Quality of Lupinus albus L. (white lupin) seed: extent of genotypic and environmental effects

Fingerprinting alkaloids for traceability: Semi-untargeted UHPLC-MS/MS approach in raw lupins as a case study

Lupin seeds are recognized for their nutritional value and potential health benefits, but they contain also a significant amount of alkaloids, an anti-nutritive class of compounds, which vary significantly in composition within and between species due to environmental factors. In this study, we developed a predictive multi-experiment approach using ultra-high performance liquid chromatography coupled with triple quadrupole with linear ionic trap tandem mass spectrometry (UHPLC-QqQ-LIT-MS/MS) for comprehensive alkaloid profiling and geographical classification of Lupinus albus L. samples originating from four different Italian regions. Six targeted quinolizidine alkaloids were detected and 21 other alkaloids were putatively identified. Hierarchical Cluster Analysis (HCA) and partial least squares discriminant analysis (PLS-DA) were applied to explore the data structure and successfully classify samples according to their geographical origin. The data demonstrate the efficacy of the developed approach in providing valuable insights in alkaloid profiles of lupin seeds and their potential as markers for geographical traceability.

Environmental conditions affect the nutritive value and alkaloid profiles of Lupinus forage: Opportunities and threats for sustainable ruminant systems

The identification of crops that simultaneously contribute to the global protein supply and mitigate the effects of climate change is an urgent matter. Lupins are well adapted to nutrient-poor or contaminated soils, tolerate various abiotic stresses, and present relevant traits for acting as ecosystem engineers. Lupins are best studied for their seeds, but their full foraging potential needs further evaluation. This study evaluated the effects of location and sowing date on forage production, proximate composition, and the detailed mineral and alkaloid profiles of three species of Lupinus (L. albus cv. Estoril, L. angustifolius cv. Tango, and L. luteus cv. Cardiga). Sowing date and location and their interaction with the plant species significantly affected the vast majority of measured parameters, emphasizing the effects of climate and soil conditions on these crops. The relatively high crude protein and in vitro digestibility support the potential of the lupin species studied as sustainable forage protein sources in diets for ruminant animals. The content of individual essential macro and trace elements was below the maximum tolerable levels for cattle and sheep. Lupanine, smipine, and sparteine were the most abundant quinolizidine alkaloids in L. albus cv. Estoril, lupanine, and sparteine in L. angustifolius cv. Tango, and lupinine, gramine, ammodendrine, and sparteine in L. luteus cv. Cardiga. Based on the maximum tolerable levels of total quinolizidine alkaloid intake, the dietary inclusion of forages of L. albus cv. Estoril and L. angustifolius cv. Tango does not pose a risk to the animals, but the high alkaloid content of L. luteus cv. Cardiga may compromise its utilization at high levels in the diet. Overall, the results reveal a high potential for lupins as protein forage sources well adapted to temperate regions and soils with lower fertility, with a relevant impact on livestock sustainability in a climate change era.

Morphological and physiological properties of lupine nodule bacteria (Bradyrhizobium lupini) when grown on a typical urban soil

In the conducted studies, the moorphological and physiological properties of nodule bacteria of lupine were studied. Lupine plants were grown under the conditions of a microfield experiment on a typical medium loamy urban soil. In the study, a pure culture of Bradyrhizobium lupini was isolated. Then, the morphological properties of nodule bacteria cells and the chemical composition of cell membranes of nodule bacteria were determined. The acid resistance and physiological properties of lupine nodule bacteria were also determined, as well as the ratio of Bradyrhizobium lupini to antibiotics. All studies were carried out according to generally accepted methods. The results of the research showed that during the cultivation of lupine on a typical urban soil, nodule bacteria Bradyrhizobium lupini were isolated, which can be characterized as gram-negative, non-spore-forming rods that do not exhibit amylolytic activity. It was revealed that the rhizobia of nodule bacteria are not acid-resistant. Nodule bacteria turned out to be the least resistant to polymyxin, then to levomycetin, and Bradyrhizobium lupini showed the greatest resistance to tetracycline.

