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Identification of the trace and toxic elements of wheat cultivated in different regions of Uzbekistan
2024
Djaxangirova, Gulnoza | Kurbanova, Nodira | Kurbanov, Bakhtiyor
In Uzbekistan, the main food product is bread, which is produced in various forms from local and imported wheat. Most of it is not studied by microelement analysis. The objective of this study is to quantify trace elements in locally produced wheat from various cultivated regions of Uzbekistan. Four different varieties of wheat are cultivated in Sirdarya, Tashkent region, Kashkadarya and Fergana were selected for analysis. Next, a comparative analysis of the elemental composition like iron, zinc, potassium, calcium etc., in the selected samples were studied. To carry out the above aims, an innovative research method was chosen, which is called improved instrumental neutron activation analysis. This method differs from others in its high accuracy in determining trace elements and its multi-element nature. Using this method, we can understand how insufficient nutrients are in baked goods made from wheat grain grown in Uzbekistan. Based on the results of the study, it can be recommended to enrich the soil with fertilizers high in iron and zinc. As a result, in turn, will have a positive effect on the health of the population, since today there is a shortage of the above listed elements. It was also revealed that the concentration of potassium and calcium in wheat cultivated in Uzbekistan is in a high state than other elements. Using the chosen method, two toxic elements were determined and according to the analysis for toxic elements, all four samples are recommended for consumption, as they do not exceed the permissible level for food safety.
Показать больше [+] Меньше [-]Evaluating early changes in young tree seedlings under simulated urban environment
2024
Černiauskas, Valentinas | Varnagirytė-Kabašinskienė, Iveta
Urban trees, integral to urban environments, demonstrate intricate responses to atmospheric pollutants like particulate matter (PM), tropospheric ozone (O₃), and carbon dioxide (CO₂). Notably, O₃ induces oxidative stress in leaf tissues, while PM, consisting of fine airborne particles, interacts with urban trees through foliar deposition. This interaction is particularly interesting as tree canopies are highly effective filters, capturing and accumulating PM on their surfaces. The present study focused on silver birch, small-leaved lime, and Norway maple seedlings responses to elevated O₃ and CO₂). With and without PM. Maple seedlings exhibited the highest stem height increment, followed by lime and birch. Elevated O₃ and CO₂ without PM led to substantial height increments for lime and maple. Elevated O₃ and CO₂ without PM increased the total polyphenols in lime and maple leaves but decreased the content of total flavonoids in birch and lime leaves. Our findings underscore the adaptability of lime and maple seedlings to elevated O₃ and CO₂, positioning them as promising species for urban environments in the face of changing climates. Birch, while exhibiting biochemical changes, demonstrated less pronounced growth responses. This studyʼs insights into the intricate interactions between urban trees and multiple pollutants, particularly the species-specific responses, are of significant value for urban planning and environmental management.
Показать больше [+] Меньше [-]Rosemary essential oil by hydrodistillation: SPME-GC-MS characterization
2024
Calvo-Gomez, Octavio | Ruzibayev, Akbarali | Akramova, Rano | Salijonova, Shakhnozakhon | Gaipova, Shakhnozakhon | Khodjaev, Sarvar
Rosemary (Salvia rosmarinus) is an aromatic herb with a multitude of uses. It is both a seasoning in various dishes, and a natural remedy for several diseases mainly due to its anti-inflammatory and anti-oxidative effects. Plus, it is also used in cosmetic industry and for improving agriculture practices and helping the environment, since it may be a natural antimicrobial. It is worth noting that this plant is also grown and commercialized in Uzbekistan, thus, if added value is given to rosemary’s products, it has potential for improving living conditions and helping in the economy of local farmers and entrepreneurs. In this work, we discuss a technique for obtaining rosemary essential oil, rich in terpenes, by vacuum assisted hydrodistillation. This is a solventless environmentally friendly and safe technique that allows the obtention of an added value rosemary product where terpenes, compounds responsible for most of rosemary’s properties, are the most abundant. Two samples of locally acquired rosemary were sourced, essential oil was extracted, and characterization was then performed by Solid Phase Micro Extraction (SPME) and Gas Chromatography – Mass Spectrometry (GC-MS). As a comparison, a direct injection of a dilution of one of the essential oil samples was also performed. It was concluded that samples of essential oil obtained from both sources were entirely composed of terpenes or terpene derivatives. Besides, SPME was a superior method when compared to direct injection, since a larger number of volatiles was able to be identified.
Показать больше [+] Меньше [-]Chemometrics as an aid to quickly evaluate galactomannans through infrared spectroscopy
2024
Calvo-Gomez, Octavio | Ruzibayev, Akbarali | Salijonova, Shakhnozakhon | Gaipova, Shakhnozakhon | Khodjaev, Sarvar | Khakimova, Zulfiyakhon | Rakhimov, Dilshod
Galactomannans, composed of galactose and mannose, may form gels and are considered safe because of their non-toxic, biodegradable, and biocompatible nature. As a result, they are widely utilized in the food industry as stabilizers and thickeners. Among galactomannan producing species, guar gum and locust bean gum are particularly important due to their economical relevance. Guar gum and locust bean gum are often adulterated with cellulose gums like xanthan gum and carboxymethyl cellulose (CMC). Adulteration of galactomannans with other gums may introduce uncertainties regarding functionality and complicate quality control, posing a potential problem for the food industry. Among the different techniques which have been used for determining and characterizing galactomannans, Fourier Transform Infrared Spectroscopy stands out. Especially when coupled to Attenuated Total Reflection (ATR), analyses are performed rapidly, with a minimum sample preparation, and without the need for solvent or previous extraction mechanisms. However, food is a very complex matrix that contains a high number of components which generate a multitude of spectral information and large data sets. Consequently, additional data processing tools such as chemometrics are needed to be able to draw useful information from spectra. Our goal in this work is to show how to optimize conditions for instrumental analysis by infrared spectroscopy of galactomannans and its constituent monomers and create a chemometric model where galactomannans could be differentiated as a single group. We successfully optimized the PCA model obtained after chemometric processing of infrared data through reducing dimensions by loadings selection.
Показать больше [+] Меньше [-]Long term effects of total biomass harvesting on understory vegetation and tree stand in Norway spruce stands
2023
Čakšs, Roberts | Jansone, Baiba
Northern Europe will be one of the locations where the renewable energy from forests could displace fossil fuels as a result of climate change: therefore, it will become more crucial to maintain renewable materials that also collect CO2. By taking tree biomass out of forest stands, we could create more renewable resources to use in practice, but this has certain negative effects on the forest ecology, including nitrogen leaching and vegetation degradation. The goal of the study is to investigate the effects of full biomass removal (FBR) in Norway spruce (Picea abies (L.) H. Karst.) forest stands and how this forest management affects vegetation regeneration, tree stock and carbon storage overall. The aforementioned structures were assessed at various forest ages. The central region of Latvia contains Norway spruce stands with all of the sample sites under study situated on drained peaty mineral soils and weakly aerated gleyic soils. As a result of the long-term evaluation, it was determined that the forest vegetation in FBR was similar to that in the same-age control stand (SAC) and that vegetation can successfully regenerate. The average tree height and DBH is lower in areas where stump removal and understory biomass was not carried out. Statistically significant (p<0.05) long-term influence of stump removal on the average height and diameter of Norway spruce can be identified in all parameters, except, tree height in Myrtillosa mel. forest type. Total biomass removal in long term has almost no significant effect on tree stand and vegetation regeneration.
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