## 3 Results and Discussion
### Volatile Profile of the Samples  
Volatiles play an important role in the formation of odor and flavor [17], as well as in the bioactivity of foods [18]. In addition, some volatiles, especially terpenes and terpenoids (e.g., nerolidol, thymol, carvacrol, menthol), effectively prevent oxidation, thus contributing to the stability and shelf life of foods [45]. The volatile composition of our samples is detailed in Table S1, while the total number of volatiles in each product is shown in Figure 4. The number of total volatiles ranged between 10 (lucuma powder) and 64 (ginger powder). The contribution of the chemical classes to the total amount of volatiles is visualized in Figure 5.  
Terpenes and terpenoids usually contribute significantly to the overall aroma of foods. These compounds accounted for small proportions of the total peak area of headspace volatiles in fruit powders. In rosehip powder, several terpenes and terpenoids were present in low amounts, including D-limonene, p-cymene, isopropanol, linalol, \(\beta\)-cyclocitral, D-carvone, geranyl acetone, and \(\alpha\)-ionnone. In the goji berry powder, D-limonene and safranal were detected. The latter compound is the degradation product of carotenoids [57]. The total peak area ratios of terpenes and terpenoids were very low in the sea buckthorn, acerola, aronia, and lucuma powders. Herbs, on the other hand, contained several of these volatiles in high proportions. Turmeric powder contained 33 members of this chemical class, with high peak area percent values for ar-tumerone (20.9%), curcuminene (19.7%), tumerone (12.3%), curlone (6.2%), and zingiberene (5.8%), which is in accordance with the literature [58]. In ginger powder, 31 terpenes and terpenoids were detected, of which curcuminene (22.0%), borneol (5.7%), and \(\beta\)-bisabolene (3.2%) were the most abundant. This product contained a wide variety of mono- and sesquiterpenes that contribute to the aroma of ginger, which can be characterized as a unique and complex mixture of \begin{table}
\begin{tabular}{c c c c c c} \hline  & _Escherichia coli_ & _Escherichia coli_ & _Listeria imocua_ & _Enterococcus faecalis_ & _Enterobacter_ \\  & **ATCC 8739** & **0157:H7** & _Listeria imocua_ & _facalis_ & _cloace_ \\ \hline barley grass & - & - & - & - & - \\ wheat grass & - & - & - & - & - \\ spinach & - & - & - & - & - \\ beetroot & - & - & - & - & - \\ sea buckthorn & - & - & - & - & - \\ rosehip & ++ & + & + & - & - \\ aronia & - & - & - & - & - \\ acerola & +++ & ++ & ++ & ++ \\ goji berry & - & + & + & - & - \\ lucuma & ++ & - & - & - & - \\ spirulina & - & - & - & - & - \\ chlorella & - & - & - & - & - \\ duckweed & - & - & - & - & - \\ moringa & ++ & ++ & ++ & ++ \\ turmeric & + & + & - & - & - \\ ginger & - & + & - & - & - \\ \hline \end{tabular} - no zone of inhibition, + small zone of inhibition (<2 mm), ++ medium zone of inhibition (2–4 mm), ++ large zone of inhibition (>4 mm).  
\end{table} 
Table 5: Antibacterial potential of the investigated nutraceuticalals. spicy, woody, herbal, minty, and citrusy notes [59]. These volatiles may contribute to the bioactivity of ginger, including antioxidant, anti-inflammatory, antimicrobial, anti-cancer, neuroprotective, cardioprotective, anti-diabetic, and anti-obesity activities [60]. In the headspace of moringa powder, 19 terpen and terpenids were detected, with eucalypt showing the highest peak area ratio (3.8%). The presence of linalool and its derivatives is also noteworthy, which may contribute to the fresh, minty aroma of moringa powder with a pleasant, floral scent. The most frequently detected terpen and terpenids of the investigated nutraceuticals included geranyl acetone, \(\beta\)-ionone, \(\beta\)-cyclodextrin, and D-limonene. The latter compound was present in turmeric powder at an exceptionally high peak area ratio of 7.9%, which may provide a sweet, citrusy scent to this product. Sulfur-containing volatiles were absent from the vast majority of the samples.