Degradative Effects of Guayule Resin on Natural Rubber

1981 ◽  
Vol 54 (1) ◽  
pp. 115-123 ◽  
Author(s):  
R. W. Keller ◽  
D. S. Winkler ◽  
H. L. Stephens
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Linoleic Acid ◽  
Natural Rubber ◽  
Unsaturated Fatty Acid ◽  
Unsaturated Fatty Acids ◽  
Oxidation Mechanism ◽  
Hydrocarbon Polymers ◽  
Rubber Degradation

Abstract This study indicates that the degradative effects of guayule resin on natural rubber are due to the presence of unsaturated fatty acids in the resin. Since linoleic acid is, by far, the most abundant unsaturated fatty acid in guayule resin, it appears that linoleic acid is primarily responsible for the degradative effects of guayule resin on natural rubber. A possible mechanism to explain the acceleration of natural rubber degradation caused by linoleic acid can be developed by fitting linoleic acid into the Bolland oxidation mechanism for hydrocarbon polymers.

AGGRAVATION OF CHOLESTEROL ATHEROSCLEROSIS IN RABBITS BY FREE UNSATURATED FATTY ACIDS

1959 ◽  
Vol 37 (3) ◽  
pp. 479-483 ◽  
Author(s):  
George Rona ◽  
Clifford I. Chappel ◽  
Roger Gaudry
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Linoleic Acid ◽  
Olive Oil ◽  
Unsaturated Fatty Acid ◽  
Unsaturated Fatty Acids

An unsaturated fatty acid preparation containing 90 to 95% linoleic acid was tested on cholesterol-induced hypercholesterolemia and atherosclerosis in the rabbit. The rabbits, treated with cholesterol dissolved in the unsaturated fatty acid, revealed a significantly higher hypercholesterolemia and more marked atherosclerosis than the rabbits that were treated with cholesterol dissolved in the same amount of olive oil.

AGGRAVATION OF CHOLESTEROL ATHEROSCLEROSIS IN RABBITS BY FREE UNSATURATED FATTY ACIDS

1959 ◽  
Vol 37 (1) ◽  
pp. 479-483 ◽  
Author(s):  
George Rona ◽  
Clifford I. Chappel ◽  
Roger Gaudry
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Linoleic Acid ◽  
Olive Oil ◽  
Unsaturated Fatty Acid ◽  
Unsaturated Fatty Acids

An unsaturated fatty acid preparation containing 90 to 95% linoleic acid was tested on cholesterol-induced hypercholesterolemia and atherosclerosis in the rabbit. The rabbits, treated with cholesterol dissolved in the unsaturated fatty acid, revealed a significantly higher hypercholesterolemia and more marked atherosclerosis than the rabbits that were treated with cholesterol dissolved in the same amount of olive oil.

scholarly journals Explore the gene network regulating the composition of fatty acids in cottonseed

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lihong Ma ◽  
Xinqi Cheng ◽  
Chuan Wang ◽  
Xinyu Zhang ◽  
Fei Xue ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Linoleic Acid ◽  
Linolenic Acid ◽  
Gene Network ◽  
Unsaturated Fatty Acids ◽  
Saturated Fatty Acids ◽  
Accumulation Pattern ◽  
Time Points ◽  
Expression Characteristics

Abstract Background Cottonseed is one of the major sources of vegetable oil. Analysis of the dynamic changes of fatty acid components and the genes regulating the composition of fatty acids of cottonseed oil is of great significance for understanding the biological processes underlying biosynthesis of fatty acids and for genetic improving the oil nutritional qualities. Results In this study, we investigated the dynamic relationship of 13 fatty acid components at 12 developmental time points of cottonseed (Gossypium hirsutum L.) and generated cottonseed transcriptome of the 12 time points. At 5–15 day post anthesis (DPA), the contents of polyunsaturated linolenic acid (C18:3n-3) and saturated stearic acid (C18:0) were higher, while linoleic acid (C18:2n-6) was mainly synthesized after 15 DPA. Using 5 DPA as a reference, 15,647 non-redundant differentially expressed genes were identified in 10–60 DPA cottonseed. Co-expression gene network analysis identified six modules containing 3275 genes significantly associated with middle-late seed developmental stages and enriched with genes related to the linoleic acid metabolic pathway and α-linolenic acid metabolism. Genes (Gh_D03G0588 and Gh_A02G1788) encoding stearoyl-ACP desaturase were identified as hub genes and significantly up-regulated at 25 DPA. They seemed to play a decisive role in determining the ratio of saturated fatty acids to unsaturated fatty acids. FAD2 genes (Gh_A13G1850 and Gh_D13G2238) were highly expressed at 25–50 DPA, eventually leading to the high content of C18:2n-6 in cottonseed. The content of C18:3n-3 was significantly decreased from 5 DPA (7.44%) to 25 DPA (0.11%) and correlated with the expression characteristics of Gh_A09G0848 and Gh_D09G0870. Conclusions These results contribute to our understanding on the relationship between the accumulation pattern of fatty acid components and the expression characteristics of key genes involved in fatty acid biosynthesis during the entire period of cottonseed development.

