Micronutrient Content Research Articles

Salinity Tolerance Mechanism of Crithmum maritimum L.: Implications for Sustainable Agriculture in Saline Soils

Edible halophytes are attracting attention due to their potential for agriculture in saline and marginal areas. The salt tolerance mechanism was analyzed in Crithmum maritimum L., based on ionic, osmotic, and redox homeostasis strategies under salt stress. The methodology involved growing C. maritimum seeds in pots under controlled greenhouse conditions and exposing them to different NaCl concentrations (0, 100, 200, and 300 mM) for five months. High salinity levels decreased plant length and biomass, but the shoot-to-root length and biomass ratio increased significantly. Photosynthetic pigments (chlorophyll and carotenoids) were quantified using spectrophotometric analysis, while macro- and micro-nutrient contents were determined via the Kjeldahl method, flame photometry, and atomic absorption spectrophotometry. Osmolyte accumulation, including proline and glycine betaine, was analyzed using specific biochemical assays, and antioxidant enzyme activities (SOD, CAT, and POX) were measured to assess redox homeostasis. Photosynthetic pigments in C. maritimum leaves slightly increased at 100 mM NaCl, but significantly declined at 200 and 300 mM NaCl. A high Na content in the shoots indicated no restriction in mineral uptake in the roots. Nitrogen and phosphorus slightly decreased under high salinity. The cation content in the shoots varied: potassium decreased, while calcium and magnesium increased with salinity, although the Mg+2/Na+ and K+/Na+ ratios showed similar declining patterns. The micro-nutrients iron and manganese increased in the shoots, while copper remained unchanged. The content of osmolytes proline and glycine betaine significantly increased under the 200 and 300 mM NaCl treatments. Antioxidant enzyme activities (SOD, CAT, and POX) decreased at 100 and 200 mM NaCl, but were strongly induced at 300 mM NaCl. The total antiradical activity of the leaves increased with higher salinity levels. Our results indicated that the facultative halophyte characteristics of C. maritimum emerged after exposure to 200 mM NaCl. Increased calcium content may be a key factor in salinity tolerance. We concluded that C. maritimum employs strong osmotic adjustment and redox homeostasis mechanisms, making it a promising candidate for cultivation in saline environments.

Dried Anaerobic Digestate from Slaughterhouse By-products: Emerging Cues for a Bio-Based Fertilization

AbstractThe slaughterhouse and meat industry are worldwide rapidly growing and produce billions of tonnes of organic wastes annually. These materials can be used to produce biogas through anaerobic digestion and the resulting digestate represents a potential source of organic carbon and nutrients that could be applied to the soil as organic fertilizer. The present work aims to assess the fertilizing potential of a dried anaerobic digestate (DD) produced from beef slaughtering waste. DD was characterized at the physic-chemical level, particularly focusing on macro- and micronutrient contents, potentially toxic element and organic contaminants. Then, a short-term soil incubation experiment was performed on two different soils. After the incubation, DD released 10–26% of their total nitrogen (N) and 13–16% of total phosphorus (P), depending on the soils that had different characteristics and responded differently to the treatments. However, DD had positive effects on the principal soil fertility indicators, such as chitinase and phosphatases, stimulating the microbial activity and therefore exploiting a fertilizing potential as well as the other organic fertilizers tested. Moreover, DD had minor effects on soil extractable carbon (Cext) suggesting the presence of recalcitrant C forms in spite of soluble C, indicating a higher stability of slaughterhouse by-products after anaerobic digestion in respect to the other organic fertilizers. The results obtained in this work raise the concrete possibility use DD as a bio-based fertilizer. Graphical Abstract

