Effect of dehulling and germination on the functional properties of grass pea (Lathyrus sativus) flour.

The compositional, bioactive, functional, pasting, and thermal characteristics of native, dehulled, and germinated grass pea flour were examined. Germination significantly improved the protein content and bioactive properties while simultaneously reducing total carbohydrate and fat levels. However, dehulling increased the fat content, foaming, and emulsion properties. Dehulling and germination significantly increased (p < 0.05) the functional properties by improving flowability and cohesiveness. Although processing methods enhance functional properties, the pasting properties of dehulled and germinated flours differ significantly (p < 0.05) from the native flour. The X-ray diffraction patterns indicate a reduction in percentage crystallinity in germinated flours. Overall, the study suggests that the dehulling and germination processes enhanced the quality of grass peas by improving nutritive value and functional attributes.

Critical Sites of Serine Acetyltransferase in Lathyrus sativus L. Affecting Its Enzymatic Activities.

LsSAT2 (serine acetyltransferase in Lathyrus sativus) is the rate-limiting enzyme in biosynthesis of ß-N-oxalyl-l-α,ß-diaminopropionic acid (ß-ODAP), a neuroactive metabolite distributed widely in several plant species including Panax notoginseng, Panax ginseng, and L. sativus. The enzymatic activity of LsSAT2 is post-translationally regulated by its involvement in the cysteine regulatory complex in mitochondria via interaction with ß-CAS (ß-cyanoalanine synthase). In this study, the binding sites of LsSAT2 with the substrate Ser were first determined as Glu290, Arg316, and His317 and the catalytic sites were determined as Asp267, Asp281, and His282 via site-directed/truncated mutagenesis, in vitro enzymatic activity assay, and functional complementation of the SAT-deficient Escherichia coli strain JM39. Furthermore, the C-terminal 10-residue peptide of LsSAT2 is confirmed to be critical to interact with LsCAS, and Ile336 in C10 peptide is the critical amino acid. These results will enhance our understanding of the regulation of LsSAT2 activities and the biosynthesis of ß-ODAP in L. sativus.

Contrasting ß-ODAP content correlates with stress gene expression in Lathyrus cultivars.

Lathyrus sativus, commonly known as grass pea, is a nutrient-rich pulse crop with remarkable climate-resilient attributes. However, wide use of this nutritious crop is not adopted owing to the presence of a non-protein amino acid ß-N-oxalyl-l-α,ß-diaminopropionic acid (ß-ODAP), which is neurotoxic if consumed in large quantities. We conducted a de novo transcriptomic profiling of two ODAP contrasting cultivars, Pusa-24 and its somaclonal variant Ratan, to understand the genetic changes leading to and associated with ß-ODAP levels. Differential gene expression analysis showed that a variety of genes are downregulated in low ß-ODAP cultivar Ratan and include genes involved in biotic/abiotic stress tolerance, redox metabolism, hormonal metabolism, and sucrose, and starch metabolism. Several genes related to chromatin remodeling are differentially expressed in cultivar Ratan. ß-ODAP biosynthetic genes in these cultivars showed differential upregulation upon stress. ODAP content of these cultivars varied differentially upon stress and development. Physiological experiments indicate reduced relative water content and perturbed abscisic acid levels in the low ODAP cultivar. Altogether, our results suggest that the low ODAP cultivar may have a reduced stress tolerance. The dataset provides insight into the biological role of ODAP and will be helpful for hypothesis-driven experiments to understand ODAP biosynthesis and regulation.

Towards establishment of a plant-based model to assess the novel anti-cancerous lead molecule(s): An in silico, in vivo and in vitro assessment of some potential anti-cancerous drugs on Lathyrus sativus L.

