Chemical Composition and Structural Traits of Leaf Biomass in Selected Asparagaceae Species

This study presents an integrated chemical and anatomical characterization of leaves from seven Asparagaceae species (<i>Agave convallis</i> Trel., <i>A. salmiana</i> Otto ex Salm.-Dyck, <i>A. striata</i> Zucc., <i>Dasylirion acrotrichum</i> Zucc., <i>Nolina excelsa</i> García-Mend. & E. Solano, <i>Yucca filifera</i> Chabaud, and <i>Y. periculosa</i> Baker). Leaf biomass was subjected to successive Soxhlet extractions to quantify extractives, followed by isolation of lignocellulosic fractions. Lignin and cellulose were analyzed by Fourier-transform infrared (FTIR) spectroscopy to determine the syringyl/guaiacyl (S/G) ratio and total crystallinity index. Leaf anatomy was examined using fluorescence microscopy. Total extractives ranged from 13.4 to 24.0%, with <i>A. salmiana</i> and <i>D. acrotrichum</i> showing the highest values. Lignin content varied markedly among genera, reaching up to 45.1% in <i>Yucca</i> species, whereas cellulose content ranged from 31.3 to 42.2%. Crystalline cellulose accounted for 42.1-56.9% of total cellulose, with the highest crystallinity observed in <i>A. convallis</i>. FTIR analysis revealed a predominance of guaiacyl-type lignin in all species except <i>Y. periculosa</i> (S/G = 1.2). Multivariate analyses discriminated between genera primarily based on lignin, hemicellulose, and cellulose contents. These findings highlight genus-level differences in leaf lignocellulosic composition and support the potential use of Asparagaceae leaves as feedstocks for bioenergy and biomaterial applications.