Managing nutrition-biodiversity trade-offs on coral reefs

Coral reefs support an incredible abundance and diversity of fish species, with reef-associated fisheries providing important sources of income, food, and dietary micronutrients to millions of people across the tropics. However, the rapid degradation of the world's coral reefs and the decline in their biodiversity may limit their capacity to supply nutritious and affordable seafood while meeting conservation goals for sustainability. Here, we conduct a global-scale analysis of how the nutritional quality of reef fish assemblages (nutritional contribution to the recommended daily intake of calcium, iron, and zinc contained in an average 100g fish on the reef) relates to key environmental, socioeconomic, and ecological conditions, including two key metrics of fish biodiversity. Our global analysis of more than 1,600 tropical reefs reveals that fish trophic composition is a more important driver of micronutrient concentrations than socioeconomic and environmental conditions. Specifically, micronutrient density increases as the relative biomass of herbivores and detritivores increases at lower overall biomass or under high human pressure. This suggests that the provision of essential micronutrients can be maintained or even increase where fish biomass decreases, reinforcing the need for policies that ensure sustainable fishing, and that these micronutrients are retained locally for nutrition. Furthermore, we found a negative association between micronutrient density and two metrics of fish biodiversity, revealing an important nutrition-biodiversity trade-off. Protecting reefs with high levels of biodiversity maintains key ecosystem functions, whereas sustainable fisheries management in locations with high micronutrient density could sustain the essential supply of micronutrients to coastal human communities.

Micronutrient and heavy metal bioaccumulation in Bermuda grass (Cynodon dactylon L. Pers) grown in calcareous soil using stabilized and dried sewage sludge

This study examines the micronutrients and heavy metal bioaccumulation in Bermuda grass (Cynodon dactylon L. Pers), grown in two different types of calcareous soil (CS) with the application of stabilized and dried sewage sludge (SS). At the end of the growth period, the Fe, Zn, Mn and Cu (micronutrients) concentrations in the substrate have increased. Furthermore, it was determined that the total Fe, Zn, Mn and Cu concentrations were higher in CS1 compared to CS2. For the heavy metals the concentrations of Ni and Cr have increased, and the concentration of total Cd has slightly but significantly decreased. The total Pb concentration was below the detection limit (DL for Pb <0.03 mg kg-1). It was determined that the total Ni, Cr and Cd concentrations were higher in CS1 than in CS2. In the aerial biomass of the Bermuda grass, the Fe and Zn concentrations have increased with increasing SS applications, whereas Mn concentrations have decreased. Ni, Cr, Cd and Pb concentrations were unaffected by SS applications for both types of CS. The bioconcentration factor (BCF) values for the shoot of the plant (BCFFe, BCFZn, BCFMn, BCFCu, BCFNi, BCFCr, BCFCd) were determined to be below the critical limit of 1. The application of sewage sludge has not resulted in bioaccumulation above critical limits in the shoot of the plant. However, considering Bermuda grass substrate, it can be suggested to add sewage sludge to the calcareous soil in amounts between 20–40 t ha-1, considering its long-term remanence.

Crop rotation diversity and tillage effects on soil and wheat grain nutrient concentration in an organically-managed system

Consumer demand for high quality organic produce in Canada has in recent years contributed to the development of a more sustainable organic agriculture system that increased productivity without decreasing soil fertility. The objective of this 4-yr field study was to determine if an organic system with diversified crop rotations under reduced tillage would produce high quality spring wheat (Triticum aestivum L.) grain and improve soil fertility. A simplified rotation (SR) consisting of a forage pea (Pisum sativum L.) green manure (GM)-spring wheat sequence and a diversified rotation (DR, forage pea GM-oilseed-pulse crop-spring wheat sequence) were compared under two tillage intensities (high tillage [HT] and low tillage [LT]). The oilseed alternated between mustard (Sinapis alba L.) and flax (Linum usitatissimum L.), and the pulse alternated between field pea and lentil (Lens culinaris L.). Generally, nutrient concentrations in wheat grain were mostly significantly higher under LT than HT and in the DR compared with the SR. In addition, tillage-rotation system influenced soil zinc, calcium, magnesium, and sodium concentrations. However, grain Cd concentration was higher in the LT treatment under the DR sequence relative to other treatments. Our results indicate that organically managed diversified crop rotations under reduced tillage can produce wheat grains with high nutritional value for humans and livestock but may not increase soil micronutrient concentrations.

