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Physicochemical Changes of Heat-Treated Corn Grain Used in Ruminant Nutrition
No full textSimple Summary Whole grain with an intact pericarp is highly resistant to digestion by ruminants and external processing is required. Cereal grain is processed using different combinations of heat, moisture, time, and mechanical action. As a result of processing, starch becomes more available to both ruminal microbial and pancreatic enzymes. In animal science literature, there is a lack of data regarding the physicochemical properties of starchy materials prior to and after the application of processing treatments, as well as the connection to biological responses of animals in nutritional studies. Therefore, the aim of the present study was to quantitatively represent physicochemical properties of raw and heat-treated corn starch using an in vitro methodology that is commonly used by food scientists. The heat treatments examined were pelleting, steam flaking, micronization, and extrusion of corn. The obtained results indicated significant differences in gelatinization, hydration, and pasting properties of corn starch depending on the heat treatment applied. Future research should aim for the determination of rumen starch degradation traits and possible correlations with the present results. Cereal grain is processed using different combinations of heat, moisture, time, and mechanical action in order to improve its digestibility. The objective of the present research was to quantitatively represent the physicochemical properties of raw and processed starch using an in vitro methodology, as well as to describe the changes that occurred after heat treatment, such as pelleting, steam flaking, micronization, and extrusion of corn. Based on the obtained results, pelleting, steam flaking, and micronization can be considered as mild heat treatment methods, whereas extrusion proved to be a severe heat treatment method. Analysis of functional and pasting properties implied a possible interaction between the degraded components in the steam-flaked sample, as well as in the micronized sample, through to a lesser extent. Additionally, the occurrence of dextrins was noted after extrusion. The obtained results indicate the existence of significant differences in the physicochemical properties of corn starch depending on the heat treatment applied, which could possibly affect rumen starch degradation traits
The Effects of Winter Cover Crops on Maize Yield and Crop Performance in Semiarid Conditions-Artificial Neural Network Approach
No full textMaize is the most widespread and, along with wheat, the most important staple crop in the Republic of Serbia, which is of great significance for ensuring national food security. With the increasing demand for food and forage, intensive agricultural practices have been adopted in the maize production systems. In this direction, considerable research efforts have been made to examine the effects of different types of cover crops as a green manure on maize productivity; however, no consistent conclusions have been reached so far. Therefore, the objective of the present study is to examine the possibility of predicting the effects of winter cover crops (CC) integrated with different management practices on the morphological traits, yield, and yield components of maize. The experiment was carried out on chernozem soil from 2016 to 2020 as a randomized complete block design arranged as a split-split-plot with three replicates. The pea as a sole crop (P) and the mixture of pea and triticale (PT) are sown as winter CC with the following subplots: (i) CC used as green manure, and (ii) CC used as forage and removed before maize sowing. The artificial neural network is used for exploring nonlinear functions of the tested parameters and 13 categorical input variables for modeling according to the following factors: CC, way of using CC, N fertilization, and year. The computed maximums of plant height, number of leaves, number of internodes, plant density, number of ears, grain yield, 1000-grain weight, hectolitre weight, dry matter harvest residue, harvest index, leaves percentage, stems percentage, and ears percentage are as follows: 232.3 cm; 9.7; 10.2; 54,340 plants ha(-1); 0.9; 9.8 t ha(-1); 272.4 g; 67.0 kg HL-1; 9.2 t ha(-1); 0.52; 18.9%; 36.0%, and 45.1%, respectively. The optimal result is obtained with peas used as green manure, with 50 kg N ha(-1) and in the climatic conditions of 2018. Consequently, maize production under subsequent sowing periods can be successfully optimized by adapting selected management options for higher yield accomplishment
Celery Root Phenols Content, Antioxidant Capacities and Their Correlations after Osmotic Dehydration in Molasses
No full textThe osmotic dehydration (OD) of celery root in sugar beet molasses was studied at three temperatures (20, 35, and 50 degrees C) and three immersion periods (1, 3, and 5 h) in order to examine the changes in antioxidant potential and phenolic profile of celery root throughout the process. The antioxidant capacity (AOC) of dehydrated samples was evaluated by spectrophotometric and polarographic assays, the total phenolic content by the Folin-Ciocalteu method, and the individual phenolic compounds by HPLC-DAD. As a result of OD in molasses, the AOC and phenols content in samples increased proportionally to the augmentation of temperature and the immersion time. Vanillic acid, syringic acid, and catechin were detected in dehydrated samples as a result of transfer from molasses. Compared to fresh celery root, the content of identified phenols in osmodehydrated samples was improved from 1.5 to 6.2 times. Strong correlations between applied assays were obtained, except for the DPPH. Based on the correlation analysis chlorogenic acid, gallic acid, chrysin, catechin, and kaempferol showed the greatest contribution to the overall AOC of osmodehydrated celery root. Molasses, an agro-industrial waste from sugar production, could be valorized as a valuable osmotic solution
