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What could be the reason for different behavior of phosphate tungsten and phosphate molybdenium bronzes in Briggs-Rauscher reaction: new insight
No full textRecently, two different effects of phosphate tungsten (PWB) and phosphatemolybdenum (PMoB) bronzes (obtained by thermal treatment), on oscillatoryBriggs-Rauscher (BR) dynamic have been found [1]. Although both are insoluble inBR solution [2], the addition of different masses of PWB linearly decreases the BRoscillation time, while the addition of different masses of PMoB had no effects onthe BR reaction. Furthermore, PWB has an identical role as metal catalyst Mn2+ inBR reaction and for obtained behavior is probably responsible the differentmechanisms of heterogeneous catalysis of these bronzes in oscillatory reaction.Therefore, a deeper investigation was done in order to find the major structuralcharacteristic of these two bronzes by using the XRPD method.What is so different for these two bronzes, causing dissimilar effects in BRreaction, is it “just” catalytic activity of central cation or there is something more?The XRPD method confirmed very different structures of PWB and PMoB asmonoclinic and orthorhombic, respectively [3,4]. This work tries to connect thestructural properties of PWB and PMoB with BR oscillatory reaction responses,expanding the usage of oscillatory reaction in material science and catalysis, ingeneral
APPLE POMACE AS CARRIER FOR STARTER CULTURE USED IN PRODUCTION OF YOGURT INTENDED FOR DEPRESSION TREATMENT: NEW APPROACH
No full textAntioksidativni, citotoksični i neurobiotski potencijal suplementacije sremskog sira prahom jestivih pečuraka
No full textMedicinal mushroom nutraceutical commercialization: Two sides of a coin
No full textHigher fungi (Basidiomycetes) have been heavily researched in the last two decades, which makes the beginning of the 21st century known as the age of fungiceuticals. The wide pool of in vitro and in vivo data, as well as clinical studies, promise us miraculous natural agents. However, the industry has its own stance in the case of mushroom nutraceuticals. This chapter provides the overview of different aspects of medicinal mushroom commercialization: from the explanation of this new segment of products, over proper fungal material identification, choosing the raw material, dosing, bioavailability and drug delivery systems, safety and quality, organic certification, strategies in formulating them, to emerging fields of potential use, including antiviral products. Each of these aspects is discussed from both the positive and negative side present in today's industry and market
Green Techniques for Preparation of Red Beetroot Extracts with Enhanced Biological Potential
No full textRed beetroot is well known for its high proportion of betalains, with great potential as functional food ingredients due to their health-promoting properties. The objective of this study was to investigate the influence of processing techniques such as Soxhlet, cold, ultrasound and supercritical fluid extraction on the betalains content and its antioxidant, anti-inflammatory and antihyperglycemic activities. Whilst Soxhlet extraction with water has provided the highest yield, the highest content of total phenolics was found in an extract prepared using Soxhlet extraction with 50% ethanol. Amongst eight phenolic compounds detected in the extracts, protocatechuic acid was the most abundant. The concentrations of total phenolics ranged from 12.09 mg/g (ultrasound extraction with 30% methanol) to 18.60 mg/g (Soxhlet extraction with 50% ethanol). The highest anti-inflammatory activity was observed for cold extraction with 50% methanol extract. The high radical scavenging activity of supercritical fluid extracts could be a consequence of nonphenolic compounds. The chemometrics approach was further used to analyse the results to find the "greenest" method for further possible application in the processing of beetroot in the food and/or pharmaceutical industry. According to the standard score, the best extraction method was determined to be Soxhlet extraction with 50% ethanol
Influence of the mowing and drying on the quality of the peppermint (Mentha x piperita L.) essential oil: Chemical profile, thermal properties, and biological activity
No full textIn this study, the influence of the mowing and drying on the chemical profile, thermal behavior, antioxidant activity (DPPH, CUPRAC, FRAP, ABTS, HRSA, and TBARS), microbiological data (Candida albicans (ATCC 10231), Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 25922), Candida albicans (ATCC 10231), Bacillus subtilis (ATCC 6633), Proteus vulgaris (ATCC 13315), Proteus mirabilis (ATCC 14153) and Aspergillus niger (ATCC 16404) and cytotoxic activity of peppermint samples (HeLa, LS-174, A549, and MRC-5) was investigated. Chemical profiles showed that mowing did not have a significant impact on essential oil composition compared to drying. Menthone was the principal compound in essential oil from the fresh material, while menthol was the main compound in the samples from the dried ones. These differences influenced the biological activity of the samples, where fresh had better antioxidants, while dried had better antimicrobial activity. Thermal analysis showed that samples completely evaporated to about 120-123 degrees C in non-isothermal conditions, while in isothermal conditions the time required for complete evaporation was 20-30 min, depending on the sample. An artificial neural network model was developed, for the anticipation of antioxidant activity. These models showed good prediction properties (the r2 value during the training cycle for output variables was 1.000)
