glucovanillin were contacted with the β-glucosidase in the green pods due to the desruction of the cell wall, followed by the formation of glucovanillin into vanillin. Vanillin content of vanilla green pods was found higher in which by treating the vanilla green pods at 30 °C.


2000 ◽  
Vol 66 (9) ◽  
pp. 3807-3813 ◽  
Author(s):  
S. S. Lee ◽  
J. K. Ha ◽  
K.-J. Cheng

ABSTRACT To assess the relative contributions of microbial groups (bacteria, protozoa, and fungi) in rumen fluids to the overall process of plant cell wall digestion in the rumen, representatives of these groups were selected by physical and chemical treatments of whole rumen fluid and used to construct an artificial rumen ecosystem. Physical treatments involved homogenization, centrifugation, filtration, and heat sterilization. Chemical treatments involved the addition of antibiotics and various chemicals to rumen fluid. To evaluate the potential activity and relative contribution to degradation of cell walls by specific microbial groups, the following fractions were prepared: a positive system (whole ruminal fluid), a bacterial (B) system, a protozoal (P) system, a fungal (F) system, and a negative system (cell-free rumen fluid). To assess the interactions between specific microbial fractions, mixed cultures (B+P, B+F, and P+F systems) were also assigned. Patterns of degradation due to the various treatments resulted in three distinct groups of data based on the degradation rate of cell wall material and on cell wall-degrading enzyme activities. The order of degradation was as follows: positive and F systems > B system > negative and P systems. Therefore, fungal activity was responsible for most of the cell wall degradation. Cell wall degradation by the anaerobic bacterial fraction was significantly less than by the fungal fraction, and the protozoal fraction failed to grow under the conditions used. In general, in the mixed culture systems the coculture systems demonstrated a decrease in cellulolysis compared with that of the monoculture systems. When one microbial fraction was associated with another microbial fraction, two types of results were obtained. The protozoal fraction inhibited cellulolysis of cell wall material by both the bacterial and the fungal fractions, while in the coculture between the bacterial fraction and the fungal fraction a synergistic interaction was detected.


2000 ◽  
Vol 66 (8) ◽  
pp. 3174-3179 ◽  
Author(s):  
M. Carmen Martínez-Cuesta ◽  
Jan Kok ◽  
Elisabet Herranz ◽  
Carmen Peláez ◽  
Teresa Requena ◽  
...  

ABSTRACT The bacteriocin produced by Lactococcus lactis IFPL105 is bactericidal against several Lactococcus andLactobacillus strains. Addition of the bacteriocin to exponential-growth-phase cells resulted in all cases in bacteriolysis. The bacteriolytic response of the strains was not related to differences in sensitivity to the bacteriocin and was strongly reduced in the presence of autolysin inhibitors (Co2+ and sodium dodecyl sulfate). When L. lactis MG1363 and its derivative deficient in the production of the major autolysin AcmA (MG1363acmAΔ1) were incubated with the bacteriocin, the latter did not lyse and no intracellular proteins were released into the medium. Incubation of cell wall fragments of L. lactisMG1363, or of L. lactis MG1363acmAΔ1 to which extracellular AcmA was added, in the presence or absence of the bacteriocin had no effect on the speed of cell wall degradation. This result indicates that the bacteriocin does not degrade cell walls, nor does it directly activate the autolysin AcmA. The autolysin was also responsible for the observed lysis of L. lactis MG1363 cells during incubation with nisin or the mixture of lactococcins A, B, and M. The results presented here show that lysis of L. lactis after addition of the bacteriocins is caused by the resulting cell damage, which promotes uncontrolled degradation of the cell walls by AcmA.


2019 ◽  
Vol 30 (4) ◽  
pp. 441-452 ◽  
Author(s):  
Allison E. Hall ◽  
Mark D. Rose

During mating, Saccharomyces cerevisiae cells must degrade the intervening cell wall to allow fusion of the partners. Because improper timing or location of cell wall degradation would cause lysis, the initiation of cell fusion must be highly regulated. Here, we find that yeast cell fusion is negatively regulated by components of the cell wall integrity (CWI) pathway. Loss of the cell wall sensor, MID2, specifically causes “mating-induced death” after pheromone exposure. Mating-induced death is suppressed by mutations in cell fusion genes ( FUS1, FUS2, RVS161, CDC42), implying that mid2Δ cells die from premature fusion without a partner. Consistent with premature fusion, mid2Δ shmoos had thinner cell walls and lysed at the shmoo tip. Normally, Cdc42p colocalizes with Fus2p to form a focus only when mating cells are in contact (prezygotes) and colocalization is required for cell fusion. However, Cdc42p was aberrantly colocalized with Fus2p to form a focus in mid2Δ shmoos. A hyperactive allele of the CWI kinase Pkc1p ( PKC1*) caused decreased cell fusion and Cdc42p localization in prezygotes. In shmoos, PKC1* increased Cdc42p localization; however, it was not colocalized with Fus2p or associated with cell death. We conclude that Mid2p and Pkc1p negatively regulate cell fusion via Cdc42p and Fus2p.


