Chemical composition profiling of Oldeania alpina culm layers across developmental ages

The demand for non-renewable chemical and material resources continues to rise as fossil fuel reserves dwindle. As the limitations of fossil fuel-driven industries become increasingly evident, there is an urgent need for sustainable alternatives. This study investigated the chemical composition of inner, middle, and outer internodal culm layers from 1-, 3-, and 5-year-old Oldeania alpina, which is cultivated in the Amhara region, Banja district, northwest Ethiopia. Culm samples were cleaned, separated into layers, dried, and ground to a 40–60 mesh size using a Wiley mill. Lignocellulose components (cellulose, lignin, and hemicellulose), extractives, ash, and moisture contents were quantified. Lignin and hemicellulose were determined according to ASTM standards, and cellulose was analysed using the Kurschner and Hoffer method. Significant variations in lignocellulosic composition, extractives, ash, and moisture were observed across culm ages and layers. The highest lignin (28.06%), alpha cellulose (58.54 ± 0.16%), and cellulose (59.25%) contents were recorded in the outer layer of 5-year-old culms, while hemicellulose (13.48%) peaked in the outer layer of 3-year-old culms. The inner layer of 1-year-old culms showed maximum extractives (18.64%), moisture (19.68%), and ash (5.16%). To the best of our knowledge, this is the first integrated report of age- and layer-dependent chemical variations in O. alpina. Overall, these results offer new insights into the sustainable exploitation of O. alpina as a renewable resource and underscore its potential as a valuable raw material for bioenergy and biochemicals.