Bio-inspired synthesis of flavonoids incorporated CaCO3: Influence on the phase, morphology and mechanical strength of the composites

Quercetin directed transformation of calcium carbonate into porous calcite and their application as delivery system for future foods

The hierarchically porous property of CaCO3 has attracted considerable attention in the field of active delivery ingredients due to its high adsorption capacity. Here, a facile and high-efficient approach to control the calcification processes of CaCO3 ending with calcite microparticles with superior porosity and stability is reported and evaluated. In this work, a series of quercetin promoted CaCO3 microparticles, using soy protein isolate (SPI) as entrapment agent, was synthesized, characterized, and their digestive behavior and antibacterial activity were evaluated. Results obtained indicated that quercetin showed good ability to direct the calcification pathway of amorphous calcium carbonate (ACC) with the formation of flower- and petal-like structures. The quercetin-loaded CaCO3 microparticles (QCM) had a macro-meso-micropore structure, which was identified to be the calcite form. The macro-meso-micropore structure provided QCM with the largest surface area of 78.984 m2g-1. The loading ratio of SPI to QCM was up to 200.94 μg per mg of QCM. The protein and quercetin composite microparticles (PQM) were produced by simply dissolving the CaCO3 core, and the obtained PQM was used for the delivery of quercetin and protein. Thermogravimetric analysis showed PQM presented with good thermal stability without the CaCO3 core. Furthermore, minor discrepancy was noted in protein conformational structures after removing the CaCO3 core. In vitro digestion revealed that approximately 80% of the loaded quercetin was released from PQM during intestinal digestion, and the released quercetin exhibited efficient transportation across the Caco-2 cell monolayer. More importantly, the PQM digesta retained enhanced antibacterial activities to inhibit growth of Escherichia coli and Staphylococcus aureus. Porous calcites show a high potential as a delivery system for food applications.

Properties of Air Lime Mortar with Bio-Additives

Lime mortar has been a primary binding material in ancient mortar, and is one of the main reasons behind solid and stable constructions that remain stable even after thousands of years. The benefits of lime are innumerable: it is minimally processed and used with a lesser carbon footprint and embodied energy and, most crucially, it is a carbon absorbent. This research experiments with the strength properties (compression) of lime at 28, 56, and 100 days of air curing. The investigation studies the durability using water absorption, UPV test, and carbonation parameters after 100 days of exposure to air. The tested materials are subjected to SEM analysis to find the morphology of the reaction that takes place and the products that are formed. We also performed a comparative study of two different fermented additives by the duration of fermentation (1 day and 10 days) and two different doses of additives (Jaggery and Kadukkai) with air lime. The bio-additives were experimented with using gas chromatography and mass spectroscopy for the formation of new enriching compounds, which improved the qualities of traditional lime mortar. The formation of fat and protein in the additives was found using IS 7219-1973 (a method for the determination of protein in foods and feeds). Using the AOAC method, the presence of fat confirms the improvement in strength and durability properties. The phytochemical analysis details the alkaloids, terpenoids, steroids, phenols, flavonoids, tannins, glycosides, and saponins. Quantification of phenols and flavonoids adds to the beneficial aspects of the fermented additives. The experimental results indicate that using naturally fermented organic materials in the lime has made the structures stronger with the stable build of calcite and vaterite components. The self-healing capacity of lime mortar makes it time resistant.