The drug development process is one of the important aspects of medical biology. The classical lead identification strategy in the way of drug development based on animal cell is time-consuming, expensive and involving ethical issues. The following study aims to develop a novel plant-based screening of drugs. Study shows the efficacy of certain anti-cancerous drugs (Pemetrexed, 5-Fluorouracil, Methotrexate, Topotecan and Etoposide) on a plant-based (Lathyrus sativus L.) system. Two important characteristics of cancer cells were observed in the colchicine-treated polyploid cell and the callus, where the chromosome numbers were unusual and the division of cells were uncontrolled respectively. With increasing concentration, the drugs significantly reduced the mitotic index, ploidy level and callus growth. Increasing Pemetrexed concentration decreased the plant DHFR activity. A decrease in total RNA content was observed in 5-FU and Methotrexate with increasing concentrations of the drugs. Etoposide and Topotecan inhibited plant topoisomerase II and topoisomerase I activities, which was justified through plasmid nicking and comet assay, respectively. Molecular and biochemical study revealed similar results to the animal system. The in silico study had been done, and the structural similarity of drug binding domains of L. sativus and human beings had also been established. The binding site of the selected drugs to the domains of plant target proteins was also determined. Experimental results are significant in terms of the efficacy of known anti-cancerous drugs on the plant-based system. The proposed assay system is a cost-effective, convenient and less time-consuming process for primary screening of anti-cancerous lead molecules.

Field phenotyping and quality traits of grass pea genotypes in South Italy.

BACKGROUND: Grass pea (Laithyrus sativus L.) is a rustic plant whose seeds are rich in polyphenols and antioxidants, and it has been consumed as food by human beings since ancient times. This study was conducted in Italy between 2017and 2019 to evaluate, under field conditions, the stability of seed yield, biomass and 1000-seed weight (THS) and to assess the antioxidant composition and activity of 11 grass pea accessions. RESULTS: Analysis of variance revealed significant effects of the environment, accession and accession × environment (A × E) on the yield, above-ground biomass and THS. We found that the environment (year) and A × E explained 52.61% and 23.76% of the total seed yield variation, respectively. No relationship was observed between the yield and the total protein of seeds. Most grass pea accessions showed sensitivity to frost conditions that occurred in the third growing season. The total phenolic content ranged from 50.51 to 112.78 mg 100 g-1 seeds and antioxidant activity ranged from 0.576 to 0.898 mmol Trolox equivalents 100 g-1 seeds and from 0.91 to 1.6 mmol Fe2+  100 g-1 seeds in 2,20-azinobis-3-ethylbenzothiazoline-6-sulfonic acid and ferric-reducing antioxidant power, respectively. Among the accessions, the 'Campi Flegrei' and 'di Castelcività' showed the best performance with the highest yield and stability, phenolic content and superior antioxidant activity. CONCLUSION: The results showed that the yield of grass pea was mainly influenced by different climate conditions. This variability in yield, phenolic content and antioxidant activity among different accessions could help breeders and farmers select high-performance accessions for cultivation. © 2020 Society of Chemical Industry.

Role of abscisic acid in modulating drought acclimation, agronomic characteristics and ß-N-oxalyl-L-α,ß-diaminopropionic acid (ß-ODAP) accumulation in grass pea (Lathyrus sativus L.).

BACKGROUND: ß-N-oxalyl-l-α,ß-diaminopropionic acid (ß-ODAP) is a physiological indicator in response to drying soil. However, how abscisic acid (ABA) modulates ß-ODAP accumulation and its related agronomic characteristics in drought stressed grass pea (Lathyrus sativus L.) continue to be unclear. The present study aimed to evaluate the effects of ABA addition on drought tolerance, agronomic characteristics and ß-ODAP content in grass pea under drought stress. RESULTS: Exogenous ABA significantly promoted ABA levels by 19.3% and 18.3% under moderate and severe drought stress, respectively, compared to CK (without ABA, used as control check treatment). ABA addition activated earlier trigger of non-hydraulic root-sourced signal at 69.1% field capacity (FC) (65.5% FC in CK) and accordingly prolonged its operation period to 45.6% FC (49.0% FC in CK). This phenomenon was mechanically associated with the physiological mediation of ABA, where its addition significantly promoted the activities of leaf superoxide dismutase, catalase and peroxidase enzymes and the biosynthesis of leaf proline, simultaneously lowering the accumulation of malondialdehyde and hydrogen peroxide under moderate and severe stresses. Interestingly, ABA application significantly increased seed ß-ODAP content by 21.7% and 21.3% under moderate and severe drought stress, but did not change leaf ß-ODAP content. Furthermore, ABA application produced similar shoot biomass and grain yield as control groups. CONCLUSION: Exogenous ABA improved the drought adaptability of grass pea and promoted the synthesis of ß-ODAP in seeds but not in leaves. Our findings provide novel insights into the agronomic role of ABA in relation to ß-ODAP enrichment in grass pea subjected to drought stress. © 2021 Society of Chemical Industry.

