Studies on Sporopollenin Biosynthesis in Cucurbita maxima I: The Substantial Labeling of Sporopollenin from Cucurbita maxima after Application of [14C]Phenylalanine

1993 ◽  
Vol 48 (1-2) ◽  
pp. 10-15 ◽  
Author(s):  
Sabine Gubatz ◽  
Rolf Wiermann
Keyword(s):  
Terephthalic Acid ◽  
Phthalic Acid ◽  
Degradation Products ◽  
Hydroxybenzoic Acid ◽  
Cucurbita Maxima ◽  
Purification Step ◽  
Decanedioic Acid ◽  
Octanedioic Acid ◽  
High Level ◽  
Tracer Experiments

The results of tracer experiments performed with anthers of Tulipa cv. Apeldoorn have already shown that a high level of incorporation into the sporopollenin fraction was achieved, when [14C]phenylalanine was applicated as a precursor. In order to investigate whether the substantial incorporation of [14C]phenylalanine is a unique phenomenon restricted to Tulipa, tracer experiments were carried out on anthers of Cucurbita maxima. The sporopollenin fraction was isolated and purified by a gentle method including extractions with various solvents, incubations with hydrolysing enzymes and fractionated saponifications. The remaining, as well as the released radioactivity, was determined after each purification step. After the application of [U-14C]phenylalanine, a substantial incorporation into the sporopollenin fraction was determined. The values were clearly higher than those obtained with [1-14C]glucose or those from corresponding experiments on Tulipa anthers. After potash fusion of sporopollenin fractions labeled via [U-14C]phenylalanine, p-hydroxybenzoic acid was shown to be the main com ponent among the ether soluble acids; moreover it showed the highest level of radioactivity. No radioactivity was detected in the degradation products oxalic acid, benzoic acid, phthalic acid and terephthalic acid or octanedioic acid- and decanedioic acid-dimethylester.

Studies on hydrolysis and radiolysis of N,N,N′,N′-tetraoctyl-3-oxapentane-1,5-diamide

2002 ◽  
Vol 90 (3) ◽  
Author(s):  
Y. Sugo ◽  
Y. Sasaki ◽  
S. Tachimori
Keyword(s):  
Gamma Irradiation ◽  
Room Temperature ◽  
Degradation Products ◽  
Liquid Waste ◽  
Amide Bond ◽  
Radioactive Liquid Waste ◽  
Ether Bond ◽  
Nuclear Fuel Reprocessing ◽  
High Level ◽  
Fuel Reprocessing

SummaryHydrolytic and radiolytic stabilities of a promising extractant, N,N,N′,N′-tetraoctyl-3-oxapentane-1,5-diamide (TODGA), for actinides in high-level radioactive liquid waste from nuclear fuel reprocessing were investigated in air at room temperature. Hydrolysis by nitric acid was not observed, whereas radiolysis by gamma irradiation was notably observed. The radiolysis study showed that an amide-bond, an ether-bond, and a bond adjacent to the ether-bond tended to be broken by gamma irradiation, and dioctylamine and various N,N-dioctylmonoamides were identified as the main degradation products by GC/MS and NMR analyses. The

scholarly journals Historic records of organic aerosols from a high Alpine glacier: implications of biomass burning, anthropogenic emissions, and dust transport

2015 ◽  
Vol 15 (9) ◽  
pp. 13747-13781 ◽  
Author(s):  
C. Müller-Tautges ◽  
A. Eichler ◽  
M. Schwikowski ◽  
G. B. Pezzatti ◽  
M. Conedera ◽  
...  
Keyword(s):  
Organic Compounds ◽  
Phthalic Acid ◽  
Ice Core ◽  
Dicarboxylic Acids ◽  
Anthropogenic Emissions ◽  
Hydroxybenzoic Acid ◽  
Dust Transport ◽  
Historic Records ◽  
Highly Correlated ◽  
Pinic Acid

