Thermal Stability Study of the Grape Seeds Extracts in the Aqueous Solutions

This study was carried out to evaluate the effect of parameters the extraction process of grape seeds extracts on the bioactive compounds. The aqueous extracts were screened for total polyphenol content and total flavonoid content wich were determined spectrophotometrically using a modified Folin-Ciocalteu method, respectively a chromogenic system of NaNO2-Al (NO3)3-NaOH based method. The antioxidant activity was determined using DPPH method while  their polyphenolic composition by means of HPLC-DAD- MS/ ESI(+) analysis. Total phenols content and flavonoid content varied between 37.835 and 31.830 mg GAE/g, 23.420 and 17.645 mg QE/g respectively in Fetească Neagră seeds; between 24.265 and 27.065 mg GAE/g, 17.970 and 15.205 mg QE/g respectively in Fetească Regală seeds. All extracts showed remarkable DPPH radical-scavenging activity ranging from 94.110 to 95.515%. The study revealed 14 phenolic compounds belonging to the following groups: flavan-3-ol monomers, proanthocyanidins, hydroxycinnamic acid and hydroxybenzoic acid derivatives. Quantitative differences among the varieties and the level of temperature applied of  the extraction process were observed. The results suggested that the heat treatment of grape seeds liberated phenolic compounds having a significant effect in increasing the amounts of active when a 90°C extraction temperature was used

Preparation and Comparative Characterization of Alginate-Made Microcapsules and Microspheres Containing Tomato, Seabuckthorn Juices and Pumpkin Oil

Recent studies have shown the benefits of tomatoes, seabuckthorn juices and pumpkin oil, rich in bioactives with antioxidant capacity, in the prevention of prostate diseases. To stabilize their antioxidant activity, microencapsulation represent a good technological alternative, improving the stability and bioavailability of bioactive molecules ( phenolic derivatives, carotenoids, phytosterols, vitamins).   The aim of the study was to prepare and characterize microspheres and microcapsules based on emulsions made of natural polymers like Natrium alginate mixed with tomato and/or seabuckthorn juices, with or without pumpkin oil.  The viscosity of emulsions, the morphology of microcapsules and microspheres were characterized comparatively and the bioactives were monitored by UV-Vis spectrometry.  In the lipophilic extract there were identified, before and after encapsulation, different classes of compounds, from lipids, to phenolic acid derivatives, flavonoids and carotenoids. Carotenoids were the major components having concentrations from 9.16 up to 19.71 mg/100 g sample. The viscosity of  each emulsion including juices, oil and natrium alginate 2%, before encapsulation, showed differences, dependent on the oil addition and speed of homogenization. The macroscopic and microscopic structure of microspheres and microcapsules were comparatively evaluated. Both microspheres and microcapsules had external diameters  ranging from 750 to 900 μm and the microcapsules’ oily core of 150-180 μm. The results obtained from emulsion’s viscosity will be correlated with the rigidity and optimal release rate of bioactive molecules from microcapsules and microspheres.  Further studies are directed towards these aspects

Comparative Assessment of Phenolic Compounds from Authentic Wine Varieties from North-Western Romania from the 2021-2022 Harvest

Wine is one of the most consumed beverages in the world. Romania, as a country, has a history in vineyards and wine making. This present study analyzed the phenolic compounds of 5 varieties of wine from Romania (Fetească Regală Muscat Ottonel, Riesling Italian, Pinot Gris and Merlot). The results suggested that some of the wines present a wide category of phenolic compounds where others present low values and some of the compounds are absent as detected with a developed HPLC-DAD-ESI+ method. Phenolic compounds were identified after the retention time. Merlot wine presented, in most cases, the highest values for phenolic compounds, with a few exceptions. As a conclusion, romanian wines are rich in phenolic compounds that possess a series of beneficial properties

From grape to wine - Muscat Ottonel from Blaj-Târnave vineyard chemical and sensory analysis

Following the global trend of selling high-quality wines, those produced in Blaj vineyard must be superior due to a highly competitive market and consumer tastes and demands. Because the quality of wine is given by both sensory and chemical properties this work presents the phenolic fingerprint, the general chemical characteristics, and the sensory properties of the 2021 Blaj Muscat Ottonel wine as well as the phenolic composition of the grapes from which this wine was produced. Grape phenolics were represented by flavanols (73%), flavonols (14%), hydroxybenzoic acids (9.08 %) and hydroxycinnamic acids (4%), while wine phenolics by flavanols (42%), hydroxycinnamic acids (33%) and hydroxybenzoic acids (15%). Catechin and procyanidin dimer B1 were identified both in grapes and in wine. More than half of the grapes’ procyanidin dimer B1 (3.638 mg/g out of 6.379 mg/g) and more than one-tenth of grapes’ catechin (1.570 mg/g out of 9.298 mg/g) were found in wine. As the general and sensory qualities of the Blaj Muscat Ottonel wine were kept within the limits of a Protected Designation of Origin (PDO) demi-sweet wine, the presence of resveratrol glucoside, catechin, and procyanidin in its content supports the idea of classifying this wine as a potential nutraceutical ‘functional wine’

Comparative HPLC-DAD-ESI(+)MS Fingerprint and Quantification of Phenolic and Flavonoid Composition of Aqueous Leaf Extracts of <i>Cornus mas<i> and <i>Crataegus monogyna</i>, in Relation to Their Cardiotonic Potential