Biofortification in garden peas through multi-micronutrient formulations

Soil micronutrient deficiencies lead to crops with low essential element concentrations, affecting human health through micronutrient malnutrition. Effective practices, like foliar nutrient application, improve crop quality and reduce malnutrition. The garden pea (Pisum sativum L. var. hortense) is cultivated worldwide for its nutritional value and such nutrient-rich crops, through agronomic biofortification, offer a sustainable solution to global health issues by addressing micronutrient deficiencies. Four liquid micronutrient formulations [Treatment 1 (T1), Treatment 2 (T2), Treatment 3 (T3), and Treatment 4 (T4)] were prepared using either water or vermiwash as a carrier, with variations that included the presence or absence of plant growth regulators (GA3 + NAA)] and evaluated along with commercially available formulations [Arka Vegetable Special (T5) and ProKissan (T6)]. Micronutrient formulations, particularly T3, demonstrated notable effects on various parameters, including plant height, biomass, root characteristics, pod weight, and micronutrient contents in seeds of garden pea var. Kashi Nandini. T3 significantly outperformed other formulations in promoting plant growth, resulting in higher values for plant height, biomass, branches per plant, nodule mass, root biomass, surface area, volume, and density. Yield parameters such as pod length, weight, number of pods, and seeds per pod were also positively influenced by micronutrient treatments, with T3 leading to the highest overall yield, with a 24.09 % increase per plant and a 13.39 % increase per hectare compared to the control. Additionally, foliar application of micronutrients increased the concentration of copper, zinc, iron, and manganese in seeds, positively impacting seed quality. Quality parameters, including total soluble solids, protein, total phenol, and total flavonoid contents, were significantly improved by micronutrient treatments, with T3 showing the most favorable outcomes. Texture analysis indicated that peas treated with T3 had lower firmness values, suggesting maintained tenderness and sweetness. Correlation analysis revealed strong positive associations between various growth parameters, yield traits, and micronutrient contents. Overall, foliar micronutrient application proved to be a valuable biofortification strategy for enhancing the performance and quality of garden peas.

The Evaluation of Selected Trace Elements in Blood, Serum and Blood Cells of Type 2 Diabetes Patients with and without Renal Disorder.

An appropriate diet is the basis for the treatment of type 2 diabetes (T2DM). However, there are no strict recommendations regarding the content of micronutrients and their modifications in the presence of chronic kidney disease (CKD). Therefore, we decided to investigate whether T2DM patients, including those with CKD, have different levels of chromium, nickel, cobalt, magnesium, and zinc in various blood elements compared to healthy individuals. We divided our subjects into three groups: the control group (individuals without T2DM and proper renal function), those with T2DM and proper renal function, and those with T2DM and GFR < 60 mL/min/1.73 m2. We observed higher levels of chromium in all materials examined in patients with T2DM and impaired renal function. Both study groups found higher levels of nickel in samples of whole blood and red blood cells. Patients with T2DM and proper renal function had higher levels of serum manganese. Both study groups had lower levels of serum zinc. We observed higher levels of chromium in all materials examined in patients with T2DM and impaired renal function. Both study groups found higher levels of nickel in samples of whole blood and red blood cells. Patients with T2DM and proper renal function had higher levels of serum manganese. Both study groups had lower levels of serum zinc. In order to ensure effective care for patients with T2DM, it is necessary to improve the standard diet, including the content of micronutrients and their modification in patients with concomitant CKD.

Transition metals in alkaline Lost City vent fluids are sufficient for early-life metabolisms