scholarly journals Fatty acid positional distribution (sn-2 fatty acids) and phospholipid composition in Chinese breast milk from colostrum to mature stage

2018 ◽  
Vol 121 (1) ◽  
pp. 65-73 ◽  
Author(s):  
Ke Wu ◽  
Runying Gao ◽  
Fang Tian ◽  
Yingyi Mao ◽  
Bei Wang ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Linoleic Acid ◽  
Fatty Acid Profile ◽  
Unsaturated Fatty Acids ◽  
Fatty Acid Content ◽  
Positional Distribution ◽  
Phospholipid Composition ◽  
Mature Stage ◽  
Feeding Time

AbstractThis study quantified the fatty acid profile with emphasis on the stereo-specifically numbered (sn) 2 positional distribution in TAG and the composition of main phospholipids at different lactation stages. Colostrum milk (n 70), transitional milk (n 96) and mature milk (n 82) were obtained longitudinally from healthy lactating women in Shanghai. During lactation, total fatty acid content increased, with SFA dominating in fatty acid profile. A high ratio of n-6:n-3 PUFA was observed as 11:1 over lactation due to the abundance of linoleic acid in Chinese human milk. As the main SFA, palmitic acid showed absolute sn-2 selectivity, while oleic acid, linoleic acid and α-linolenic acid, the main unsaturated fatty acids, were primarily esterified at the sn-1 and sn-3 positions. Nervonic acid and C22 PUFA including DHA were more enriched in colostrum with an sn-2 positional preference. A total of three dominant phospholipids (phosphatidylethanolamine (PE), phosphatidylcholine (PC) and sphingomyelin (SM)) were analysed in the collected samples, and each showed a decline in amount over lactation. PC was the dominant compound followed by SM and PE. With prolonged breast-feeding time, percentage of PE in total phospholipids remained constant, but PC decreased, and SM increased. Results from this study indicated a lipid profile different from Western reports and may aid the development of future infant formula more suitable for Chinese babies.

FATTY ACID COMPOSITION OF SERUM LIPIDS IN HYPER- AND HYPOTHYROIDISM

1972 ◽  
Vol 71 (1) ◽  
pp. 62-72 ◽  
Author(s):  
Knut Kirkeby
Keyword(s):  
Fatty Acids ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Linoleic Acid ◽  
Acid Composition ◽  
Serum Lipids ◽  
Unsaturated Fatty Acids ◽  
Eicosatrienoic Acid ◽  
High Linoleic Acid ◽  
Absolute Concentrations

ABSTRACT The fatty acid composition of cholesterol esters, phospholipids, and triglycerides of the serum has been studied in groups of hyperthyroid and hypothyroid women and also in control material matched for age. In hyperthyroidism, a decrease in the proportions of linoleic acid and an increase in the proportions of some saturated and mono-unsaturated fatty acids were observed. When absolute concentrations were considered, it appeared that the decrease in linoleic acid was almost equivalent to the entire decrease in total fatty acids in the serum of the hyperthyroid patients. In hypothyroidism no changes were noted in the proportions of linoleic, saturated and mono-unsaturated fatty acids, and the absolute concentrations reflected the general increase in serum lipids. It is believed that these findings may be explained by the changes in lipid turnover which are known to occur in disturbances of thyroid function. In hyperthyroidism, they lead to a linoleic acid deficiency, while a sparing effect must be operating in hypothyroidism. The finding of relatively high linoleic acid values combined with hyperlipaemia in hypothyroidism seems to be characteristic of the condition, since other types of hyperlipaemia are almost invariably combined with low percentages of linoleic acid. Results regarding arachidonic and eicosatrienoic acid are consistent with increased synthesis in hyperthyroidism, and decreased synthesis in hypothyroidism.

