Multivariate chemometric analysis for the evaluation of 22 Citrus fruits growing in Brazil's semi-arid region

This work provides the first screening of 22 Citrus cultivars grown in a semi-arid tropical region based on their most relevant phytochemical and polyphenolic features through a multivariate approach. Multivariate chemometric analysis through PCA analysis were used combined to reach grouping of the Citrus fruits and unveil the main characteristics associated with the fruits identity and origin region. Citric acid was the dominant organic acid (4.43-140.54 g L-1), representing 93.9 % of total organic acids quantified in the samples. Glucose and fructose corresponded, respectively, to 51.2 and 48.8 % of the total sugars quantified in samples. Hesperidin was the predominant flavonoid identified in all Citrus, particularly in oranges, while in pomelos, naringin was the major polyphenol. The results showed that most phenolics are related to Citrus identity, as PCA revealed the grouping of samples according to the species or variety. The associations found for the Citrus obtained from the same semi-arid tropical location could be used as basis for authentication of these Citrus samples, as judged by the distinctions found between the phenolic profiles, sugars and organic acids. This could be used for other fruits upon verification of their polyphenolic association with location and climate.

Automated summary

This study conducted the first screening of 22 Citrus cultivars in a semi-arid tropical region based on their phytochemical and polyphenolic features, using multivariate chemometric analysis. The results showed that citric acid was the dominant organic acid, glucose and fructose were the major sugars, hesperidin was the predominant flavonoid in all Citrus, and naringin was the major polyphenol in pomelos. The findings suggest that phenolic profiles can be used for authentication of Citrus samples based on their origin and can potentially be applied to other fruits as well.