Pressurized-Liquid Extraction as an Efficient Method for Valorization of Thymus serpyllum Herbal Dust towards Sustainable Production of Antioxidants.

The aim of this study was to valorize Thymus serpyllum herbal dust, a particular fraction distinguished as an industrial waste from filter-tea production. Pressurized liquid extraction (PLE) was used with the aim of overcoming certain obstacles of conventional extraction techniques in terms of shortening extraction time, reducing solvent consumption and energy costs, using "green" solvents and obtaining high yield and quality products. In order to optimize PLE of T. serpyllum herbal dust, the preliminary screening of the independent variables in order to define the most influential parameters and their domain was done first. After the screening, the optimization study using the face-centered central composite experimental design (CCD) with response surface methodology (RSM) was implemented. Additionally, taking into account the high awareness of the positive influence of antioxidants on the human health and associating it with high content of polyphenolic compounds in various members of Lamiaceae family, PLE has proven to be a great approach for antioxidants recovery from T. serpyllum herbal dust.

Study on the effects of smooth roll grinding conditions on reduction of wheat middlings using response surface methodology.

Influence of the milling parameters on the reduction process of the wheat middlings by the smooth rolls was investigated. Three level and four variables Box-Behnken experimental design with response surface methodology was applied in order to evaluate effects of milling parameters and to optimize grinding conditions for various responses. As independent variables roll gap (0.04-0.1 mm), differential (1.1.-1.9), roll speed (300-500 rpm) and feed rate (0.2-0.4 kg/cm min) were employed. Responsive variables were flour yield, ash content and energy consumption. In order to optimize milling process adequate models were obtained by regression analysis. Possibilities of the optimization of the milling parameters in order to obtain different combination of the desired outputs are illustrated by four examples.

Using the breakage matrix approach for monitoring the break release in the wheat flour milling process.

BACKGROUND: The breakage matrix approach is a mathematical tool to relate input and output particle size distribution from a milling operation. Adjustment of the break release in the flour milling process is extremely important because it affects granulation and quality characteristics of the stock and hence the total results and balance of the mill. In this study the breakage matrix approach has been used for the purpose of controlling the release on the front passages of the break system in the flour milling process. RESULTS: It has been established that, for any particle size distribution of wheat, it is possible to predict break releases together with the distribution of the release size fractions by using the breakage matrices. Also, the reversibility of this approach is examined, that is the possibility to identify the wheat particle size distribution that would result in desired break releases and/or the desired yields of different sized intermediate stocks under the given set of milling conditions. CONCLUSION: It is confirmed that the breakage matrix approach can be successfully used to predict the break releases. The reverse breakage matrix concept allows the determination of the wheat particle size distribution which would result in a targeted break release. © 2016 Society of Chemical Industry.

Using the eight-roller mill in the purifier-less mill flow.

Double grinding of mill streams without intermediate sieving, i.e. the eight-roller milling system provides opportunities for significant reduction of capital cost compared to conventional wheat flour milling system. In this study the effects of using the eight-roller mill in the purifier-less mill flow were investigated. Middlings from the break system of commercial flour mill, which would be sent to the purification system, were intercepted and employed in the experiments. Milling results obtained with double grinding of middlings were compared with the results obtained by conventional system with intermediate sifting before regrinding of stock. At the same roll gap setting and under the same sieving conditions, the eight-roller system produced less flour compared to the conventional system. Results showed that the most efficient way to increase flour yield in the eight-roller milling system is to increase the upper size limit of flour by increasing the sieve aperture. This is not followed by the deterioration of flour quality as determined by ash content. Increase of the upper size limit of flour particles is followed by the decrease of the flour ash content suggesting that it is possible to implement the eight-roller mills in the purifier-less mill flow.

Occurrence of contaminants of emerging concern in different water samples from the lower part of the Danube River Middle Basin - A review.

