## 3 Results and Discussion
### Antioxidant Activity  
The antioxidant activity of the hawthorn extracts was determined using DPPH and FRAP assays. The FRAP of the sample treated with the _R. miehei_ cellulase cocktail improved significantly (\(p<0.05\)), presenting an increment of about 1.7-fold after incubation compared to enzyme-free extraction (Figure 4A). An increase (1.15-fold) (\(p<0.05\)) was also found in the DPPH scavenging activity when the residues were treated with the _R. miehei_ enzyme compared to acetate buffer extraction (Figure 4B). The DPPH radical scavenging activity achieved for the hawthorn extracts (Figure 4B) corresponds to those shown by about 6 uM of gallic acid, catechin, and quercetin or about 32 uM of ascorbic acid in the work of [PERSON] et al. [36]. In addition, the radical scavenging activity exhibited by the extracts (25-30%, Figure 4B) makes them suitable antioxidants in interaction tests [36]. Correlation analysis revealed a strong association between TPC and DPPH inhibition (r = 0.964), as well as FRAP (r = 0.981), suggesting that the phenolics released during enzyme treatments have an important role in the antioxidant activity increase of extracts. A significant positive relationship was also observed between FRAP and DPPH (r = 0.997). Positive relationships between antioxidant activity and phenolic content of extracts have been described in hawthorn [37; 38; 39], sorghum [30; 40], chestnut [41], and tea [42] samples as well. It should be noted that even if the measured TPC was increased by adding pectinose to the _R. miehei_ enzyme cocktail, the antioxidant capacity was not significantly altered (\(p>0.05\)). It is known that the Folin reagent used frequently in TPC measurements is not specific only to phenolics. Other hydroxyl group-bearing compounds, such as reducing sugars, ascorbic acid, tryptophan, and others, can also reduce the reagent [43]. The reducing sugars released from the pectin chain by pectinose hydrolysis may be responsible for the increased Folin reactivity, but these compounds do not contribute to the increase in antioxidant capacity. The antioxidant activity of various hawthorn extracts has already been published in the literature. For comparison, the level of FRAP was found between 0.34 and 1.84 mmol Fe (II)/g dry weight for fruits of different hawthorn species, including _C. orientalis_, with a value of 0.45 mmol Fe (II)/g dry weight [5]. In _Crataegus monogyna_, the extract of ripened fruits showed an inhibition of about 83% against DPPH radicals, while the inhibitory  
Figure 4: FRAP activity (**A**) and DPPH radical scavenging capacity (**B**) of hawthorn fruit extracts prepared by acetate buffer (C), cellulase (S1), and cellulase–pectinase (S2) extractions. The values shown are averages of the data obtained from three measurements; error bars represent the standard deviation. The different letters above the columns indicate significant differences according to one-way ANOVA followed by [PERSON]’s multiple comparison test (\(p<0.05\)). effect was about 89% for the unripe fruits [37]. [PERSON] et al. [39] quantified a 21.4% DPPH inhibitory effect in the methanolic extract of _C. orientalis_ var. _orientalis_. The _C. orientalis_ extract, which also originated from Turkey, demonstrated a DPPH inhibition of 1567.39 half-maximal effective concentration (EC\({}_{50}\)) in ug/mL equivalents and a FRAP of 0.73 mM FeSO\({}_{4}\)/g dried extract in the work of [PERSON] et al. [38]; the FRAP value was slightly lower to that determined for _C. monogyna_ collected from the same geographical area [38]. _C. oxycamatha_ extracts produced by [PERSON] et al. [3] had a percent DPPH inhibitory action between 60.61% and 89.89% depending on the extraction methodology. Although these samples were made via methanol/ethanol-based solvent extraction approaches, antioxidant activity data achieved here with enzyme-assisted extractions proved to also be considerable.