## 3 Results and Discussion
### In Vitro Antiplatelet Activity
Moreover, Platelet Activating Factor, due to its biochemical actions, has attracted the attention of the scientific community as a molecule involved in all the fundamental states of the development of atherosclerosis, the inhibition of which could be a way to counteract the development of atherosclerosis and, by extension, the prevention of cardiovascular diseases [24]. Results concerning total phenolic and flavonoid content in Limnio grape pomace are in line with recent studies that showed total phenolics in the range of 33.39 \(\pm\) 0.59 to 92.15 \(\pm\) 1.75 mg GAE/g [36; 37; 38] and total flavonoids in the range of 12.15 \(\pm\) 1.20 to 51.36 mg quercetin equivalent/g [36], depending on the extraction conditions. On the other hand, other investigators have determined lower total phenolics in aquafaba (5.50 mgGAE/g) compared to our study (18.87 mgGAE/g) [39]. This difference may exist due to the different varieties and storage conditions of chickpeas [40]. The Limnio grape pomace extract and freeze-dried aquafaba of Lemnian chickpeas from Panagia exhibit a notably greater concentration of total phenolics in comparison to tahini (44.86 \(\pm\) 3.32 and 18.87 \(\pm\) 0.66 \(>\) 6.02 \(\pm\) 0.03, respectively; \(p\)\(<\) 0.05). The Limnio grape pomace extract exhibits a notably greater concentration of total flavonoids in comparison to tahini (61.76 \(\pm\) 3.74 \(>\) 4.76 \(\pm\) 0.1; \(p\)\(<\) 0.05). The findings of this study suggest that the utilization of Limnio grape pomace and aquafaba derived from Lemnian chickpeas sourced from Panagia can be considered as suitable options for fortifying tahini. Incorporating these raw materials in small quantities can effectively enhance the overall content of total phenolics and flavonoids in tahini. The fortification of tahini with the aforementioned materials at percentages of 4% and 6% (\(w\)/\(w\)) resulted in a significant increase in the levels of total phenolics and flavonoids, with an average increase of 77.9 \(\pm\) 2.1% and 77.5 \(\pm\) 0.8%, respectively. Fortification of tahini with Limnio grape pomace extract and Lemnian chickpeas aquafaba from Panagia increased the antioxidant capacity of the fortified tahini by 100.8 \(\pm\) 0.2%, 64.6 \(\pm\) 11.1%, 77.7 \(\pm\) 7.3% and 72.9 \(\pm\) 10.1%, as was assessed by ABTS, DPPH, CUPRAC and FRAP assays, respectively. In vitro plasma oxidation was also significantly increased in fortified tahini compared to the Control by 110.2 \(\pm\) 8.3% (\(p\)\(<\) 0.05). Polyphenols are the predominant class of antioxidants found in the human diet through plant foodstuffs. At the same time, it has become widely accepted that oxidative stress is an important contributor to the onset and progression of a number of different diseases. These chemicals have distinct ways by which they exert their antioxidant capacity. The constant link between the consumption of polyphenol-rich foods and the prevention of certain chronic and degenerative diseases has led to an increase in interest in phenolic compounds. This interest has been growing steadily over the past many years. It has been demonstrated that these molecules are capable of performing a diverse range of biological tasks, such as the neutralization of free radicals, amongst others [41; 42; 43; 44]. Grape pomace is a significant reservoir of antioxidant chemicals such as phenolics that have been demonstrated to have free radical inhibitory properties in many in vitro experiments [45]. The antioxidant capacity of aquafaba has been previously discussed. There exists documented evidence suggesting that aquafaba, when discarded, contains bioactive polyphenols. Furthermore, previous studies have provided evidence that chick peas' polyphenols have the potential to leach out into the water during the boiling process, resulting in their degradation into smaller, more bioactive molecules. In the case of chickpeas' aquafaba, the process involves at least the degradation of lignin into syringe acid and the conversion of anthocyanins into 4-hydroxy benzoic acid [46; 47].