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Estimation of the storage properties of rapeseeds using an artificial neural network
No full textRapeseed losses during storage can lead to undesirable difficulties in oil and biodiesel production. In this paper, three artificial neural networks were created to anticipate the main quality parameters of thirteen rapeseed varieties - cultivars and hybrids (Brassica napus L.) - during drying and storage. The varieties, drying temperature, air velocity and drying time were used as inputs to the artificial neural network model to predict the changes in seed weight and moisture during the drying process. The moisture diffusivity and activation energy of the investigated rapeseed varieties were determined under convective drying. For the experiment, an on-site drying system was used at 40, 60 and 80 degrees C drying air temperature. The effective diffusivity ranged from: 7.947.10(-10) to 1.459.10(-8) m(2)/s (first drying period) and 4.716.10(-10) to 8.611.10(-9) m(2)/s (second drying period). The predicted Arrhenius constant and activation energy ranged from 17.169 to 42.546 kJ/mol (first drying period) and from 31.261 to 50.474 kJ/mol (second drying period). Seed oil content, free fatty acids and thousand seed weight were determined after drying at different temperatures and after 12 months of storage under the three different storage conditions. To predict these parameters after storage time, a multilayer perceptron model with three layers (input, hidden and output) for three artificial neural networks (ANNs) was used for modelling using the implemented drying parameters (such as: variety, drying temperature, air velocity and drying time, along with initial oil and free fatty acid content and storage type) were used. The prediction of the developed model was accurate enough for the prediction of the output parameters. The coefficients of determination ranged from 0.965 to 0.998 when predicting the weight and moisture of the rapeseed during the drying process and the oil and free fatty acid content and thousand grain weights after the 12 months storage period
Effective bioactive systems for nitrate removal from building materials
No full textBioactive system for reducing nitrate content in brick and limestone was developed using mineral poultice and aerobic denitrifier Pseudomonas stutzeri cells. The efficiency of the systems with P. stutzeri D1 was considerably higher compared with the reference strain for the both examined materials. After 9 days of application of the bioactive systems, the biocleaning efficiency was approximately 70% for both strains on the brick surface, while the efficiency in the depth was 72% and 95% using the reference strain and natural isolate, respectively. Artificial neural network efficiency prediction showed good prediction according to material layer depth, time, and bacteria type
Valorization potential of Plantago major L. solid waste remaining after industrial tincture production: Insight into the chemical composition and bioactive properties
No full textPurpose Herbal residues from the production and processing of medicinal plants are usually discarded as waste material. Plantago major is an edible plant, traditionally used for medicinal purposes, having wide application in the pharmaceutical and cosmetics industry, usually in the form of liquid extracts and tinctures. In this work, extracts of P. major leaves waste remaining after industrial tincture production and dried leaves used initially for tincture production were investigated and compared. Methods The chemical composition was obtained by FTIR analysis, whereas polyphenolic profile was assessed by HPLC. Antioxidant activity, sun protection factor (SPF), cytotoxic activity against colon carcinoma (HCT116) and melanoma (Hs294T) human cell lines as well as antistaphylococcal activity against S. aureus ATCC strains and one clinical isolate were also evaluated. Results FTIR analysis revealed wider chemical diversity in waste samples than in initial plant material. Among detected phenolics, chlorogenic acid, luteolin, and rutin were the most abundant in all extracts, whereas luteolin was even higher in the waste. Waste extracts had a significantly lower sun protection factor (SPF) when compared to initial dried leaves. On the contrary, cytotoxic activity of waste extracts against tested human cell lines were more efficient when compared to initial dried leaves, which can be attributed to the higher luteolin content in tincture residues. Both waste and initial dried leaves extracts exhibited antibacterial activity against all tested S. aureus strains at higher tested concentrations. Conclusion P. major waste remaining after industrial tincture production represents high-value material with great valorization potential. Graphic abstrac
