Renewable Materials Research Centre (CRMR) and Institute of Nutrition and Functional Foods (INAF), Université Laval, Quebec, QC, G1V 0A6, Canada.
Centre for Forest Research and Institute of Integrative and Systems Biology, Université Laval, Quebec, QC, G1V 0A6, Canada.
Sci Rep. 2021 Nov 2;11(1):21524. doi: 10.1038/s41598-021-01091-y.
Thermally assisted Hydrolysis and Methylation (THM), and 2D-heteronuclear single quantum coherence nuclear magnetic resonance (2D HSQC NMR) spectroscopy were used to monitor the transformation of ramial chipped wood (RCW) from Gmelina arborea and Sarcocephalus latifolius, together with their organosolv lignins, following soil incubation in Benin (West Africa). Mesh litterbags containing RCW were buried in soils (10 cm depth) and were retrieved after 0, 6, 12 and 18 months of field incubation. Chemical analysis showed that total carbohydrate content decreased, while total lignin content increased as RCW decomposition progressed. Ash and mineral content of RCW increased significantly after 18 months of decomposition in soil. Significant N-enrichment of the RCW was determined following 18 months incubation in soils, reaching 2.6 and 1.9 times the initial N-content for G. arborea and S. latifolius. Results of THM showed that the S + G sum, corresponding to lignins, increased with RCW residence time in the soils, in contrast to the response of compounds derived from carbohydrates, the sum of which decreased. Remarkably, lignin interunit linkages, most notably β-O-4' aryl ethers, β-β' resinol, β-5' phenylcoumaran and p-PCA p-coumarate, survived after 18 months in the soil, despite their gradual decrease over the duration of the experiment.
热辅助水解和甲基化（THM）以及二维异核单量子相干核磁共振（2D HSQC NMR）光谱被用于监测来自 Gmelina arborea 和 Sarcocephalus latifolius 的枝桠碎木（RCW）及其有机溶剂木质素在贝宁（西非）土壤培养过程中的转化。含有 RCW 的网眼袋被埋在土壤中（深度为 10 cm），并在野外培养 0、6、12 和 18 个月后取回。化学分析表明，随着 RCW 分解的进行，总碳水化合物含量减少，而总木质素含量增加。RCW 的灰分和矿物质含量在土壤中分解 18 个月后显著增加。在土壤中培养 18 个月后，确定 RCW 明显富集了 N，达到 G. arborea 和 S. latifolius 初始 N 含量的 2.6 和 1.9 倍。THM 的结果表明，与木质素相对应的 S + G 总和随着 RCW 在土壤中的停留时间增加而增加，而与碳水化合物衍生化合物的反应相反，其总和减少。值得注意的是，木质素的单元间连接键，特别是 β-O-4'芳基醚、β-β'树脂醇、β-5'苯基香豆素和 p-PCA 对香豆酸酯，尽管在实验过程中逐渐减少，但在土壤中仍能存活 18 个月。
