## 3 Results and Discussion
### Quality Marker Regions and Their Significance
Both IR and Raman spectroscopy have been among the most widely used instruments employed in the characterization of plant constituents including cellulose [61, 62]. FT-IR spectroscopy has been successfully used to confirm the crystalline structure or to analyze chemical constituents of various ligno-cellulosic materials, not limited to textile plants but wood as well. In this sense, the study of wood powder from _Pinus sylvestris_ var. _mongolica_ after alkali treatment displayed changes in crystalline structure marked by spectral changes including a decrease in intensity of the band from 1428 cm\({}^{-1}\) and a shift at 1418 cm\({}^{-1}\). Additionally, the disappearance of the peak at 1507 cm\({}^{-1}\) from purified wood pulp was attributed to the removal of lignin, while the peak at 1737 cm\({}^{-1}\) was attributed to the leaching of hemicellulose after treatments with alkali [63]. Spectra of pure cellulose \(\lg\) film analyzed comparatively through vibrational methods IR and Raman allowed the identification of vibrational modes of crystalline cellulose, while also highlighting differences and correspondence among bands of spectra obtainedthough these techniques. The spectral region below 1000 cm\({}^{-1}\) can be considered as a domain of skeletal deformation vibration modes both for IR and Raman, followed until 1500 cm\({}^{-1}\) with regions that exhibit bands associated with highly delocalized skeletal stretching. However, C-O stretches around 1000 cm\({}^{-1}\) as well as polar group vibration modes (OH stretches) in 3200-3600 cm\({}^{-1}\) were shown to be stronger in IR than in Raman spectra, while CH and CH\({}_{2}\) stretches around 2800-3000 cm\({}^{-1}\) are prominent in both [62]. Vibrational spectroscopy remains a facile analysis technique for plant samples. The optimization of these characterization methods for plant-based raw materials can extend their practical applications. Cellulose from textile plants is the starting material for many derivatives [64] depending on the destination of use. Chemically unaltered cellulose, known as cellulose I, is characterized by a specific crystal form. After treatments, cellulose experiences changes in properties and characteristics, particularly its crystal structure, leading to so-called cellulose II, III and IV being obtained. These treatments are meant to restructure the cellulose to obtain lattice structuring or to stretch the fibers [35], all these being required for processing and various optimized uses. The analysis of cellulose in the native state as it is found in textile plants before any significant structural modifications take place through processing, such as changes in the orientation of chains that occur following mererization [65], can provide a characterization at the point \"0\" of the primary state in which cellulose is found in raw material. The identification of cellulose-specific regions in stems of given textile plants provides the basis and starting point for qualitative sorting and preliminary qualitative characterization. This could prove useful for deciding the destination of use of the raw material according to desired cellulose parameters or to select for further processes a specific type of stem according to pre-established criteria.