1996 ◽  
Vol 74 (12) ◽  
pp. 1974-1981 ◽  
Author(s):  
C. Batisse ◽  
P. J. Coulomb ◽  
C. Coulomb ◽  
M. Buret

The changes in texture of fruits during ripening are linked to cell wall degradation involving synthesis and degradation of polymers. An increase in pectin solubility leads to cell sliding and an elastic aspect of tissues. The biochemical cell wall process differs between soft and crisp fruits originating from a same cultivar but cultivated under different agroclimatic conditions. Although the proportions of cell wall material are similar, the composition and structure of the two cell walls are very different at maturity. A solubilization of the middle lamella and a restructuration of the primary cell walls arising from the cells separation is observed in crisp fruits. In contrast, the middle lamella of the soft fruits is better preserved and the primary cell walls are thin and show degradation bags delimited by residual membrane formations. In addition, the macroendocytosis process by endosome individualization is more important in soft fruits. In conclusion, the fruit texture depends on the extent of the links between cell wall polymers. Keywords: cherry, cell wall, texture, ultrastructural study.


1973 ◽  
Vol 51 (6) ◽  
pp. 1147-1153 ◽  
Author(s):  
James L. Harris ◽  
Willard A. Taber

The composition of the cell walls of synnemal and vegetative hyphae of Ceratocystis ulmi was studied by fractionation and assay of released compounds. Residues after enzymatic hydrolyses were examined by electron microscopy. The synnemal wall was found to have 67% carbohydrate, 4.52% amino sugar, 5.02% protein, 1.6% lipid, and 0.59% ash, which accounted for 78.7% of the cell wall. The vegetative hyphal wall contained 56% carbohydrate, 3.44% amino sugar, 7.92% protein, 4.5% lipid, and 1.45% ash, which totaled 73.3% of the wall weight. Sugars identified were D-glucose, D-mannose, D-galactose, and L-rhamnose. Enzymatic hydrolysis of both wall types by cellulase and laminaranase indicated the presence of beta-1,3 and beta-1,4 linkages of glucose polymers. N-acetylglucosamine was liberated by chitinase. Most of the 16 amino acids detected in each wall type were at least twice as abundant in vegetative hyphal walls as in synnemal hyphal walls. Cellulase and laminaranase treatment of cell walls revealed a fibrillar structure. Chitinase-treated walls did not appear as fibrous, suggesting that the fibrous structure may be mostly chitinous. Synnemal cell walls are covered by electron-dense granules which may correspond to the pigment in the synnemal hyphae.


2020 ◽  
Vol 10 (8) ◽  
pp. 2886 ◽  
Author(s):  
Maisa Mansour ◽  
Safa Abd Hamed ◽  
Mohamed Salem ◽  
Hayssam Ali

In the present study, Acacia saligna (Labill.) H.L.Wendl. wood blocks with dimensions of 0.5 × 1 × 2 cm were inoculated with five molds (Aspergillus niger, A. flavus, Alternaria tenuissima, Fusarium culmorum, and Trichoderma harzianum) and the changes in the organic acids (oxalic, citric, tartaric, succinic, glutaric, acetic, propionic, and butyric) of powdered wood were analyzed by HPLC. The effects of the five inoculated fungi on the alterations to the wood cell wall ultrastructures were examined by TEM. The wood became more acidic as it was inoculated with the studied fungi. From the HPLC analysis, the oxalic acid (293.34 µg/g o.d.) in the A. saligna, A. tenuissima (167.33 µg/g o.d.), and T. harzianum (245.01 µg/g o.d.) wood decreased, but it increased in the A. flavus (362.08 µg/g o.d.), A. niger (1202.53 µg/g o.d.), and F. culmorum (431.85 µg/g o.d.) inoculated wood. Citric acid was observed in the wood inoculated with A. flavus (110 µg/g o.d) and A. niger (2499.63 µg/g o.d). Tartaric (1150.98 µg/g o.d), acetic (2.04 µg/g o.d), and propionic (1.79 µg/g o.d) acids were found in the wood inoculated with A. niger. Butyric acid was found in small amounts. A loss of wood substances appeared as the electron-lucent increased in the middle lamella and the layers of the secondary wall. Within the secondary cell wall regions, checks and splits were also noted, which resulted from the effects of the acids on the carbohydrates, according to the fungus type and the acids. In conclusion, increasing the amount of organic acids in the wood samples through inoculation with fungi results in more degradations in the wood, especially in the wood inoculated with A. niger.


