Comparative Analysis and Evaluation of Nutritional Value in Eight Dendrobium Species

Dendrobium species had been traditionally utilized for their medicinal properties and nutritional benefits. Understanding the nutritional variations among different Dendrobium species was crucial for their optimal utilization. This study systematically evaluated eight Dendrobium species (D. strongylanthum, D. chrysanthum, D. chrysotoxum, D. lituiflorum, D. scoriarum, D. aduncum, D. hercoglossum, and D. lohohense) by analyzing their general nutritional components, mineral elements, bioactive constituents, and amino acid profiles. The results revealed that all eight Dendrobium species exhibited a low-fat nutritional characteristic (ranging from 0.98% to 1.74%) and high levels of Mg (ranging from 1.03×10³ to 6.06×10³ mg/kg), K (ranging from 0.39×10⁴ to 1.66×10⁴ mg/kg), and Ca (ranging from 0.3×10⁴ to 2.33×10⁴ mg/kg). D. strongylanthum and D. lituliflorum contained higher polysaccharide contents (51.11% and 38.91%, respectively). Moreover, the alcohol-soluble extract contents of all Dendrobium species were above 6.5%, with the exception of D. aduncum. All species contained a complete profile of amino acids, with total amino acid content ranging from 1.395% to 3.883%, and essential amino acids accounting for 36.00% to 41.12% of the total, indicating their potential as high-quality protein sources. Statistical analysis demonstrated a highly significant positive correlation between total amino acids and essential amino acids (r=0.92, P<0.01) as well as medicinal amino acids (r=0.89, P<0.01), A moderate but significant correlation was observed with the amino acid score (r=0.68, P<0.05). Whereas no significant association was found with bioactive constituents (P>0.05). Cluster analysis categorized the eight species into three distinct groups, revealing substantial nutritional heterogeneity even within closely related taxa. D. strongylanthum and D. lituiflorum (Group I) emerged as superior cultivars, exhibiting not only exceptional polysaccharide content but also markedly higher total amino acid levels (3.883% and 3.041%, respectively) compared to other species. These findings position them as priority candidates for selective breeding and development as premium Dendrobium resources.