ATR–FTIR Spectroscopy Combined with the Invitro Antioxidant Activity and Chromaticity for Rapid Discrimination of Fig (Ficus carica L.) Cultivars

FTIR spectroscopy-based lipochemical fingerprints involved in pomegranate response to water stress

Pomegranate trees are known for their ability to withstand drought conditions, but there is still much to learn about how water stress affects the lipobiochemical behavior of their seeds. This study aimed to investigate how sustained deficit irrigation (SDI-50), equivalent to 50% of crop evapotranspiration, influences pomegranate seed oil attributes such as phenols, flavonoids, and tannins content, and the seeds' lipochemical fingerprints compared to fully irrigated trees. At the full ripening stage, pomegranate seeds were analyzed for their oil content, biochemical traits, and vibrational fingerprints using infrared radiation. The results indicated that there was a significant genotypic effect coupled with applied water stress on all the investigated traits. Interestingly, an increasing trend in seed oil yield was observed under water stress conditions compared to the control, with the highest oil yield increase observed in the 'Zheri Precoce' fruit seeds. Only two cultivars did not show the same pattern, with the oil yield increase ranging from 8% to 100%. Furthermore, SDI-50 induced a substantial increase in total phenolic content, coupled with a significant genotypic effect, and resulted in an average increase of 7.5%. This increase in total phenolics also correlated with an increase in antioxidant activity across all investigated cultivars. ATR-FTIR fingerprinting revealed eleven spectral fingerprints corresponding to functional groups present in pomegranate seeds oil, with a particular pattern of significant effects of both genotypic and SDI-50 factors. These results suggest that exploiting water scarcity conditions could be a viable approach to improve the quantitative and qualitative attributes of pomegranate seed oil. While there are still several aspects to be investigated further, this study provides a basis for pomegranate processing under water shortage conditions.

Very rapid synthesis of highly efficient and biocompatible Ag2Se QD phytocatalysts using ultrasonic irradiation for aqueous/sustainable reduction of toxic nitroarenes to anilines with excellent yield/selectivity at room temperature

There are many problems associated with the synthesis of nanocatalysts and catalytic reduction of nitroarenes - e.g., high temperatures, costs, long reaction/synthesis process times, the toxicity of chemicals/solvents, undesirable byproducts, the toxic/harmful wastes, low efficiency/selectivity, etc. This study represents an attempt to overcome these challenges. To this purpose, biocompatible and highly efficient Ag₂Se quantum dots (QDs) catalysts with antibacterial activity were synthesized in a very rapid (30 sec, rt), simple, inexpensive, sustainable/green, and one-pot strategy in water using ultrasonic irradiation. Characterization of the QDs was performed using different techniques. UV-Vis absorption and fluorescence spectroscopic studies showed an absorption peak at 480-550 nm and a maximum emission peak around 675 nm, which confirmed the successful synthesis of Ag₂Se QDs via the applied biosynthetic method. Subsequently, catalytic reduction of nitroarenes by them was carried out under safe conditions (H₂O, rt, air atmosphere) in ∼ 60 min with excellent yield and selectivity (>99%). Their catalytic activity in the reduction of various toxic nitroarenes to aminoarenes under green conditions was investigated. Thus, a rapid and safe ultrasound-based method was employed to prepare stable and green Ag₂Se QDs phyto-catalysts with unique properties, including exquisite monodispersity in shape (orthorhombic) and size (∼7 nm), air-stability, and good purity and crystallinity. Importantly, instead of various toxic chemicals, the plant extract obtained by rapid ultrasonic method (10 min, rt) was used as natural reducing, capping, and stabilizing agents. Moreover, antibacterial assays results showed that Ag₂Se-QDs catalysts at low concentrations (ppm) have high activity against all tested bacteria, especially E. coli (MIC:31.25 ppm, MBC:125 ppm) which were significantly different from those of Fig extract (MIC = MBC:500 ppm). The data reflect the role of these bio-synthesized Ag₂Se-QDs catalysts in the development of versatile and very safe catalysts with biomedical properties.