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Best-performing Bacillus strains for microbiologically induced CaCO3 precipitation: Screening of relative influence of operational and environmental factors
No full textThe microbiologically induced calcite precipitation (MICP) can be an emerging approach that could tap onto soil bacterial diversity and use as a bioremediation technique. Based on the concept that bacteria with biomineralization capacity could be effective CaCO3 inductance agents, this study aimed to evaluate the simultaneous influence of 11 operational and environmental factors on the MICP process, for the first time. Therefore, Bacillus muralis, B. lentus, B. simplex, B. firmus, and B. licheniformis, isolated from alkaline soils, were used in the selection of the best performing bacterium compared with a well-known MICP bioagent Sporosarcina pasteurii DSM 33. Plackett-Burman's experimental design was labouring to screen all independent variables for their significances on five outputs (pH value, number of viable cells and spores, amount of urea and CaCO3 precipitate). According to experimentally obtained data, an artificial neural network model based on the Broyden-Fletcher-GoldfarbShanno algorithm showed good prediction capabilities, while differences in the relative influences were observed at the bacterial strain level. B. licheniformis turn out to be the most potent bioagent, with a maximum amount of CaCO3 precipitate of 3.14 g/100 mL in the optimal conditions
The effect of process parameters and catalyst support preparation methods on the catalytic efficiency in transesterification of sunflower oil over heterogeneous KI/Al2O3-based catalysts for biodiesel production (vol 315, 123246, 2022)
No full textOutput prediction model for twelve primal and commercial cuts from pork carcasses
No full textDeveloped empirical models for the assessment of total lean meat percentage and weight of pork carcass halves, according to data of the total lean meat percentage, total lean meat content and total cold carcass weight were a reasonable fit to the experimental data and successfully predicted the percentages of pork primals (ham, loin, neck, head and cheek - HAC, front shank and front foot - FSFF, hind shank and hind foot - HSHF, tenderloin - TEN, shoulder, jowl, belly, ventral part of the belly 1 - VPB1 and ventral part of the belly 2 - VPB2). A total of 455 experimentally obtained data points were used to build a prediction model. The ANN model, based on the Broyden-Fletcher-Goldfarb-Shanno iterative algorithm, showed good prediction capabilities. The overall R-squared values during training, testing, and validation cycles for the before-mentioned output variables were as follows: 0.823, 0.749, 0.789, 0.836, 0.551, 0.868, 0.808, 0.857, 0.829, 0.483, 0.756 and 0.574, respectively
Polyphenolic and Chemical Profiles of Honey From the Tara Mountain in Serbia
No full textThis study presents a detailed characterization of 27 honey samples from the Tara Mountain region in Serbia using different comprehensive techniques and methods. The types of the honey samples were defined as monofloral (4 samples), honeydew (5 samples) and polyfloral (18 samples) honey based on determined polyphenol content, antioxidant activity, electrical conductivity and melissopalynological analyses. Physicochemical parameters such as pH (4.13-4.94), diastase activity (24.20-41.70 DN), acidity (14.60-29.70 meq/kg), content of 5-(hydroxymethyl)furfural (in range below 5, up to 16.90 mg/kg), sucrose (0.20-3.90 g/100 g), and moisture content (15.01-19.23%) confirmed the required quality of the honey samples. Sensory analysis revealed honey characteristics favorable to consumers. Analyses of 19 phenolic compounds using ultra-high-performance liquid chromatography with a diode-array detection and triple quadrupole mass spectrometry (UHPLC-DAD-MS/MS) revealed six phenolic acids and 13 other compounds from the group of flavonoids and their glycosides. In all the samples the highest content was determined for p-coumaric acid, followed by caffeic acid and pinocembrin. Besides total phenolic content and radical scavenging activity, antimicrobial activity was also examined. Most honey samples showed bactericidal activity against Staphylococcus aureus and bacteriostatic activity against Escherichia coli, while none of the honey samples inhibited the growth of Candida albicans. Chemometric analyses were applied for an in-depth study of the results to further evaluate the characteristics of the honey samples studied. Principal component analysis (PCA) was used for assessing the differences in physicochemical parameters, polyphenols content and antioxidant capacity between honey samples. The unrooted cluster tree was used to group the samples based on the melissopalynological analyses
