Selenium biofortification

Selen (Se) je mikronutrijent koji se u prirodi pojavljuje u tragovima, ali u brojnim organskim i anorganskim oblicima. Primijenjen u odgovarajućim koncentracijama ima brojne pozitivne učinke na organizme, dok izloženost prekomjernim koncentracijama Se vodi ka toksičnosti i oksidacijskom stresu. Količina Se koja se dnevno unosi prehranom odraz je zastupljenosti elementa u tlu. Na svjetskoj razini prevladavajući je udio područja siromašnih Se, stoga se pojavljuje i velik broj oboljelih od malnutricije. Obećavajuće rješenje problema je biofortifikacija usjeva, ponajprije pšenice, jedne od najzastupljnijih žitarica u prehrani ljudi. Biofortifikacija usjeva poboljšava kvalitetu prehrambenih proizvoda uslijed povećanja koncentracije bioraspoloživog Se, a na područjima siromašnim Se najčešći izbor je agronomska biofortifikacija.Selenium (Se) is a micronutrient that occurs in trace amounts but numerous organic and inorganic forms. Applied in appropriate concentrations, it has numerous positive effects on the living organisms, while exposure to excessive concentrations of Se leads to toxicity and oxidative stress. The amount of Se that is ingested daily through food reflects the presence of the element in soil. Globally, the share of low Se areas is predominant, and consequently, many malnutrition patients also occur. A promising solution to the problem is the biofortification of crops, primarily wheat, one of the main cereals in human nutrition. Crop biofortification improves the quality of food products due to the increase in the concentration of bioavailable Se, and in low Se areas, the most common choice is agronomic biofortification

Fitokemijski sastav mljevene začinske paprike iz istočne Dunavske regije

This study aimed to evaluate the phytochemical composition of sweet and hot ground paprika originating from different production sites in the Eastern Danube Region, i.e. in Croatia, Serbia and Hungary. Obtained results showed that composition and level of metabolites as well as antioxidant activity in paprika samples varied greatly among different locations. For the first time, clear differences in the chemical composition of sweet and hot paprika obtained from two Hungarian wax pepper cultivars produced in three different states of the Eastern Danube region were determined. Averagely, paprika samples from Croatia had the highest carotenoid content but the lowest levels of phenols and flavonoids. The hot paprika samples from Croatia had the highest content of capsaicin and dihydrocapsaicin. Thus, the results of this investigation indicate that bioactive compounds in paprika can vary greatly depending on their geographical origin. However, this variation can also occur due to different production technology and processing methods. Further investigations and methods need to be employed to determine the factors responsible for variation of content of bioactive compounds in paprika.Cilj ovog istraživanja bio je utvrditi fitokemijski sastav slatke i ljute začinske paprike podrijetlom iz različitih uzgojnih područja u Istočnoj dunavskoj regiji, tj. u Hrvatskoj, Srbiji i Mađarskoj. Dobiveni rezultati pokazali su kako se sastav i razina metabolita, kao i antioksidacijska aktivnost, u uzorcima začinske paprike značajno razlikuju između različitih uzgojnih područja. Prvi su put istaknute jasne razlike u kemijskome sastavu slatkih i ljutih sorata mađarske paprike proizvedene u tri različite države Istočne dunavske regije. Općenito, uzorci paprike iz Hrvatske imali su najveći sadržaj karotenoida, ali najniže vrijednosti fenola i flavonoida. Uzorci ljute paprike iz Hrvatske imali su najveći sadržaj kapsaicina i dihidrokapsaicina, kao i najviše Scovilleovih jedinica ljutine. Stoga, ovo istraživanje ukazuje na prikladnost određenih uzgojnih područja za dobivanje paprike željenoga kemijskoga sastava. Podatci su vrlo zanimljivi i važni za prehrambeno prerađivačku i farmaceutsku industriju, kao i za usmjeravanje regionalnih proizvođača prema dobivanju kvalitetne mljevene paprike

Does plant growing condition affects biodistribution and biological effects of silver nanoparticles?

