The study was conducted to investigate the effects of sodium selenate foliar application on the biofortification of selenium (Se) compositions of grain maize (Zea mays L. cvs. DKC 5783 F₁). The experiment was carried out in a randomized block design with three replications, and sodium selenate (Na₂SeO₄) was applied at eight different levels (0, 5, 10, 15, 25, 50, 75, 100 g Se ha⁻¹) from the foliar when the maize plant reached 50–70 cm in height. Applications did not statistically affect yields and biomass, the contents of total nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), iron (Fe), copper (Cu), manganese (Mn), zinc (Zn), boron (B), and molybdenum (Mo), but it affected Se content. The total Se levels varied between 27 and 523 µg kg⁻¹, the highest value was obtained from 100 g Se ha⁻¹ application. When the amount of foliar-applied Se was increased from 0 to 100 g Se ha⁻¹, the Se content increased by 19.37-fold and Se accumulation increased by 19.30-fold. Se recovery showed no significant change across the Se rates with an average of 37.01%. Foliar selenium application showed a significantly greater potential for increasing the Se level in grain maize, with 1 g of Se ha⁻¹ increasing the grains by 5.23 µg kg⁻¹. In this study, the Se content of maize grain increased with foliar selenate application. For human Se nutrient, it would be necessary to consume more than 100 g of maize (dry weight) per day with the foliar selenate application to maize.

Background: Olive stone (OS) has emerged as a promising by-product with potential applications in food and feed formulations, owing to its unique properties. Despite growing interest in recent years, research dedicated to the comprehensive evaluation of OS remains limited. Aim: This review aimed to elucidate the structure, physical and chemical properties of OS, provide an overview of its diverse application areas, and highlight its potential utilization in food and feed formulations through case studies and recent advancements. Methods: A systematic literature search was conducted using prominent databases, including Google Scholar, Web of Science, PubMed and Scopus, with a focus on studies published in recent years. The search strategy employed keywords such as olive, olive by-products, olive stone composition, valorization areas, use of agricultural wastes in food. Relevant publications in English or Turkish were considered, resulting in a reference list of 97 articles that were critically reviewed and cited. Results: OSs are a significant by-product generated during the olive oil extraction and pitted table olive production, constituting approximately 18-22% of the olive fruit. OS possesses a lignocellulosic composed primarily of hemicellulose, cellulose and lignin. Although its current predominant use is as fuel due to its high calorific value, OS exhibits potential for diverse applications owing to its rich composition of fat, protein, bioactive phenolic compounds and dietary fiber. Potential valorization pathways include activated carbon production, oil extraction, furfural synthesis, plastic filling material, cosmetic formulations, biosorbents, resin production, and animal nutritional supplementation. Recent studies have increasingly explored the use of OSs as a functional food ingredient, with promising results demonstrating its efficacy as an antioxidant, nutraceutical and thickening agent in food formulations. Conclusion: This review underscores the multifaceted potential of OS, particularly in food and feed applications. The valorization of OS aligns with sustainable waste management practices and offers innovative opportunities for enhancing food and feed formulations. Keywords: Olive, olive stone, waste management, waste valorization, agricultural by-product.

This study was conducted to determine the nutritional status of olive cultivated land and olive plant in Izmir and Mugla province in terms of boron and other elements. For this purpose, 254 soil samples (0-30 cm depth) and 254 leaf samples were taken simultaneously with GPS coordinates from the olive production areas and analyzed (125 gardens in Datca, Koycegiz, Milas, Ula, Seydikemer districts of Mugla province / 129 gardens in Aliaga, Bayindir, Bergama, Dikili, Foca, Karaburun, Kemalpasa, Menderes, Menemen, Odemiş, Seferihisar, Selcuk, Tire, Torbali and Urla district of Izmir province). In the soil samples texture, pH, EC, lime, organic matter, extractable boron, iron, copper, zinc and manganese analysis were done. In the leaf samples total boron, iron, copper, zinc and manganese content were determined. According to the analysis results, the nutritional studies of olive were determined in term of boron and other elements. According to the results of the research, boron contents of the research areas soils ranged between 0.20 and 5.24 mg kg-1 and the average level was determined as 1.21 mg kg-1. In the boron content distribution of the soils in the research area 13.78% is low, 76.38% is sufficient, 9.45% is more and 0.39% is too high. Boron contents of olive leaves ranged between 8.66 and 29.33 mg kg-1 and the average level was determined as 8.66 mg kg-1. In the boron content distribution of the leaves in the research area 85.04% is low, 14.96% is sufficient. Based on the B contents of all soil and leaf samples it was interesting to note that although 85.83% of the soils have sufficient boron, 85.04% of the leaves show boron deficiency, indicating that boron nutritional problems are experienced. Also according to the results of analysis, it was determined that there were no nutritional problems in terms of iron, and that there were serious nutritional problems in terms of boron and zinc. It was determined that nutritional problems in term of manganese and copper slightly. As with all plant species, fertilization programs for olive plant should be established according to soil and leaf analysis result. According to the results of analysis, it is important to give the deficient macro and micronutrients in addition to phosphorus, nitrogen and potassium fertilizers which will be given with basic fertilization.