Enterotoxin B production by Staphylococcus aureus under controlled fatty acid nutrition induced by cerulenin

1977 ◽  
Vol 23 (9) ◽  
pp. 1145-1150 ◽  
Author(s):  
Robert A. Altenbern
Keyword(s):  
Fatty Acids ◽  
Staphylococcus Aureus ◽  
Fatty Acid ◽  
Membrane Fluidity ◽  
Unsaturated Fatty Acid ◽  
Unsaturated Fatty Acids ◽  
Basal Medium ◽  
Aureus Strain ◽  
Enterotoxin B ◽  
Fatty Acid Supplement

Cells of Staphylococcus aureus, strain S-6, can grow in the presence of 100 μg of cerulenin/ml if the basal medium is supplemented with certain saturated or unsaturated fatty acids. The production of enterotoxin B (SEB) is markedly influenced by both the ratio of saturated to unsaturated fatty acid and by the melting point of the unsaturated fatty acid supplement. The results presented suggest that a certain degree of membrane fluidity promotes maximum SEB production and that greater or lesser degrees of membrane fluidity prohibit substantial SEB formation but fail to affect final growth density.

scholarly journals DesT Coordinates the Expression of Anaerobic and Aerobic Pathways for Unsaturated Fatty Acid Biosynthesis in Pseudomonas aeruginosa

2009 ◽  
Vol 192 (1) ◽  
pp. 280-285 ◽  
Author(s):  
Chitra Subramanian ◽  
Charles O. Rock ◽  
Yong-Mei Zhang
Keyword(s):  
Fatty Acids ◽  
Pseudomonas Aeruginosa ◽  
Fatty Acid ◽  
Dna Sequences ◽  
Unsaturated Fatty Acid ◽  
Unsaturated Fatty Acids ◽  
Fatty Acid Biosynthesis ◽  
Acid Synthesis ◽  
Cell Extracts ◽  
Translational Start

ABSTRACT The fabA and fabB genes are responsible for anaerobic unsaturated fatty acid formation in Pseudomonas aeruginosa. Expression of the fabAB operon was repressed by exogenous unsaturated fatty acids, and DNA sequences upstream of the translational start site were used to affinity purify DesT. The single protein interaction with the fabAB promoter detected in wild-type cell extracts was absent in the desT deletion strain, as was the repression of fabAB expression by unsaturated fatty acids. Thus, DesT senses the overall composition of the acyl-coenzyme A pool to coordinate the expression of the operons for the anaerobic (fabAB) and aerobic (desCB) pathways for unsaturated fatty acid synthesis.

scholarly journals The biochemical content and antioxidant capacities of endemic Tanacetum densum (Lab.) Schultz Bip. subsp. laxum, and Tanacetum densum (Lab.) Schultz Bip. subsp. amani Heywood growing in Turkey

2021 ◽  
Vol 81 (4) ◽  
pp. 1106-1114
Author(s):  
İ. Emre
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Unsaturated Fatty Acid ◽  
Acid Content ◽  
Unsaturated Fatty Acids ◽  
Phenolic Content ◽  
Total Phenolics ◽  
Fatty Acid Content ◽  
Radical Scavenging ◽  
Unsaturated Fatty Acid Content

Abstract Medicinal plants have a significant role in preventing and curing several diseases, and Tanacetum L. is one of these plants. The aim of the present study is to determine the fatty acid, lipid-soluble vitamin, sterol, phenolic content, and antioxidant capacity of Tanacetum densum subsp. laxum and Tanacetum densum subsp. amani, to compare the effect of altitude on the biochemical content and to compare systematically by using fatty acids and phenolics. This study showed that palmitic acid (C16:0) and stearic acid (C18:0) are major sources of saturated fatty acid and oleic acid (C18:1 n9), and linoleic acid (18:2 n6c) and a-linolenic acid (C18:3 n3) are the principal unsaturated fatty acids in the two endemic Tanacetum densum taxa. Also, this study found that the unsaturated fatty acid content (60.11±1.61%) of Tanacetum densum subsp. laxum was higher than the unsaturated fatty acid content (44.13±1.28%) of Tanacetum densum subsp. amani. And also, the ω6/ω3 ratio of Tanacetum densum subsp. laxum (1.74) and Tanacetum densum subsp. amani (1.60) was found to be similar. However, this study determined that the lipid soluble vitamin and sterol content of two endemic Tanacetum taxa are low except for stigmasterol. Present study showed that catechin is principal phenolic in the Tanacetum densum taxa. This study also found that Tanacetum densum subsp. laxum and Tanacetum densum subsp. amani had the highest levels of catechin, vanillic acid, and caffeic acid content though the phenolic amounts, particularly catechin and quercetin, were dissimilar in the T. densum taxa. This study suggested that ecological conditions such as altitude may affect the biochemical content of two endemic Tanacetum densum taxa. Furthermore, the current study determined that two endemic Tanacetum L. taxa had potent radical scavenging capacities and found a correlation between total phenolics and antioxidant activity.

