6533b7dcfe1ef96bd1272a30
RESEARCH PRODUCT
Isomerization and increase in the antioxidant properties of lycopene from Momordica cochinchinensis (gac) by moderate heat treatment with UV-Vis spectra as a marker.
Hanh Phan-thiYves Wachésubject
IsomerizationAntioxidantHot TemperatureMomordica cochinchinensismedicine.medical_treatmentExtractionMomordica cochinchinensis (gac)Heat treatmentAntioxidantsAnalytical Chemistrychemistry.chemical_compoundPigmentLycopeneIsomerismmedicineOrganic chemistry[SDV.BBM]Life Sciences [q-bio]/Biochemistry Molecular BiologyMomordicaChromatographybiologyPlant ExtractsExtraction (chemistry)General MedicineMarkerbiology.organism_classificationCarotenoidsLycopeneHexanechemistrySpectrophotometryvisual_artNatural carotenoidsvisual_art.visual_art_mediumTroloxAntioxidantIsomerizationFood Sciencedescription
International audience; Momordica cochinchinensis (gac) is a plant rich in lycopene. This pigment tends to solubilize in oil and get damaged during extraction. The impact of heating on cis-isomerization of oil-free lycopene in hexane was studied at 50 and 80°C during 240min with UV-Vis spectrometry, DAD-HPLC and TEAC test. The initial all-trans-form isomerized to the 13-cis isomer more rapidly at 80°C. After this treatment, 16% of the lycopene compounds were in the 9-cis-form. This isomer triggered an increase in the antioxidant properties which was detectable from concentrations above 9% and resulted in a change from 2.4 to 3.7μmol Trolox equivalent. It is thus possible to increase the bioactivity of lycopene samples by controlling heating. The evolution of ratios calculated from the global UV-Vis spectrum was representative of cis-isomerization and spectrometry can thus be a simple way to evaluate the state of isomerization of lycopene solutions.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2014-08-01 | Food chemistry |