Abstract. Historic records of α-dicarbonyls (glyoxal, methylglyoxal), carboxylic acids (C6–C12 dicarboxylic acids, pinic acid, p-hydroxybenzoic acid, phthalic acid, 4-methylphthalic acid), and major ions (oxalate, formate, calcium) were determined with annual resolution in an ice core from Grenzgletscher in the southern Swiss Alps, covering the time period from 1942 to 1993. Measurements were conducted using ultra-high performance liquid chromatography (UHPLC) coupled to electrospray ionization high resolution mass spectrometry (ESI-HRMS). For the first time, long-term records of the carboxylic acids and dicarbonyls as well as their source apportionment are reported for Western Europe. Source assignment of the organic species present in the ice core was performed using principal component analysis. Our results suggest biomass burning, anthropogenic emissions, and transport of mineral dust to be the main parameters influencing the concentration of organic compounds. Ice core records of several highly correlated compounds (e.g. p-hydroxybenzoic acid, pinic acid, C7 and C8 dicarboxylic acids) can be related to the forest fire history in southern Switzerland. P-hydroxybenzoic acid was found to be the best organic fire tracer in the study area, revealing the highest correlation with the burned area from fires. Historical records of methylglyoxal, phthalic acid, and dicarboxylic acids C6, C10, and C12 are comparable with that of anthropogenic emissions of volatile organic compounds (VOCs). The small organic acids oxalic acid and formic acid are both highly correlated with calcium, suggesting their records to be affected by changing mineral dust transport to the drilling site.

scholarly journals Some Decomposition Routes in the Mass Spectra of Aromatic Carboxylic Acids

1965 ◽  
Vol 20 (7) ◽  
pp. 883-887 ◽  
Author(s):  
J. H. Beynon ◽  
B. E. Job ◽  
A. E. Williams
Keyword(s):  
Carboxylic Acid ◽  
Benzoic Acid ◽  
Terephthalic Acid ◽  
Phthalic Acid ◽  
Mass Spectra ◽  
Deuterium Atom ◽  
Acid Group ◽  
Isophthalic Acid ◽  
Carboxylic Acid Group ◽  
Hydrogen Atoms

The mass spectra of benzoic acid, phthalic acid, isophthalic acid and terephthalic acid, together with the analogues deuterated on the carboxylic acid group have been studied. Exchange of the deuterium atom with hydrogen atoms on the positions ortho to a carboxylic acid group on the aromatic ring has been studied using meta-stable peaks.

Biodegradation of DBP by Biofilm Reactor

2012 ◽  
Vol 178-181 ◽  
pp. 390-399 ◽  
Author(s):  
Jian Yu ◽  
Yu Fu ◽  
Ming Jie Jiang ◽  
Wen Hui Ren
Keyword(s):  
Kinetic Model ◽  
Removal Efficiency ◽  
Phthalic Acid ◽  
Dibutyl Phthalate ◽  
Hydraulic Retention Time ◽  
Degradation Products ◽  
Biofilm Reactor ◽  
Metabolic Intermediate ◽  
Environmental Hormone ◽  
Positive Effect

The removal efficiency of dibutyl phthalate (DBP) and its environmental hormone treated by biofilm reactor has been investigated. Besides, the the kinetic model of the degradation of DBP and its degradation products in the reactor have been discussed. The results indicate that the biofilm reactor had a positive effect on the removal of DBP and was able to significantly reduce the environmental hormone in DBP influent. The activity of β-galactosidase dropped from 13.55 millers to 3.3 millers and the removal efficiency of DBP reached 98.5% at water temperature 20°C and HRT (Hydraulic Retention Time) of 4 hours. The metabolic intermediate of DBP in the reactor mainly consisted of dibutyl phthalate and phthalic acid. The kinetic models of the degradation of DBP can be expressed by Lawrence-McCarty equation.

The balance between alkali diffusion and alkali consuming reactions during impregnation of softwood. Impregnation for kraft pulping revisited

Holzforschung ◽  
2018 ◽  
Vol 72 (3) ◽  
pp. 169-178 ◽  
Author(s):  
Elisabet Brännvall ◽  
Anders Reimann
Keyword(s):  
Degradation Products ◽  
Kraft Pulping ◽  
Alkali Concentration ◽  
Yield Losses ◽  
Degradation Reactions ◽  
Carbohydrate Degradation ◽  
Alkali Consumption ◽  
High Level ◽  
Short Time ◽  
Time Lead

AbstractThe purpose of the impregnation stage is to ensure that cooking chemicals reach all parts of the chips. However, as alkali comes into contact with wood, reactions take place, which alter the paths available for ionic transport and dissolve wood components. The aim of the present study is to establish the most favorable impregnation conditions, which result in an even alkali concentration profile through the chip at a sufficiently high level without extensive yield losses due to peeling. Softwood chips were subjected to different impregnation conditions. The progress of impregnation was assessed by analyzing the concentration of hydroxide ions in the bound liquor inside wood chips and the release of acetic acid. The extent of undesired reactions was measured as the amount of carbohydrate degradation products formed and amount of wood dissolved. Increased temperature and time lead to more degradation of the carbohydrates during impregnation. At high temperature, the concentration of alkali in the bound liquor was lower due to higher alkali consumption in degradation reactions. The most favorable process is to perform impregnation at an elevated initial effective alkali (EA) for a short time. This resulted in an increased alkali concentration in the bound liquor within the chip without extensive carbohydrate degradation.