Despite the importance of alkaline seafloor hydrothermal vents in broadening our understanding of deep-sea hydrothermal ecosystems, little is known about the mobility and concentrations of micronutrient transition metals in these environments. Here, we present new analyses of micronutrient transition metal concentrations in vent fluids from the iconic Lost City Hydrothermal Field (LCHF) and report concentrations of Fe = 2.9–18.3 µmol/kg, Zn = 1.30–5.86 µmol/kg, Cu = 0.43–5.06 µmol/kg, Ni = 86.4–556 nmol/kg, Mn = 8.3–274 nmol/kg, V = 25.9–127 nmol/kg, Mo = 24–94 nmol/kg, Co = 8.0–135 nmol/kg, W = 4.8–16 nmol/kg, and Cd = 1.7–4.5 nmol/kg. We additionally present results of a hydrothermal lherzolite alteration experiment conducted at 300 °C, 500 bar. Transition metal concentrations and major chemical parameters of experimental reaction fluids are broadly similar to LCHF vent fluids, indicating that transition metal concentrations in LCHF vent fluids, and alkaline hydrothermal fluids more generally, reflect metal solubility controlled by underlying rock-buffered hydrothermal reactions.Concentrations of Ni and Mo are especially noteworthy because of their recognized importance for biological methanogenesis (Ni) and nitrogen fixation (Mo). When compared with known biological thresholds, our findings indicate that Ni concentrations in LCHF vent fluids are sufficient to support the robust methane-metabolizing microbial communities observed in the immediate vicinity of LCHF vents and suggest that Ni availability influences the spatial distribution of LCHF methanogens. Furthermore, our laboratory hydrothermal experiments demonstrate that Mo concentrations of similar magnitude to those observed in LCHF vent fluids (and also modern seawater) can be obtained by hydrothermal alteration of ultramafic rocks with Mo-free (Na, Ca) Cl aqueous solution. Thus, we conclude that alkaline hydrothermal fluids were likely similarly enriched in Mo prior to oxidation of the Earth’s atmosphere and ocean, providing localized Mo-rich geochemical environments capable of supporting Mo-dependent nitrogen fixation at currently recognized threshold concentrations.

A fungal endophyte increases plant resilience to low nutrient availabilities: a case of Fe acquisition in legumes.

Microbial inocula are considered a promising and effective alternative solution to the use of chemical fertilizers to support plant growth and productivity since they play a key role in the availability and uptake of nutrients. Here, the effect of a beneficial of a fungal root endophyte, Fusarium solani strain K (FsK), on nutrient acquisition efficiency of the legume Lotus japonicus was studied, and putative mode-of-action of the endophyte at a molecular level was determined. Plant colonization with the endophyte resulted in increased shoot and root fresh weight under Fe deficiency compared to control nutrient conditions. Plant inoculation with FsK was associated with a significant increase in macro- and micronutrient concentration in leaves at an early stage of endophyte inoculation and a replenishment of Fe content under prolonged iron starvation. The mechanistic basis of the plant growth promotion capabilities of the endophyte is exerted at the transcriptional level since we recorded changes in the expression levels of genes related to iron uptake in FsK-colonized plants under stress conditions compared to uninoculated plants. In addition, the observed changes in the ethylene biosynthesis-related genes suggest a possible implication of ethylene in the mode of action used by FsK to enhance plant response to nutrient stress conditions. Finally, we demonstrated that the endophyte possesses a reductive high-affinity Fe uptake system and identified a ferric reductase that was induced in planta under Fe deficiency conditions, indicating that this fungal Fe homeostasis mechanism may result in a benefit in nutrient acquisition for the plant as well.

Maize Grain Metabolite Profiling by NMR: Effects of Growing Year, Variety, and Cropping System.

Considering that maize (Zea mays L.) is a staple food for a large segment of the population worldwide, many attempts have been made to improve the nutritional value of its grain and at the same time to achieve sustainable cropping systems. The present study aimed to characterize the composition and nutritional value of maize grain as influenced by cropping system, genetic background (variety), and growing year using untargeted NMR metabolomics. The composition of both water- (sugars and polyols, organic acids, and amino acids) and liposoluble metabolites (free and esterified fatty acids, sterols, and lipids) extracted from the maize grain was determined. Multivariate statistical analyses (PCA and ANOVA) pointed to the growing year and the variety as the most important random and fixed factors, respectively, influencing the metabolite profile. The samples were separated along PC1 and PC3 according to the growing year and the variety, respectively. A higher content of citric acid and diunsaturated fatty acids and a lower content of tyrosine, trigonelline, and monounsaturated fatty acids was observed in the organic with respect to the conventional variety. The effect of the cropping system was overwhelmed by the random effect of the growing year. The results provide novel knowledge on the influence of agronomic practices on maize micronutrient contents.

