College of Forestry, Shanxi Agricultural University, Taigu, 030801, Shanxi, China.
Sci Rep. 2024 Aug 10;14(1):18612. doi: 10.1038/s41598-024-69600-3.
Essential oils (EOs) are complex and susceptible to environmental conditions, they have a wide range of biological activities and are often used to differentiate between similar species. In this study, gas chromatography-mass spectrometry (GC-MS) coupled with chemometric analysis was applied to systematically analyse and evaluate EOs constituents and antioxidant activity of six Chinese Cupressaceae taxa (Platycladus orientalis Franco, P. orientalis Franco 'Sieboldii', P. orientalis Franco 'Aurea', Juniperus chinensis Roxb., J. chinensis Roxb. 'Kaizuca', and J. sabina L.) under identical conditions. The antioxidant activity of the EOs was evaluated using 2,2 -diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and ferric reducing power (FRAP), and the total phenolic content (TPC) of the EOs was determined by Folin-Ciocalteau reagent. In total, seventy individual constituents were identified with the main components being α-pinene, sabinene, D-limonene, bornyl acetate, δ-3-carene and β-myrcene. Principal component analysis (PCA) and hierarchal cluster analysis (HCA) successfully discriminated the six taxa into three chemotypes and the unique chemotype revealed that J. chinensis 'Kaizuca' may be a species rather than a cultivar of J. chinensis. The results of OPLS-DA analysis showed that the three compounds screened, namely, α-pinene, sabinene, and δ-3-carene, can completely distinguish Platycladus spp. from Juniperus spp. The DPPH assay results ranged from 576.14 (J. chinensis 'Kaizuca') to 1146.12 (J. sabina) μmol eq Trolox/mL EO, while the ABTS values ranged from 1579.62 (P. orientalis 'Aurea') to 5071.82 (J. sabina) μmol eq Trolox/mL. In the FRAP assay, the values ranged from 1086.50 (J. chinensis 'Kaizuca') to 1191.18 (J. sabina) μmol eq Trolox/ml and the TPC of the EOs studied ranged from 15.17 (J. chinensis 'Kaizuca') to 39.37 (J. sabina) mg GAE/mL EO. The results consistently showed that J. sabina possessed the strongest antioxidant activity and can be preferentially used as a rich source of potentially natural antioxidants.
精油（EOs）是复杂的，易受环境条件的影响，它们具有广泛的生物活性，常用于区分相似的物种。在这项研究中，气相色谱-质谱联用（GC-MS）结合化学计量学分析被应用于系统地分析和评估六种中国柏科植物（侧柏 Franco、侧柏 Franco 'Sieboldii'、侧柏 Franco 'Aurea'、柏 Juniperus chinensis Roxb.、柏 Juniperus chinensis Roxb. 'Kaizuca' 和圆柏 Juniperus sabina L.）的精油成分和抗氧化活性。使用 2,2-二苯基-1-苦基肼（DPPH）、2,2'-联氮-双（3-乙基苯并噻唑啉-6-磺酸）（ABTS）和铁还原能力（FRAP）评估精油的抗氧化活性，并通过 Folin-Ciocalteau 试剂测定精油的总酚含量（TPC）。总共鉴定出 70 种单体成分，主要成分为α-蒎烯、β-蒎烯、D-柠檬烯、乙酸龙脑酯、δ-3-蒈烯和β-月桂烯。主成分分析（PCA）和层次聚类分析（HCA）成功地将这 6 个分类群分为 3 个化学型，独特的化学型表明，J. chinensis 'Kaizuca'可能是一个种而不是 J. chinensis 的一个栽培品种。OPLS-DA 分析结果表明，筛选出的三种化合物，即α-蒎烯、β-蒎烯和 δ-3-蒈烯，可完全区分柏科和柏科。DPPH 测定结果范围为 576.14（J. chinensis 'Kaizuca'）至 1146.12（J. sabina）μmol eq Trolox/mL 精油，而 ABTS 值范围为 1579.62（P. orientalis 'Aurea'）至 5071.82（J. sabina）μmol eq Trolox/mL。在 FRAP 测定中，数值范围为 1086.50（J. chinensis 'Kaizuca'）至 1191.18（J. sabina）μmol eq Trolox/ml，研究精油的 TPC 范围为 15.17（J. chinensis 'Kaizuca'）至 39.37（J. sabina）mg GAE/mL 精油。结果一致表明，J. sabina 具有最强的抗氧化活性，可优先用作潜在天然抗氧化剂的丰富来源。