Inulin Determination by an Improved HPLC-ELSD Method
No full textSince inulin utilization as a sugar or fat replacer, texture modifier, and emulsifier is increasing in the food industry, there is a need for its determination for food control and labeling. This study reports the development and validation of an advanced high-performance liquid chromatographic method with evaporative light-scattering detection (HPLC-ELSD) method for inulin quantification, with optimized extraction conditions (1:10 w/v solid-to-solvent ratio, 1 h/80 degrees C in a water bath continued with 30 min ultrasonication for the extraction step, and precipitation during the night with four volumes of acetone). The rapid HPLC-ELSD analysis (16 min) has been performed by isocratic elution with water as a mobile phase and optimized detector parameters (temperature of evaporator 80 degrees C, temperature of nebuliser 80 degrees C, gas flow rate 1.3 standard liters per minute, detector gain 1). The method was validated in terms of limits of detection and quantification, intra- and inter-day precision and accuracy, and recovery. The proposed method was carried out using a cation exchange (Ag +) column for the first time for the inulin determination, avoiding the hydrolysis step in order to simplify and accelerate the quantification
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
No full textThe essence of this study is synthesis of a newly developed and efficient heterogeneous catalyst based on aluminum oxide support promoted with potassium iodide (KI) as active dopant responsible for pronounced catalyst activity. Modified sol-gel, reflux and hydrothermal method were used for synthesis of aluminum-oxide support using aluminum isopropoxide as a precursor. The gamma-Al2O3 support and KI/gamma-Al2O3 catalyst samples were examined by various experimental techniques. Effects of several operational parameters were considered and those are: methanol to sunflower oil molar ratio, catalyst loadings, reaction time and reaction stirring rate. The obtained results indicated that modified sol-gel method for synthesis of gamma-Al2O3 catalyst support is the most favorable for obtaining the catalyst with superior catalytic performances in transesterification of sunflower oil. A maximum conversion (triglycerides to methyl esters) of 99.99% was achieved using the SG-KI/gamma-Al2O3-770 catalyst under following optimal process parameters: 15:1 methanol to sunflower oil molar ratio, 2.5 wt% catalysts loading, 600 rpm stirring rate and 4 h of the reaction run
Storage time effect on inoculated, osmodehydrated chicken meat-microbiological and chemical characteristics
No full textIn this research, chicken meat was inoculated with selected microorganisms and subjected to the osmotic dehydration process in two osmotic solutions, in an effort to investigate the effect of storage time duration on its microbiological and chemical characteristics. Total viable counts, numbers of Enterobacteriaceae, Salmonella spp., Listeria monocytogenes, Escherichia coli, proteolytic bacteria, psychotropic bacteria, of microbiological, and biogenic amine content, TBARS and DPPH, and chemical analyses were conducted on meat samples stored at 22 degrees C, during 14 days. During storage, the number of all tested microorganisms on meat samples decreased. The highest reduction occurred in the first 4 days. The meat dehydrated in molasses achieved better results of microbiological profile during storage. Results of TBARS and DPPH analyses indicated lipid oxidation after 14 days of storage, while the results after 10 days were satisfactory. Developed mathematical models allows good prediction of microbiological and chemical responses of dehydrated chicken meat during the investigated storage duration
Indigo Carmine in a Food Dye: Spectroscopic Characterization and Determining Its Micro-Concentration through the Clock Reaction
No full textIndigo carmine is a commonly used industrial blue dye. To determine its concentration in a commercially available food dye composed of a mixture of indigo carmine and D-glucose, this paper characterizes it through (ATR, KBr) FTIR micro-Raman as well as UV/Vis and clock: Briggs-Rauscher (BR) oscillatory reaction methods. The indigo carmine was detected in the bulk food dye only by applying micro-Raman spectroscopy, indicating a low percentage of the indigo carmine present. This research provides an improvement in the deviations from the experimental Raman spectrum as calculated by the B97D/cc-pVTZ level of theory one, resulting in a better geometrical optimization of the indigo carmine molecule compared to data within the literature. The analytical curves used to determine indigo carmine concentrations (and quantities) in an aqueous solution of food dye were applied by means of UV/Vis and BR methods. BR yielded significantly better analytical parameters: 100 times lower LOD and LOQ compared to commonly used UV/Vis. The remarkable sensitivity of the BR reaction towards indigo carmine suggests that not only does indigo carmine react in an oscillatory reaction but also its decomposition products, meaning that the multiple oxidation reactions have an important role in the BR's indigo carmine mechanism. The novelty of this research is the investigation of indigo carmine using a clock BR reaction, opening new possibilities to determine indigo carmine in other complex samples (pharmaceutical, food, etc.)