Chemical Composition of Cacti Wood and Comparison with the Wood of Other Taxonomic Groups

Abstract

The aims of this study were to determine the wood chemical composition of 25 species of Cactaceae and to relate the composition to their anatomical diversity. The hypothesis was that wood chemical components differ in relationship to their wood features. The results showed significant differences in wood chemical compounds across species and genera (P < 0.05). Pereskia had the highest percentage of lignin, whereas species of Coryphantha had the lowest; extractive compounds in water were highest for Echinocereus, Mammillaria, and Opuntia. Principal component analysis showed that lignin proportion separated the fibrous, dimorphic, and non-fibrous groups; additionally, the differences within each type of wood occurred because of the lignification of the vascular tissue and the type of wall thickening. Compared with other groups of species, the Cactaceae species with fibrous and dimorphic wood had a higher lignin percentage than did gymnosperms and Acer species. Lignin may confer special rigidity to tracheary elements to withstand desiccation without damage during adverse climatic conditions.

Enhancement of the Amazonian Açaí Waste Fibers through Variations of Alkali Pretreatment Parameters

“…When compared with raw açaí fibers, the pretreated ones showed darker coloring, confirming a greater exposure of lignin after the alkaline pretreatments ( Figure f ). In the wood, lignin may confer special rigidity to the vessel elements to withstand desiccation without damage during adverse climatic conditions . As the açaí fibers cover the seeds, lignin possibly also has a protective function against adverse climatic conditions.…”

Differences in the Structural Chemical Composition of the Primary Xylem of Cactaceae: A Topochemical Perspective

“…The amount of sample required to extract and quantify extractives, Klason lignin, cellulose, and hemicellulose was adapted from the methodology of the TAPPI T-222 om-02 norm. This method has been used in studies of wood (Dence, 1992; Wahab et al, 2013) and fibers (Han and Rowell, 1996), including adult plants of Cactaceae (Reyes-Rivera et al, 2015; Maceda et al, 2018). For each one of the eight species, 75 seedlings were dried and milled and the material was homogenized.…”

“…The extractive-free stem samples were obtained by successive extractions in Soxhlet (Reyes-Rivera and Terrazas, 2017), with ethanol/benzene (1:2, v / v ) and 96% ethanol; each of the extractions took 24 cycles, which were 5 h approximately. The cartridges were left to dry for 12 h to obtain constant weight (Maceda et al, 2018). The samples were removed from the cartridges and they were extracted in distilled water for an hour at 95°C, filtered through a medium-pore Büchner filter, and kept at 105°C for 12 h and their constant weight was recorded (Maceda et al, 2018).…”

“…The chemical composition of secondary metabolites, analyzed by phytochemical profiling, has allowed the identification of the principal compounds in the stem (Loza-Cornejo et al, 2017), the structural chemical composition of stem conductive tissues (Reyes-Rivera et al, 2015; Maceda et al, 2018; Reyes-Rivera et al, 2018), and from other structures such as glochids and spines in several cacti species (Pritchard and Hall, 1976; Kohl et al, 2014).…”

“…The structural chemical composition of the secondary xylem of Cactaceae has been studied in fibrous, non-fibrous, and dimorphic species. The lignin concentration is the main component to distinguish fibrous species from non-fibrous ones (Maceda et al, 2018); also, the composition of lignin monomers is heterogeneous in non-fibrous and dimorphic species, but the occurrence of syringyl and guaiacyl is homogeneous in fibrous species (Reyes-Rivera et al, 2015; Reyes-Rivera et al, 2018). In addition, cellulose and lignin percentages differ with other families and between Cactaceae genera (Maceda et al, 2018).…”