Zhang Lin

Variability of seed oil content and fatty acid composition in Shantung maple (Acer truncatum Bunge) germplasm for optimal biodiesel production

Shantung maple seed oil methyl esters have emerged as the potential feedstock for producing biodiesel. The goal of this work was to assess variations in seed oil content and fatty acid compositions for optimal biodiesel production among 138 Shantung maple accessions native to 14 regions of China. Dramatic differences in seed oil content were observed among trees grown in the various regions tested; seeds of trees grown in Daiqintala, Inner Mongolia (DQTL) and Yongshou, Shaanxi (YS) exhibited the highest oil content (32.47 and 32.09%, respectively). Among the 138 germplasm accessions, seed oil content ranged from 17.81 to 36.56%, with a mean value of 28.57%. Of a total of 15 fatty acid components detected overall, oleic acid and linoleic acid comprised the highest proportions of fatty acids (20 to 34.31% and 27.08 to 36.71%, respectively). Correlation analysis revealed the highest positive correlation between oleic acid and cis-11-eicosenoic acid (0.698) and the highest negative correlation between oleic acid and linoleic acid (-0.766). Ranges of saponification number (180.26 to 182.86), iodine value (101.84 to 113.70 g I2/100 g), cetane number (50.77 to 53.53), density (873.03 to 880.08 kg/m3) and kinematic viscosity (4.92 to 5.28 mm2/s) confirmed that Shantung maple methyl esters are suitable for biodiesel production, and correlation analysis showed that the accession with high monounsaturated fatty acid content was suitable as optimal germplasm resources for biodiesel production. DQTL, YS and Taian, Shandong (TA) regions was considered the best plantation, and DQTL-1, DQTL-6, DQTL-8, YS-6, and TA-10 germplasm accessions generated oil with optimal properties for biodiesel production. These results could guide future development of Shantung maple seed oil for improved biodiesel production. n n Key words: Acer truncatum Bunge, biodiesel properties, fatty acid composition, oil content, variation.