2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Alexis Eugene ◽  
Catherine Lapierre ◽  
John Ralph

Abstract Background Arabinoxylan in grass cell walls is acylated to varying extents by ferulate and p-coumarate at the 5-hydroxy position of arabinosyl residues branching off the xylan backbone. Some of these hydroxycinnamate units may then become involved in cell wall radical coupling reactions, resulting in ether and other linkages amongst themselves or to monolignols or oligolignols, thereby crosslinking arabinoxylan chains with each other and/or with lignin polymers. This crosslinking is assumed to increase the strength of the cell wall, and impedes the utilization of grass biomass in natural and industrial processes. A method for quantifying the degree of acylation in various grass tissues is, therefore, essential. We sought to reduce the incidence of hydroxycinnamate ester hydrolysis in our recently introduced method by utilizing more anhydrous conditions. Results The improved methanolysis method minimizes the undesirable ester-cleavage of arabinose from ferulate and p-coumarate esters, and from diferulate dehydrodimers, and produces more methanolysis vs. hydrolysis of xylan-arabinosides, improving the yields of the desired feruloylated and p-coumaroylated methyl arabinosides and their diferulate analogs. Free ferulate and p-coumarate produced by ester-cleavage were reduced by 78% and 68%, respectively, and 21% and 39% more feruloyl and p-coumaroyl methyl arabinosides were detected in the more anhydrous method. The new protocol resulted in an estimated 56% less combined diferulate isomers in which only one acylated arabinosyl unit remained, and 170% more combined diferulate isomers conjugated to two arabinosyl units. Conclusions Overall, the new protocol for mild acidolysis of grass cell walls is both recovering more ferulate- and p-coumarate-arabinose conjugates from the arabinoxylan and cleaving less of them down to free ferulic acid, p-coumaric acid, and dehydrodiferulates with just one arabinosyl ester. This cleaner method, especially when coupled with the orthogonal method for measuring monolignol hydroxycinnamate conjugates that have been incorporated into lignin, provides an enhanced tool to measure the extent of crosslinking in grass arabinoxylan chains, assisting in identification of useful grasses for biomass applications.


Holzforschung ◽  
2002 ◽  
Vol 56 (3) ◽  
pp. 225-228 ◽  
Author(s):  
E. J. M. Florence ◽  
R. Gnanaharan ◽  
P. Adya Singh ◽  
J. K. Sharma

Summary Botryodiplodia theobromae is the predominant fungus causing sapstain in rubberwood in Kerala, India. The fungus causes up to 12.2 percent weight loss in rubberwood over a period of sixteen weeks. Transmission Electron Microscopy (TEM) of sapstained rubberwood provided evidence on hyphal invasion of cells by B. theobromae through the pit region, facilitated by its ability to degrade pit membranes. The study also revealed that B. theobromae caused degradation of lignified cell walls by erosion of the cell wall surfaces of wood elements.


1967 ◽  
Vol 167 (1009) ◽  
pp. 443-445 ◽  

The elegant work that has been presented this afternoon has been concerned with the structure of lysozyme in relation to its action on model substrates of small molecular weight, or its inhibition by equally small molecules. The ‘natural’ substrate is presumably the mucopeptide of bacterial cell wall, which is a large, highly complex and insoluble molecule. A portion of a possible structure of a mucopeptide (Tipper & Strominger 1965) in this case from Staphylococcus aureus , is given in figure 51. Evidently in order to facilitate hydrolysis of the glycosidic links on C-1 of muramic acid (and, in the absence of O-acetyl groups, the enzyme is very good at this) lysozyme molecules must be able to approach closely to the relevant part of the polysaccharide backbone. One of the factors that appears to influence this approach of enzyme and substrate is the presence of positive charges on the mucopeptide. Isolated cell walls of Corynebacterium tritici were completely resistant to lysozyme, but could be made sensitive by the action of formamide at 150 °C for 15 min (Perkins 1965). It was found that this procedure did not remove more than 10% of the non-mucopeptide carbohydrate present, but it did formylate the free amino groups of diaminobutyric acid that occurred in the untreated wall. Acetylation by a mild procedure, followed by treatment with alkali to remove any O-acetyl groups, also caused the walls to become susceptible to dissolution by lysozyme.


Sign in / Sign up

Export Citation Format

Share Document