## 4 Discussion  
### Elderberry Steam Distillation  
Based on the calculated _dried herb-to-hydrolate ratio_, the results highlight an efficient transfer of aromatic, volatile compounds from elderberries, showcasing the proficiency of the extraction process and, ultimately, potential for therapeutic or cosmetic applications, also emphasizing the importance of steam distillation as a sustainable extraction technique. However, it has to be taken into account that variations in the _dried herb-to-hydrolate ratio_ may arise from factors like the plant material characteristics, distillation parameters, and handling during collection and separation, while these may significantly affect the distillation efficiency. The observed pH level affects the potential applications and emphasizes the need for precise quality control. Adjusting the pH for specific applications may enhance elderberry hydrolate's utility in various industries. This study explores elderberry's potential for use in natural cosmetics, investigating steam distillation as an accessible method for obtaining elderberry hydrolate. The findings contribute to understanding elderberry's benefits for skin health, emphasizing steam distillation's sustainability for aromatic and therapeutic extraction. Moreover, to the best of our knowledge, this is the first study on the composition and in vitro biological properties of elderberry hydrolate. This study also contributes to a better understanding of the characterization of the volatile constituents of elderberry hydrolate. In the analysis of hydrolates, liquid-liquid extraction is usually used to extract the volatile compounds into an organic solvent due to limitations of GC-MS as a tool for analyzing aqueous samples [22]. Hexane is most commonly used as an organic solvent [23], although it is not an optimal extraction solvent for the purpose of identifying the composition of an hydrolate, as it is a highly non-polar solvent (logP = 3.90). Therefore, we additionally used extraction with ethyl acetate, which is more polar (logP = 0.73) than hexane but still does not mix with water. Considering that a hydrolate is an aqueous solution of volatile compounds and that polar volatile compounds are present in higher contents than less polar ones, we expected to detect more compounds in the ethyl acetate extract. However, this was not the case; we could only detect phenylacetaldehyde in the ethyl acetate extract, while (_E_)-beta-damascenone, n-hexanal and furfural were also detected in the hexane extract, but in trace amounts. Generally, the total number of compounds detected in an hydrolate depends on the method chosen to analyze the hydrolate, with fewer compounds expected to be detected when the hydrolate is applied directly to the GC-MS, i.e., without pretreatment or preparation of the sample, than when it is previously extracted with an organic phase such as hexane or ethyl acetate. Considering this, we conclude that both direct GC-MS analysis of unprocessed hydrolate as well as the analysis of extracts are necessary to obtain the most detailed information possible about the composition of an hydrolate. Elderberry has been widely recognized for its diverse array of bioactive compounds, including antioxidants, vitamins, and essential fatty acids [5]. The antioxidant propertiesof elderberry are of particular interest, as they hold the potential to counteract oxidative stress and prevent premature aging. This aligns with previous studies that have suggested elderberry's capacity to protect the skin from free radical damage [8]. These findings also underline elderberry's anti-inflammatory and antimicrobial properties, which contribute to its ability to soothe irritated skin and defend against potential infections. The antigenotoxic properties reported in elderberry are of significant interest, suggesting a connection between its usage and anti-aging benefits. Altogether, elderberry's multifaceted attributes position it as a promising natural ingredient for enhancing skin health and addressing various skin concerns.