Assessment of Elite Mulberry Genotypes for Fruit Traits and Biochemical Composition

This study aimed to identify the most promising mulberry genotypes for fruit production by evaluating fruit characteristics, biochemical traits and nutritional composition. Eight elite mulberry genotypes were selected from the mulberry germplasm unit at the Department of Sericulture, GKVK, Bengaluru. The saplings were raised and transplanted into the main field 90 days after planting, following a Randomized Complete Block Design (RCBD) with a spacing of 5 × 3 feet, with three replications per genotype. The results revealed that among the eight genotypes, ME-0006 exhibited superior fruit characteristics, with the highest values for fruit length (3.16 cm), fruit width (2.01 cm), fruit weight (3.02 g) and fruit yield per plant (166.55 g). Biochemical analyses indicated that ME-0220 had the highest total soluble solids (TSS) (19.71°B), carbohydrate content (166.49 mg/g), anthocyanin (38.41 mg/g), and zinc content (mg/100g). Genotype ME-0006 recorded the highest calcium content (153.80 mg/100 g), while MI-0014 showed the highest levels of phosphorus, potassium, and magnesium. Additionally, ME-0086 was notable for its higher content of micronutrients and vitamin C (34.17 mg/100 g). These findings may provide valuable insights for selecting mulberry genotypes with superior fruit yield and biochemical properties, which can be further utilized in breeding programs and commercial mulberry fruit cultivation.

Stability of metal ion complexes with the synthetic phytosiderophore proline-2'-deoxymugineic acid.

Adequate micronutrient concentrations in crops are essential for human health and agricultural productivity. However, 30% of plants growing on cultivated soils worldwide are deficient in iron (Fe). Because of low micronutrient bioavailability, graminaceous plants have evolved to exude small molecules, called phytosiderophores, into the soil environment, which strongly complex and promote uptake of trace elements. The development of a synthetic phytosiderophore, proline-2'-deoxymugeneic acid (PDMA), has been shown to promote Fe uptake in rice plants; however, its binding capabilities with other metals, which may impact the ability to promote the uptake of Fe and other trace nutrient metals commonly found in soils, remain unknown. We conducted spectrophotometric titrations to determine the stability constants (logK) of PDMA complexes with Mn(II), Co(II), Cu(II), Ni(II), and Zn(II). We determined that PDMA complex stability constants correlated with: (1) the hydrolysis constants of metal ions (logKOH) in complexes; (2) the ionic potential of complexed metals; and (3) the corresponding complex stability constants of other mugineic acid type phytosiderophores, as well as the trishydroxamate microbial siderophore DFOB. These correlations demonstrate the potential, and limitations, on our ability to predict the stability of phytosiderophore complexes with metal ions with different physicochemical properties and with potentially different coordination structures.

Preparation, Characterization, and Testing of Compost Tea Derived from Seaweed and Fish Residues

Non-aerated compost tea (CT) was prepared from compost derived from rockweed (Ascophyllum nodosum) and fish (cod, common ling, haddock, saithe) residues that fermented in water. Electrical conductivity, pH, concentrations of dry matter, ash, C, macronutrients (N, P, K, Ca, and Mg), and micronutrients (Cu, Fe, Mn, Mo, and Zn) of CT prepared under different fermentation conditions were measured. The effects of process factors, i.e., water/compost mass ratio (4.2–9.8 g/g) and fermentation time (4.2–9.8 days = 100–236 h), on the physicochemical properties of CT were quantified using quadratic polynomial models. CT obtained at optimal levels of process factors (4.2 g/g and 5.6 days = 134 h) was tested for lettuce seed germination and seedling growth. Diluted CT (25% CT + 75% ultrapure water) improved seedling growth while achieving a high germination percentage (97%).

