This study involves the production of short-chain organic acids from kitchen wastes as intermediates for the production of biodegradable plastics. Flasks, without mixing were used for the anaerobic conversion of the organic fraction of kitchen wastes into short-chain organic acids. The influence of pH, temperature and addition of sludge cake on the rate of organic acids production and yield were evaluated. Fermentations were carried out in an incubator at different temperatures controlled at 30 degrees C. 40 degrees C, 50 degrees C, 60 degrees C and uncontrolled at room temperature. The pH was also varied at pH 5, 6, 7, and uncontrolled pH. 1.0 M phosphate buffer was used for pH control, and 1.0 M HCl and 1.0 M NaOH were added when necessary. Sludge cake addition enhanced the rate of maximum acids production from 4 days to 1 day. The organic acids produced were maximum at pH 7 and 50 degrees C i.e., 39.84 g/l on the fourth day of fermentation with a yield of 0.87 g/g soluble COD consumed, and 0.84 g/g TVS. The main organic acid produced was lactic acid (65-85%), with small amounts of acetic (10-30%), propionic (5-10%), and butyric (5-20%) acids. The results of this study showed that kitchen wastes could be fermented to high concentration of organic acids, which could be used as substrates for the production of biodegradable plastics.
A new series of 4H-chromene-3-carboxylate derivatives were synthesized using multicomponent reaction of salicylaldehyde, ethyl acetoacetate and dimedone in ethanol with K3PO4 as a catalyst at 80 °C. The structures of all newly synthesized compounds were confirmed by spectral techniques viz. IR, 1H NMR, 13C NMR, and LCMS analysis. The newly synthesized compounds 4a to 4j were screened against elastase enzyme. Interestingly, all these compounds found to be potent elastase inhibitors with much lower IC50 value. The compound 4b was found to be most potent elastase inhibitor (IC50 = 0.41 ± 0.01 µM) amongst the synthesized series against standard Oleanolic Acid (IC50 value = 13.45 ± 0.0 µM). The Kinetics mechanism for compound 4b was analyzed by Lineweaver-Burk plots which revealed that compound inhibited elastase competitively by forming an enzyme-inhibitor complex. Along with this, all the synthesized compounds (4a - 4j) exhibits excellent DPPH free radical scavenging ability. The inhibition constant Ki for compound 4b was found to be 0.6 µM. The computational study was comprehensible with the experimental results with good docking energy values (Kcal/mol). Therefore, these molecules can be considered as promising medicinal scaffolds for the treatment of skin-related maladies.
Current study is based on the biology-oriented drug synthesis (BIODS) of 2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethyl aryl carboxylate derivatives 1-26, by treating metronidazole with different aryl and hetero-aryl carboxylic acids in the presence of 1,1'-carbonyl diimidazole (CDI) as a coupling agent. Structures of all synthetic derivatives were confirmed with the help of various spectroscopic techniques such as EI-MS, (1)H -NMR and (13)C NMR. CHN elemental analyses were also found in agreement with the calculated values. Synthetic derivatives were evaluated to check their β-glucuronidase inhibitory activity which revealed that except few derivatives, all demonstrated good inhibition in the range of IC50 = 1.20 ± 0.01-60.30 ± 1.40 μM as compared to the standard d-saccharic acid 1,4-lactone (IC50 = 48.38 ± 1.05 μM). Compounds 1, 3, 4, 6, 9-19, and 21-24 were found to be potent analogs and showed superior activity than standard. Limited structure-activity relationship is suggested that the molecules having electron withdrawing groups like NO2, F, Cl, and Br, were displayed better activity than the compounds with electron donating groups such as Me, OMe and BuO. To verify these interpretations, in silico study was also performed, a good correlation was observed between bioactivities and docking studies.