This study was conducted to determine the effect of boron (B) applications on the olive yield and quality in Izmir and Mugla province of Turkey. For this purpose, 254 soil and leaf samples were taken simultaneously and analyzed. After the analysis six locations with different B levels were chosen. The soil-leaf content was 0.83–12.03 mg kg⁻¹ in Milas, 0.85–14.39 mg kg⁻¹ in Seydikemer; 0.36–16.99 mg kg⁻¹ in Dikili; 0.23–16.80 mg kg⁻¹ in Odemis; 0.65–16.69 mg kg⁻¹ in Urla and 1.40–17.29 mg kg⁻¹ in Bergama, respectively. The field trials were carried out in five replicates according to the random blocks, four application types (control (C), soil (S), foliar (F), soil + foliar (S + F)). S applications (0 g B tree⁻¹; 4000 g B ha⁻¹) were done before the shoot activity, F application (0 mg B L⁻¹; 300 mg B L⁻¹) was done after harvest, before flowering, after fruit set. The F application increased yield 47% at Bergama and 75% at Odemis location. In other locations, applications are not effective statistically, but when compared with the C group, the yield values increase with F and S + F applications. It is thought that this increase of yield is very important for olive plants and it was related to the B contents of the leaves and fruits. B applications increased B content of leaves and fruits, and affected the dry matter and oil content of fruits. The results suggest that foliar B applications are effective in increasing olive yield, and application should be done at three different times after harvest, before flowering and after fruit set. Further studies on B should take the cultivar into account for a faster progress in the knowledge on B mobility in olive.

In this study, newly formulated gluten-free chips with almond powder were produced. Almond powders were obtained using 3 different drying methods: oven drying, freeze drying, and microwave drying. This study aimed to determine the effect of drying almond powders used in gluten-free chip production using different drying methods and then adding different ratios (10% and 30%) of these powders to the chips on the physicochemical, textural, mineral, and sensory properties of the chips. The physical, textural, mineral, and sensory analyses were then carried out. The moisture content values of the chips with almond powder were < 6.32% and the water activity values were < 0.300. Adding almond powder increased the total fat and protein content of the chip samples. The protein content of the gluten-free chips increased by 34.69-257.14% compared to the control sample and the highest protein content (1.75%) was determined in the samples containing 30% of the almond powder obtained using the microwave drying method. The hardness of the gluten-free chips decreased by increasing the almond powder. The addition of the almond powder to the chip formulation generally increased the B, Cu, Mn, and Zn contents of the gluten-free chips. All chip samples enriched with almond powder showed similar overall acceptability scores (5.00-6.89).

Soil organic carbon (SOC) and total nitrogen (TN) have a very important role in sustainable soil quality, crop production, and environmental impacts, and determining of carbon nitrogen ratio (C: N ratio) is very important for creating data banks in terms of ecosystem functions. Plants influence the interaction of SOC and TN, as well as ecosystem yield and the continental carbon cycle. Climate, atmosphere, and land-use change are all included in numerical models of the carbon (C) and nitrogen (N) cycles. This study was conducted to determine the SOC and TN stocks, the C: N ratio and their relationships with the soil properties of olive orchards in Aliaga, Bayindir, Bergama, Dikili, Foca, Karaburun, Kemalpasa, Menderes, Menemen, Odemis, Seferihisar, Selcuk, Tire, Torbali and Urla provinces of Izmir in Turkey. For this purpose, 129 soil samples were taken from 0-30 cm depth. The texture, pH, EC, lime, OM, SOC and TN content and stocks, Bulk density (Db) was determined. Db and C: N ratio varied between 0.84-1.31 g cm-3, 5.17-80.50, and SOC density and stocks changed between 4.00-53.00 mg cm-3, 1.25-1.59 kg m-2, N density and stocks between 0.09-2.66 mg cm-3, 0.03-0.80 kg m-2, respectively. The highest BD was obtained from Tire, the highest SOC stocks from Karaburun, the highest TN from Seferihisar and Karaburun. The very small bulk density which is negatively associated with OM and clay is an important feature. The SOC contents were higher in relatively heavy rainfall regions. SOC and soil texture have a strong relationship. As a result, texture, precipitation, temperature, soil depths, and regeneration of soil affect the SOC and TN stocks. The results may be effective in terms of sustainable soil quality and ecosystem functions for olive cultivation.