Arabitol

About: Arabitol is a research topic. Over the lifetime, 388 publications have been published within this topic receiving 8398 citations. The topic is also known as: D-(+)-Arabitol & D-arabitol.

Carbohydrate Composition and Acid Invertase Activity in Rice Leaves Infected with Pyricularia oryzae

Abstract: Ethanol-soluble carbohydrates in healthy and blast-infected leaves and also cultures of Pyricularia oryzae were analyzed using gas chromatography Arabitol, mannitol, and trehalose occurred in infected leaf tissue, but not in healthy controls Cultures of P oryzae contained mannitol and trehalose, but not arabitol and sucrose The presence of arabitol only in blast-infected rice leaves suggests that arabitol synthesis may be induced in infected leaf tissue as a result of the rice-blast fungus interaction, but may not be within blast fungus itself The amounts of glucose, fructose, and sucrose in infected leaves were slightly increased until 5 days, and greatly enhanced at 7 days after inoculation, There were no differences in amounts of these sugars between the cultivars Nakdong and Dobong At 7 days after inoculation, increases in amounts of arabitol, mannitol, and trehalose were pronounced in the susceptible cultivar Nakdong than in the moderately susceptible cultivar Dobong The increased amounts of glucose and fructose in infected plants of the two cultivars were closely correlated with the presence of a very active invertase Zusammenfassung Athanollosliche Kohlenhydrate in gesunden und mit Reisbraune infizierten Blattern und auch in Pyricularia oryzae-Kulturen wurden gaschromatographisch analysiert Arabitol, Mannitol und Trehalose waren im infizierten Blattgewebe vorhanden, aber nicht im gesunden Cewebe P oryzae-Kulturen enthielten Mannitol und Trehalose, aber kein Arabitol und Saccharose Das Vorhandensein von Arabitol nur in durch Reisbraune infizierten Blattern ist ein Hinweis dafur, das die Arabitolsynthese im infizierten Blattgewebe durch die Wechselwirkung zwischen Reis und P oryzae induziert sein kann, aber nicht innerhalb von P oryzae selbst Die Gehalte der Glukose, Fruktose und Saccharose in den infizierten Blattern waren bis funf Tage nach der Infektion etwas, aber am siebten Tage stark erhoht Die Niveaus dieses Zuckers waren zwischen den Sorten Nakdong und Dobong nicht unterschiedlich Am siebten Tage nach der Infektion waren die Zunahme von Arabitol, Mannitol und Trehalose in der anfalligen Sorte Nakdong mehr ausgepragt als in der mittelmasig anfalligen Sorte Dobong Die zunehmenden Gehalte von Glukose und Fruktose in den infizierten Pflanzen der zwei Sorten korrelierten stark mit den Invertaseaktivitatniveaus

Evaluation of Product Distribution in Chemostat and Batch Fermentation in Lactic Acid-Producing Komagataella phaffii Strains Utilizing Glycerol as Substrate.

Abstract: Lactic acid is the monomeric unit of polylactide (PLA), a bioplastic widely used in the packaging, automotive, food, and pharmaceutical industries. Previously, the yeast Komagataella phaffii was genetically modified for the production of lactate from glycerol. For this, the bovine L-lactate dehydrogenase- (LDH)-encoding gene was inserted and the gene encoding the pyruvate decarboxylase (PDC) was disrupted, resulting in the GLp strain. This showed a yield of 67% L-lactic acid and 20% arabitol as a by-product in batches with oxygen limitation. Following up on these results, the present work endeavored to perform a detailed study of the metabolism of this yeast, as well as perturbing arabitol synthesis in an attempt to increase lactic acid titers. The GLp strain was cultivated in a glycerol-limited chemostat at different dilution rates, confirming that the production of both lactic acid and arabitol is dependent on the specific growth rate (and consequently on the concentration of the limiting carbon source) as well as on the oxygen level. Moreover, disruption of the gene encoding arabitol dehydrogenase (ArDH) was carried out, resulting in an increase of 20% in lactic acid and a 50% reduction in arabitol. This study clarifies the underlying metabolic reasons for arabitol formation in K. phaffii and points to ways for improving production of lactic acid using K. phaffii as a biocatalyst.

Bioformation of Volatile and Nonvolatile Metabolites by Saccharomycopsis fibuligera KJJ81 Cultivated under Different Conditions—Carbon Sources and Cultivation Times

Abstract: Saccharomycopsis fibuligera KJJ81 isolated from nuruk is an amylolytic yeast that is widely used as a microbial starter in various fermented foods. Volatile and nonvolatile metabolites of S. fibuligera KJJ81 were investigated according to different carbon sources and cultivation times using a nontargeted metabolomic approach. Partial-least-squares discriminant analysis was applied to determine the major metabolites, which were found to be closely related to the clustering and discrimination of S. fibuligera KJJ81 samples. Some volatile metabolites derived from phenylalanine, such as 2-phenylethanol, 2-phenylethyl acetate, and ethyl phenylacetate, were predominantly found in cultivation medium containing glucose (YPD medium). In addition, the level of 2-phenylethanol increased continuously with the cultivation time. In terms of nonvolatile metabolites, carbohydrates (mannose, arabitol, and mannitol), fatty acids (palmitic acid and stearic acid), organic acids (oxalic acid and succinic acid), and amino acids (isoleucine, serine, alanine, glutamic acid, glycine, proline, phenylalanine, and threonine) were the main contributors to S. fibuligera KJJ81 samples cultivated in YPD medium according to cultivation time. These results show that the formation of volatile and nonvolatile metabolites of S. fibuligera KJJ81 can be significantly affected by both the carbon sources and the cultivation time.

Efficient desymmetrization of "pseudo"-C2-symmetric substrates: illustration in the synthesis of a disubstituted butenolide from arabitol.

Abstract: A short synthesis of the homochiral disubstituted butenolide 1 is described in four steps from arabitol. The key steps are the selective kinetic protection of arabitol and the cyclization of 11 to form the butenolide ring. This last transformation represents a rare example of a fully stereoselective cyclitive desymmetrization process of a “pseudo”-C2-symmetric substrate.