Lupin as a Source of Bioactive Antioxidant Compounds for Food Products

Four species of lupin (white lupin, yellow lupin, blue lupin and Andean lupin) are widely cropped thanks to the excellent nutritional composition of their seeds: high protein content (28-48 g/100 g); good lipid content (4.6-13.5 g/100 g, but up to 20.0 g/100 g in Andean lupin), especially unsaturated triacylglycerols; and richness in antioxidant compounds like carotenoids, tocols and phenolics. Particularly relevant is the amount of free phenolics, highly bioaccessible in the small intestine. However, the typical bitter and toxic alkaloids must be eliminated before lupin consumption, hindering its diffusion and affecting its nutritional value. This review summarises the results of recent research in lupin composition for the above-mentioned three classes of antioxidant compounds, both in non-debittered and debittered seeds. Additionally, the influence of technological processes to further increase their nutritional value as well as the effects of food manufacturing on antioxidant content were scrutinised. Lupin has been demonstrated to be an outstanding raw material source, superior to most crops and suitable for manufacturing foods with good antioxidant and nutritional properties. The bioaccessibility of lupin antioxidants after digestion of ready-to-eat products still emerges as a dearth in current research.

Bioactive Nutrient Retention during Thermal-Assisted Hydration of Lupins

Lupin, an arid pulse, is gaining popularity as a super food due to its superior nutritional properties. However, it has not been considered for large scale thermal processing, e.g., canning. The present work evaluated the best time/temperature combination to hydrate lupins for canning with minimum losses of bioactive nutrients, pre-biotic fibre, and total solids during hydration. The two lupin species showed a sigmoidal hydration behaviour, which was adequately modelled by the Weibull distribution. The effective diffusivity, D_eff, increased from 7.41 × 10^-11 to 2.08 × 10^-10 m²/s for L. albus and 1.75 × 10^-10 to 1.02 × 10^-9 m²/s for L. angustifolius with increasing temperature, namely, from 25 °C to 85 °C. The lag phase decreased from 145 min to 56 min in L. albus and 61 min to 28 min in L. angustifolius. However, based on the effective hydration rate, reaching the equilibrium moisture, minimum loss of the solids, and prebiotic fibre and phytochemicals, 200 min hydration at 65 °C can be regarded as the optimum temperature of hydration. The findings are thus relevant for designing the hydration protocol to achieve the maximum equilibrium moisture content and yield with the minimum loss of solids (phytochemicals and prebiotic fibres) for L. albus and L. angustifolius.

Development of an HPLC-MS/MS Method for the Determination of Alkaloids in Lupins

Lupin alkaloids (LAs) represent a class of toxic secondary metabolites in plants, in particular in Lupinus spp.; they are produced as a defense mechanism due to their strong bitter taste and are very dangerous for human and animals. In this work, a sensitive and reliable high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analytical method for the identification and quantification of thirteen lupin alkaloids was developed and validated according to FDA guidelines. Efficient extraction and clean-up steps, carried out by solid-phase extraction, were finely tuned on the basis of the characteristics of the analytes and lupin samples, providing good selectivity with minimized matrix interference. The effectiveness of the method was proven by the satisfactory recovery values obtained for most of the analytes and a matrix effect ≤23% for all tested levels. In addition, a sensitive and reliable determination of the target compounds was obtained; LOQs were between 1 and 25 µg Kg^-1, i.e., below the requested maximum levels (<200 mg Kg^-1). The method was applied to evaluate the LAs profile in different batches of raw L. albus L. samples, varying in size and across farming treatments.

Effect of Debittering with Different Solvents and Ultrasound on Carotenoids, Tocopherols, and Phenolics of Lupinus albus Seeds

Lupin seeds represent a rich nutritional source of bioactive compounds, including antioxidant molecules such as carotenoids, tocopherols, and phenolics. However, before consumption, the lupin seeds must be debittered in order to remove their bitter and toxic alkaloids. This study analyzed the impact on the bioactive compounds of Lupinus albus seeds of a recent time- and water-saving debittering method, which employs alternative washing solutions (0.5% or 1% of either NaCl or citric acid), with or without the assistance of ultrasound. The results were compared with those of two control methods using water or a NaCl solution. The sonication, when it was significant, led to a large loss of bioactive compounds, which was most likely due to its extraction capability. The seeds that were debittered without ultrasound presented high concentrations of tocopherols (172.8-241.3 mg/kg DM), carotenoids (10.9-25.1 mg/kg DM), and soluble-free (106.9-361.1 mg/kg DM), soluble-conjugated (93.9-118.9 mg/kg DM), and insoluble-bound (59.2-156.7 mg/kg DM) phenolics. The soluble-free fraction showed the greatest loss after a prolonged treatment. Overall, debittering with citric acid or NaCl preserved the highest concentration of antioxidant compounds by shortening the treatment time, thus preventing extensive leaching.

