# The Infestation of Olive Fruits by _Bactrocera oleae_ ([PERSON])
## 2 Results and Discussion
### Effect of Bactrocera oleae Infestation on the Phenolic Profile of VOO  
Figure 3 shows the content of the main groups of phenolic compounds in the oils obtained from non-infested (control) and _B. oleae_-infested fruits. Comparison of the phenolic composition of the control oils of the cultivars under study reveals evident cultivar differences according to the high variability of olive in terms of phenolic composition [34]. Among the cultivars analyzed in this study, cv. Hojiblanca showed the lowest phenolic content, while cv. Manzanilla exhibited the highest phenolic content, above 400 mg g\({}^{-1}\) oil (Table 1). The most abundant compound in the three olive cultivars was 3,A-DHPEA-EA, which is associated with the bitter taste notes of VOO [35]. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Compounds (mg/g Oil)** & \multicolumn{2}{c}{**-**} & & & & \\ \hline  & Picusal-C & Picusal-I & Manz-C & Manz-I & Hojib-C & Hojib-I \\ \hline Hydroxytyrosol & 0.6b * & 0.2a & 1.6b & 0.3b & 1.9b & 0.4a \\ Tyrosoll & 1.9b & 0.4a & 4.3b & 0.8b & 3.0b & 0.7a \\ Vanillic acid & 0.2b & 0.1a & 0.2b & 0.1b & 0.4b & 0.1a \\ vanillin & 0.1a & 0.1a & 0.1a & 0.1b & 0.2b & 0.1a \\ p-coumaric acid & 0.3a & 0.5b & 0.2a & 0.1b & 0.6b & 0.2a \\ Hydroxytyrosol ac. & 2.7a & 5.9b & 7.3a & 13.7b & 1.8a & 2.6b \\
3,4-DHPEA-EDA & 24.8a & 28.7a & 121.0b & 96.7a & 24.3a & 24.9a \\ p-HPEA-EDA & 22.7a & 41.9b & 44.5a & 64.2b & 3.6a & 3.5a \\ Pinoresinol & 3.2b & 1.1a & 2.2b & 1.2b & 1.6b & 1.5a \\ Cinamamic acid & 1.1b & 0.1a & 0.9b & 0.1b & 0.4b & 0.2a \\ Acetoxipinoiresinol & 11.0b & 1.5a & 12.3b & 3.3b & 17.7b & 4.9a \\
3,4-DHPEA-EA & 135.6b & 14.7a & 196.3b & 48.1b & 31.8b & 9.7a \\ p-HPEA-EA & 13.3b & 9.9a & 16.9b & 12.6b & 12.9b & 10.6a \\ Ferulic acid & 0.2b & 0.1a & 0.2b & 0.1b & 0.0 & 0.0a \\ Luteolin & 4.8b & 0.7a & 5.4b & 0.6b & 12.7b & 1.4a \\ Apigenin & 0.9b & 0.1a & 0.9b & 0.2b & 2.2b & 0.3a \\ Total phenolics & 223.3b & 106.1a & 414.4b & 242.1b & 115.2b & 61.2a \\ o-diphenylics & 168.5b & 50.2a & 331.6b & 159.5b & 72.5b & 39.0a \\ Secoiridoids & 196.3b & 95.2a & 378.7b & 221.6b & 72.7b & 48.8a \\ \hline \hline \end{tabular} (*) Different letters indicate statistically significant differences according to [PERSON]’s test (\(p\leq 0.05\)).  
\end{table} 
Table 1: Phenolic compounds analyzed in virgin olive oils obtained from non-infested (C) and infested (I) olive fruits (cvs. Picusal, Manzanilla, and Hojiblanca). Figure 3: Content (ug g\({}^{-1}\) oil) of the main groups of phenolic compounds in oils extracted from non-infested (C) and infested (I) olive fruits (cvs. Picusal, Manzanilla, and Hojiblanca). Data are mean contents from three different analyses. Despite the singularities of each cultivar, the total phenolic content was reduced by around 50% in the oils obtained from olive fruits infested with _B. oleae_. Although no conclusive results were found in some previous studies on the effect of _B. oleae_ infestation on the VOO phenolic profile due to the great variability in the phenolic composition associated to other factors such as olive cultivar, growing practices, or extraction methods [36], significant correlations have been reported by some authors [37]. Thus, [PERSON] et al. [33] found a negative linear correlation between the total phenolic content of oils from autochthonous Istrian olive cultivars and the infestation level of the fruits. Similar results were recently reported by [PERSON] et al. [38] when comparing the effect of active and damaging infestation in _cv._ Istrska belica fruits affected by _B. oleae_. These authors found very significant decreases in hydroxytyrosol derived compounds as did [PERSON] et al. in cv. Franttoio fruits with different degrees of damage [39]. Similarly, we have observed that the contents of hydroxytyrosol derivatives are those that experience the greatest decreases as a consequence of _B. oleae_ infestation (Table 1), the decrease of 3,4-DHPEA-EA being especially notable, with reductions of 90%, 75%, and 70% in cvs. Picual, Manzanilla, and Hojibalca, respectively.