Development of Iron and Zinc Biofortified Rice Variety for Nutrition Improvement in Bangladesh

Depleting micronutrients such as iron and zinc poses a serious risk to a population’s health in regions where nutrient-rich meals are unavailable, such as Bangladesh. We can engross the essential minerals using biofortified rice varieties enriched with essential minerals. We experimented to develop and evaluate a new high-yielding rice variety, Advanced Chemical Industries (ACI) dhan1, specifically for the rainy season in Bangladesh. We used high-yielding rice parent lines with high iron and zinc in the hybridization process, then grew and selected the resulting breeding lines during the rainy season of Bangladesh to identify the most suitable rice lines for the rainy season. The plant height and days to maturity traits were the same as shown in both cultivars, ACI dhan1 and Bangladesh Rice Research Institute (BRRI) dhan62 (standard check), which are 104 cm and 103 days, respectively. On the other hand, ACI dhan1 produced 6.05 tons per hectare, and BRRI dhan62 yielded 4.33 tons per hectare. A quality analysis of the grain quantified that ACI dhan1 contained 8.21% protein and 25.12% apparent amylose. Similarly, ACI dhan1 had very high levels of Zn (24.8 ppm) and Fe (9 ppm). We observed a more than 70% improvement in milling capabilities and head rice recovery. In proposed variety trials, the Seed Certification Agency of Bangladesh identified an average yield advantage of more than 10% for ACI dhan1 in 10 locations. National Seed Board, Bangladesh, released it as a candidate for high-iron and zinc-enriched rice variety and approved its extensive cultivation in Bangladesh. Due to its high micronutrient content, excellent agronomic performance, and non-sticky cooking quality, ACI dhan1 presents itself as a variety of choice in Bangladesh’s pursuit of food and nutrition security. Thus, the present study demonstrates the large achievement of biofortification by ACI dhan1 and hence promises to be a strong weapon in the battle against malnutrition.

Molecular protocol to develop β-carotene-biofortified rice events via molecular optimization

Providing food with nutrition and functionality is crucial for sustaining human life. Rice (Oryza sativa L.) is a representative staple crop with high carbohydrate content but low amounts of essential amino acids, micronutrients, and carotenoids such as provitamin A. To improve the nutritional quality, rice endosperm was biofortified to accumulate carotenoids such as β-carotene through genetic engineering (i.e., using synthetic carotenoid biosynthetic genes, a nonmammalian viral polycistronic sequence, and an optimized promoter and transit peptide) and high-throughput rice transformation (approximately 300 transgenic plants per construct). To facilitate the safety assessment of genetically modified food, molecular characterization was performed to select elite lines equipped with a single intergenic insertion of T-DNA, high transgene expression, in this case leading to high carotenoid content, and with phenotypic and compositional substantial equivalence. In this study, we present β-carotene-biofortified rice event candidate lines eligible for commercial use and a disclosed molecular protocol for the development of biotech rice crops.

Nutritional composition of gedi (Abelmoschus manihot) leaves powder in comparison to common natural galactagogue plants in Indonesia

Abstract. Winata GM, Hardinsyah H, Marliyati SA, Rimbawan R, Andrianto D. 2024. Nutritional composition of gedi (Abelmoschus manihot) leaves powder in comparison to common natural galactagogue plants in Indonesia. Biodiversitas 25: 2583-2589. Galactagogue is a substance believed to help initiate, maintain, and increase breast milk production. Low or no breast milk production and perceived insufficient milk are the most common reasons that cause a mother to stop breastfeeding earlier. To help this problem, natural galactagogue consumption is highly recommended. Gedi (Abelmoschus manihot (L.) Medik) plant is locally used in Indonesia as food ingredient and medicinal plant. The leaves have been believed for generations to increase breast milk production. This study aimed to evaluate the macro- and micronutrient content of gedi leaves powder, compared to torbangun (Coleus amboinicus) and katuk (Sauropus androgynous) leaves powder as common natural galactagogue plants in Indonesia. Clean fresh leaves were oven-dried and ground. Carbohydrates, crude fiber, protein, fat, ash, energy, water, vitamins A, B1, B2, B6, B9, C, E, and K, mineral calcium, iron, magnesium, sodium, zinc, phosphorus, and potassium were analyzed using standard methods. The analysis result showed that gedi leaves powder contained highest carbohydrate (51%), crude fiber (10.3%), vitamin K (1,110 µg/100 g), mineral magnesium (700 mg/100 g), sodium (89.6 mg/100 g), and calcium (2,671 mg/100 g) content, which were significantly different compared to torbangun and katuk leaves powder (P&lt;0.05). Total energy (344 kcal/100 g), protein (25%), ash (13.6%), zinc (4.8 mg/100 g), potassium (2,314 mg/100 g), and iron (8.9 mg/100 g) content of gedi leaves powder were between torbangun and katuk leaves powder. This study showed that gedi leaves powder had a high carbohydrate, crude fiber, vitamin K, and mineral, especially calcium and magnesium, and sufficient protein and energy content, compared to torbangun and katuk leaves powder as common natural galactagogue plants in Indonesia. Further research in the extraction, bioactive compound, and in vivo study has to be carried out to scientifically prove the galactagogue effects of gedi leaf powder.

