The lipid content and composition in tender, medium and coarse leaves of 3 mulberry varieties were analyzed. Tender leaf contained more lipid than medium and coarse leaves. Fatty acid composition of lipids also varied...The lipid content and composition in tender, medium and coarse leaves of 3 mulberry varieties were analyzed. Tender leaf contained more lipid than medium and coarse leaves. Fatty acid composition of lipids also varied with leaf maturity. Tender leaf contained more precursor fatty acids, medium leaf more unsaturated fatty acids and coarse leaf more saturated fatty acids. V-1 mulberry variety had more foliar lipid con- tent than S-36 and M-5. Lipid composition also varied among the 3 mulberry varieties. V-1 and S-36 leaves contained more unsaturated fatty acids and M-5 more saturated fatty acids. V instar silkworm was fed with the medium leaf of the 3 mulberry varieties, and the total lipid content and fatty acid composition of the haemolymph, fatbody and excreta were analyzed. Lauric acid （12：0）, undetectable in the haemolymph, was recovered in significant quantity in the excreta. Saturated fatty acids （16：0 and 18：0） were higher in the haemolymph of larvae fed on M-5 while unsaturated fatty acids （18：2 and 18：3） were higher in those fed on S-36 and V-1 leaves. But, the percentage levels of 18：1 and 18：2 fatty acids in the leaf and haemolymph were swapped. While the leaf of M-5 mulberry variety had 18：1 and 18：2 fatty acid components at 1.93% and 16.8%, the larvae feeding on the leaf had 18：1 and 18：2 at 21.5% and 6.95% in the haemolymph. Similar correction in the percentages of the two unsaturated fatty acids was observed in the larvae feeding on the leaves of S-36 and V-1. Saturation of co -6 double bond of linoleic acid by a reductase in the lower end of the midgut was proposed.展开更多
文摘The lipid content and composition in tender, medium and coarse leaves of 3 mulberry varieties were analyzed. Tender leaf contained more lipid than medium and coarse leaves. Fatty acid composition of lipids also varied with leaf maturity. Tender leaf contained more precursor fatty acids, medium leaf more unsaturated fatty acids and coarse leaf more saturated fatty acids. V-1 mulberry variety had more foliar lipid con- tent than S-36 and M-5. Lipid composition also varied among the 3 mulberry varieties. V-1 and S-36 leaves contained more unsaturated fatty acids and M-5 more saturated fatty acids. V instar silkworm was fed with the medium leaf of the 3 mulberry varieties, and the total lipid content and fatty acid composition of the haemolymph, fatbody and excreta were analyzed. Lauric acid （12：0）, undetectable in the haemolymph, was recovered in significant quantity in the excreta. Saturated fatty acids （16：0 and 18：0） were higher in the haemolymph of larvae fed on M-5 while unsaturated fatty acids （18：2 and 18：3） were higher in those fed on S-36 and V-1 leaves. But, the percentage levels of 18：1 and 18：2 fatty acids in the leaf and haemolymph were swapped. While the leaf of M-5 mulberry variety had 18：1 and 18：2 fatty acid components at 1.93% and 16.8%, the larvae feeding on the leaf had 18：1 and 18：2 at 21.5% and 6.95% in the haemolymph. Similar correction in the percentages of the two unsaturated fatty acids was observed in the larvae feeding on the leaves of S-36 and V-1. Saturation of co -6 double bond of linoleic acid by a reductase in the lower end of the midgut was proposed.