This study intends to assess the extent of the occurrence of CECs in different water types based on the literature data reported for the countries from a lower part of the Middle Danube Basin, including those belonging to the Western Balkan (WB) region and two upstream neighboring EU Member States, Croatia and Slovenia. These countries share main freshwater courses important for drinking water supply, agriculture, industry, navigation, tourism, etc, but in some of them there are low rate of wastewater treatment, impacting the chemical status of water resources in the region and probably beyond, if downstream countries are considered. The literature survey revealed 38 investigative studies reporting data on CECs in water matrices sampled in the region in the period 2008-2022. Surface water was the most frequently studied water type in WB countries, while wastewater was the dominant water type studied in Slovenia and Croatia. The most often analyzed compounds in the studies dealing with surface water and wastewater were the anti-epileptic drug carbamazepine, some non-steroidal anti-inflammatory drugs, and antibiotics; pharmaceutically active compounds were also the most analyzed CECs in groundwater and drinking water. Additionally, similarities/dissimilarities among the experimental approaches in these studies were discussed in relation to the state-of-the-art research directions for the CECs surveillance in the European Union, resulting in summarized strengths and gaps in capacities for the wide-range surveillance of CECs in the lower part of the Middle Danube Basin. This is the first integral overview of the studies on CECs in waters from the countries belonging to this part of the Danube Basin, representing a valuable baseline for further enhancement of the relevant monitoring efforts and chemical status of the regional water resources, especially in countries with poor wastewater management.

Green Extraction Approach for Isolation of Bioactive Compounds in Wild Thyme (Thymus serpyllum L.) Herbal Dust-Chemical Profile, Antioxidant and Antimicrobial Activity and Comparison with Conventional Techniques.

The aim of this study was to provide a chemical profile and determine the antioxidant and antimicrobial activity of the essential oil (EO) and lipid extracts of Thymus serpyllum L. herbal dust obtained via conventional (hydrodistillation (HD) and Soxhlet extraction (SOX)) and novel extraction techniques (supercritical fluid extraction (SFE)). In addition, a comparative analysis of the chemical profiles of the obtained EO and extracts was carried out, as well as the determination of antioxidant, antibacterial and antifungal activity of the lipid extracts. According to the aforementioned antioxidant and antimicrobial activities and the monoterpene yield and selectivity, SFE provided significant advantages compared to the traditional techniques. In addition, SFE extracts could be considered to have great potential in terms of their utilization in the pharmaceutical and cosmetic industries, as well as appropriate replacements for synthetic additives in the food industry.

The function for estimating the separation efficiency of the wheat flour milling process.

Considering the significant differencies between the chemical composition of the kernel layers, distribution of chemical compounds in intermediate, final and subproducts of the milling process come as a result of the level of dissociation achieved during the milling process. These differences serve as a basis for the mill process control. Ash determination is probably the most widely used tool while even greater differencies exist in cellulose and especialy starch content. In this work efficiency function has been defined and used to evaluate the relative efficiency of the separation of endosperm from the outer pericarp leyers of the kernel. It is based on quantity rates (flour extraction and subproducts yield) and qulitative analyses (starch and cellulose content in the wheat, flour and subproducts).

Optimization of rheological characteristics of bread dough supplemented with defatted wheat germ.

Optimization of bread dough formulation with defatted wheat germ (DWG) in terms of dough rheological properties was the objective of this study. Fractional factorial design 2V5-1 was applied in order to investigate influence of DWG granulation (<150 µm and 150-1000 µm), DWG content (10 and 20%), addition of gluten (0 and 5%), ascorbic acid (0.004 and 0.008%) and combined improver (0.1 and 0.3%) on farinograph and extensograph parameters. Responsive variables were water absorption and the degree of softening, obtained by farinograph, and resistance to extension and extensibility as well as their ratio, obtained by extensograph analysis. Gluten addition expressed dominant positive effect on water absorption and the degree of softening. The most pronounced negative effect on dough resistance exhibited DWG content (contribution of 57%). The combination of DWG with smaller particle size and 5% of gluten addition increased both resistance and extensibility, but R/E ratio was not affected. The optimal values for DWG granulation, DWG content, gluten content, ascorbic acid content and combined improver content were: < 150 µm, 14.24%, 4.83%, 0.004% and 0.1%, respectively, while predicted values for desired responsible variables were: water absorption 65.90%, degree of softening 84.05 FU, resistance 301.30 EU, extensibility 108.55 mm and R/E 2.5.