Shelf life stability of osmodehydrated white cabbage: PCA analysis
No full textCilj ovog rada je da se analizira održivost osmotski dehidriranog belog kupusa. Hibrid "Bravo" je analiziran i podvrgnut osmotskom tretmanu u tri različita osmotska rastvora. Rastvor S1 je zasićen rastvor sharoze i natrijum hlorida u vodi, rastvor S2 je mešavina rastvora S1 i melase šećerne repe u odnosu 1:1 i rastvor S3 je čista melasa sa sadržajem suve materije od 84,05 %. Nakon osmotskog tretmana kupus je pakovan u poliamid/polietilen kese na laboratorijskoj pakerici sa vakuum zaptivanjem uz prethodno uvođenje modifikovane atmosfere u mešavini gasova od 40:60/ CO2:N2 (atmosfera 1) i 80:20/CO2:N2 (atmosfera 2). Tokom 90 dana skladištenja praćeni su mikrobiološki i hemijski parametri, instrumentalno merenje boje i senzorska svojstva. Kod kupusa dehidriranog u sva tri rastvora zabeležen je pad sadržaja ukupnih kiselina i posledično rast pH vrednosti tokom skladištnja, naročito kod rastvora S3. Pakovanje u MAP bez prisutva vazduha dovelo je do pada ukupnog broja mikroorganizama dok je rast kvasaca i plesni u potpunosti inhibiran. Tokom skladištenja dolazi do sukcesivnog smanjenja sadržaja L-askorbinske kiseline u kupusu i retencija je najveća nakon osmotskog rastvora S2 i iznosi 15,25 % nakon skladištenja od 90 dana. Senzorska analiza je pokazala zadovoljavajući kvalitet osmotski dehidriranog kupusa nakon 90 dana skladištenja. PCA analiza je uspešno opisala eksperimentalne rezultate. PCA analiza se može primenjivati u procesu optimizacije osmotskog tretmana u cilju dobijanja željenog kvaliteta finalnog proizvoda i efikasno koristiti u prediktivne svrhe.The aim of the present work is to determine the shelf life of osmodehydrated white cabbage in three different osmotic solutions. During 90 days of storage, chemical and color parameters were analysed together with the sensory acceptance and microbiological profile of the osmotic treated (OT) cabbage. Hybrid "Bravo" was considered within this research because of its high yield and wide cultivation in the Province of Vojvodina. Solutions of sucrose and chloride were applied so as sugar beet molasses in OT. OT cabbage was packed in MAP with variation in a gas mixture of 40:60/ CO2:N2 (atmosphere 1) and 80:20/CO2:N2 (atmosphere 2). The shelf-life evaluation had shown good sensorial acceptance and satisfying microbiological quality. The obtained principal component analysis (PCA) was able to present the experimental results. The PCA analysis is easy to implement and could be effectively used for predictive optimization of the osmotic treatment
Kinetics of the Release of Nicotinamide Absorbed on Partially Neutralized Poly(acrylic-co-methacrylic acid) Xerogel under the Conditions of Simultaneous Microwave Heating and Cooling
No full textThe kinetics of release of nicotinamide (NIAM) that was absorbed on partially neutralized poly(acrylic-co-methacrylic) (PAM) xerogel/hydrogel, under the conditions of simultaneous microwave heating and cooling (SMHC) were examined. The kinetics curves of NIAM release into an aqueous solution at temperatures of 308-323 K were recorded. By applying the model-fitting method (MFM), it was found that the kinetics of NIAM release can be modeled by a kinetic model of a first-order chemical reaction. The values of the release rate constants (k(M)) at different temperatures were calculated, and their values were found to be within the range 8.4 10(-3) s (-1)-15.7 10(-3) s(-1). It has been established that the Arrhenius equation was valid even in the conditions of SMHC. The values of the kinetic parameters (activation energy (Ea) and pre-exponential factor (A) of the NIAM release process adsorbed on PAM xerogel/hydrogel were calculated as follows: Ea = 25.6 kJ/mol and ln (A/s(-1)) = 5.21. It has been proven that the higher value of the rate constant at SMHC in relation to CH is not a consequence of the overheating of the reaction system or the appearance of "hot-points". The values of change of the enthalpy of activation (Delta H*) and the change of entropy of activation (Delta S*) were calculated as follows: Delta H* = +23.82 kJ/mol and Delta S* = -201.4 J/mol K. The calculated higher values of the kinetic parameters and thermodynamic parameters of activation are explained by the formation of a specific activated complex under SMHC, whose structure and degree of order are different than in the one formed under CH
