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Considering the high biodiversity of microalgae and their important impact on economy and ecological balance, new screening techniques are needed for their phenotypic characterization and efficient valorization of bioactive components. This represents one the key purpose of the emerging bioeconomy concept, involving new biorefinery technologies coupled with advanced analytical tools. The article presents an overview of the recent extraction and chemical techniques used to recover, separate and characterize the main bioactive molecules (lipids and fatty acids, carbohydrates, proteins and mycosporine-like amino acids chlorophylls and carotenoid pigments) syntesized by microalgae, considering their interesting applications in food, pharmaceutical and cosmetic industries. Special focuses will be directed towards the cell disintegration and extraction procedures, identification and quantification of main metabolites by advanced analytical techniques. [ABSTRACT FROM AUTHOR]

Introduction: Although obesity and its biomarkers have been intensively studied, little is known about the metabolomic signature of visceral adiposity independent of insulin resistance that frequently accompanies increased levels of visceral fat. Our study aimed to investigate specific changes in amino acid (AA) levels as biomarkers of increased visceral adiposity independent of insulin resistance, in healthy subjects.

The aim of the present study was to create a functional, enriched in polyphenols and free of alcohol product obtained by acetic fermentation of beer. Beer and vinegar were tested first for their phenolic content and antioxidant activity, by the Folin Ciocalteu and the free radical scavenging activity by the 1,1-diphenyl-2-picrylhydrazyl free-radical scavenging assay, respectively. Then, the separation and identification of the 30 phenolic compounds was realized by high-performance liquid chromatography coupled with positive electrospray ionisation and diode array detection (HPLC-DAD–ESI(+)-MS) analysis. Identification of the phenolic compounds data was realized based on the UV spectra of each compound. Based on a calibration curve (R2 = 0.9985), the amounts of the phenolic compounds, expressed as mg cathechin equivalents (CE)/L, were calculated. The total phenolic content of the beer and vinegar samples determined using Folin–Ciocalteu reagent were of 428.9±1.58 and 661.5±7.69 mg GAE L-1, respectively, which contributed to the high antioxidant activity in the vinegar sample of 82.18 %. Statistically significant differences were observed after acetic fermentation between each parameter (p < 0.05). Brown beer vinegar represents a rich source of polyphenols and phenolic derivatives, compared to beer. By its increased phenolic content and antioxidant activity, brown beer vinegar could be considered another source of valuable compounds to beer, which could also be of interest in special diets.

This work examines the release rates in different solvents (polar and non-polar) of seabuckthorn oil encapsulated in different natural biopolymers (alginate, k-carrageenan and chitosan). The sea buckthorn oil was encapsulated using the ionotropically crosslinked gelation technique, and spherical orange beads with diameters ranging from 2 to 3 cm were obtained. The free and encapsulated seabuckthorn oil beads were characterized by Fourier transformed infrared (FTIR) spectroscopy. Determination of release rates of seabuckthorn oil (in hexane and methanol) was monitored by UV-Vis spectroscopy. Our experimental data indicated that release rates are determined by the diffusivity in the biopolymer matrices, and the solvent type, which influences the swelling of the beads. [ABSTRACT FROM AUTHOR]

Presently, in Romania, the cultivated area with plants for biofuel production represents 1,6% of the arable surface of the country, about 150 000 ha (in 2008). With an adequate promotion of the production technologies and usage of biofliel, at farm level, Romania could cover up to 8 % of the European need. Although there is an arable potential, and also there are the crops suitable for it (rape, soybean, sunflower, corn) Romania produces much less under the energetic potential it has. Regarding the future of biofuel there are investments in the domain, in the phase of project. [ABSTRACT FROM AUTHOR]