Biocatalytic Production of Aldehydes: Exploring the Potential of Lathyrus cicera Amine Oxidase.

Aldehydes are a class of carbonyl compounds widely used as intermediates in the pharmaceutical, cosmetic and food industries. To date, there are few fully enzymatic methods for synthesizing these highly reactive chemicals. In the present work, we explore the biocatalytic potential of an amino oxidase extracted from the etiolated shoots of Lathyrus cicera for the synthesis of value-added aldehydes, starting from the corresponding primary amines. In this frame, we have developed a completely chromatography-free purification protocol based on crossflow ultrafiltration, which makes the production of this enzyme easily scalable. Furthermore, we determined the kinetic parameters of the amine oxidase toward 20 differently substituted aliphatic and aromatic primary amines, and we developed a biocatalytic process for their conversion into the corresponding aldehydes. The reaction occurs in aqueous media at neutral pH in the presence of catalase, which removes the hydrogen peroxide produced during the reaction itself, contributing to the recycling of oxygen. A high conversion (>95%) was achieved within 3 h for all the tested compounds.

Effect of heat treatment on the structure and stability of Grass pea (Lathyrus sativus) protein isolate/Alyssum homolocarpum seed gum nanoparticles.

In the present study, Grass pea protein isolate (GPPI)- Alyssum homolocarpum seed gum (AHSG) complex nanoparticles were formed through two fabrication methods and their physicochemical properties, structure and stability against sodium chloride and different pHs were investigated. Type 1 particles were formed by creating GPPI nanoparticles, and then coating them with AHSG; while Type 2 particles were fabricated through the heat treatment of GPPI-AHSG complexes at 85 °C for 15 min. The preparation methods did not influence the magnitude of electrical charges on biopolymer particles. The particle size analysis revealed that Type 2 particles had lower mean diameter (d = 360.20 nm) compared to Type 1 particles (d = 463.22 nm). Structural properties of Type 1 and Type 2 particles were determined using Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometry (XRD), Differential scanning calorimetry (DSC), Atomic force microscopy (AFM), and transmission electron microscopy (TEM). Hydrogen bonding, electrostatic and hydrophobic interactions were the main driving forces contributed to the formation of both GPPI-AHSG complex particles. Assessments of morphological and structural properties also indicated that both Type 1 and 2 particles had spherical shapes and heat treatment increased the ordered intermolecular structures in biopolymer particles. Type 2 particles had higher denaturation temperature and better pH and salt stability when compared to Type 1 particles. These results indicate that thermal treatment was effective for the fabrication of stable GPPI-AHSG complex nanoparticles.

Development and physicochemical characterization of a new grass pea (Lathyrus sativus L.) miso.

BACKGROUND: Western consumers interest in Eastern fermented foods has been growing, due to their nutritional and healthy properties. In this study, new sweet misos and salty misos were produced using grass pea (Lathyrus sativus L.) - traditional Portuguese legume from local producers - to promote its consumption and preservation. The evolution of the new misos was evaluated in comparison to traditional miso (made from soybean), through analysis of the chemical composition, colour, texture and linear viscoelastic behaviour. RESULTS: Throughout the fermentation process, the ascorbic acid and phenolic compounds content - with important nutritional value - increased in all misos, mainly in misos produced using grass pea, besides, grass pea sweet miso presented the fastest evolution and darkest colour. The texture parameters (firmness and adhesiveness) of misos decreased over time: grass pea sweet miso showed the highest firmness reduction (51.63 N to 6.52 N) and soybean sweet miso the highest adhesiveness reduction (27.76 N to 3.11 N). Viscoelastic moduli also decreased, reflecting a reduction in the degree of internal structuring for all misos. However, grass pea misos presented more structured internal systems with faster maturation kinetics than soybean misos, for which stabilization started earlier. CONCLUSION: Two innovative misos were developed from grass pea. After 4 months, the texture parameters and viscoelastic moduli for grass pea misos, were similar to the control misos made from soybean, showing that grass pea can be used as a raw material to produce a sustainable miso with potentially healthy properties. © 2020 Society of Chemical Industry.

Copper­containing amine oxidase purified from Lathyrus sativus as a modulator of human neutrophil functions.