Our study aimed to compare the phenolic and flavonoid composition of two medicinal plants from the wild flora of Romania, traditionally known to be efficient in preventing cardiotoxicity: Cornus mas and&nbsp;Crataegus monogyna. As most previous studies have focused on fruits, our investigations aimed to fingerprint and quantify the two classes of compounds in&nbsp;aqueous leaf extracts, based on HPLC-DAD-ESI(+)MS analysis. The specific HPLC-DAD fingerprint was coupled with UV spectra at 280 and 340 nm to discriminate between three subclasses of compounds: two hydroxycinnamic acids and a flavonoid glycoside. While the C. monogyna extract contained more than 98% vitexin isomers (2'- and 4'-O-rhamnoside), the C. mas extract was very complex, containing a mixture of phenolic derivatives and flavonoid glycosides. The spectral patterns of C. mas, combined with the molecular mass and specific fragmentations allowed the identification of epi-catechin, coumaric and caffeic acids and quercetin derivatives. Based on LC-MS peak area and parallel calibrations with gallic acid and rutin, the mean concentration for flavonoids in C. mas was 13 mg/100 ml, while aprox. 65 mg/100 ml in C. monogyna extracts. Using the Folin method, the total phenol content was 105 mg/100 ml in C. mas and around three times less in the C. monogyna extract, while the antioxidant activity was increased only 1.5-1.7 times in C. mas extract compared to C. monogyna. These findings suggest a higher stability and potential of flavonoids to act as antioxidants in hydrophilic environment

Exploitation of Lactic Acid Bacteria and Baker’s Yeast as Single or Multiple Starter Cultures of Wheat Flour Dough Enriched with Soy Flour

Sourdough fermentation presents several advantageous effects in bread making, like improved nutritional quality and increased shelf life. Three types of experiments aimed to evaluate comparatively the efficiency of two Lactobacillus (Lb.) strains, Lb. plantarum ATCC 8014 and Lb. casei ATCC 393, to metabolize different white wheat flour and soybeans flour combinations to compare their efficiency, together with/without Saccharomyces cerevisiae on sourdough fermentation. For this purpose, the viability, pH, organic acids, and secondary metabolites production were investigated, together with the dynamic rheological properties of the sourdough. During sourdough fermentation, LAB presented higher growth, and the pH decreased significantly from above pH 6 at 0 h to values under 4 at 24 h for each experiment. Co-cultures of LAB and yeast produced a higher quantity of lactic acid than single cultures, especially in sourdough enriched with soy-flour. In general, sourdoughs displayed a stable, elastic-like behavior, and the incorporation of soy-flour conferred higher elasticity in comparison with sourdoughs without soy-flour. The higher elasticity of sourdoughs enriched with soy-flour can be attributed to the fact that through frozen storage, soy proteins have better water holding capacity. In conclusion, sourdough supplemented with 10% soy-flour had better rheological properties, increased lactic, acetic, and citric acid production

Micropropagation of <i>Vaccinium corymbosum</i> L.: An Alternative Procedure for the Production of Secondary Metabolites

In vitro culture has become a dependable approach for the mass production of plant material as the market for innovative plant-derived medicinal approaches has grown significantly. Furthermore, because it permits manipulation of biosynthetic routes to boost the production and accumulation of certain compounds, this technology has enormous potential for the manufacture of natural bioactive chemicals. As a result, the goal of this study was to develop an efficient micropropagation system for biomass production and to investigate the accumulation of bioactive compounds from Vaccinium corymbosum L., Duke and Hortblue Petite cultivars. Two in vitro plant tissue culture systems were used for shoots production: a solid medium (5 g/L Plant agar) and liquid medium (Plantform bioreactor). The culture medium used was Woddy Plant Medium (WPM) supplemented with two growth regulators: 0.5 mg/L and 1 mg/L zeatina (Z) and 5 mg/L N6-(2-Isopentenyl) adenine (2iP). The content of phenolic compounds, carotenoids, and chlorophylls of the in vitro shoot extracts were examined via the HPLC-DAD-MS/MS technique. The results showed that cv. Hortblue Petite produced a higher amount of biomass compared with cv. Duke, on all variants of culture media in both systems (solid and liquid), while the shoots extract of the Duke variety in the liquid culture system (under all concentrations of growth regulators) had the highest content of total phenolic compounds (16,665.61 ± 424.93 μg/g). In the case of the lipophilic compounds analysed (chlorophylls and carotenoids), the solid medium reported the highest values, whereas media supplemented with 0.5 mg/L Z was proved to have the richest total content for both cultivars

Biodiesel-Derived Glycerol Obtained from Renewable Biomass—A Suitable Substrate for the Growth of Candida zeylanoides Yeast Strain ATCC 20367

Used kitchen oil represents a feasible and renewable biomass to produce green biofuels such as biodiesel. Biodiesel production generates large amounts of by-products such as the crude glycerol fraction, which can be further used biotechnologically as a valuable nutrient for many microorganisms. In this study, we transesterified used kitchen oil with methanol and sodium hydroxide in order to obtain biodiesel and crude glycerol fractions. The crude glycerol fraction consisting of 30% glycerol was integrated into a bioreactor cultivation process as a nutrient source for the growth of Candida zeylanoides ATCC 20367. Cell viability and biomass production were similar to those obtained with batch cultivations on pure glycerol or glucose as the main nutrient substrates. However, the biosynthesis of organic acids (e.g., citric and succinic) was significantly different compared to pure glycerol and glucose used as main carbon sources