Phytochemical Composition of Different Red Clover Genotypes Based on Plant Part and Genetic Traits.

Red clover (Trifolium pratense L.) is an important legume that is also known as a rich source of isoflavones, which are compounds with mild estrogenic activity. Therefore, this plant is often used as a raw material in the production of dietary supplements recommended in menopause. Many factors can influence isoflavone content, but those genetically related are considered to be the most important. Therefore, the aim of this study was to evaluate the phytochemical profile of different plant parts of 30 red clover genotypes grouped according to ploidy and country of seed origin by analyzing the content of dominant isoflavones, total phenolic content (TPC) and antioxidant activity. It was found that there are significant differences in the examined traits among plant parts. Red clover leaves had the highest total isoflavone content, with biochanin A as the dominant compound, while flower extracts had the highest TPC and antioxidant activity. Diploid and tetraploid genotypes were significantly different concerning the content of daidzein, genistein, formononetin and TPC with higher quantities in tetraploid samples. On the other hand, seed origin was not a useful separating factor for the analyzed samples. The results of this research indicate that ploidy, as a previously poorly studied factor, could influence isoflavone content in red clover.

Polyphenols Recovery from Thymus serpyllum Industrial Waste Using Microwave-Assisted Extraction-Comparative RSM and ANN Approach for Process Optimization.

The aim of this study was to valorize Thymus serpyllum L. herbal dust, the particular fraction distinguished as industrial waste from filter-tea production. This work demonstrated comparable analysis considering model fitting, influence analysis and optimization of microwave-assisted extraction (MAE) of bioactive compounds from the aforementioned herbal dust using face-centered central composite experimental design within the response surface methodology (RSM), as well as artificial neural networks (ANN). In order to increase yield and amount of compounds of interest and minimize solvent, time and energy consumption, the ethanol concentration (45, 60 and 75%), extraction time (5, 12.5 and 20 min), liquid-solid ratio (10, 20 and 30 mL/g) and irradiation power (400, 600 and 800 W) were used as independent variables. Total extraction yield (Y), total phenols yield (TP), as well as antioxidant activity parameters obtained by DPPH and ABTS assays, were selected as responses. It could be concluded that the MAE technique is an efficient approach for the extraction of biologically active compounds from T. serpyllum herbal dust, which represents a high-value source of natural antioxidants with great potential for further use in various forms within different branches of industry.

Physico-chemical and microbiological changes during the cabbage hybrid bravo heads fermentation: Salt, temperature and starter culture influence.

The influence of temperatures (18, 22 and 26 °C), salt (60, 70 and 80 g/kg) and starter culture (0, 0.025 and 0.050 g/kg) on physico-chemical and microbiological changes during fermentation in cabbage heads were investigated. The experiment was set up in industrial conditions, samples were taken after 0, 5, 12, 27 and 62 days in order to determine the changes in color, texture, biogenic amines content, microbiological parameters, pH, aw, total sugar content, total acidity and salt content. Analysis of variance and Principal component analysis were applied to get a better overview of differences between samples and the similarities between different fermentation conditions. Significant color changes and softening of cabbage tissue did not occurred during the entire fermentation process. Cadaverine was not detected in samples containing starter culture, also the results were in range for maximum allowed putrescine and cadaverine doses for all cabbage samples. Total number of molds increased, contrary to number of yeasts on the last examined day in comparison with raw cabbage sample. Enterobacteriaceae were not detected after 5th fermentation day, while sharp increase of lactic acid bacteria number occurred until 12th day, and on the 12th fermentation day was in range of 7.82 to 9.84 log cfu/g. The fermentation process led to decrease in pH, aw and total sugar content, meanwhile total acidity 0.54%-0.89% and salt content 2.08%-3.19% in the cabbage heads increased, in comparison with raw sample where results for total acidity and salt content were 0.13% and 0.05%, respectively. Additionally, according Principal component analysis, temperature of fermentation had the greatest influence on the fermentation process, followed by the application of starter culture and then concentration of added salt.

