Chickpea leaves as a vegetable green for humans: Evaluation of mineral composition

Chickpea (Cicer arietinum) is generally consumed as a seed food, being a good source of protein and other essential human nutrients. However, young chickpea leaves are also eaten as a cooked vegetable green in certain parts of the world and could be a useful source of dietary nutrients, especially in malnourished populations. Because little information is available on the mineral content of this food, we characterised leaf mineral concentrations in 19 diverse accessions of chickpea. Both desi and kabuli chickpea types were studied. All plants were greenhouse-grown and were fertilised daily with a complete mineral solution. Young, fully expanded leaves (fourth through seventh nodes from the apex) were harvested at both early and late vegetative stages. The leaves were dried, ashed and analysed for mineral concentrations. Macronutrient mineral (Ca, Mg, K, P) concentrations varied from 1.3-fold to 1.8-fold and micronutrient mineral (Fe, Zn, Mn, Cu, B, Ni) concentrations varied from 1.5-fold to 2.4-fold across all accessions. No major differences were observed in leaf mineral concentrations between the kabuli and desi types; mineral concentrations were generally lower in leaves collected at the later harvest date. Microscopic analyses demonstrated that all accessions contained crystal inclusions, suggestive of calcium oxalate crystals. Overall, chickpea leaves were found to be a good source of several minerals required by humans, and the levels of most of these minerals significantly exceeded those previously reported for spinach and cabbage

No evidence of regulation in root-mediated iron reduction in two Strategy I cluster-rooted Banksia species (Proteaceae)

Aims: Non-mycorrhizal species such as Banksia (Proteaceae) that depend on root exudates to acquire phosphorus (P) are prominent in south-western Australia, a biodiversity hotspot on severely P-impoverished soils. We investigated the consequences of an exudate-releasing P-mobilising strategy related to control of iron (Fe) acquisition in two Banksia species, B. attenuata R.Br. and B. laricina C. Gardner, that differ greatly in their geographical distribution and rarity. Methods: We undertook solution culture experiments to measure root-mediated Fe reduction (FeR) in non-cluster and cluster roots at four stages of cluster-root development, and whole root systems for plants grown at 2 to 300 μM Fe (as Fe-EDTA). As a positive control, we used Pisum sativum (cv. Dunn) to validate the FeR assay. Results: Unlike typical Strategy I species, both Banksia species showed no significant variation in FeR, for either cluster or non-cluster roots, when grown at a wide range of Fe supply. For roots of different developmental stages, we measured a range for B. attenuata cluster roots of 0.13 ± 0.03 to 1.29 ± 0.14 μmol Fe³⁺ reduced g⁻¹ FW h⁻¹ and 0.56 ± 0.11 to 1.10 ± 0.24 μmol Fe³⁺ reduced g⁻¹ FW h⁻¹ in non-cluster roots. Similarly, for B. laricina cluster-roots, FeR ranged from 0.22 ± 0.07 to 1.21 ± 0.37 μmol Fe³⁺ reduced g⁻¹ FW h⁻¹, and in non-cluster roots from 0.56 ± 0.11 to 0.71 ± 0.08 μmol Fe³⁺ reduced g⁻¹ FW h⁻¹. We also observed only minor differences for whole-root system FeR, and even though B. attenuata showed signs of leaf Fe deficiency in the 2 μM Fe treatment, its FeR was the lowest of both species across all treatments at 0.079 ± 0.009 μmol Fe³⁺ reduced g⁻¹ FW h⁻¹, compared with the fastest rate of 0.20 ± 0.014 μmol Fe³⁺ reduced g⁻¹ FW h⁻¹ for B. laricina in the 28 μM Fe treatment. Taking plants through a pulse from low to high Fe, then back to low Fe supply did not elucidate any significant response in FeR.: Conclusions: Although Fe acquisition is tightly controlled in the investigated Banksia species, such control is not based on regulation of FeR, which challenges the model that is commonly accepted for Strategy I species.Gregory R. Cawthray, Matthew D. Denton, Michael A. Grusak, Michael W. Shane, Erik J. Veneklaas, Hans Lamber

Use of a “super-child” approach to assess the vitamin A equivalence of Moringa oleifera leaves, develop a compartmental model for vitamin A kinetics, and estimate vitamin A total body stores in young Mexican children

Background: Worldwide, an estimated 250 million children <5 y old are vitamin A (VA) deficient. In Mexico, despite ongoing efforts to reduce VA deficiency, it remains an important public health problem; thus, food-based interventions that increase the availability and consumption of provitamin A–rich foods should be considered. Objective: The objectives were to assess the VA equivalence of 2H-labeled Moringa oleifera (MO) leaves and to estimate both total body stores (TBS) of VA and plasma retinol kinetics in young Mexican children