Aldosine, an Acid Hydrolysis Product from the Aldol Cross-link of Bovine Elastin and Collagen

Human aortic elastin reduced with [3H]borohydride was analysed by ion-exchange chromatography after alkali or acid hydrolysis. Alkali hydrolysates of elastins contained a radioactive peak that was eluted between proline and leucine. This peak was not present in foetal elastin, but its proportion increased steadily during aging. Aortic samples from patients with annulo-aortic ectasia (aneurysm of the ascending aorta), including one with classical Marfan syndrome, contained less elastin (CNBr-insoluble material) than did the age-matched controls. The proportion of radioactivity in the new peak of all these aortas was low when compared with age-matched controls. Gas-chromatographic/mass-spectrometric analysis suggested that it contained a cyclic derivative of a hydrated aldol-condensation product. The concentration of the cross-link precursors, lysine aldehyde and aldol-condensation product (estimated from the acid-hydrolysis product 6-chloronorleucine and the acid-degradation product of reduced aldol-condensation product) was high in very young aortas but remained quite stable after childhood. No differences were observed in cross-link profiles of acid hydrolysates between pathological and control aortas. A low proportion of radioactivity in the new peak may indicate the presence of young or immature elastin in the pathological aortas.

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Structure Elucidation of 2-Amino-5-phenyl-2-oxazolin-4-one (Pemoline) and X-Ray Structure of its Hydrolysis Product 5-Phenyl-oxazolidine-2,4- dione

Zeitschrift für Naturforschung B ◽

10.1515/znb-2005-0806 ◽

2005 ◽

Vol 60 (8) ◽

pp. 853-857 ◽

Cited By ~ 3

Author(s):

Piotr Kuś ◽

Peter G. Jones ◽

Rafał Celiński

Keyword(s):

Acetic Acid ◽

Hydrogen Bonds ◽

Acid Hydrolysis ◽

Single Crystals ◽

Structure Elucidation ◽

Hydrolysis Product ◽

Spectroscopic Properties ◽

Aqueous Acetic Acid ◽

X Ray ◽

Independent Molecules

In this study we compare spectroscopic properties of pemoline (2-amino-5-phenyl-2-oxazolin- 4-one) and its acid hydrolysis product 5-phenyl-oxazolidine-2,4-dione. Crystallization of pemoline from aqueous acetic acid gave single crystals of compound 2, the structure of which was determined by X-ray studies. All four crystallographically independent molecules form dimers linked by N-H···O = C hydrogen bonds.

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The Effects of Microwave-Assisted Pretreatment and Cofermentation on Bioethanol Production from Elephant Grass

International Journal of Microbiology ◽

10.1155/2020/6562730 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11

Author(s):

Sefrinus Maria Dolfi Kolo ◽

Deana Wahyuningrum ◽

Rukman Hertadi

Keyword(s):

Acid Hydrolysis ◽

Hydrolysis Product ◽

Pichia Stipitis ◽

Pennisetum Purpureum ◽

Bioethanol Production ◽

Elephant Grass ◽

Microwave Assisted ◽

Liquid Chromatographic Analysis ◽

High Concentrations ◽

Liquid Chromatographic

The process of acid hydrolysis using conventional methods at high concentrations results in products having lower yields, and it needs a longer time of process; therefore, it becomes less effective. In this study, we analyzed the effects of microwave-assisted pretreatment and cofermentation on bioethanol production from elephant grass (Pennisetum purpureum). We used a combination of delignification techniques and acid hydrolysis by employing a microwave-assisted pretreatment method on elephant grass (Pennisetum purpureum) as a lignocellulosic material. This was followed by cofermentation with Saccharomyces cerevisiae ITB-R89 and Pichia stipitis ITB-R58 to produce bioethanol. The optimal sugar mixtures (fructose and xylose) of the hydrolysis product were subsequently converted into bioethanol by cofermentation with S. cerevisiae ITB-R89 and P. stipitis ITB-R58, carried out with varying concentrations of inoculum for 5 days (48 h) at 30°C and pH 4.5. The high-power liquid chromatographic analysis revealed that the optimal inoculum concentration capable of converting 76.15% of the sugar mixture substrate (glucose and xylose) to 10.79 g/L (34.74% yield) of bioethanol was 10% (v/v). The optimal rate of ethanol production was 0.45 g/L/d, corresponding to a fermentation efficiency of 69.48%.

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Characterization of an acid hydrolysis product of starfish toxins as a 5.alpha.-pregnane derivative

Journal of the American Chemical Society ◽

10.1021/ja00766a087 ◽

1972 ◽

Vol 94 (11) ◽

pp. 4051-4052 ◽

Cited By ~ 25

Author(s):

Yuzuru Shimizu

Keyword(s):

Acid Hydrolysis ◽

Hydrolysis Product

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Structural studies on cross-linked peptides containing lysinonorleucine from elastin of porcine aorta

Canadian Journal of Biochemistry ◽

10.1139/o77-034 ◽

1977 ◽

Vol 55 (3) ◽

pp. 244-248

Author(s):

Maonique Davril ◽

Kia-Ki Han

Keyword(s):

Acid Hydrolysis ◽

Structural Studies ◽

Cross Link ◽

Structural Investigations ◽

Partial Acid Hydrolysis

Three lysinonorleucine peptides were isolated from mature porcine aorta elastin after enzymic digestions and partial acid hydrolysis. The structural investigations which were performed suggest that different regions containing lysinonorleucine may exist. The role of this cross-link in mature elastin is discussed.

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4-O-METHYL-D-GLUCURONIC ACID AND 4-O-METHYL-D-GLUCOSE

Canadian Journal of Chemistry ◽

10.1139/v57-086 ◽

1957 ◽

Vol 35 (7) ◽

pp. 595-598 ◽

Cited By ~ 9

Author(s):

P. A. J. Gorin

Keyword(s):

Acid Hydrolysis ◽

Good Yield ◽

Glucuronic Acid ◽

Hydrolysis Product ◽

Novel Method

A novel method for the preparation of 4-O-methyl-D-glucuronic acid is described. This sugar and 4-O-methyl-D-glucose were obtained in good yield by two different series of reactions from 2-O-(4-O-methyl-D-glucopyranuronosido)-D-xylose, an acid hydrolysis product of the hemicellulose of Populustacamahacca Mill.

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