Inhibition of Staphylococcus aureus and Pseudomonas aeruginosa Biofilm and Virulence by Active Fraction of Syzygium cumini (L.) Skeels Leaf Extract: In-Vitro and In Silico Studies.

Syzygium cumini L. Skeels (Myretacae family) is a native plant of the Indian subcontinent which has wide socio-economical importance and is well known for its ant diabetic activity. The present study aimed to investigate the antibiofilm activity of purified fraction (EA) from S. cumini leaf extract against P. aeruginosa and S. aureus. The EA did not show any effect on growth of P. aeruginosa and S. aureus at the concentration of 900 µg/ml. At this concentration EA showed biofilm inhibition up to 86 ± 1.19% (***P < 0.0001) and 86.40 ± 1.19% (***P < 0.0001) in P. aeruginosa and S. aureus respectively. SEM examination also confirmed the reduction in biofilm formation. Further EA also disrupted some virulence phenotypes in P. aeruginosa and S. aureus. Bioactive compounds detected by GC-MS showed their possible molecular interaction with RhlG/NADP active-site complex (PDB ID: 2B4Q), LasR-TP4 complex (PDB ID: 3JPU) and Pseudaminidase (PDB ID: 2W38) from P. aeruginosa. The in vitro biofilm inhibition, virulence factor inhibition and the mode of interaction of bioactive components in Syzygium cumini with QS proteins of bacteria reported in this study might be an affordable and effective alternative method of controlling quorum sensing/biofilm-associated infections.

Hypocholesterolemic activity of indigenous probiotic isolate Saccharomyces cerevisiae ARDMC1 in a rat model.

The aim of this study was to investigate probiotic attributes of Saccharomyces cerevisiae ARDMC1 isolated from traditional rice beer starter cake and its hypocholesterolemic effects on Wistar rats fed a high-cholesterol diet. The indigenous isolate ARDMC1 showed potential probiotic characteristics such as tolerance to simulated gastrointestinal stress conditions, autoaggregation properties, and adhesion to intestinal epithelium Caco-2 cell line. In addition, ARDMC1 isolate exhibited in vitro cholesterol assimilation properties in media supplemented with cholesterol. Furthermore, administration of probiotic isolate to rats fed a hypercholesterolemic diet resulted in significant reduction of serum total cholesterol, low-density lipoprotein cholesterol, and triglyceride at the end of 42 days. The present study envisages ARDMC1 as a promising starter culture for the preparation of functional foods with properties to combat cardiovascular diseases.

Effect of maleylation on physicochemical and functional properties of rapeseed protein isolate.

Influence of maleylation on the physicochemical and functional properties of rapeseed protein isolate was studied. Acylation increased whiteness value and dissociation of proteins, but reduced free sulfhydryl and disulfide content (p < 0.05). Intrinsic fluorescence emission and FTIR spectra revealed distinct perturbations in maleylated proteins' tertiary and secondary conformations. Increase in surface hydrophobicity, foaming capacity, emulsion stability, protein surface load at oil-water interface and decrease in surface tension at air-water interface, occurred till moderate level of modification. While maleylation impaired foam stability, protein solubility and emulsion capacity were markedly ameliorated (p < 0.05), which are concomitant with decreased droplet size distribution (d 32). In-vitro digestibility and cytotoxicity tests suggested no severe ill-effects of modified proteins, especially up to low degrees of maleylation. The study shows good potential for maleylated rapeseed proteins as functional food ingredient.

Antioxidative, hemocompatible, fluorescent carbon nanodots from an "end-of-pipe" agricultural waste: exploring its new horizon in the food-packaging domain.

The attention of researchers is burgeoning toward oilseed press-cake valorization for its high protein content. Protein removal from oil-cakes generates large quantities of fibrous residue (oil-and-protein spent meal) as a byproduct, which currently has very limited practical utility. In the wake of increasing awareness in waste recycling, a simple environmentally benign hydrothermal carbonization process to convert this "end-of-pipe" waste (spent meal) into antioxidative, hemocompatible, fluorescent carbonaceous nanoparticles (FCDs) has been described. In the present investigation, an interesting application of FCDs in fabricating low-cost rapeseed protein-based fluorescent film, with improved antioxidant potential (17.5-19.3-fold) and thermal stability has been demonstrated. The nanocomposite film could also be used as forgery-proof packaging due to its photoluminescence property. For assessing the feasibility of antioxidative FCDs in real food systems, a comparative investigation was further undertaken to examine the effect of such nanocarbon-loaded composite film on the oxidative shelf life of rapeseed oil. Oil samples packed in nanocomposite film sachets showed significant delay in oxidative rancidity compared to those packed in pristine protein-film sachet (free fatty acids, peroxide value, and thiobarbituric acid-reactive substances reduced up to 1.4-, 2-, and 1.2-fold, respectively). The work presents a new concept of biobased fluorescent packaging and avenues for harnessing this potent waste.

Removing antinutrients from rapeseed press-cake and their benevolent role in waste cooking oil-derived biodiesel: conjoining the valorization of two disparate industrial wastes.

Valorization of oilseed processing wastes is thwarted due to the presence of several antinutritional factors such as phenolics, tannins, glucosinolates, allyl isothiocyanates, and phytates; moreover, literature reporting on their simultaneous extraction and subsequent practical application is scanty. Different solvent mixtures containing acetone or methanol pure or combined with water or an acid (hydrochloric, acetic, perchloric, trichloroacetic, phosphoric) were tested for their efficiency for extraction of these antinutritive compounds from rapeseed press-cake. Acidified extraction mixtures (nonaqueous) were found to be superior to the nonacidified ones. The characteristic differences in the efficacy of these wide varieties of solvents were studied by principal component analysis, on the basis of which the mixture 0.2% perchloric acid in methanol/acetone (1:1 v/v) was deemed as "the best" for detoxification of rapeseed meal. Despite its high reductive potential, hemolytic activity of the extract from this solvent mixture clearly indicated the toxicity of the above-mentioned compounds on mammalian erythrocytes. Because of the presence of a high amount of antinutritive antioxidants, the study was further extended to examine the influence of this solvent extract on the stability of waste cooking oil-derived biodiesel. Treatment with the extract harbored significant improvement (p < 0.05) in the induction periods and pronounced reduction in microbial load of stored biodiesel investigated herein. Thus, a suitable solvent system was devised for removing the major antinutrients from rapeseed press-cake, and the solvent extract can, thereafter, be used as an effective exogenous antioxidant for biodiesel. In other words, integrated valorization of two different industrial wastes was successfully achieved.