Chemical Composition, Antioxidant, and Antimicrobial Activity of Dracocephalum moldavica L. Essential Oil and Hydrolate
No full textSteam distillation was used for the isolation of Dracocephalum moldavica L. (Moldavian dragonhead) essential oil (DMEO). This aromatic herbaceous plant is widespread across the Northern Hemisphere regions and has been utilized in health-improving studies and applications. In addition to the DMEO, the hydrolate (DMH), a byproduct of the distillation process, was also collected. The DMEO and DMH were analyzed and compared in terms of their chemical composition, as well as their in vitro biological activities. The main component in DMEO was geranyl acetate, while geranial was dominant in DMH. The DMEO demonstrated better antioxidant and antimicrobial activities compared with the DMH against Staphylococcus aureus, Escherichia coli, Salmonella Typhimurium, and Listeria monocytogenes, which represent sources of food-borne illness at the global level. The DMEO and DMH show promise as antioxidant and antimicrobial additives to various products
Obtaining Fat-Soluble Pigments-Carotenoids from the Biomass of Chlorella Microalgae
No full textThe aim of this study was to use a directed mode of cultivation of the microalgae Chlorella for biomass production, followed by the subsequent extraction of carotenoids. The effect of a stress inducer of carotenogenesis (hydrogen peroxide) and a growth stimulator (pyridoxine, vitamin B6) on the accumulation of photosynthetic pigments by the biomass of the microalga C. vulgaris BIN in the process of directed cultivation was studied. It was revealed that the combination of these additives in the culture medium increases the content of chlorophylls and carotenoids in the biomass twofold compared to the control sample. The preliminary activation of the biomass by high-speed ultra-homogenization (a rotor rotation range from 6000 to 12,000 rpm) was also investigated. Using ultrasound extraction, the pigment complex was isolated from the activated biomass. The saponification and subsequent neutralization of carotenoids were carried out in an inert medium. The resulting sample contained carotenoids in the amount of 52 +/- 3 mg/mL. The chemical profile of the carotenoids in the biomass of the microalga Chlorella vulgaris BIN was also established. The major carotenoid was lutein (45%), followed by fucoxanthin (12%) and beta-carotene (4.3%). The oil extract of the carotenoids may be used for the further production of a microencapsulated product with the aim of targeted delivery to the lower parts of the gastrointestinal tract
Comparative Study of the Essential Oil and Hydrosol Composition of Sweet Wormwood (Artemisia annua L.) from Serbia
No full textThe most abundant volatile compounds of sweet wormwood (Artemisia annua L.) essential oil were artemisia ketone (25.4 %) and trans-caryophyllene (10.2 %), followed by 1,8-cineole, camphor, germacrene D and beta-selinene. The major volatile compounds in the hydrosol were camphor (25.1 %), 1,8-cineole (20.5 %) and artemisia ketone (10.7 %), followed by trans-pinocarveol and yomogi alcohol. Tested essential oil was rich in oxygenated monoterpenes and sesquiterpene hydrocarbons, while the former were identified as the major class of volatile compounds in the hydrosol, due to higher water solubility. Classification of all sweet wormwood chemotypes, according to essential oil composition, in available literature (17 studies and 61 accessions) could be done according to four chemotypes: artemisia ketone+artemisia alcohol (most abundant), artemisia ketone, camphor and nonspecific chemotype. According to this classification, essential oil of sweet wormwood from this study belongs to artemisia ketone (content varied between 22.1 and 55.8 %). Bearing in mind that hydrosols are a by-product of industrial production of essential oils, and the fact that sweet wormwood hydrosol has high contents of camphor, 1,8-cineole and artemisia ketone, there is a great potential for the use of this aromatic plant primary processing waste product as a water replacement in cosmetic industry, beverages flavoring, for food preservation, as well as in post-harvest pre-storage treatments in organic agriculture
Solid biofuels properties of Miscanthus X giganteus cultivated on contaminated soil after phytoremediation process