Insights into sensory and hedonic perception of wholegrain buckwheat enriched pasta
No full textThis study investigated different wholegrain wheat/wholegrain buckwheat blends to develop functional pasta with unique sensory properties. The impact of the buckwheat flour type (native or hydrothermally treated) and ratio between wholegrain wheat and buckwheat flour in pasta formulation on the sensory profiles and hedonic perception of pasta was studied. A range of techniques (principal component analysis, preference mapping, cluster analysis, penalty analysis) have evolved to combine data from sensory panel, data collected from consumers and data related to the product to provide valuable insights into the way in which sensory properties drive consumer preferences and how pasta can be design to give the sensory properties desired by the consumer. Generally, even though buckwheat flour incorporation decreased consumer acceptability, the results indicated that hydrothermal pre-treatment of buckwheat flour has promising potential to be implemented in the production process of buckwheat containing pasta, since this treatment was efficient in reducing pasta bitterness and grittiness which were negatively evaluated and strongly penalized by consumers
Recovery of biologically active compounds from stinging nettle leaves part I: Supercritical carbon dioxide extraction
No full textStinging nettle is annual plant from Urticaceae family used as food and medicine. Due to the nonsufficient data, this work aimed to isolate the bioactive compounds from the stinging nettle leaves by supercritical carbon dioxide. Extracts were analyzed and assessed for antioxidant and cytotoxic activities. Main fatty acids were alpha-linolenic (31.06-58.42 mg/g E), palmitic (9.17-13.12 mg/g E), and linoleic (10.93-16.51 mg/g E) acids. Chlorophylls (33.00-7365.11 mg/100 g E) and carotenoids (166.88-722.62 mg/100 g E) were also found in all samples. Four empirical kinetic equations were effectively utilized for kinetic modeling of supercritical fluid extraction. As per proper statistical features, empirical models show good concurrence with experimental data. The numerical modeling of a process is gainful to foresee the process conduct and furthermore extend the methodology from laboratory to industrial scales. The principal component analysis was used to visualize the fatty acids profile, antioxidant capacity, and cytotoxic activity of extract
Obtaining DHA-EPA Oil Concentrates from the Biomass of Microalga Chlorella sorokiniana
No full textMicroalgae have attracted growing interest all around the world due to their potential applications in multiple sectors of industry, such as energetics, nutraceuticals, pharmaceuticals, agriculture, and ecology. Concepts of biorefinery of microalgae lipids for biodiesel production coupled with other applications have been suggested in several studies. However, very few studies focus on overcoming the degree of unsaturation of microalgae lipids using methods of fractionation. This study presents a method for obtaining two oil fractions from microalgae Chlorella sorokiniana suitable for food and biofuels via urea complex formation with further production of a long-chain PUFA concentrated oil suitable for the nutraceutical industry. A DHA-EPA-rich fraction was obtained from the dry microalga biomass using a succession of extraction, urea-complexation, fractionation, and esterification with glycerol. Analytical and organoleptic methods were used to assess the quality of the final product. Results show that the urea-complexation method allowed the obtaining of two lipid fractions with different fatty acid profiles. The urea complexed fraction (UCF) contained a majority of saturated fatty acids (54.46%); thus, it could find applications in the biofuels or food industry. The non-urea complexed fraction (NUCF) was rich in polyunsaturated fatty acids (PUFA) (81.00%), especially long-chain PUFA with 16.52% EPA and 35.08% DHA. The recovery rates of EPA and DHA in the NUCF reached 59% and 87.14%, respectively. Finally, the physicochemical and organoleptic characteristics of the DHA-EPA oil concentrate were determined and found conform to the norms recommended by the WHO/FAO standards for edible oils and the Russian State Standard GOST 1129-2013
Variation of Salvia officinalis L. Essential Oil and Hydrolate Composition and Their Antimicrobial Activity
