Agarwood formation in traditional Aquilaria sinensis is challenging. However, through selective breeding, a fast, high-yielding, and high-quality Qi-Nan agarwood has been developed from Aquilaria sinensis. To elucidate the applicable methods for agarwood formation, experiments were conducted using drilling at different distances to clarify the agarwood formation conditions and provide production guidance. In this study, Qi-Nan agarwood resin formation was induced by using drilling at different distances of 4 cm (FD), 8 cm (ED), and 16 cm (SD). GC-MS analysis identified 70 volatile constituents, including aromatic compounds, sesquiterpenes, fatty acids/esters, and PECs, with PECs and sesquiterpenes being the predominant components, whereas no sesquiterpenes or PECs were detected in the control group (CK). Furthermore, UPLC-MS analysis identified 85 non-volatile PECs in Qi-Nan agarwood, with FTPECs contents being the most abundant. Metabolomic analysis further differentiated samples subjected to varying stress levels (SD and E-FD), providing future opportunities for metabolic or biosynthetic pathway investigations. After 12 months of treatment, the agarwood quality was markedly superior with the ED treatment group, the ethanol extract content was 46.60 %±0.73 %, essential oil constituted 40.47 %±0.91 %, and the relative contents of PECs and sesquiterpenes were 64.39 % and 27.50 %, respectively. Additionally, DPPH and ABTS⁺ exhibited low IC₅₀ values of 0.1271 mg/mL and 0.0283 mg/mL, respectively. The MS² fragmentation pathways of chromone compounds were validated based on chromone-derived fragment ions. These results indicate that drilling treatments, particularly the ED method, using Qi-Nan agarwood germplasm can effectively enhance both the yield and quality of agarwood.

中文翻译：

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基于齐南沉香钻孔法的沉香品质及特征化学成分分析


传统沉香木的形成具有挑战性。然而，通过选择性育种，从 Aquilaria sinensis 开发出一种快速、高产、高质量的齐南沉香。为阐明沉香形成的适用方法，采用不同距离钻孔进行实验，阐明沉香形成条件，提供生产指导。在这项研究中，通过在 4 cm （FD） 、 8 cm （ED） 和 16 cm （SD） 的不同距离钻孔来诱导齐南沉香树脂的形成。GC-MS 分析鉴定出 70 种挥发性成分，包括芳香族化合物、倍半萜、脂肪酸/酯和 PEC，其中 PECs 和倍半萜是主要成分，而对照组 （CK） 未检测到倍半萜或 PEC。此外，UPLC-MS 分析在齐南沉香中鉴定出 85 种非挥发性 PEC，其中 FTPECs 含量最丰富。代谢组学分析进一步区分了承受不同应激水平（SD 和 E-FD）的样品，为代谢或生物合成途径研究提供了未来的机会。处理12个月后，ED处理组沉香品质明显优于沉香，乙醇浸出物含量为46.60 %±0.73 %，精油含量为40.47 %±0.91 %，PECs和倍半萜类化合物的相对含量分别为64.39 %和27.50 %。此外，DPPH 和 ABTS⁺ 的 IC₅₀ 值较低，分别为 0.1271 mg/mL 和 0.0283 mg/mL。基于色酮衍生的碎片离子验证了色酮化合物的 MS² 碎裂途径。 这些结果表明，利用齐南沉香木种质进行钻孔处理，特别是 ED 法可以有效提高沉香的产量和品质。