scholarly journals Conversion of higher fatty acids or higher fatty acid esters to long-chain alkanes by acid added metal catalyst under mild hydrothermal conditions

2022 ◽  
Vol 156 ◽  
pp. 106328
Author(s):  
Xin Cai ◽  
Zhaoxia Zhang ◽  
Yueyuan Ye ◽  
Duo Wang ◽  
Shuirong Li ◽  
...  
1968 ◽  
Vol 23 (5) ◽  
pp. 733-735 ◽  
Author(s):  
Kurt Egger

The fatty acid esters of Xanthophylls in the flowers of Helianthus annuus L. have been investigated. The pigments taraxanthin = luteinepoxid, lutein, violaxanthin and kryptoxanthin are combined with the saturated fatty acids C18 (stearic-), C16 (palmitic-), C14 (myristic-), C12 (lauric-) and acetic acid. Acetic acid derivatives seldom occur in the field of carotenoids: fucoxanthin and vaucheriaxanthin7 are the only examples. The acetylation prefers the 3-OH of lutein and the hydroxyls near the epoxygroups. The long chain fatty acids are mainly found in the allylic position. No detectable amounts of furanoidic epoxides are present.


1992 ◽  
Vol 70 (6) ◽  
pp. 448-454 ◽  
Author(s):  
Ewa Świeżewska ◽  
T. Chojnacki ◽  
W. J. Jankowski ◽  
K. Singh ◽  
J. Olsson

The long chain polyprenols composed of 30 and more isoprene units from leaves of plants belonging to the genera Potentilla and Rosa have been described. They occur in the form of fatty acid esters. The composition of polyprenol mixture was species dependent and its content reached ca. 0.5% wet weight. Large scale preparation of individual polyprenols from a natural polyprenol mixture was performed using time-extended liquid chromatography on the hydrophobic gel Lipidex-5000.Key words: long chain polyprenols, Rosaceae.


2021 ◽  
Vol 8 ◽  
Author(s):  
Teresa Kellerer ◽  
Karin Kleigrewe ◽  
Beate Brandl ◽  
Thomas Hofmann ◽  
Hans Hauner ◽  
...  

Background: Fatty acid esters of hydroxy fatty acids (FAHFAs) are a group of fatty acids with potential anti-inflammatory and anti-diabetic effects. The blood levels of FAHFAs and their regulation in humans have hardly been studied.Objective: We aimed to investigate serum FAHFA levels in well-characterized human cohorts, to evaluate associations with age, sex, BMI, weight loss, diabetic status, and diet.Methods: We analyzed levels of stearic-acid-9-hydroxy-stearic-acid (9-SAHSA), oleic-acid-9-hydroxy-stearic-acid (9-OAHSA) and palmitic-acid-9-hydroxy-palmitic-acid (9-PAHPA) as well as different palmitic acid-hydroxy-stearic-acids (PAHSAs) by HPLC-MS/MS with the use of an internal standard in various cohorts: A cohort of different age groups (18–25y; 40–65y; 75–85y; Σn = 60); severely obese patients undergoing bariatric surgery and non-obese controls (Σn = 36); obese patients with and without diabetes (Σn = 20); vegetarians/vegans (n = 10) and omnivores (n = 9); and young men before and after acute overfeeding with saturated fatty acids (SFA) (n = 15).Results: Omnivores had substantially higher FAHFA levels than vegetarians/vegans [median (25th percentile; 75th percentile) tFAHFAs = 12.82 (7.57; 14.86) vs. 5.86 (5.10; 6.71) nmol/L; P < 0.05]. Dietary overfeeding by supplementation of SFAs caused a significant increase within 1 week [median tFAHFAs = 4.31 (3.31; 5.27) vs. 6.96 (6.50; 7.76) nmol/L; P < 0.001]. Moreover, obese patients had lower FAHFA levels than non-obese controls [median tFAHFAs = 3.24 (2.80; 4.30) vs. 5.22 (4.18; 7.46) nmol/L; P < 0.01] and surgery-induced weight loss increased 9-OAHSA level while other FAHFAs were not affected. Furthermore, significant differences in some FAHFA levels were found between adolescents and adults or elderly, while no differences between sexes and between diabetic and non-diabetic individuals were detected.Conclusions: FAHFA serum levels are strongly affected by high SFA intake and reduced in severe obesity. Age also may influence FAHFA levels, whereas there was no detectable relation with sex and diabetic status. The physiological role of FAHFAs in humans remains to be better elucidated.Trial Registration: All studies referring to these analyses were registered in the German Clinical Trial Register (https://www.drks.de/drks_web/) with the numbers DRKS00009008, DRKS00010133, DRKS00006211, and DRKS00009797.


