Hydrolytic nondegradable bioactive rosmarinic acid particles

Rosmarinic acid (RS) is as the nonflavonoid polyphenols in the phenolic acid subgroup was cross-linked with sodium trimetaphosphate (STMP) to obtain (p[RS-co-STMP]) particles with the size distribution of 2.992 ± 659 nm. The zeta potential values of p(RS-co-STMP) particles were measured between pH 2–10, and the isoelectric point was determined as pH 2.66. Fe(II) chelating capability test was done for RS and p(RS-co-STMP). At 800 μmol/ml concentrations, p(RS-co-STMP) particles chelated 95.06 ± 5.18% Fe(II), while RS molecule did not chelate Fe(II), whereas STMP chelated only 41.8 ± 5.9% Fe(II). The effects of RS and p(RS-co-STMP) particles on α-glucosidase enzyme activity were investigated and were found to inhibit the α-glucosidase enzyme by 55.7% and 89.6%, respectively. Furthermore, p(RS-co-STMP) particles were modified with polyethyleneimine as m-p(RS-co-STMP) to improve antimicrobial properties and found effective against both Escherichia coli and Staphylococcus aureus bacteria. The interaction of fibrinogen with RS, p(RS-co-STMP) and m-p(RS-co-STMP) were studied via the change in intensity of corresponding fluorescence spectra. It was found that p(RS-co-STMP) particles interacted lesser with fibrinogen than RS and changed the fluorescence property of fibrinogen protein slightly. On the other hand, m-p(RS-co-STMP) particles did not change the fluorescence intensity of fibrinogen suggesting no influence on the blood clotting.