scholarly journals Quantitative Trait Loci and Candidate Genes Associated with Fatty Acid Content of Watermelon Seed

2014 ◽  
Vol 139 (4) ◽  
pp. 433-441 ◽  
Author(s):  
Geoffrey Meru ◽  
Cecilia McGregor
Keyword(s):  
Fatty Acids ◽  
Fatty Acid Composition ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Linoleic Acid ◽  
Palmitic Acid ◽  
Acid Composition ◽  
Seed Oil ◽  
Unsaturated Fatty Acids ◽  
Watermelon Seed

Seed oil percentage (SOP) and fatty acid composition of watermelon (Citrullus lanatus) seeds are important traits in Africa, the Middle East, and Asia where the seeds provide a significant source of nutrition and income. Oil yield from watermelon seed exceeds 50% (w/w) and is high in unsaturated fatty acids, a profile comparable to that of sunflower (Helianthus annuus) and soybean (Glycine max) oil. As a result of novel non-food uses of plant-derived oils, there is an increasing need for more sources of vegetable oil. To improve the nutritive value of watermelon seed and position watermelon as a potential oil crop, it is critical to understand the genetic factors associated with SOP and fatty acid composition. Although the fatty acid composition of watermelon seed is well documented, the underlying genetic basis has not yet been studied. Therefore, the current study aimed to elucidate the quality of watermelon seed oil and identify genomic regions and candidate genes associated with fatty acid composition. Seed from an F2 population developed from a cross between an egusi type (PI 560023), known for its high SOP, and Strain II (PI 279261) was phenotyped for palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1), and linoleic acid (18:2). Significant (P < 0.05) correlations were found between palmitic and oleic acid (0.24), palmitic and linoleic acid (–0.37), stearic and linoleic acid (–0.21), and oleic and linoleic acid (–0.92). A total of eight quantitative trait loci (QTL) were associated with fatty acid composition with a QTL for oleic and linoleic acid colocalizing on chromosome (Chr) 6. Eighty genes involved in fatty biosynthesis including those modulating the ratio of saturated and unsaturated fatty acids were identified from the functionally annotated genes on the watermelon draft genome. Several fatty acid biosynthesis genes were found within and in close proximity to the QTL identified in this study. A gene (Cla013264) homolog to fatty acid elongase (FAE) was found within the 1.5-likelihood-odds (LOD) interval of the QTL for palmitic acid (R2 = 7.6%) on Chr 2, whereas Cla008157, a homolog to omega-3-fatty acid desaturase and Cla008263, a homolog to FAE, were identified within the 1.5-LOD interval of the QTL for palmitic acid (R2 = 24.7%) on Chr 3. In addition, the QTL for palmitic acid on Chr 3 was located ≈0.60 Mbp from Cla002633, a gene homolog to fatty acyl- [acyl carrier protein (ACP)] thioesterase B. A gene (Cla009335) homolog to ACP was found within the flanking markers of the QTL for oleic acid (R2 = 17.9%) and linoleic acid (R2 = 21.5%) on Chr 6, whereas Cla010780, a gene homolog to acyl-ACP desaturase was located within the QTL for stearic acid (R2 = 10.2%) on Chr 7. On Chr 8, another gene (Cla013862) homolog to acyl-ACP desaturase was found within the 1.5-LOD interval of the QTL for oleic acid (R2 = 13.5%). The genes identified in this study are possible candidates for the development of functional markers for application in marker-assisted selection for fatty acid composition in watermelon seed. To the best of our knowledge, this is the first study that aimed to elucidate genetic control of the fatty acid composition of watermelon seed.

Sign in / Sign up

Export Citation Format

Share Document