No full textFollowing the objectives of the 2030 climate and energy framework as well as the European Green Deal strategy to 2050, renewable energy sources have been defined as an important factor in the process of climate change mitigation. Renewable energy sources are the basis of the aspirations of the EU to achieve low-carbon energy selfsufficiency. Under the classification of renewable energy sources biomass obtained by cultivating energy crops is also included. In order to avoid collisions between energy production and food/feed production, the cultivation of energy crops should be based on marginal soils, which also include soil contaminated by heavy metals. The use of energy crops in the process of phytoremediation is a multifunctional methodology that manifests itself through the cleaning of contaminated soil with the biomass production. The usefulness of using certain biomass types in the ignition process is valorized by the determination of biomass properties. The aim of this three years' investigation was to analyze the biomass quality (proximate and ultimate analysis, calorific values, micro and macroelements) of Miscanthus x giganteus cultivated on soils with three cadmium (Cd) and mercury (Hg) contamination levels. All analyzed parameters, except Cd, K and Cr, are compatible with or have only expected differences from the literature data and/or ISO 17225-1:2014 norm for solid biofuels. The values of ash, volatile matter, C content and lower heating value as one of the most important energy parameters, are in the range 1.35-3.66%, 86.28-90.39%, 46.34-49.91% and 16.24-16.93 MJ/kg respectively
Biological Profiling of Essential Oils and Hydrolates of Ocimum basilicum var. Genovese and var. Minimum Originated from Serbia
No full textThe genus Ocimum has many species that are used to treat diverse kinds of illnesses and sicknesses from ancient times. One of them, Ocimum basilicum L., commonly known as basil, has a vital role due to its various medicinal goods. It is best known as a plant with pharmacological activities, but also as an antioxidant, antimicrobial, and larvicidal agent. Although it has been traditionally used in Serbia in traditional medicine for centuries as an insecticidal, antibacterial, and antifungal plant as well as a traditional culinary plant, none of the O. basilicum varieties have been commercialised until today. There are significant numbers of information across the world that oils and by-products are part of the global market, but no references to the essential oil composition of Serbian plants were found. Therefore, the objective of this work was to evaluate the antioxidant and antimicrobial potentials of essential oil and hydrolate of two different varieties: O. basilicum var. genovese and Ocimum. basilicum var. minimum originating from Serbia for further industrial production of antimicrobial- and/or antioxidant-valued products. The results of this study confirm that essential oils of O. basilicum var. genovese and var. minimum represent a significant source of bioactive compounds, especially linalool, with a high rate of biological activities. Similar behaviour is observed for hydrolates, which are the by-product of the essential oil distillation process and can be utilised as bioactive-rich waste in further investigation
Artificial Neural Network as a Tool for Estimation of the Higher Heating Value of Miscanthus Based on Ultimate Analysis
No full textMiscanthus is a perennial energy crop that produces high yields and has the potential to be converted into energy. The ultimate analysis determines the composition of the biomass and the energy value in terms of the higher heating value (HHV), which is the most important parameter in determining the quality of the fuel. In this study, an artificial neural network (ANN) model based on the principle of supervised learning was developed to predict the HHV of miscanthus biomass. The developed ANN model was compared with the models of predictive regression models (suggested from the literature) and the accuracy of the developed model was determined by the coefficient of determination. The paper presents data from 192 miscanthus biomass samples based on ultimate analysis and HHV. The developed model showed good properties and the possibility of prediction with high accuracy (R-2 = 0.77). The paper proves the possibility of using ANN models in practical application in determining fuel properties of biomass energy crops and greater accuracy in predicting HHV than the regression models offered in the literature
Chemical profile of nepeta cataria l. Var. Citriodora (becker) essential oil and in vitro evaluation of biological activities
No full textEssential oil (EO) obtained by hydrodistillation in a Clevenger-type apparatus from aerial parts of Nepeta cataria L. var. citriodora (Becker), cultivated in Serbia was subjected to gas chromatography-mass spectroscopy (GC-MS) to determine the composition. Furthermore, N. cataria var. citriodora essential oil was tested to determine its antimicrobial, antioxidant, antihyperglycemic and anti-inflammatory activities in vitro. The antimicrobial activity was tested by broth microdilution method against 16 bacterial strains from American Type Culture Collection (ATCC). Four common tests for measuring in vitro antioxidant activity were used: 2, 2-diphenyl-1-picrylhydrazyl assay (DPPH), reducing power (RP), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and beta-carotene bleaching assay (BCB). Antihyperglycemic activity was examined by using alpha-glucosidase inhibitory potential (AHgA), while anti-inflammatory activity (AIA) was determined by protein denaturation bioassay, using egg albumin. In total, 36 compounds were isolated and detected by GC-MS technique in N. cataria var. citriodora EO. The EO is mainly comprised of oxygenated monoterpenes (93.1%), and the main compounds were two monoterpenoid alcohols, nerol (38.5%) and geraniol (24.9%), followed by two aliphatic aldehyde, geranial (14.6%) and neral (11.0%). Antimicrobial activity of this EO shows growth inhibition of all tested bacteria strains, and exhibited good antioxidant, antihyperglycemic and anti-inflammatory activities. The EO obtained from N. cataria var. citriodora grown in Serbia shows valuable biological activity, indicating its potential for use as a supplement in everyday diet and as a natural preservative in food industry