Vegetables comprise a significant portion of our daily diet with their high content in nutrients including fiber, vitamins, minerals, as well as phenolic compounds. Vegetable consumption has been shown to be positively associated with the prevention of several degenerative diseases thanks to their bioactive compounds. Accordingly, five selected vegetables, namely, red chicory, red onion, eggplant, purple sweet potato, and black carrot were thoroughly assessed for their phenolic content in this study. For this purpose, the total phenolic and flavonoid content of these five vegetables and their antioxidant activities that are based on three common methods ABTS radical cation decolorization assay (ABTS), Cupric Ion Reducing Antioxidant Capacity (CUPRAC), and DPPH scavenging activity assay were determined. Additionally, HPLC-PDA/Electrospray ionization coupled with mass spectrometry (HPLC-PDA/-ESI+-MS)-based identification and quantification of the members belonging to polyphenols present in each vegetable were determined. Statistical correlations between antioxidant activities and the specific type of phenolic compounds, such as anthocyanins, flavonoids, anthocyanins, and phenolic acids were further elucidated. Phenolic acids (chlorogenic and syringic acids) were found to be the most abundant compounds that are present in all samples. Among the anthocyanins, cyaniding derivatives were present in all vegetables. In terms of their antioxidant activities, the analyzed vegetables were ranked as red chicory > purple sweet potato > black carrot > eggplant > red onion, in descending order. Superior antioxidant activities exhibited by red chicory and purple sweet potato were attributed to the high content of phenolic compounds, especially flavonols (quercetin-3,4-O-diglucoside) in red chicory and anthocyanins (peonidin-3-caffeoyl p-hydroxybenzoylsophoroside-5-glucoside) in purple sweet potato.

Pesticide residues and microbial load on the surface of fresh fruits and vegetables becomes a major concern due to the safety and quality of these products for consumer.In order to minimize these risk factors (pesticide residues and microbial load), were achieved labels for fruits and vegetables that are consumed with shell which disintegrates under the influence of water jet and thus reduce the amount of these contaminants. Were elaborated labels based on polymer (chitosan) at a concentration of 2%, which incorporate bioactive compounds from green tea with potential decontaminant of the peel of this products. Green tea extract was obtained by infusing 1 g of dried green tea in 100 ml water at 80° C for 10 minutes. The extract was filtered and then mixed with 2 g chitosan acidified with 0.7% glacial acetic acid and dilute to the mark with distilled water. Were identified bioactive compounds from green tea, using UV-VIS and HPLC. Then were elaborated the labels. These tags were used on pepper, tomato, apple and nectarine. Were quantified the microbial load and the pesticide residues on their surface unwashed, washed only with water and were monitored the influence of labels on these factors. Identified pesticides were mefenoxan and thiamethoxam, which were quantified by HPLC. In what it concerns the influence, were founded the absence of germs at pepper and a significant decrease at the other. In terms of the potential of reducing pesticide, the experimental results have indicated that the label can prove its effectiveness.

Abstract Background The well–known prebiotics are carbohydrates but their effects may not always be beneficial, as they can also encourage the growth of non-probiotic bacteria such as Eubacterium biforme and Clostridium perfringens. Therefore, new alternatives such as non-carbohydrate sources to stimulate the growth of probiotics are needed. The aim of this work was to evaluate (I) the green tea polyphenols by HPLC-LC/MS and (II) the protective effect of green tea extract on viability and stability of B. infantis ATCC 15697 and B. breve ATCC 15700 microencapsulated in chitosan coated alginate microcapsules during exposure to simulated gastrointestinal conditions and refrigerated storage. Results The major compound identified by HPLC-LC/MS in green tea was epigallocatechin gallate followed by caffeine and epigallocatechin. The survival yield of probiotic bacteria in microcapsules with 10% GT during storage at 4°C, demonstrated significantly (P B.infantis and B. breve with 5% and 10% GT showed a significantly (P Conclusions The results of this study suggest that green tea coencapsulated with B. infantis or B. breve exert a protective effect of bacteria during exposure to gastrointestinal conditions and refrigerated storage. For a health perspective, the results confirm the growing interest probiotic bacteria and the perceived benefit of increasing their numbers in the gastrointestinal tract by microencapsulation.