Indole and quinolizidine alkaloids from blue lupin leach to agricultural drainage water

Phytotoxins are produced in plants including agricultural crops. Lupins and other plants of the Fabaceae family produce toxic alkaloids. These alkaloids have been studied in food and feed, however, the environmental fate of alkaloids produced by cultivated lupins is largely unknown. Therefore, we conducted an agricultural field experiment to investigate the occurrence of indole and quinolizidine alkaloids in lupin plant tissues, soil, soil pore water and in drainage water. During the field experiment, alkaloids were regularly quantified (median concentrations) in lupin (13-8.7 × 10³ ng/g dry weight (dw)), and topsoils at depth 0-5 cm (0.1-10 ng/g dw), and depth 15-30 cm (0.2-8.5 ng/g dw), soil pore water (0.2-7.5 ng/L) and drainage water samples (0.4-18 ng/L). Lupanine was the dominant alkaloid in all collected samples. Cumulative amounts of alkaloids emitted via drainage water were around 0.1-11 mg/ha for individual alkaloids over one growing season. The total cumulative amount of alkaloid in drainage water was 14 mg/ha, which is a very small amount compared to the mass of alkaloid in the lupin biomass (11 kg/ha) and soil (0.02 kg/ha). Nearly half of the alkaloids were exported in the drainage water during high flow events, indicating that alkaloids transport preferentially via macropores. These findings indicate that drainage from lupin cultivated areas contribute to surface water contamination. The environmental and ecotoxicological relevance of alkaloids as newly identified aquatic micropollutants in areas with agricultural activities have yet to be assessed.

The Influence of Dehulling on the Nutritional Quality of Lupine Seeds (Lupinus albus L.) and the Effect of Their Use in the Feed of Laying Quails on the Live Performance and Quality of Eggs

Lupinus albus seeds from low-alkaloid varieties are a valuable alternative source of protein for reducing the dependence on soybean meal for the feeding of monogastric animals. Therefore, the aim of this research was to evaluate the dehulling influence of lupine seeds (L. albus, cv. Amiga) and the effect of their use in the laying quails feed on live performance and egg quality. A total of 200 laying quails (Coturnix japonica), with an age of 10 weeks, were randomly assigned to five experimental groups (five replicates/group). Each group was randomly assigned to one of five dietary treatments: the control group (C) diet was based on soybean meal, while the experimental groups received either 200 g/kg (WLS₂₀) or 250 g/kg (WLS₂₅) of whole lupine seeds in their diets, or 200 g/kg (DLS₂₀) or 250 g/kg (DLS₂₅) of dehulled lupine seeds in their diets. The results show that by dehulling the lupine seeds, the nutritional value of the seeds increased. The use of dehulled lupine seeds in the diet of laying quails did not affect the live performance (egg production, feed intake, feed conversion ratio), yolk cholesterol content, and physico-chemical quality indices of the eggs, compared with control. The presence of dehulled lupine seeds in the diet improved the nutritional quality of the yolk lipids because of the increase in the content of polyunsaturated fatty acids. Thus, the lipid quality indices of the yolk became more favorable to consumer health because of an increase in the h/H ratio (hypocholesterolemic/Hypercholesterolemic FA) and a decrease in the atherogenic index and thrombogenic index values. The higher content in carotenoids also contributed to the higher nutritional quality of the eggs obtained by lupine utilization. In conclusion, dehulling of lupine seeds had a positive influence on the nutritional quality of the seeds, the live performance of quails, and the quality of eggs.

Quantitative Control of Early Flowering in White Lupin (Lupinus albus L.)

White lupin (Lupinus albus L.) is a pulse annual plant cultivated from the tropics to temperate regions for its high-protein grain as well as a cover crop or green manure. Wild populations are typically late flowering and have high vernalization requirements. Nevertheless, some early flowering and thermoneutral accessions were found in the Mediterranean basin. Recently, quantitative trait loci (QTLs) explaining flowering time variance were identified in bi-parental population mapping, however, phenotypic and genotypic diversity in the world collection has not been addressed yet. In this study, a diverse set of white lupin accessions (n = 160) was phenotyped for time to flowering in a controlled environment and genotyped with PCR-based markers (n = 50) tagging major QTLs and selected homologs of photoperiod and vernalization pathway genes. This survey highlighted quantitative control of flowering time in white lupin, providing statistically significant associations for all major QTLs and numerous regulatory genes, including white lupin homologs of CONSTANS, FLOWERING LOCUS T, FY, MOTHER OF FT AND TFL1, PHYTOCHROME INTERACTING FACTOR 4, SKI-INTERACTING PROTEIN 1, and VERNALIZATION INDEPENDENCE 3. This revealed the complexity of flowering control in white lupin, dispersed among numerous loci localized on several chromosomes, provided economic justification for future genome-wide association studies or genomic selection rather than relying on simple marker-assisted selection.

