Purification and Characterization of Anti-Listeria Compounds Produced by Geotrichum candidum

1998 ◽  
Vol 64 (2) ◽  
pp. 800-803 ◽  
Author(s):  
V. Dieuleveux ◽  
D. Van Der Pyl ◽  
J. Chataud ◽  
M. Gueguen
Keyword(s):  
Liquid Chromatography ◽  
Optical Rotation ◽  
Gel Filtration ◽  
Geotrichum Candidum ◽  
Infrared Spectrometry ◽  
Phenyllactic Acid ◽  
Nuclear Magnetic Resonance Spectrometry ◽  
Magnetic Resonance Spectrometry ◽  
Layer Chromatography

ABSTRACT Geotrichum candidum can produce and excrete compounds that inhibit Listeria monocytogenes. These were purified by ultrafiltration, centrifugal partition chromatography, thin-layer chromatography, gel filtration, and high-pressure liquid chromatography, and analyzed by liquid chromatography-mass spectrometry, infrared spectrometry, nuclear magnetic resonance spectrometry, and optical rotation. Two inhibitors were identified:d-3-phenyllactic acid and d-3-indollactic acid.

Chemical synthesis of sn-3-phosphatidyl sulfocholine, a sulfonium analog of lecithin

1979 ◽  
Vol 57 (6) ◽  
pp. 595-604 ◽  
Author(s):  
Paul-Alain Tremblay ◽  
Morris Kates
Keyword(s):  
Mass Spectrometry ◽  
Nuclear Magnetic Resonance ◽  
Chemical Synthesis ◽  
Optical Rotation ◽  
Phenyl Group ◽  
Elemental Analyses ◽  
Catalytic Hydrogenolysis ◽  
Nuclear Magnetic Resonance Spectrometry ◽  
Magnetic Resonance Spectrometry ◽  
Layer Chromatography

A sulfonium analog of lecithin has been reported to replace the ubiquitous phosphatidyl choline in a non-photosynthetic diatom, Nitzschia alba. The structure of this sulfonium analog has now been established by chemical synthesis using the following methods: (i) condensation of sn-3-phosphatidic acid (dimyristoyl-, dipalmitoyl-, distearoyl-, and dioleoyl-) with sulfocholine chloride in the presence of triisopropylbenzenesulfonylchloride in chloroform–pyridine (9:1); and (ii) phosphorylation of 1,2-dipalmitoyl-sn-glycerol with monophenylphosphoryl-dichloridate followed by a reaction with sulfocholine in the presence of pyridine and finally removal of the blocking phenyl group by catalytic hydrogenolysis. The desired synthetic products were obtained in overall yields of 50–70% and 11% for methods (i) and (ii), respectively, and were characterized by elemental analyses; infrared spectroscopy, nuclear magnetic resonance spectrometry, and mass spectrometry; optical rotation; and thin-layer chromatography mobilities. Comparison of the synthetic analogs with the natural sulfolecithin showed them to be identical, except for the nature of the fatty acid chains, thus establishing the natural product as sn-3-phosphatidyl sulfocholine.

scholarly journals Ekstraksi, Karakterisasi dan Uji Aktivitas Antioksidan Astaxanthin dari Produk Fermentasi Udang (Cincalok)

2021 ◽  
Vol 24 (3) ◽  
pp. 311-322
Author(s):  
Mauludia Mauludia ◽  
Thamrin Usman ◽  
Winda Rahmalia ◽  
Dwi Imam Prayitno ◽  
Siti Nani Nurbaeti
Keyword(s):  
Antioxidant Activity ◽  
High Pressure ◽  
Liquid Chromatography ◽  
High Pressure Liquid Chromatography ◽  
Aquatic Organisms ◽  
Dpph Method ◽  
Wet Weight ◽  
Tlc Analysis ◽  
Layer Chromatography