Supercritical Fluid Extraction Kinetics of Cherry Seed Oil: Kinetics Modeling and ANN Optimization.

This study was primarily focused on the supercritical fluid extraction (SFE) of cherry seed oil and the optimization of the process using sequential extraction kinetics modeling and artificial neural networks (ANN). The SFE study was organized according to Box-Behnken design of experiment, with additional runs. Pressure, temperature and flow rate were chosen as independent variables. Five well known empirical kinetic models and three mass-transfer kinetics models based on the Sovová's solution of SFE equations were successfully applied for kinetics modeling. The developed mass-transfer models exhibited better fit of experimental data, according to the calculated statistical tests (R2, SSE and AARD). The initial slope of the SFE curve was evaluated as an output variable in the ANN optimization. The obtained results suggested that it is advisable to lead SFE process at an increased pressure and CO2 flow rate with lower temperature and particle size values to reach a maximal initial slope.

Antioxidant and enzyme-inhibitory activity of peppermint extracts and essential oils obtained by conventional and emerging extraction techniques.

Peppermint is widely used medicinal plant with distinguished bioactive potential, therefore, the aim of present work was to develop novel peppermint extracts with high activity by application of traditional and emerging separation techniques. Conventional hydrodistillation and microwave-assisted hydrodistillation (MWHD) were applied for recovery of essential oil (EO), while organic solvent extraction using Soxhlet apparatus, microwave-assisted and ultrasound-assisted process and supercritical fluid extraction (SFE) were applied for non-selective recovery of peppermint lipophilic extracts. Extracts were characterized in terms of terpenoids profile with special emphasis on content of major compounds (mentol, menthone, isomenthol and eucalyptol). Antioxidant activity (DPPH, ABTS, CUPRAC, FRAP, chelating and phosphomolybdenum assay) and enzyme-inhibitory assays (acetylcholinesterase, butyrylcholinesterase, tyrosinase, amylase and glucosidase inhibition) were used for screening of peppermint bioactivity. MWHD was recognized as alternative for traditional process in EO recovery, while SFE extracts were useful for green production of solvent-free peppermint extracts rich in terpenoids and other lipophilic bioactives.

Defatted wheat germ application: Influence on cookies' properties with regard to its particle size and dough moisture content.

The introduction of agro-food industry by-products rich in bioactive compounds represents major challenge in food industry sector. The influence of wheat germ particle size (<150 µm, 150-1000 µm, and 800-2000 µm), wheat germ content (5, 10, and 15%), and dough moisture content (20, 22, and 24%) on chemical, textural, and sensory characteristics of cookies was investigated using the Box-Behnken experimental design. The substitution of wheat flour with wheat germ increased the protein, fat, mineral, and fiber content of the cookies. The particle size of wheat germ affected the textural properties of cookies. As the particle size of wheat germ increased, the hardness of cookies decreased. The color of the cookie was most influenced by the interaction of dough moisture content and wheat germ particle size. Wheat germ level up to 15% had no significant effect on the sensory characteristics of cookies. A suitable combination of defatted wheat germ level, its particle size, and dough moisture content can improve the nutritional value of cookies, without causing a negative effect on the cookies' sensory characteristics.

Chemometric optimization of the robustness of the near infrared spectroscopic method in wheat quality control.