Impact of variability in protein content of sunflower meal on the extrusion process and physical quality of the extruded salmonid feed
No full textThis study aimed to characterize sunflower meal (SFM) with a protein content of similar to 370 g/kg per dry matter (SFM1) and its two high protein fractions obtained by air classification (SFM2 and SFM3 containing 430 and 490 g/kg of protein per dry matter, respectively) as aqua feed ingredient, based on their functional properties that are important for extrusion processing. A mixture design was applied, varying the levels of SFM1, SFM2 and SFM3 from 88.2 to 267.2 g/kg in dry feed mixes intended for trout. SFM1 presence in the diet caused higher flow resistance of the material in the extruder barrel, and thus higher energy consumption compared to extrusion of diets containing SFM2 and SFM3. SFM1 suppressed the product expansion but induced formation of hollow and brittle pellets with high oil absorption capacity. Increase in protein content of SFM led to more compact structure, resulting in increased hardness, durability, water stability, and decreased oil leakage. Besides better nutritional quality, air classified low fiber SFMs prevail over basic SFM also in terms of their functionality. Still, presence of high fiber SFM could improve physical attributes of pellets in terms of their oil absorption capacity, important characteristic for salmonid feeds. Practical Applications: Identification of functional properties of a certain ingredient is an important task when evaluating a novel ingredient in fish feed industry. This study assessed functionality of dehulled high protein sunflower meals, obtained by air classification, in the aqua feed extrusion process. The inclusion of sunflower meal with protein content higher than 400 g/kg, at level up to 200 g/kg, increased rigidity, water stability and oil retention ability of pellets, while decreased input of mechanical energy during extrusion. The contemporary aqua feed industry is oriented toward low fishmeal/high plant-based diets. In this respect the outcomes of this study indicate that dehulled sunflower meal could be used as an alternative protein source to fishmeal in aqua feed from technological standpoint with beneficial effects on process parameters and without impaired effects on pellet physical quality
Evaluation of tocopherols and tocotrienols in Albanian cultivars
No full textWheat is a major component in the human diet with an impact on nutritional health due to its significant intake. The aim of this study was to evaluate the quality of Albanian wheat by analysing chemical and nutrition parameters and understanding the health impact of the components in wheat flour. Five winter wheat cultivars grown during the year 2017-2018 on experimental fields of Agriculture Technology Transfer Center (ATTC) in Lushnja were analysed. Protein content (%N x 5.7) was determined by the Kjedahl method and lipid content was evaluated by Soxhlet extraction method utilizing n-hexane as solvent. The starch content was analyzed following the Megazyme Starch determination procedure (Megazyme International, Ireland, Ltd). The determination of the total content of tocopherols (TP) and tocotrienols (TT) in the five wheat cultivars was carried out using the High Performance Liquid Chromatography (HPLC) analysis. A descriptive statistical analysis was performed for result elaboration. The analysis of variance (ANOVA) and Principal Component Analysis (PCA) was performed using StatSoft Statistica 10.0 software and the significant differences were calculated according to post-hoc Tukey’s (HSD) test at p ˂ 0.05. All cultivars showed higher level of protein content ranging from 11.39% to 12.38% and the starch content ranging from 58% to 62%. Statistical results indicated that the protein content was significantly affected by the wheat cultivars. ɑ-Tocopherol and ß-tocotrienol were the most abundant compounds in all samples, ranging, from 9.8 mg/kg DW to 15.6 mg/kg DW and from 8.1 mg/kg to 12.7 mg/kg DW, respectively. The daily requirement of vitamin E calculated in whole flour ranges from 14.7% to 26%.By selecting the suitable wheat cultivars with high vitamin E content, we can contribute to increasing the content of vitamin E in Albanian wheat flour and supporting the problems of vitamin E deficiency in the human diet
Helichrysum italicum (Roth) G. Don Essential Oil from Serbia: Chemical Composition, Classification and Biological Activity-May It Be a Suitable New Crop for Serbia?