Over the last few decades, copper­containing amine oxidase (Cu­AO) from vegetal sources, and belonging to the class of diamine oxidase, has been documented to exhibit beneficial effects in both in vivo and ex vivo animal models of inflammatory or allergic conditions, including asthma­like reaction and myocardial or intestinal ischemia­reperfusion injuries. The aim of the present study was to assess the potential of vegetal Cu­AO as an anti­inflammatory and an antiallergic agent and to clarify its antioxidant properties. In cell­free systems, the reactive oxygen species and reactive nitrogen species scavenging properties of Cu­AO that is purified from Lathyrus sativus were investigated. Its effect on the formyl­methionyl­leucyl­phenylalanine peptide (fMLP)­activated cellular functions of human neutrophils were subsequently analyzed. The obtained results demonstrated that Cu­AO is not a scavenger of superoxide or nitric oxide, and does not decompose hydrogen peroxide. However, it inhibits the fMLP­dependent superoxide generation, elastase release and cell migration, and interferes with the process of calcium flux, supporting the idea that plant Cu­AO can interact with human neutrophils to modulate their inflammatory function. Therefore, the importance of these properties on the possible use of vegetal Cu­AO to control inflammatory conditions, particularly intestinal inflammation, is discussed in the current study.

The role of Lathyrus sativus flower surface wax in short-range attraction and stimulant for nymph laying by an adult viviparous aphid.

Aphis craccivora Koch (Hemiptera: Aphididae) is an important pest of Lathyrus sativus L. plants, and causes retarded plant growth and loss of seed production. The insect sucks cell sap from flowers and lays nymphs on flowers. Hence, an attempt has been made to observe whether flower surface wax compounds (alkanes and free fatty acids) from two cultivars (BIO L 212 Ratan and Nirmal B-1) of L. sativus could act as short-range attractant and stimulant for nymph laying by adult viviparous females. The n-hexane extracts of flower surface waxes were analyzed by TLC, GC-MS and GC-FID analyses. Twenty one and 22 n-alkanes between n-C12 and n-C36 were detected in BIO L 212 Ratan and Nirmal B-1, respectively; whereas 12 free fatty acids between C12:0 and C22:0 were identified in both cultivars. Pentadecane and tridecanoic acid were predominant n-alkane and free fatty acid, respectively. One flower equivalent surface wax of both cultivars served as short-range attractant and stimulant for nymph laying through Y-tube choice experiments and I-tube viviparity assays, respectively, by adult viviparous females. A synthetic blend of nonacosane, tridecanoic acid and linoleic acid, and a synthetic blend of tetradecane, pentadecane, nonacosane, tridecanoic acid and linoleic acid resembling in amounts as present in one flower equivalent surface wax of BIO L 212 Ratan and Nirmal B-1, respectively, served as short-range attractant and stimulant for nymph laying by adult viviparous females. This study suggests that both these blends could be used in lures in the development of baited traps in pest management programmes.

Sensory properties of yellow pea and macadamia honeys from conventional and flow hive extraction methods.

BACKGROUND: The process of harvesting honey is time consuming and labor intensive. A new system, the Flow Frame, has drastically simplified the harvesting process, enabling honey to be extracted directly from the hive with minimal processing. The sensory profile of honey is influenced, first, by botanical origin and subsequently by processing and storage parameters. A reduction in harvest processing may thus influence the sensory profile of honey harvested from FFs compared to that of honey produced from conventional processing. To test this hypothesis, two monofloral honeys (macadamia and yellow pea) were harvested from FFs, or by conventional honey extraction. Sensory profiling using conventional descriptive analysis was carried out for each floral source with an experienced trained panel. RESULTS: The two monofloral honeys harvested using the FF system had significantly (p < 0.05) higher floral and cleaner aftertaste sensory scores than the honey extracted using commercial (C) methods that involve the use of heat and centrifugation. CONCLUSION: The flow system retains honey's natural sensory properties compared to harvesting methods that require heat and centrifugation. © 2019 Society of Chemical Industry.

A convenient and robust protocol for preparation of ODAP-free Lathyrus sativus protein.