Chemical Composition, Tocopherol and Carotenoid Content of Seeds from Different Andean Lupin (Lupinus mutabilis) Ecotypes

Andean lupin (Lupinus mutabilis) seeds are appreciated for their high protein and lipid contents and have potential applications as ingredients in food, cosmetic, and pharmaceutical industries. Nevertheless, the information about the seed composition (especially in lipophilic antioxidants) of ecotypes from distinct cropping areas is currently limited. Thus, the aim of the present research was to assess the morphological characteristics, chemical composition, tocopherol and carotenoid contents of the seeds of 33 Andean lupin ecotypes from different Peruvian regions, along with three L. albus, one L. angustifolius and one L. luteus controls. Significant differences were noted among the Andean ecotypes for all analyzed features. The protein, lipid and ash contents were 32.0-46.9, 13.6-18.6 and 2.7-4.4 g/100 g dry matter (DM), respectively. The seeds were rich in tocopherols (172.1-249.8 mg/kg DM; γ-tocopherol was 98% of total tocols) and low in carotenoids (0.69-2.89 mg/kg DM). Debittering increased the tocopherol content (227.0-378.2 mg/kg DM), probably because of the soluble components loss, although the carotenoid concentration remained unchanged. The Andean lupins had higher protein, lipid and tocopherol contents than L. albus and L. angustifolius; the L. luteus values were within the L. mutabilis range. These results suggest that L. mutabilis harbors nutritional characteristics that are well suited to modern food trends.

Peptides from Extruded Lupin (Lupinus albus L.) Regulate Inflammatory Activity via the p38 MAPK Signal Transduction Pathway in RAW 264.7 Cells

In this study, protein was extracted from extruded lupin and submitted to gastroduodenal digests to obtain lupin peptides, which were characterized using ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). After this, IQDKEGIPPDQQR (IQD), the lupine peptide monomer characterized after UPLC-MS/MS, was screened out by macrophage inflammatory cytokine production assay. RNA-sequencing analysis was performed to explore the mechanisms underlying the anti-inflammatory activity associated with this peptide. The results indicated that lupin peptides effectively inhibited the lipopolysaccharide-induced overproduction of proinflammatory mediators. IQD inhibited the production of tumor necrosis factor-α, interleukin (IL)-6, IL-1β, and monocyte chemoattractant protein-1 by 51.20, 38.52, 44.70, and 40.43%, respectively. RNA-sequencing results showed that IQD inhibited the inflammatory response by regulating the gene expression of the p38 mitogen-activated protein kinase pathway and inhibiting downstream inflammatory cytokines. These bioactive peptides may be used to develop new ingredients for anti-inflammatory nutritional supplements.

Development of PCR-based markers and whole-genome selection model for anthracnose resistance in white lupin (Lupinus albus L.)

White lupin (Lupinus albus L.) is a high-protein grain legume crop, grown since ancient Greece and Rome. Despite long domestication history, its cultivation remains limited, partly because of susceptibility to anthracnose. Only some late-flowering, bitter, low-yielding landraces from Ethiopian mountains displayed resistance to this devastating disease. The resistance is controlled by various genes, thereby complicating the breeding efforts. The objective of this study was developing tools for molecular tracking of Ethiopian resistance genes based on genotyping-by-sequencing (GBS) data, envisaging linkage mapping and genomic selection approaches. Twenty GBS markers from two major quantitative trait loci (QTLs), antr04_1/antr05_1 and antr04_2/antr05_2, were converted to PCR-based markers using assigned transcriptome sequences. Newly developed markers improved mapping resolution around both anthracnose resistance loci, providing more precise QTL estimation. PCR-based screening of diversified domesticated and primitive germplasm revealed the high specificity of two markers for the antr04_1/antr05_1 locus (TP222136 and TP47110) and one for the antr04_2/antr05_2 locus (TP338761), highlighted by simple matching coefficients of 0.96 and 0.89, respectively. Moreover, a genomic selection approach based on GBS data of a recombinant inbred line mapping population was assessed, providing an average predictive ability of 0.56. These tools can be used for preselection of candidate white lupin germplasm for anthracnose resistance assays.