Plasma volume is associated with micronutrient mass but not concentration in healthy US women of reproductive age

BackgroundPlasma transports nutrients and composes more than half of the volume of blood. A few prior studies suggest that plasma volume fluctuations may impact certain micronutrient concentrations. We hypothesized a slight negative correlation between plasma volume and micronutrient biomarkers throughout the menstrual cycle in healthy women of reproductive age (n = 45). MethodsThe study involved three visits during one menstrual cycle where fasting blood samples were taken to measure biomarker concentrations for zinc, copper, magnesium, manganese, iron, ferritin, retinol, and hemoglobin. A bolus dose of indocyanine green (ICG; equivalent to 0.25 mg.kg-1 of body weight) was injected to measure plasma volume. The total circulating micronutrient biomarker mass was calculated using the plasma volume and biomarker concentration. We used Spearman's correlation and fractional polynomial regression techniques to assess the relationship between plasma volume and biomarker concentration and mass. ResultsPlasma volume ranged from 1210 to 3520 mL. During all three visits, the correlation between micronutrient biomarker concentrations and plasma volume ranged from -0.05 to 0.10 (all P > 0.05); However, there was a strong positive correlation between biomarker mass and plasma volume, ranging from 0.26 to 0.95 (all P < 0.05). Five of the eight biomarkers examined (zinc, copper, magnesium, retinol, and hemoglobin) showed a correlation coefficient > 0.70 (P < 0.001) between mass and plasma volume. ConclusionOur findings indicate that biomarker concentrations are maintained across a range of plasma volume, suggesting that plasma volume may not be necessary to interpret micronutrient status in healthy non-pregnant women of reproductive age.

Genetically predicted circulating concentrations of micronutrients and risk of autoimmune thyroiditis: a Mendelian randomized study.

Micronutrients play pivotal roles in modulating various aspects of the immune response. However, the existing literature on the association between micronutrients and autoimmune thyroiditis (AIT) remains limited and contentious. To address this gap, we conducted Mendelian randomization (MR) to investigate potential links between genetically predicted concentrations of six micronutrients (Copper (Cu), Iron (Ir), Calcium (Ca), Vitamin D (VD), Vitamin C (VC), Zinc (Zn)) and the risk of AIT. Utilizing summary statistics from genome-wide association studies (GWAS) in individuals of European descent, we employed MR methodologies to elucidate the interplay between micronutrients and AIT. Three distinct MR techniques were employed: Inverse Variance Weighted (IVW), MR-Egger regression, and Weighted Median Estimator (WME). Additionally, we evaluated outcome heterogeneity using Cochran's Q statistic and assessed pleiotropy using the MR-Egger intercept. IVW analysis revealed no substantial evidence supporting a significant impact of genetically predicted micronutrient concentrations on AIT risk (Cu: OR = 0.918, P = 0.875; Ir: OR = 0.653, P = 0.264; Ca: OR = 0.964, P = 0.906; VD: OR = 0.717, P = 0.378; VC: OR = 0.986, P = 0.875; Zn: OR = 0.789, P = 0.539). Cochran's Q test for IVW indicated no notable heterogeneity. Moreover, the MR-Egger intercept method suggested the presence of horizontal pleiotropy between serum VC levels and AIT (MR-Egger intercept = -0.037, p = 0.026), while no such pleiotropy was observed for other micronutrients. Our MR analysis does not support a causal relationship between genetically predicted concentrations of six micronutrients (Cu, Ir, Ca, VD, VC, and Zn) and the risk of AIT.

