Abstract：
The identification of archaeological biomarkers is one of the main objectives of analytical chemistry in the archaeological field. However, no information is currently available on biomarkers able to unambiguously indicate the presence of olive oil, a cornerstone of Mediterranean ancient societies lifestyle, in an organic residue. This study aims to bridge this gap by a thorough characterization of the degradation products of extra-virgin olive oils (EVOOs) resulting from in-lab thermal oxidative treatments, with the primary goal of revealing potential archaeological biomarkers for olive oil. Thirty-three EVOOs sourced from eleven different monocultivars across five Italian regions (Sicily, Apulia, Lazio, Tuscany, and Liguria) and Spain, were analyzed before and after thermal oxidation. In addition, an identical thermal treatment was employed on pure triglyceride standards (triolein, trilinolein, and tristearin), due to the high concentration of their fatty acids in EVOO discerning their degradation patterns. A combination of analytical strategies was employed, including HPLC-MS and HPLC-ELSD for the complete evaluation of the intact lipids (triglycerides, diglycerides, and their oxidative species) in olive oils before and after oxidation, and HS-SPME-GC-MS and GC-FID for the characterization of secondary oxidation products formed by the thermal treatment. In addition, to elucidate the fatty acid distribution in the oxidized EVOOs by GC-MS and GC-FID techniques a derivatization step was performed to convert lipid compounds into trimethylsilyl (TMS) derivatives. A chemometric approach was used to thoroughly interpret the data obtained from intact and oxidized samples. This comprehensive investigation sheds light on the chemical transformations of EVOOs under thermal oxidative conditions and indicates mono-carboxylic acids such as pentanoic, hexanoic, heptanoic, octanoic, nonanoic, and decanoic acids as potential archaeological biomarkers for the presence of lipid substances coming from olive oil in archaeological organic residues. Finally, lipid contents from twenty-four real archaeological samples, grouped in amphorae (10), unguentaria (5), and lamps (9), excavated from the Roman domus of Villa San Pancrazio in Taormina (Italy), were determined. The analytical results obtained from amphorae samples revealed the presence of the selected olive oil-specific archaeological biomarkers, an information extremely interesting considering that this type of amphorae have so far been solely associated with the storage of wine.
摘要：
考古生物标志物的鉴定是考古学领域分析化学的主要目标之一。然而,目前没有关于能够明确表明橄榄油存在的生物标志物的信息，地中海古代社会生活方式的基石，在有机残留物中。这项研究旨在通过彻底表征实验室内热氧化处理产生的特级初榨橄榄油（EVOO）的降解产物来弥合这一差距。主要目标是揭示橄榄油的潜在考古生物标志物。33种EVOO来自意大利五个地区的11种不同的单刀作物(西西里岛，普利亚,拉齐奥,托斯卡纳,和利古里亚）和西班牙，进行了热氧化前后的分析。此外,对纯甘油三酯标准品(三油精，trilinolein,和三硬脂酸甘油酯)，由于EVOO中脂肪酸的浓度很高，可以辨别它们的降解模式。采用了多种分析策略，包括HPLC-MS和HPLC-ELSD，用于完整的脂质（甘油三酯，甘油二酯，和它们的氧化物种）在氧化前后的橄榄油中，HS-SPME-GC-MS和GC-FID用于表征热处理形成的二次氧化产物。此外,为了通过GC-MS和GC-FID技术阐明氧化的EVOO中的脂肪酸分布,进行衍生化步骤以将脂质化合物转化为三甲基甲硅烷基(TMS)衍生物。化学计量学方法用于彻底解释从完整和氧化样品获得的数据。这项全面的研究揭示了在热氧化条件下EVOO的化学转化，并表明单羧酸，如戊酸，己酸,庚酸,辛酸,壬酸,和癸酸作为考古有机残留物中来自橄榄油的脂质物质存在的潜在考古生物标志物。最后,来自二十四个真实考古样本的脂质含量，按苯丙胺组(10)，Unguentaria(5),和灯（9），从陶尔米纳（意大利）的圣潘克拉齐奥别墅的罗马domus发掘，决心。从苯丙胺样品获得的分析结果表明，存在选定的橄榄油特异性考古生物标志物，这是一个非常有趣的信息，因为到目前为止，这种类型的安瓿只与葡萄酒的储存有关。
