• Journal of Microbiology and Biotechnology
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• v.21 no.4
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• pp.359-365
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• 2011

Cyanobacterial strains of the genus Spirulina have recently been identified as an excellent source of sulfolipids, some of which possess anti-HIV properties. Thus, to investigate the distribution of sufolipid biosynthesis pathways in Spirulina, a genetic screening/phylogentic study was performed. Five different strains of Spirulina [Spirulina (Jiangmen), Spirulina sp., S. platensis, S. maxima, and Spirulina seawater] sourced from different locations were initially classified via 16S rDNA sequencing, and then screened for the presence of the sulfolipid biosynthesis genes sqdB and sqdX via a PCR. To assess the suitability of these strains for human consumption and safe therapeutic use, the strains were also screened for the presence of genes encoding nonribosomal peptide synthases (NRPSs) and polyketide synthases (PKSs), which are often associated with toxin pathways in cyanobacteria. The results of the 16S rDNA analysis and phylogenetic study indicated that Spirulina sp. is closely related to Halospirulina, whereas the other four Spirulina strains are closely related to Arthrospira. Homologs of sqdB and sqdX were identified in Spirulina (Jiangmen), Spirulina sp., S. platensis, and the Spirulina seawater. None of the Spirulina strains screened in this study tested positive for NRPS or PKS genes, suggesting that these strains do not produce NRP or PK toxins.

• Applied Biological Chemistry
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• v.37 no.6
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• pp.509-515
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• 1994

Using the lipids extracted from Korean yam(Dioscorea) tubers, D. batatas, D. aimadoimo and D. japonica, fractionation and identification of lipid components and their fatty acid compositions were analysed. Lipid contents determined by Folch's method in D. batatas, D. aimadoimo and D. japonica were 11.0 mg/g, 11.4 mg/g and 6.6 mg/g, respectively. Lipids extracted were fractionated into neutral lipid, glycolipid and phospholipid by silicic acid column chromatography. The content of neutral lipid was over about 60% in lipid. Neutral lipid was composed of sterol ester, triglyceride, 1,3-diglyceride, 1,2-diglyceride and monoglyceride. Main constituents of glycolipid were acylsterylglycoside, monogalactosyldiglyceride, sterylglycoside, digalactosyldiglyceride and sulfolipid, and phospholipid contained phosphatidylethanolamine, phosphatidylcholine and phosphatidylinositol. The fatty acids of the total lipid and its three lipid fractions were analyzed by GC. The major fatty acids were palmitic and linoleic acids. Content of the saturated fatty acids was less than that of the unsaturated fatty acids.

• Journal of Plant Biology
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• v.36 no.1
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• pp.97-104
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• 1993

The lipid composition of thylakoid membranes was compared between mesophyll and bundle sheath chloroplasts of maize. According to mild-denaturing gel electrophoresis, mesophyll thylakoids contained both PS I complex and PS II light-harvesting chlorophyll-protein complex(LHCP), while those of bundle sheath cells contained mainly PS I complex. The amount of lipids per mg chlorophyll was higher in bundle sheath thylakoids than in mesophyll. The major polar lipid classes were monogalactosyldiacylglycerol(MGDG), digalactosyldiacylglycreol, sulfolipid and phosphatidylglycerol (PG) in both tissues. Linolenic acid(18 : 3), linoleic acid(18 : 2) and palmitic acid(16 : 0) were the main fatty acyl components, with higher ratio of unsaturated to saturated fatty acids in bundle sheath thylakoids, suggesting these membranes are more fluid. The most striking difference in lipid composition between the two kinds of tissues was the practical absence of trans- 3-hexadecenoic acid(16 : 1t) in PG of bundle sheath thylakoids. This fatty acid is known to be involved in the association of LHCP as oligomeric form. More than 80% of MGDG molecular species was 18 : 3, 18 : 3, demonstrating that maize is a typical 18 : 3 plant. Therefore, the possibility of the functional relationships between the lamella structure, and thus the distribution of photosystems, and MGDG molecular species was excluded.