Do Pollination and Pollen Sources Affect Fig Seed Set and Quality? First Attempt Using Chemical and Vibrational Fingerprints Coupled with Chemometrics

Abstract

This research investigates whether pollination and pollen sources separately and simultaneously influence fig seed set and quality, as being thus far the less studied part of the fig trees. This is the first research that tries to answer and verify the above hypothesis through a combined approach of vibrational spectroscopy along with lipo-biochemical and ionomic fingerprinting. Results showed that pollination and pollen source significantly impacted seed set as it was higher in fertilized seeds than that in the control. A similar pattern was obtained with oil yield, which generally ranged between 25.93 and 32.59%. Caprification also displayed a substantial effect on seeds' phenolic components, which was more driven by pollen carbohydrates, involved in the phenolic biosynthesis in the endosperm and embryo tissues. This biosynthesis is also activated by minerals, which are cofactors for large varieties of enzymes that are involved in the phenolic synthesis pathways. Ca and Zn did not follow this pattern and have recorded high levels in figs fertilized by the pollen of OZ and FD4 caprifigs pollen, respectively. Vibrational spectroscopy using Fourier transform infrared (FTIR) spectroscopy coupled with total attenuated reflectance (ATR) also showed a similar pattern to the seed sets and their lipo-biochemical attributes. Thus, the fertilized seeds displayed high vibrational intensity compared to the control in all fingerprint regions. Peaks at 2928 and 1747 cm−1 had a higher intensity and were attributed to lipids CH2 and CH3 stretching vibration and C=O of the carbonyl groups belonging to the triacylglycerols, respectively. Principal component analysis showed high throughput classification with quite similar patterns for both FTIR-ATR fingerprinting and ionomic and biochemical analysis. As many areas of how caprification impacts other seed aspects still need to be investigated further, this research suggests the importance of caprification in seed valorization for oil extraction and as a functional ingredient.

Bioactive Compounds, Functional Ingredients, Antioxidants, and Health Benefits of Edible Plants

“…Richness of fig seeds in proteins and mineral elements has already been reported (Duman et al, 2018;Nakilcioglu-Tas, 2019;Bölek, 2020); also, the effect of pollination on their content (Hssaini et al, 2022). Ustun-Argon et al (2021) report that Potassium, Magnesium and Calcium were the main mineral compounds in the dried fig seeds.…”

“…These seeds, which vary in number and size, play a crucial role in determining the flavor and taste of figs, as well as their nutritional composition. These aspects are influenced by several factors, including the genotype of the fig, its ripening stage, and the mutualistic relationship between the fig and its pollinator wasp, which is known as caprification (Solomon et al, 2006;Gaaliche et al, 2011;Rosianski et al, 2016;Hssaini et al, 2022). Despite their contribution to the nutritional composition of figs, there have been very few studies on fig seeds (Hssaini et al, 2020;Hssaini et al, 2021a).…”

“…Previous research has shown that fig seed oil is generally pale yellow in color and yields can vary significantly based on the genotype, with some genotypes yielding up to 30% oil content (Hssaini et al, 2020). The macro-qualitative components of fig seeds, including oil yield and lipochemical composition, are influenced by both genetic differences between seeds and geographical variations (Raihana et al, 2015;Górnaśand Rudzińska, 2016) as well as the pollination system (Hssaini et al, 2022). Compared to other fruit seeds, fig seeds have an oil yield that is similar to pumpkin (27.83%) (Alfawaz, 2004), honeydew (25%) (Yanty et al, 2008), and mangosteen (21.18%) (Ajayi et al, 2007), and higher than those of durian seeds (1.8%) (Berry, 1980), Opuntia ficus indica seeds (5.4 to 9.9%) (Taoufik et al, 2015), and guava (16%) (Prasad and Azeemoddin, 1994).…”

Lipidomic profiling reveals phenotypic diversity and nutritional benefits in Ficus carica L. (Fig.) seed cultivars

“…These seeds, which vary in number and size, play a crucial role in determining the flavor and taste of figs, as well as their nutritional composition. These aspects are influenced by several factors, including the genotype of the fig, its ripening stage, and the mutualistic relationship between the fig and its pollinator wasp, which is known as caprification (Solomon et al, 2006;Gaaliche et al, 2011;Rosianski et al, 2016;Hssaini et al, 2022). Despite their contribution to the nutritional composition of figs, there have been very few studies on fig seeds (Hssaini et al, 2020;Hssaini et al, 2021a).…”

“…Previous research has shown that fig seed oil is generally pale yellow in color and yields can vary significantly based on the genotype, with some genotypes yielding up to 30% oil content (Hssaini et al, 2020). The macro-qualitative components of fig seeds, including oil yield and lipochemical composition, are influenced by both genetic differences between seeds and geographical variations (Raihana et al, 2015;Górnaśand Rudzińska, 2016) as well as the pollination system (Hssaini et al, 2022). Compared to other fruit seeds, fig seeds have an oil yield that is similar to pumpkin (27.83%) (Alfawaz, 2004), honeydew (25%) (Yanty et al, 2008), and mangosteen (21.18%) (Ajayi et al, 2007), and higher than those of durian seeds (1.8%) (Berry, 1980), Opuntia ficus indica seeds (5.4 to 9.9%) (Taoufik et al, 2015), and guava (16%) (Prasad and Azeemoddin, 1994).…”