Shrimp is one of the aquatic organisms that contain several active compounds, including astaxanthin. Cincalok is one of the fermented shrimp products containing astaxanthin. This study aims to determine the characteristics of astaxanthin extract from cincalok and its antioxidant activity. Extraction of astaxanthin from cincalok was carried out using the reflux method with acetone : cyclohexane (20:80 v/v) as a solvent. The identification and characterization of astaxanthin was carried out using thin-layer chromatography (TLC), UV-Vis spectrophotometry, and High-Pressure Liquid Chromatography (HPLC). Meanwhile, the antioxidant activity test was carried out using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method in one serial concentration (5; 15; 25 ppm). The results of TLC analysis showed that astaxanthin in cincalok extract has Rf value (0.32). The analysis using a UV-Vis spectrophotometer produced a spectrum with a maximum wavelength of 477 nm, which corresponds to the maximum wavelength of standard astaxanthin. The yield of astaxanthin extract from cincalok in this study was 1.47 mg/100 g wet weight. The chromatogram from the results of UHPLC analysis showed that the retention time of cincalok astaxanthin extract was 6.27 minutes with a purity of 18.03%. The antioxidant activity of cincalok astaxanthin extract was 568.32 ppm. Udang merupakan salah satu organisme air yang mengandung banyak senyawa aktif, termasuk astaxanthin. Cincalok merupakan salah satu produk hasil fermentasi udang yang mengandung astaxanthin. Penelitian ini bertujuan untuk mengetahui karakteristik ekstrak astaxanthin dari cincalok dan aktivitas antioksidannya. Ekstraksi astaxanthin dari cincalok menggunakan metode refluks dengan pelarut aseton:sikloheksan (20:80 v/v). Identifikasi dan karakterisasi astaxanthin dilakukan dengan menggunakan kromatografi lapis tipis (KLT), spektrofotometri UV-Vis, dan High Pressure Liquid Chromatography (HPLC). Sedangkan uji aktivitas antioksidan dilakukan menggunakan metode 1,1-difenil-2-pikrilhidrazil (DPPH) dengan memvariasikan konsentrasi larutan uji, yaitu 5; 15; 25 ppm. Hasil dari penelitian ini melaporkan astaxanthin pada ekstrak cincalok menunjukkan nilai Rf 0,32 pada kromatografi lapis tipis (KLT). Hasil analisis menggunakan spektrofotometer UV-Vis menghasilkan spektra dengan panjang gelombang maksimum 477 nm, yang sesuai dengan panjang gelombang maksimum astaxanthin standar. Randemen ekstrak astaxanthin dari cincalok pada penelitian ini adalah 1,47 mg/100 g berat basah. Kromatogram dari hasil analisis UHPLC menunjukkan waktu retensi ekstrak astaxanthin cincalok yaitu selama 6,27 menit dengan kemurnian sebesar 18,03%. Aktivitas antioksidan dari ekstrak astaxanthin cincalok diperoleh sebesar 568,32 ppm.  

scholarly journals Natural Dyes from Mortiño (Vaccinium floribundum) as Sensitizers in Solar Cells

Energies ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 785 ◽  
Author(s):  
Miguel A. Taco-Ugsha ◽  
Cristian P. Santacruz ◽  
Patricio J. Espinoza-Montero
Keyword(s):  
High Performance Liquid Chromatography ◽  
Solar Cells ◽  
Liquid Chromatography ◽  
Solar Cell ◽  
High Performance ◽  
Power Conversion ◽  
Natural Dyes ◽  
The Cost ◽  
Layer Chromatography

Photovoltaic energy presents environmental advantages; however, these advantages are limited by the cost of manufacturing solar cells and in many cases, scarce or dangerous materials are incorporated. Therefore, the use of natural dyes from mortiño (Vaccinium floribundum) as sensitizers in solar cells is proposed. The dyes were extracted by maceration in acidified methanol (HCl, citric acid and trifluoroacetic acid TFA) and were characterized by High-Performance Liquid Chromatography (HPLC), Thin-Layer Chromatography (TLC) and spectrometric methods (UV-Vis, IR and MS-MALDI). The construction and characterization of cells were in standard conditions. The study confirms that pigments in mortiño are flavonoids of the anthocyanidin group as: cyanidin-3-galactoside, and cyanidin-3-arabinoside. The efficiency of solar cells was between 0.18–0.26%; the extraction with TFA in methanol leads to the best performance. Although they have low power conversion efficiency, mortiño dyes could be an alternative to artificial sensitizers for solar cell technologies because they are harmless and abundant substances.

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