was supposed due to be 18-hydroxyoctadecenic acid and this was confirmed by comparing the sample with the authenticated sample produced by Starmerella bombicola. The Fragmentation pattern of the sample were observed at m/z 312 [M] + (relative intensity, 1.3); m/z
produced by Candida ishiwadae, the fatty acid moieties methyl oleate and linoleyl of the compounds (a & b) having Retention Factor (Rf) values 0.23 and 0.17 was determined by the methanolysis. From the combined data of 1H-NMR and mass spectral data, the compounds (a & b) were determined to be 1-oleylglycerol and 1-linoleylglycerol. Further confirmation was done from their molecular weights, 356 and
354 [17]. In the structure elucidation of sophorolipids produced by the Candida bombicola, hydroxyl-acid methyl esters were liberated by the methanolysis and were confirmed by GC-MS. The 16-hydroxydecanoic acid was confirmed by comparing the fragmentation pattern with the standard 16-hydroxyhexadecanoic acid purchased from Sigma Aldrich. Also, an isomer 15-hydroxyhexadecanoic acid was confirmed because of the availability of the same fragmentation pattern in the library [12].
High performance liquid chromatography (HPLC) and
Liquid chromatography-mass spectroscopy (LC-MS)
In the structure elucidation of mannosylerythritol lipid from Candida sp. SY16, the acid hydrolysate of glycoside gave two spots on TLC at Rf values 0.38 and 0.46 respectively and corresponded to D-mannose and meso-erythritol. Also, in the HPLC chromatogram the peaks at RT 10.5 and 7.8 min. corresponded to D-mannose and meso-erythritol respectively. The molar ratio of D-mannose and meso- erythritol was calculated by integration of HPLC peak areas against the known concentrations of the authenticated standards and hence
294 [M-H2O]
(relative intensity, 2.4), m/z 31 [CH CH=CH ] + (relative
calculated to be 1:1 [10]. The comparative studies of sophorolipids from
intensity, 52).