scholarly journals Fluorescent Sensors For Hg2+ and Cu2+ Based On Condensation Products of 4H-1,2,4 Triazole-4-Amine And Carboxylated Benzoic Acids

2021 ◽  
Author(s):  
Satyapriya Deka ◽  
Ankur K Guha ◽  
Diganta Kumar Das
Keyword(s):  
Benzoic Acid ◽  
Terephthalic Acid ◽  
Phthalic Acid ◽  
Copper Ion ◽  
Binding Constants ◽  
Isophthalic Acid ◽  
Benzoic Acids ◽  
Health Issues ◽  
Derivatives Of ◽  
Optimized Geometries

Abstract Mercury (Hg) causes serious health issues in its all forms. Deficiency as well as excess of copper ion (Cu2+) in human body is hazardous. A series of four compounds have been derived from carboxylated benzoic acids (benzoic acid, isophthalic acid, terephthalic acid and phthalic acid) and 4H-1,2,4 triazole-4-amine and characterized. Fluorescencce detection of Hg2+ was recorded by the derivates with benzoic acid and isophthalic acid while the derivatives of terephthalic acid and phthalic acid detect Cu2+ by fluorescence “off” mode. Metal ions like Li+, Na+, K+, Zn2+, Al3+, Mg2+, Mn2+, Co2+, Ni2+, Cu2+, Cd2+, Pb2+ and Hg2+ found not to interfere. The stoichiometry of binding is 1:1 for the benzoic acid derivative with Hg2+ while it is 1:2 for the other three derivatives. The binding constants are ca. 10− 4.5 between the sensors and Hg2+ or Cu2+ and detection limits are around 10− 5.5 M. DFT calculation provided optimized geometries of the sensors and confirmed the stoichiometry of binding with Hg2+/Cu2+.

scholarly journals Generation and Starch Characterization of Non-Transgenic BEI and BEIIb Double Mutant Rice (Oryza sativa) with Ultra-high Level of Resistant Starch

2020 ◽  
Author(s):  
Satoko Miura ◽  
Nana Koyama ◽  
Naoko Crofts ◽  
Yuko Hosaka ◽  
Misato Abe ◽  
...  
Keyword(s):  
Oryza Sativa ◽  
Resistant Starch ◽  
Double Mutant ◽  
Degradation Products ◽  
Amylose Content ◽  
Gel Filtration ◽  
Rice Flour ◽  
Rice Cultivar ◽  
Number Of Patients ◽  
High Level

Abstract Background Cereals high in resistant starch (RS) are gaining popularity, as their intake is thought to help manage diabetes and prediabetes. Number of patients suffering from diabetes is also increasing in Asian countries where people consume rice as a staple food, hence generation of practically growable high RS rice line has been anticipated. It is known that suppression of starch branching enzyme (BE) IIb increases RS content in cereals. To further increase RS content and for more practical use, we generated a non-transgenic be1 be2b double mutant rice (Oryza sativa) line, which completely lacked both proteins, by crossing a be1 mutant with a be2b mutant. Results The be1 be2b mutant showed a decrease in intermediate amylopectin chains and an increase in long amylopectin chains compared with be2b. The amylose content of be1 be2b mutant (51.7%) was the highest among all pre-existing non-transgenic rice lines. To understand the effects of chewing steamed rice and cooking rice flour on RS content, RS content of mashed and un-mashed steamed rice as well as raw and gelatinized rice flour were measured using be1 be2b and its parent mutant lines. The RS contents of mashed steamed rice and raw rice flour of be1 be2b mutant (28.4% and 35.1%, respectively) were 3-fold higher than those of be2b mutant. Gel-filtration analyses of starch treated with digestive enzymes showed that the RS in be1 be2b mutant was composed of the degradation products of amylose and long amylopectin chains. Seed weight of be1 be2b mutant was approximately 60% of the wild type and rather heavier than that of be2b mutant. Conclusions The endosperm starch in be1 be2b double mutant rice were enriched with long amylopectin chains. This led to a great increase in RS content in steamed rice grains and rice flour in be1 be2b compared with be2b single mutant. be1 be2b generated in this study must serve as a good material for an ultra-high RS rice cultivar.

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