Among the many different types, silver nanoparticles (AgNPs) are the most commercialized and applied engineered nanoparticles in a wide range of areas, including agriculture. Despite numerous studies on their safety and toxicity of AgNPs, data on their effect and interactions with terrestrial plants are largely unknown. This study aimed to investigate the effect of growing conditions on the response of pepper plants (Capsicum annuum L.) to citrate-coated AgNPs. Growth parameters, biodistribution, and defence response were examined in peppers grown hydroponically or in soil substrate. In addition, the effects of nano and ionic form of silver were compared. The leaves and stems of peppers grown in substrate showed a higher bioaccumulation compared to hydroponically cultivated plants. The nano form of silver accumulated to a higher extent than ionic form in both leaves and stems. Both silver forms inhibited pepper growth to a very similar extent either through hydroponic or substrate growing settings. Unlike other studies, which investigated the effects of unrealistically high doses of AgNPs on different plant species, this study revealed that vascular plants are also susceptible to very low doses of AgNPs. Both silver forms affected all parameters used to evaluate oxidative stress response in pepper leaves ; plant pigment and total phenolics contents were decreased, while lipid peroxidation and hydrogen peroxide level were increased in treated plants. Similar biological effects of both nano and ionic Ag forms were observed for both substrate and hydroponic growing systems

Wheat Leaf Antioxidative Status—Variety-Specific Mechanisms of Zinc Tolerance during Biofortification

In this study, we evaluated the leaf antioxidative responses of three wheat varieties (Srpanjka, Divana, and Simonida) treated with two different forms of zinc (Zn), Zn-sulfate and Zn-EDTA, in concentrations commonly used in agronomic biofortification. Zn concentration was significantly higher in the flag leaves of all three wheat varieties treated with Zn-EDTA compared to control and leaves treated with Zn-sulfate. Both forms of Zn increased malondialdehyde level and total phenolics content in varieties Srpanjka and Divana. Total glutathione content was not affected after the Zn treatment. Zn-sulfate increased the activities of glutathione reductase (GR) and guaiacol peroxidase (GPOD) in both Srpanjka and Divana, while glutathione S-transferase (GST) was only induced in var. Srpanjka. Chelate form of Zn increased the activities of GST and GPOD in both Simonida and Divana. Catalase activity was shown to be less sensitive to Zn treatment and was only induced in var. Srpanjka treated with Zn-EDTA where GPOD activity was not induced. Concentrations of Zn used for agronomic biofortification can induce oxidative stress in wheat leaves. The antioxidative status of wheat leaves could be a good indicator of Zn tolerance, whereas wheat genotype and chemical form of Zn are the most critical factors influencing Zn toxicity

Vermicomposting—Facts, Benefits and Knowledge Gaps

Industrialization and urbanization have led to an increased accumulation of waste materials that are transformed into a nutrient-rich and high-quality product called vermicompost by the vermicomposting process. Vermicomposting is an ecofriendly and economically favorable biotechnological process that involves the interaction of earthworms and microorganisms. Due to the importance of this process and its great potential in dealing with the consequences of waste accumulation, this review aims to provide key insights as well as highlight knowledge gaps. It is emphasized that there is a great challenge in understanding and clarifying the mechanisms involved in the vermicomposting process. The optimization of the factors affecting the possible application of vermicompost is crucial for obtaining the final product. Information on the composition of bacterial communities, amount of vermicompost, effect on heavy metal content, plant pathogens, diseases and organic waste selection is here recognized as currently the most important issues to be addressed. By answering these knowledge gaps, it is possible to enable wider utilization of vermicompost products

Does plant growing condition affects biodistribution and biological effects of silver nanoparticles?

Among the many different types, silver nanoparticles (AgNPs) are the most commercialized and applied engineered nanoparticles in a wide range of areas, including agriculture. Despite numerous studies on their safety and toxicity of AgNPs, data on their effect and interactions with terrestrial plants are largely unknown. This study aimed to investigate the effect of growing conditions on the response of pepper plants (Capsicum annuum L.) to citrate-coated AgNPs. Growth parameters, biodistribution, and defence response were examined in peppers grown hydroponically or in soil substrate. In addition, the effects of nano and ionic form of silver were compared. The leaves and stems of peppers grown in substrate showed a higher bioaccumulation compared to hydroponically cultivated plants. The nano form of silver accumulated to a higher extent than ionic form in both leaves and stems. Both silver forms inhibited pepper growth to a very similar extent either through hydroponic or substrate growing settings. Unlike other studies, which investigated the effects of unrealistically high doses of AgNPs on different plant species, this study revealed that vascular plants are also susceptible to very low doses of AgNPs. Both silver forms affected all parameters used to evaluate oxidative stress response in pepper leaves; plant pigment and total phenolics contents were decreased, while lipid peroxidation and hydrogen peroxide lever were increased in treated plants. Similar biological effects of both nano and ionic Ag forms were observed for both substrate and hydroponic growing systems