No full textH. italicum essential oil (EO) is one of the most popular ingredients utilized by the cosmetic industry, and it is also used as natural antioxidant and as a value-added ingredient in food products. The chemical composition of the EO H. italicum cultivated in Serbia was analyzed by gas chromatography-mass spectrometry. The quantitative structure-retention relationship was used to predict the retention indices of the EO constituents acquired by GC-MS data, applying five molecular descriptors selected by factor analysis and a genetic algorithm. Also, antimicrobial activity, and biological activity by four common antioxidant tests (DPPH and ABTS assays, reducing power, and beta-carotene bleaching test), and in vitro antihyperglycemic and anti-inflammatory capacities were evaluated. A total of 70 EO constituents were detected, of which 17 (8.5%) could not be identified. The H. italicum EO in this study belonged to gamma-curcumene chemotype. The coefficients of determination reached the value of 0.964, demonstrating that this model could be used for prediction purposes. All applied tests showed that H. italicum EO possesses good biological activity and an interesting chemical composition. Therefore, the EO of H. italicum grown in Serbia has a potential to be used in food, cosmetic, and pharmaceutical products
Anethum graveolens: Chemical composition, cultivation and uses
No full textFamily Apiaceae is very big, with more than 3.700 species distributed throughout the world. There are specific umbeliferous flowers and odor characteristic for each individual species. Anethum graveolens L. is one of them and due to its herbal warm-spicy odor it is often used as spice in cooking, as dry seed and fresh or dry leaves. Apart from this, it is one of the most popular traditional remedies in many countries. Research has proven numerous positive effects of this plant on the human body, therefore phytoremedies with dill addition are formulated. It is also a very popular nutraceutical. Furthermore, in recent years, bioactive potential of many medicinal and aromatic plants is investigated for their application in organic agriculture, for improving biodiversity and as a biopesticide. Constituents in dill responsible for all this are essential oil with carvone and limonene and phenolic compounds. Due to great demand for highquality raw material, A. graveolens is mainly cultivated. Postharvest processing is also very important for maintaining high-quality of raw material. Postdistillation waste material can also be useful, especially as feed
The Effects of a Meldonium Pre-Treatment on the Course of the Faecal-Induced Sepsis in Rats
No full textSepsis is a life-threatening condition caused by the dysregulated and overwhelming response to infection, accompanied by an exaggerated pro-inflammatory state and lipid metabolism disturbance leading to sequential organ failure. Meldonium is an anti-ischemic and anti-inflammatory agent which negatively interferes with lipid metabolism by shifting energy production from fatty acid oxidation to glycolysis, as a less oxygen-demanding pathway. Thus, we investigated the effects of a four-week meldonium pre-treatment on faecal-induced sepsis in Sprague-Dawley male rats. Surprisingly, under septic conditions, meldonium increased animal mortality rate compared with the meldonium non-treated group. However, analysis of the tissue oxidative status did not provide support for the detrimental effects of meldonium, nor did the analysis of the tissue inflammatory status showing anti-inflammatory, anti-apoptotic, and anti-necrotic effects of meldonium. After performing tissue lipidomic analysis, we concluded that the potential cause of the meldonium harmful effect is to be found in the overall decreased lipid metabolism. The present study underlines the importance of uninterrupted energy production in sepsis, closely drawing attention to the possible harmful effects of lipid-mobilization impairment caused by certain therapeutics. This could lead to the much-needed revision of the existing guidelines in the clinical treatment of sepsis while paving the way for discovering new therapeutic approaches