In vitro Assessment of Chemical and Pre-biotic Properties of Carboxymethylated Polysaccharides From Passiflora edulis Peel, Xylan, and Citrus Pectin

This study aimed to determine the carboxymethylation effect of crude water-soluble polysaccharides of Passiflora edulis peel (WPEP), xylan (XY), and citrus pectin (CP). Their chemical and pre-biotic properties were also determined. The polysaccharides were carboxymethylated by reacting with chloroacetic acid and sodium hydroxide. The carboxymethylated and non-carboxymethylated polysaccharides were also used as pre-biotics to study the growth pattern of selected intestinal microflora. These polysaccharides substituted the glucose solution in culture media for culturing Lactobacillus brevis GIM1.773, Lactobacillus plantarum GIM1.19, Lactobacillus delbrueckii subsp. bulgaricus GIM1.155, and Streptococcus thermophilus GIM1.540. The results showed that the carboxymethylated polysaccharides c-XY, c-CP, and c-WPEP, had substitution degrees of 0.682, 0.437, and 0.439, respectively. The polysaccharides demonstrated resistance to digestion in the simulated human digestive models. The resistance to digestion was enhanced by carboxymethylation, especially the carboxymethylated CP and WPEP. The results also showed that the pre-biotic activities of the polysaccharides increased after carboxymethylation. The c-XY had a better pre-biotic effect than XY and the other carbohydrate samples. The findings suggested that carboxymethylated polysaccharides may be developed into novel pre-biotics and nutraceuticals that could promote growth of the probiotic strains.

Acid Treated Montmorillonite—Eco-Friendly Clay as Catalyst in Carvone Isomerization to Carvacrol

Acid-treated montmorillonites (MMT) were used as catalysts of carvone isomerization to carvacrol. Mineral acids—sulfuric, hydrochloric, nitric acids and organic acids (acetic and chloroacetic)—were used for the acid treatment. Prepared materials were characterized by available characterization methods, namely XRD, EA, TPD, TPO, UV-Vis, laser light scattering and nitrogen physisorption. The structure of montmorillonite remained intact after treatment. However, TPD proved the increase of acidity of acid-treated materials comparing pure montmorillonite. All materials were tested in the isomerization of carvone, producing carvacrol as the desired product. The initial reaction rate increased using the materials in the row MMT-COOH < MMT-HNO3 < MMT-ClCOOH < MMT-H2SO4 < MMT-HCl, which is in accordance with the pKa of acids used for the treatment. The number of weak acid sites strongly influenced the selectivity to carvacrol. The optimal solvent for the reaction was toluene. Total conversion of carvone and the selectivity to carvacrol 95.5% was achieved within 24 h under 80 °C, with toluene as solvent and montmorillonite treated by chloroacetic acid as catalyst. The catalyst may be reused after calcination with only a low loss of activity.

Synthesis and Pharmacological Evaluation of Novel 2,3,4,5-tetrahydro[1,3]diazepino[1,2-a]benzimidazole Derivatives as Promising Anxiolytic and Analgesic Agents

A number of novel 2,3,4,5-tetrahydro[1,3]diazepino[1,2-a]benzimidazole derivatives 2 were obtained by alkylation mainly in the 1H-tautomeric form of 2,3,4,5-tetrahydro[1,3]diazepino[1,2-a]benzimidazole or its 8,9-dimethyl-substituted analog 4-chlorobenzyl bromide, 4-chloroacetic acid fluoroanilide, and 4-tert-butylphenacyl bromide in neutral medium. Compounds 3 were cyclized and synthesized earlier with 11-phenacyl-substituted diazepino[1,2-a]benzimidazoles upon heating in conc. HBr. The chemical structures of the compounds were clarified by using the 1H Nuclear Magnetic Resonance Spectroscopy (1H-NMR) technique. Anxiolytic properties were evaluated using the elevated plus maze (EPM) and open field (OF) tests. The analgesic effect of compounds was estimated with the tail flick (TF) and hot plate (HP) methods. Besides, possible the influence of the test compounds on motor activities of the animals was examined by the Grid, Wire, and Rotarod tests. Compounds 2d and 3b were the most active due to their prominent analgesic and anxiolytic potentials, respectively. The results of the performed in silico analysis showed that the high anxiolytic activity of compound 3b is explained by the combination of a pronounced interaction mainly with the benzodiazepine site of the GABAA receptor with a prominent interaction with both the specific and allosteric sites of the 5-HT2A receptor.

Production of Functional Buttermilk and Soymilk Using Pediococcus acidilactici BD16 (alaD+)

Functional foods or drinks prepared using lactic acid bacteria (LAB) have recently gained considerable attention because they can offer additional nutritional and health benefits. The present study aimed to develop functional drinks by the fermentation of buttermilk and soymilk preparations using the Pediococcus acidilactici BD16 (alaD+) strain expressing the L-alanine dehydrogenase enzyme. LAB fermentation was carried out for 24 h and its impact on the physicochemical and quality attributes of the fermented drinks was evaluated. Levels of total antioxidants, phenolics, flavonoids, and especially L-alanine enhanced significantly after LAB fermentation. Further, GC-MS-based metabolomic fingerprinting was performed to identify the presence of bioactive metabolites such as 1,2-benzenedicarboxylic acid, 1-dodecene, 2-aminononadecane, 3-octadecene, 4-octen-3-one, acetic acid, azanonane, benzaldehyde, benzoic acid, chloroacetic acid, colchicine, heptadecanenitrile, hexadecanal, quercetin, and triacontane, which could be accountable for the improvement of organoleptic attributes and health benefits of the drinks. Meanwhile, the levels of certain undesirable metabolites such as 1-pentadecene, 2-bromopropionic acid, 8-heptadecene, formic acid, and propionic acid, which impart bitterness, rancidity, and unpleasant odor to the fermented drinks, were reduced considerably after LAB fermentation. This study is probably the first of its kind that highlights the application of P. acidilactici BD16 (alaD+) as a starter culture candidate for the production of functional buttermilk and soymilk.

Synthesis, Characterization of Thiazolidin-4-one, Oxazolidin-4-one and Imidazolidin-4-one Derivatives from 6-Amino-1,3-dimethyluracil and evaluation of their Antioxidant and Antimicrobial Agent

In this study, a new series of 6-amino-1,3-dimethyluracil derivative with 6-(3-substituted N-benzylidene)-1,3-dimethyl pyrimidine-2,4-dione-6-yl derivatives which were synthesized by using one pot synthesis. The reaction of 6-amino-1,3-dimethyluracil and different aromatic aldehyde in ethanol yielded Schiff bases (1-6). In the subsequent step reaction of Schiff bases )1-6) with 2-mercaptoacetic acid, 2-chloroacetic acid and 2-amino acetic acidn in Tetrahydrofuran yielded five membered heterocyclic rings of 6-amino-1,3-dimethyluracil derivative which includes: 2,3-thiazolidin-4-one (7-12), 2,3-oxazolidin-5-one (13-18), 2,3-imidazolidin-4-one (19-24) derivatives. The structures of newly synthesized compounds were confirmed by their physicochemical and spectral means FTIR, 1HNMR and 13CNMR. The synthesized compounds were evaluated in vitro for antioxidant and antimicrobial activities against four types of bacteria and four types of fungi