No full textThis study aimed to investigate the chemical composition of steam distillate essential oil and corresponding hydrolate obtained from S. officinalis grown in Serbia, as well as the influence of weather conditions (temperature and precipitations) on their chemical profiles. Furthermore, their antimicrobial activity was investigated in vitro. The main compounds in essential oil were cis-thujone, followed by camphor, trans-thujone, and 1,8-cineole, while hydrolate was slightly different from the essential oil, with camphor, cis-thujone, and 1,8-cineole as the main compounds. Among the eight respiratory-associated microorganisms, Klebsiella oxytoca was the most sensitive to the tested EOs (minimum inhibitory concentration (MIC)/minimal bactericidal/fungicidal concentration (MBC/MFC) were 14.20 and 28.4 mu L mL(-1), respectively). MIC and MBC values of other tested bacteria ranged between 28.40 and 227.25 mu L mL(-1) while for Candida albicans MIC/MFC ranged from 28.40/56.81 to 56.81-113.63 mu L mL(-1). Antibiotic susceptibility patterns for the analyzed eight respiratory-associated microorganisms showed an intermediate level of resistance to commonly used antibiotics such as ampicillin, levofloxacin, and ciprofloxacin. As a preliminary approach to the antimicrobial profiling of the tested EO, the obtained results revealed that the tested samples possess remarkable antibacterial activities and could be used to develop pharmaceutical formulations as an alternative to conventional antibiotic therapy
Elderberry (Sambucus nigra L.) wine as a novel potential functional food product
No full textThroughout human civilization, elderberry (Sambucus nigra L.) has been used as a traditional drug and addition to various dishes. Although it is a widespread plant species, it is still being researched and rarely used to obtain new products. In this study, we focused on the chemical and phytochemical composition and biological and pharmacological effects of elderberry wine, obtained by applying different temperature treatments (without temperature treatment - W1; 60 degrees C, 5 min - W2; 60 degrees C, 10 min - W3; and 70 degrees C, 5 min - W4). HPLC-MS/MS and spectrophotometric techniques determined the chemical and phytochemical profiles of obtained wines. The main compounds in analyzed wines were p-Hydroxybenzoic, protocatechuic and chlorogenic acids, quercetin, quercetin-3-O-hexoside, and rutin. To assess the biological potential, antioxidant, neuroprotective (acetyl-and butyr-ylcholinesterase inhibition), antityrosinase, and antidiabetic (amylase inhibition and glucosidase inhibition) abilities were examined. Wine W4 showed the strongest antioxidant activity, which correlated well with the high phenol content. The best inhibitory effect of beta-glucosidase was observed in wine W3. However, the most potent tyrosinase inhibitor was wine W4. The presented results prove elderberry wine's high biological and industrial potential and open new avenues for formulating new products that could be brought to market
Yogurt fortified with GABA-producing strain and Ganoderma lucidum industrial waste
No full textThis study aimed to produce yogurt with Ganoderma lucidum residues and selected probiotic bacteria. To select the most potent GABA-producing strain (GABA - gamma-aminobutyric acid), nine probiotic bacteria were subjected to the glutamate decarboxylase (GAD) activity assay. Limosilactobacillus reuteri DSM 17938 was selected and used in preparing fresh yogurts, with and without supplementation of Ganoderma residues obtained after water extraction [GW (Ganoderma waste) 2% (w/v)]. A decrease in pH during fermentation and the occurrence of syneresis were investigated. Lactic acid bacteria (LAB) viability and anti-Escherichia activity were estimated. Further, the cytotoxic effect of yogurt extracts on the human colon cancer cell line (HCT116) was surveyed. Besides functionality, the sensory attributes were evaluated. The pH values did not significantly change with the GW addition while increasing the LAB counts [up to 9.76 +/- 0.11 log colony-forming units (CFU) mL(-1)] and the cytotoxic effect on HCT116 cells. Yogurt produced with selected bacteria and GW had the most valuable anti-coli effect against E. coli 0157: H7 and E. coli ATCC 35218 (American Type Culture Collection, Rockville, Maryland) (4.81 +/- 0.62 and 5.64 +/- 0.29 CFU mL(-1), respectively). Although the added GW increased the yogurt functionality, it had a slightly negative effect on the taste and texture of the partially modified recipe. Yogurts fortified with GABA-producing strain and GW could potentially reduce relapse rates of depressive disorders