Electrochemical Iodination through the In Situ Generation of Iodinating Agents: A Promising Green Approach.

The synthesis of iodinated compounds using cheap, simple, and green strategies is of fundamental importance. Iodination reactions are mainly used to synthesize useful intermediates, especially in the pharmaceutical field, where they are employed for the production of contrast media or of iodinated active pharmaceutical ingredients. Traditional synthetic methods suffer from the use of erosive, toxic, or hazardous reactants. Approaches which involve the use of molecular iodine as an iodinating agent require the addition of an oxidizing agent, which is often difficult to handle. Electrochemistry can offer a valid and green alternative by avoiding the addition of such oxidizing agents, transforming the iodine source in the active species through the use of electrons as the main reactants. Herein, we report the electrochemical iodination with the generation of iodinating species in situ in water by using iodides as the source of iodine atoms. First of all, the electrochemical behavior of iodide and iodine in water on carbonaceous anodes was studied and, after selecting the suitable potential, in situ electrochemical iodination was successfully applied to 5-hydroxyisophthalic acid and 5-sulfosalicylic acid, comparing the iodinating power of I2 and iodonium species.

Taste Compounds and Polyphenolic Profile of Tomato Varieties Cultivated with Beneficial Microorganisms: A Chemical Investigation on Nutritional Properties and Sensory Qualities.

There is a strong need to develop eco-sustainable agricultural techniques to improve crop yields while preserving biomolecule contents and reducing the adverse environmental impact of agro-chemicals. The use of microorganisms in agriculture represents an attractive and innovative solution. Herein, a chemical study on the nutritional and sensory qualities of San Marzano Cirio 3 (SMC3), Corbarino (CO) and Brandywine (BW) tomato varieties cultivated with and without effective microorganisms (EM) is reported. LC-MS analysis of the methanolic extracts allowed for the identification of 21 polyphenol derivatives. In different proportions among the studied varieties, the two main polyphenols were rutin and naringenin chalcone; the latter was isolated and chemically identified by complementary HR-ESIMS/MS and NMR methods. SMC3 and CO were richer in naringenin chalcone. Conversely, BW showed higher proportions of rutin; however, in all cases, the relative amounts of the two polyphenols considered together increased over the other minor components after the EM treatment. The qualitative and quantitative HPLC analyses of taste-active compounds (aspartic acid, glutamic acid, AMP and GMP) revealed a significant difference in aspartic and glutamic acids and ribonucleotide contents according to the cultivation condition (±EM), particularly in BW. This study provides chemical data in support of the use of EM green technology for the cultivation of edible agricultural products, such as tomato preserves, and may even improve nutritional and sensory qualities while safeguarding the environment.

Impact of drying techniques, seasonal variation and organic growing on flavor compounds profiles in two Italian tomato varieties.

The industrial transformation of tomato (Lycopersicon esculentum Mill.) produces processed foods, such as dried tomatoes. In this study two varieties (SaAb and PerBruzzo), grown in three cropping systems (one conventional and two organic ones), were processed by two types of small-scale drying (oven or sun drying), over two years of production. The dried samples were analyzed for their non-volatile and volatile composition, relating the results with sensory analysis. The multivariate analysis performed on collected data allowed a detailed comparison of the effects of processing, year-to year variation and cropping systems. Results indicated that drying methods mainly influenced the composition and flavor profile, also affected by the production year. The cropping system significantly influenced some quality indices, such as the acid and sugar amounts, and the aldehydes, respectively higher and lower in organic samples. The comprehensive PCA analysis allowed discrimination of drying methods and, to a lesser extent, cropping systems.