Estimation of macro and micronutrient concentrations in ‘valencia’ orange leaves at different phenological stages using multispectral image analysis and multiple regression

ABSTRACT This study aimed at estimating the macro- and micronutrient concentrations in leaves of Valencia oranges (Citrus sinensis [L.] Osbeck) through multiple regression analysis using multispectral images and vegetation indices (VIs) selected through the stepwise regression method. The data were collected in a commercial orchard of Valencia oranges in El Barretal, Tamaulipas, Mexico. The leaf samples were analysed in a laboratory to determine the concentrations of N, P, K, Ca, Mg, Cu, Fe, Mn, and Zn using traditional chemical methods; the relative chlorophyll values were obtained using a chlorophyll metre (SPAD502 Plus). Multi-spectral images of the tree canopy were acquired using a UAV equipped with a multispectral camera with five wavelengths (blue, green, red, red edge, and near-infrared); based on these data, 85 VIs were calculated. To select the predictor variables that were most relevant for the model, 90 candidate variables were divided into three groups with 30 VIs grouped by nutrients based on the highest and lowest absolute values found in the correlation matrix. Heteroscedasticity and autocorrelation were also assessed through the Breusch-Pagan and Durbin-Watson tests, respectively. The selected variables were used in multiple regression analysis. The resulting models were validated by mean absolute error (MAE), root-mean-square error (RMSE), mean absolute percentage error (MAPE), and coefficient of determination ( R 2 ). The prediction models showed satisfactory results, with values R 2 between 0.79 and 0.95 and relatively low (<10) MAE and RMSE for all nutrients, except Fe ( < 30 ) in all phenological stages; MAPE values were lower than 0.5% for all nutrients. This study showed that multispectral imaging combined with multiple regression analysis effectively predicts nutrient levels in the leaves of Valencia oranges in various phenological stages. This study presents a new perspective on agricultural systems, offering an effective alternative to assess the nutritional conditions of crops.

Nutrient Status and Supplement Use During Pregnancy Following Metabolic Bariatric Surgery: A Multicenter Observational Cohort Study

IntroductionPregnant women with a history of metabolic bariatric surgery (MBS) are at high risk of developing nutrient deficiencies, leading to greater challenges to reach nutritional requirements. This study compared nutrient status of women using specialized “weight loss surgery” multivitamin supplementation (WLS-MVS) to those using standard supplementation (sMVS) during pregnancy following MBS.MethodsMulticenter observational cohort study including 119 pregnant women at 41.0 (18.5–70.0) months after Roux-en-Y gastric bypass (RYGB, n = 80) or sleeve gastrectomy (SG, n = 39). Routine blood samples were analyzed every trimester (T1, T2, T3), and micronutrient serum levels were compared between WLS-MVS and sMVS users.ResultsDuring pregnancy after RYGB, WLS-MVS users demonstrated higher serum concentrations of hemoglobin (7.4 [7.2, 7.5] vs. 7.0 [6.8, 7.3] mmol/L), ferritin (23.2 [15.0, 35.7] vs. 13.7 [8.4, 22.4] µg/L), and folic acid (31.4 [28.7, 34.2] vs. 25.4 [21.3, 29.4] nmol/L) and lower serum vitamin B6 levels (T1: 90.6 [82.0, 99.8] vs. 132.1 [114.6, 152.4] nmol/L) compared to sMVS users. Iron deficiencies and elevated serum vitamin B6 levels were less prevalent in the WLS-MVS group. During pregnancy after SG, WLS-MVS users showed higher serum vitamin D concentrations (89.7 [77.6, 101.8] vs. 65.4 [53.3, 77.4] nmol/L) and lower serum vitamin B1 concentrations (T2: 137.4 [124.2, 150.6] vs. 161.6 [149.0, 174.1] nmol/L, T3: 133.9 [120.1, 147.7] vs. 154.7 [141.9, 167.5] nmol/L) compared to sMVS users.ConclusionLow maternal concentrations of micronutrients are highly prevalent during pregnancy after MBS. The use of specialized multivitamin supplementation generally resulted in higher serum levels during pregnancy compared to standard supplementation. Future research is needed to investigate how supplementation strategies can be optimized for this high-risk population.Graphical