Defense Response to <i>Fusarium</i> Infection in Winter Wheat Varieties, Varying in FHB Susceptibility, Grown under Different Nitrogen Levels

Fusarium head blight and inadequate nitrogen fertilization can cause numerous biochemical changes in wheat. The main aim of this study was to determine the effects of Fusarium inoculation and a broader range of different nitrogen fertilization on the defense response in the spikes of four wheat varieties, varying in FHB susceptibility. Total soluble phenolics content, activities of enzymes involved in phenol metabolism (PAL and PPO), and total antioxidant capacity were determined as indicators of defense response. In both growing seasons, Fusarium inoculation altered PHE content in wheat spikes, indicating involvement of PHE in the defense response to Fusarium attack. Increased PHE content in the partially resistant varieties (Apache and Graindor) indicates involvement of PHE in the defense response and better disease tolerance in the more resistant varieties. Breeding wheat varieties with enhanced PHE synthesis could be a promising strategy to control FHB. To the best of our knowledge, this is the first study that emphasizes the effects of Fusarium infection and a broader range of different nitrogen fertilization on PHE and enzymes involved in PHE metabolism. In addition, this is the first study using the FRAP method to determine the antioxidant capacity of wheat tissues under the influence of Fusarium infection and different nitrogen fertilization

Utjecaj gnojidbe dušikom i inokulacije vrstom Fusarium culmorum na biomarkere oksidacijskoga stresa listova zastavičara pšenice

During cultivation, wheat is exposed to several abiotic and/or biotic stress conditions that may adversely impact the wheat yield and quality. The impact of abiotic stress caused by nitrogen deficiency and biotic stress caused by phytopathogenic fungus Fusarium culmorum on biomarkers of oxidative stress in the flag leaf of nine winter wheat varieties (Ficko, U-1, Galloper, BC Mandica, BC Opsesija, Ingenio, Isengrain, Felix, and Bezostaya-1) was analyzed in this study. Hydrogen peroxide concentration and lipid peroxidation level were measured as indicators of oxidative stress, while the antioxidant response was determined by measuring the concentration of phenolic compounds and activities of antioxidant enzymes. Wheat variety and nitrogen treatment had a significant effect on all examined biomarkers of oxidative stress in the flag leaf, while the impact of Fusarium treatment was less pronounced. The most significant impact on the measured stress biomarkers had a low nitrogen level, which mainly increased hydrogen peroxide concentration and lipid peroxidation level and decreased activities of antioxidant enzymes in most varieties. The obtained results were discussed and compared with the previous study in which biochemical analyzes were performed on the wheat spike. There was no significant strong correlation between flag leaf and spike response in the measured parameters, which, in addition to the variety-specific response, also indicates a tissue-specific antioxidant response.Pri uzgoju je pšenica izložena brojnim abiotičkim i/ili biotičkim stresnim čimbenicima koji mogu negativno djelovati na prinos i kvalitetu. U ovome je radu analiziran utjecaj abiotičkoga stresa uzrokovanog deficitom dušika i biotičkoga stresa izazvanog fitopatogenom gljivom Fusarium culmorum na biomarkere oksidacijskoga stresa u listu zastavičaru devet sorata ozime pšenice (Ficko, U-1, Galloper, BC Mandica, BC Opsesija, Ingenio, Isengrain, Felix i Bezostaya-1). Kao pokazatelji oksidacijskoga stresa mjereni su koncentracija vodikova peroksida i razina lipidne peroksidacije, dok je antioksidacijski odgovor određen mjerenjem koncentracije fenolnih spojeva i aktivnosti antioksidacijskih enzima. Sorta pšenice i tretman dušikom imali su značajan utjecaj na sve ispitivane biomarkere oksidacijskoga stresa u listu zastavičaru, dok je utjecaj tretmana gljivom Fusarium bio manje izražen. Najznačajniji utjecaj na mjerene pokazatelje stresa imao je uzgoj u uvjetima niske razine dušika, pri čemu je u većini sorata vidljiv trend povećanja koncentracije vodikova peroksida i razine lipidne peroksidacije te smanjenja aktivnosti antioksidacijskih enzima. Dobiveni su rezultati prokomentirani i uspoređeni s prijašnjim rezultatima biokemijskih analiza provedenih na klasu pšenice. Značajno jake korelacije između lista zastavičara i klasa u mjerenim parametrima nije bilo, što uz sortno-specifični odgovor upućuje i na tkivno-specifičan antioksidacijski odgovor