A chemometric approach was applied for the optimization of the robustness of the NIRS method for wheat quality control. Due to the high number of experimental (n=6) and response variables to be studied (n=7) the optimization experiment was divided into two stages: screening stage in order to evaluate which of the considered variables were significant, and optimization stage to optimize the identified factors in the previously selected experimental domain. The significant variables were identified by using fractional factorial experimental design, whilst Box-Wilson rotatable central composite design (CCRD) was run to obtain the optimal values for the significant variables. The measured responses included: moisture, protein and wet gluten content, Zeleny sedimentation value and deformation energy. In order to achieve the minimal variation in responses, the optimal factor settings were found by minimizing the propagation of error (POE). The simultaneous optimization of factors was conducted by desirability function. The highest desirability of 87.63% was accomplished by setting up experimental conditions as follows: 19.9°C for sample temperature, 19.3°C for ambient temperature and 240V for instrument voltage.

Optimization of thiamethoxam adsorption parameters using multi-walled carbon nanotubes by means of fractional factorial design.

The aim of this work was to evaluate significant factors affecting the thiamethoxam adsorption efficiency using oxidized multi-walled carbon nanotubes (MWCNTs) as adsorbents. Five factors (initial solution concentration of thiamethoxam in water, temperature, solution pH, MWCNTs weight and contact time) were investigated using 2V(5-1) fractional factorial design. The obtained linear model was statistically tested using analysis of variance (ANOVA) and the analysis of residuals was used to investigate the model validity. It was observed that the factors and their second-order interactions affecting the thiamethoxam removal can be divided into three groups: very important, moderately important and insignificant ones. The initial solution concentration was found to be the most influencing parameter on thiamethoxam adsorption from water. Optimization of the factors levels was carried out by minimizing those parameters which are usually critical in real life: the temperature (energy), contact time (money) and weight of MWCNTs (potential health hazard), in order to maximize the adsorbed amount of the pollutant. The results of maximal adsorbed thiamethoxam amount in both real and optimized experiments indicate that among minimized parameters the adsorption time is one that makes the largest difference. The results of this study indicate that fractional factorial design is very useful tool for screening the higher number of parameters and reducing the number of adsorption experiments.

Intravitreal bevacizumab injection alone or combined with macular photocoagulation compared to macular photocoagulation as primary treatment of diabetic macular edema.

BACKGROUND/AIM: Within diabetic retinopathy (DR), diabetic macular edema DIE) is one of the leading causes of the loss of visual acuity. The aim of this study was to determine the efficacy of the intravitreal vascular endothelial growth factor (VEGF) inhibitor application alone or combined with macular focal/grid lasephotocoagulation compared with laser treatment alone. METHODS: This prospective randomized clinical trial included 72 patients (120 treated eyes) with varying degrees of DR and DME. The DME treatment included intravitreal VEGF inhibitor bevacizumab (Avasting) application, with and without laser treatment. Bevacizumab (1.25 mg/0.05 mL) was administered intravitreally in 4-6-week intervals. Laser is applied 4-6 weeks after last dose of the drug as a part of combined treatment, or as the primary treatment. RESULTS: The mean reduction in central macular thickness (CMT) for the eyes (n = 31) treated with bevacizumab alone was 162.23 .rm, for the eyes (n = 53) treated with combined treatment the mean reduction in CMT was 124.24 pm, both statistically significant at p < 0.001. Laser macular photocolagulation as a part of combined treatment (in 53 eyes) significantly contributed to the CMT reduction, based on the paired t-test results (366.28 vs. 323.0 pLm at p < 0.05). In our study, the mean visual acuity improvement of 0.161 logMAR was achieved in the group of eyes treated with bevacizumab alone, and 0.093 logMAR in the group with combined treatment, both statistically significant atp < 0.05. The effect of laser photocolagulation alone on visual acuity and'CMT was not statistically significant. CONCLUSION: Treatment with bevacizumab alone or within combined treatment is more effective in treating DME than conventional macular laser treatment alone, both anatomically and functionally.