Scientific opinion on the risks for animal and human health related to the presence of quinolizidine alkaloids in feed and food, in particular in lupins and lupin-derived products

The European Commission asked EFSA for a scientific opinion on the risks for animal and human health related to the presence of quinolizidine alkaloids (QAs) in feed and food. This risk assessment is limited to QAs occurring in Lupinus species/varieties relevant for animal and human consumption in Europe (i.e. Lupinus albus L., Lupinus angustifolius L., Lupinus luteus L. and Lupinus mutabilis Sweet). Information on the toxicity of QAs in animals and humans is limited. Following acute exposure to sparteine (reference compound), anticholinergic effects and changes in cardiac electric conductivity are considered to be critical for human hazard characterisation. The CONTAM Panel used a margin of exposure (MOE) approach identifying a lowest single oral effective dose of 0.16 mg sparteine/kg body weight as reference point to characterise the risk following acute exposure. No reference point could be identified to characterise the risk of chronic exposure. Because of similar modes of action for QAs, the CONTAM Panel used a group approach assuming dose additivity. For food, the highest mean concentration of Total QAs (TotQAs) (i.e. the 6 most abundant QAs) was found in lupin seed samples classified as 'Lupins (dry) and similar-'. Due to the limited data on occurrence and consumption, dietary exposure was calculated for some specific scenarios and no full human health risk characterisation was possible. The calculated margin of exposures (MOEs) may indicate a risk for some consumers. For example, when lupin seeds are consumed without a debittering step, or as debittered lupin seeds high in QA content and when 'lupin-based meat imitates' are consumed. For horses, companion and farm animals, other than salmonids, the available database on adverse effects was too limited to identify no-observed-adverse-effect levels and/or lowest-observed-adverse-effect levels and no risk characterisation was possible. For salmonids, the CONTAM Panel considers the risk for adverse effects to be low.

Bioconversion of alkaloids to high-value chemicals: Comparative analysis of newly isolated lupanine degrading strains

This work explores the potential for development of a lupanine valorization process evaluating different isolated microorganisms for their capacity to metabolize the alkaloid. Ecotoxicological assessment demonstrated that lupanine is toxic for Vibrio fischeri and Daphnia magna exhibiting EC₅₀ values of 89 mg L^-1 and 47 mg L^-1 respectively, while acting both as growth inhibitor for a monocotyledonous and as promoter for a dicotyledonous plant. Among the eight aerobic and anaerobic strains isolated and identified Rhodococcus rhodochrous LPK211 achieved 81% removal for 1.5 g L^-1 lupanine, while no end-products were detected by NMR constituting a promising microorganism for lupanine biodegradation. Moreover, Rhodococcus ruber LPK111 and Rhodococcus sp. LPK311 exhibited 66% and 71% of removal respectively, including potential formation of lupanine N-oxide. Pseudomonas putida LPK411 reached 80% of lupanine removal and generated three fermentation products potentially comprising 17-oxolupanine and lupanine derivatives with open ring structures enabling the development of alkaloid valorization processes.

Evaluation of total polyphenol content and antioxidant capacity of different verity lupin seeds

Legumes, including lupins, beans, lentil and chickpea, are one of the most important crops in the world because of their nutritional quality. Lupin seeds have been used as human food and animal feed since ancient times. It was known that antioxidant photochemical in foods have many health benefits including prevention of various diseases associated with oxidative stress such as cancer, cardiovascular disease, neuro-degeneration and diabetes. Lupin grains are rich sources of complex carbohydrates, protein, vitamins and minerals. Antioxidants can be found naturally in foods. Total polyphenols content and antioxidant activity were measured in four varieties of lupin, namely in white lupin, blue lupin, yellow lupin and Mutabilis lupin species. A majority of antioxidants naturally present in foods occur in phenolic structures and especially in flavonoid structures. The content of the total polyphenols was determined by using the Folin-Ciocalteu reagent (FCR). Antioxidant activity was measured by using a compound DPPH˙ (2.2-diphenyl-1-picrylhydrazyl). In the present experiment according to the average contents of total polyphenols (TPC) in dry matter of lupin seeds there was the following line: L. Angustifolius (blue) lupin (696.212 mg GAE.100g-1) > L. Albus (white) lupin (614.13 mg GAE.100g-1) > L. Luteus (yellow) lupin (467.78 mg GAE.100g-1) > L. Mutabilis (pearl) lupin (367.36 mg GAE.100g-1). Based on the measured values of total antioxidant capacity (TAC) of lupin samples can be classified as follows: L. Albus (white) lupin (43.44%) >L. Angustifolius (blue) lupin (38.27%) >L. Luteus (yellow) lupin (22.29%) >L. Mutabilis (Pearl) lupin (20.80%). The relationship of antioxidant capacity with total polyphenolic was discussed. According to used statistical analyzes. Correlation between the phenolic contents and antioxidant capacity was significantly positive (r = 0.88). Our results confirmed that legumes can be a good source of bioactive compounds in the human nutrition. The main objective of the present work was to evaluated the content of total polyphenols and an antioxidant capacity of four Lupine species.