Laboratory of Chemometrics and Environmental Applications, ISPRA: Istituto Superiore Per La Protezione E La Ricerca Ambientale, Via di Castel Romano 100, 00128, Rome, Italy.
Laboratory of Biodiversity Protection, ISPRA: Istituto Superiore Per La Protezione E La Ricerca Ambientale, Via di Castel Romano 100, 00128, Rome, Italy.
Environ Sci Pollut Res Int. 2022 Apr;29(19):28725-28742. doi: 10.1007/s11356-021-17818-3. Epub 2022 Jan 6.
In the present study, we applied Fourier transform infrared (FTIR) and Fourier transform near infrared (FTNIR) spectroscopy to investigate some specific structural aspects of Patella caerulea, Mytilus edulis, Ostrea edulis, and Calista chione shells sampled in different sites. Moreover, for Ostrea edulis and Calista chione, the present study also included fossil samples. As far as FTIR spectroscopy is concerned, the support of statistical and multivariate methods such as the average spectrum (AV), spectral deconvolution, and two-dimensional correlation analysis (2DCOS) allowed to detect structural differences existing within the same mollusc species as a function of the sites they come. These differences can be reasonably linked to the local environmental conditions, which affect the biomineralization pattern of shell formation and growth. These structural differences are related to the calcite, aragonite, Mg-calcite contents, and interactions, as presently observed for fresh and fossil shells. The application of 2DCOS and deconvolution to FTIR spectra also showed the role of the amorphous calcium carbonate (ACC) in the structural characterization of shells, then suggesting the use of a new parameter, the calcite and aragonite to ACC (CAACC) ratio, as a new measurement for the structural characterization of shells. At last, FTNIR spectroscopy allowed detecting the presence of α-helix and β-sheet protein structures in the shells. The results of this study show that also FTIR and FTNIR spectroscopy are able to discern differences in structural characteristics of mollusc shells, a field of environmental studies where scanning electron microscopy and X-ray diffraction are the more widely used methods.
在本研究中，我们应用傅里叶变换红外（FTIR）和傅里叶变换近红外（FTNIR）光谱法研究了在不同地点采集的贻贝、牡蛎、紫贻贝和海扇贝壳的一些特定结构方面。此外，对于牡蛎和海扇，本研究还包括了化石样本。就 FTIR 光谱而言，统计和多元方法（如平均光谱（AV）、光谱解卷积和二维相关分析（2DCOS））的支持，使得可以检测到同一软体动物物种内存在的结构差异，这些差异与它们来自的地点有关。这些差异可以合理地与影响壳形成和生长的生物矿化模式的局部环境条件联系起来。这些结构差异与方解石、霰石、Mg-方解石的含量和相互作用有关，如目前观察到的新鲜和化石贝壳。2DCOS 和解卷积在 FTIR 光谱上的应用也显示了无定形碳酸钙（ACC）在壳结构表征中的作用，然后提出了使用新参数，即方解石和霰石与 ACC（CAACC）的比例，作为壳结构表征的新测量方法。最后，FTNIR 光谱法可以检测到壳中α-螺旋和β-折叠蛋白结构的存在。本研究的结果表明，FTIR 和 FTNIR 光谱法也能够区分软体动物壳的结构特征差异，这是环境研究领域，扫描电子显微镜和 X 射线衍射是更广泛使用的方法。