2018 ◽  
Vol 458 ◽  
pp. 67-72 ◽  
Author(s):  
Magdalena Hümmer ◽  
Selin Kara ◽  
Andreas Liese ◽  
Ina Huth ◽  
Jens Schrader ◽  
...  

2016 ◽  
Vol 78 (5-6) ◽  
Author(s):  
Mohd Basyaruddin Abdul Rahman ◽  
Siti Salhah Othman ◽  
Noor Mona Md Yunus

The enzymatic selectivity of Lipase from Candida rugosa immobilized onto a calcined layered double hydroxide (CLDHs-CRL) towards the chain-length of fatty acids and alcohols in the synthesis of fatty acid esters was investigated.  The results showed that CMAN-CRL catalyzed the esterification process with fatty acids of medium chain lengths (C10-C14) effectively while, CNAN-CRL and CZAN-CRL exhibited high percentage conversion in fatty acids with carbon chain lengths of C8-C12 and C10-C18, respectively. In the alcohol selectivity study, CMAN-CRL showed high selectivity toward alcohols with carbon chain lengths of C4, C6 and C10.  On the other hand, both CNAN-CRL and CZAN-CRL exhibited rather low selectivity towards longer carbon chain length of alcohols. 


Cosmetics ◽  
2019 ◽  
Vol 6 (3) ◽  
pp. 45 ◽  
Author(s):  
Dorota Dobler ◽  
Thomas Schmidts ◽  
Sören Wildenhain ◽  
Ilona Seewald ◽  
Michael Merzhäuser ◽  
...  

Human skin is a complex ecosystem and is host to a large number of microorganisms. When the bacterial ecosystem is balanced and differentiated, skin remains healthy. However, the use of cosmetics can change this balance and promote the appearance of skin diseases. The skin’s microorganisms can utilize some cosmetic components, which either promote their growth, or produce metabolites that influence the skin environment. In this study, we tested the ability of the Malassezia species and some bacterial strains to assimilate substances frequently used in dermal formulations. The growth capability of microorganisms was determined and their lipase activity was analyzed. The growth of all Malassezia spp. in the presence of free acids, free acid esters, and fatty alcohols with a fatty chain length above 12 carbon atoms was observed. No growth was observed in the presence of fatty alcohol ethers, secondary fatty alcohols, paraffin- and silicon-based substances, polymers, polyethylene glycols, quaternary ammonium salts, hydroxy fatty acid esters, or fatty acids and fatty acid esters with a fatty chain length shorter than 12 carbon atoms. The hydrolysis of esters by Malassezia lipases was detected using High Performance Thin Layer Chromatography (HPTLC). The production of free fatty acids as well as fatty alcohols was observed. The growth promotion or inhibition of bacterial strains was only found in the presence of a few ingredients. Based on these results, formulations containing microbiome inert ingredients were developed.


Cancers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 524 ◽  
Author(s):  
Juan P. Rodríguez ◽  
Carlos Guijas ◽  
Alma M. Astudillo ◽  
Julio M. Rubio ◽  
María A. Balboa ◽  
...  

Hydroxy fatty acids are known to cause cell cycle arrest and apoptosis. The best studied of them, 9-hydroxystearic acid (9-HSA), induces apoptosis in cell lines by acting through mechanisms involving different targets. Using mass spectrometry-based lipidomic approaches, we show in this study that 9-HSA levels in human colorectal tumors are diminished when compared with normal adjacent tissue. Since this decrease could be compatible with an escape mechanism of tumors from 9-HSA-induced apoptosis, we investigated different features of the utilization of this hydroxyfatty acid in colon. We show that in colorectal tumors and related cell lines such as HT-29 and HCT-116, 9-HSA is the only hydroxyfatty acid constituent of branched fatty acid esters of hydroxyfatty acids (FAHFA), a novel family of lipids with anti-inflammatory properties. Importantly, FAHFA levels in tumors are elevated compared with normal tissue and, unlike 9-HSA, they do not induce apoptosis of colorectal cell lines over a wide range of concentrations. Further, the addition of 9-HSA to colon cancer cell lines augments the synthesis of different FAHFA before the cells commit to apoptosis, suggesting that FAHFA formation may function as a buffer system that sequesters the hydroxyacid into an inactive form, thereby restricting apoptosis.


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