Surface-enhanced Raman scattering (SERS) is emerging as a novel strategy for biofluid analysis. In this review, we delineate four experimental SERS protocols that are frequently used for the profiling of biofluids: 1) liquid SERS for the detection of purine metabolites; 2) iodide-modified liquid SERS for the detection of proteins; 3) dried SERS for the detection of both purine metabolites and proteins; 4) resonant Raman for the detection of carotenoids. To explain the selectivity of each experimental SERS protocol, we introduce a heuristic model for the chemisorption of analytes mediated by adsorbed ions (adions) onto the SERS substrate. Next, we show that the promising results of SERS liquid biopsy stem from the fact that the concentration levels of purine metabolites, proteins and carotenoids are informative of the cellular turnover rate, inflammation, and oxidative stress, respectively. These processes are perturbed in virtually every disease, from cancer to autoimmune maladies. Finally, we review recent SERS liquid biopsy studies and discuss future steps that are required for translating SERS in the clinical setting., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Inflammatory bowel diseases (IBDs) are conditions that still pose significant problems. A third of the patients are either misdiagnosed or a proper diagnosis of Crohn's disease (CD) or ulcerative colitis (UC) cannot be made. We need new biomarkers, so that we can offer patients the best treatment and keep the disease in an inactive state for as long as possible. Alterations in metabolic profiles have been incriminated in the pathophysiology of IBD. The aim of the present study was to identify molecules that could serve as biomarkers for a positive diagnosis of IBD as well as to discriminate UC from colonic CD. Twenty-two patients with active colonic IBD (UC = 17, CD = 5) and 24 age- and gender-matched healthy controls were enrolled. Plasma lipid and metabolic profiles were quantified using ultra-high-performance liquid chromatography combined with mass spectrometry. Univariate and multivariate statistical tests were employed. Six lipid species and 7 metabolites were significantly altered in IBD patients compared to healthy controls, with the majority belonging to glycerophospholipid, linoleic acid, and sphingolipid metabolisms. Five lipid species and only 1 metabolite were significantly increased in UC compared to CD. This preliminary study suggests that lipid and metabolic profiling of serum can become diagnostic tools for IBD. In addition, they can be used to differentiate between CD and UC.

The aim of this study was to evaluate the effect of the carotenoidic saponified extract of Physalis alkekengi sepals (PA) towards the lipoxygenase (LOX) oxidation of linoleic acid. Lipoxygenase activity in the presence of carotenoids, standard and from extract, was followed by its kinetic behaviour determining the changes in absorption at 234 nm. The standard carotenoids used were β-carotene (β-car), lutein (Lut), and zeaxanthin (Zea). The calculated enzymatic specific activity (ESA) after 600 s of reaction proves that PA carotenoidic extract has inhibitory effect on LOX oxidation of linoleic acid. A longer polyenic chain of carotenoid structure gives a higher ESA during the first reaction seconds. This situation is not available after 600 s of reaction and may be due to a destruction of this structure by cooxidation of carotenoids, besides the classical LOX reaction. The PA carotenoidic extract inhibiting the LOX-1 reaction can be considered a source of lipoxygenase inhibitors.

In an attempt to determine the antioxidant/prooxidant, antibacterial/probacterial action of flavan-3-ols and procyanidins from grape seeds, pure catechin (CS), and an aqueous grape seed extract (PE), were applied in the absence and presence of pure lipoxygenase (LS) or in extract (LE) to leucocyte culture, Escherichia coli B 41 and Brevibacterium linens, and observed whether there was any effect on lipid peroxidation, cytotoxicity, or growth rate. Short time periods of coincubation of cells with the polyphenols, followed by the exposure to LS and LE, revealed a high level of lipid peroxidation and a prooxidative effect. Longer coincubation and addition of LS and LE resulted in the reversal of the prooxidant action either to antioxidant activity for CS + LS and PE + LS or to the control level for CS + LE and PE + LE. Lipid peroxidation was significantly reduced when cells were exposed to polyphenols over a longer period. Longer exposure of E. coli to CS or PE followed by addition of LS for 3 h resulted in bactericidal activity. Significant stimulatory effect on microbial growth was observed for PE + LS and PE + LE treatments in B. linens, illustrating the potential probacterial activity in B. linens cultures. Lipoxygenase-polyphenols complex formation was found to be responsible for the observed effects.

The present study evaluates the antioxidant activity of two Aronia melanocarpa cultivars-Viking and Aron-and of Aronia prunifolia hybrid in relationship with their phytochemical composition regarding the contents of total phenolics, flavonoids, procyanidins, and monomeric anthocyanins. The antioxidant capacity of the mentioned extracts of chokeberries was evaluated through five complementary assays: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), H(2)O(2) scavenging potential, oxygen radical absorbance capacity, ferric reducing antioxidant power, and cupric ion reducing antioxidant capacity. A. prunifolia hybrid was found to have the highest antioxidant activity and to be the richest in polyphenols, procyanidins, and anthocyanins compared with the A. melanocarpa cultivars. A good correlation was observed between antioxidant activity and total procyanidin and anthocyanin content. Cyanidin glycosides inhibited HeLa human cervical tumor cell proliferation and increased generation of reactive oxygen species after 48 h of treatment, suggesting that they could be responsible for the antiproliferative activity. These results may be significant for industry concerning food quality and disease prevention.