The present study aimed to develop a protocol for easy removal of ß-ODAP neurotoxin by converting it into its isomer α-ODAP (reported to be less toxic) followed by its separation from the protein fraction in pH dependent manner. Use of ß-mercaptoethanol prevented aggregate formation and increased solubility of the prepared Lathyrus sativus protein. Validation of ODAP removal by paper chromatography and mass spectrometry indicated the robustness of the protocol. Removal of ODAP and presence of high antioxidants and homoarginine content can enable Lathyrus sativus to be an alternate source of protein, as well as have other health benefits, including benefits for patients with cardiovascular diseases.

Linking a rapid throughput plate-assay with high-sensitivity stable-isotope label LCMS quantification permits the identification and characterisation of low ß-L-ODAP grass pea lines.

BACKGROUND: Grass pea (Lathyrus sativus) is an underutilised crop with high tolerance to drought and flooding stress and potential for maintaining food and nutritional security in the face of climate change. The presence of the neurotoxin ß-L-oxalyl-2,3-diaminopropionic acid (ß-L-ODAP) in tissues of the plant has limited its adoption as a staple crop. To assist in the detection of material with very low neurotoxin toxin levels, we have developed two novel methods to assay ODAP. The first, a version of a widely used spectrophotometric assay, modified for increased throughput, permits rapid screening of large populations of germplasm for low toxin lines and the second is a novel, mass spectrometric procedure to detect very small quantities of ODAP for research purposes and characterisation of new varieties. RESULTS: A plate assay, based on an established spectrophotometric method enabling high-throughput ODAP measurements, is described. In addition, we describe a novel liquid chromatography mass spectrometry (LCMS)-based method for ß-L-ODAP-quantification. This method utilises an internal standard (di-13C-labelled ß-L-ODAP) allowing accurate quantification of ß-L-ODAP in grass pea tissue samples. The synthesis of this standard is also described. The two methods are compared; the spectrophotometric assay lacked sensitivity and detected ODAP-like absorbance in chickpea and pea whereas the LCMS method did not detect any ß-L-ODAP in these species. The LCMS method was also used to quantify ß-L-ODAP accurately in different tissues of grass pea. CONCLUSIONS: The plate-based spectrophotometric assay allows quantification of total ODAP in large numbers of samples, but its low sensitivity and inability to differentiate α- and ß-L-ODAP limit its usefulness for accurate quantification in low-ODAP samples. Coupled to the use of a stable isotope internal standard with LCMS that allows accurate quantification of ß-L-ODAP in grass pea samples with high sensitivity, these methods permit the identification and characterisation of grass pea lines with a very low ODAP content. The LCMS method is offered as a new 'gold standard' for ß-L-ODAP quantification, especially for the validation of existing and novel low- and/or zero-ß-L-ODAP genotypes.

An Improved HILIC HPLC-MS/MS Method for the Determination of ß-ODAP and Its α Isomer in Lathyrus sativus.

ß-N-Oxalyl-l-α,ß-diaminopropionic acid (ß-ODAP) is a non-protein amino acid present in Lathyrus sativus (grass pea) and other Lathyrus species, in parallel with its nontoxic isomer, α-ODAP. When consuming grass pea for several months as staple food, ß-ODAP may cause neurolathyrism, a motor neuron degeneration syndrome. Therefore, the independent quantification of both ODAP isomers instead of only the total amount in grass pea allows the identification of less toxic varieties and the development of tools to support breeding for improving grass pea quality. In this work, a simple and fast HPLC-MS/MS method was developed without sample derivatization, using a hydrophilic interaction chromatography (HILIC) column and an isocratic gradient of eluents for 18 min, which allowed the determination of both α- and ß-ODAP. The proposed method was fully validated and applied to the determination of α- and ß-ODAP contents in a diverse collection of 107 grass pea accessions representative of the main grass pea-growing geographical regions in the world, with the prompt identification of contrasting accessions. ß-ODAP content in the analyzed grass pea samples ranged from 0.45 ± 0.02 to 6.04 ± 0.45 mg g-1. The moderate correlation found between α- and ß-ODAP contents (0.65) in this collection reinforces the importance of the independent quantification of both ODAP isomers.

Lathyrus sativus Originating from Different Geographical Regions Reveals Striking Differences in Kunitz and Bowman-Birk Inhibitor Activities.

Grass pea (Lathyrus sativus L.) is an important legume commonly grown in arid and semi-arid regions. This protein-rich legume performs well even under harsh environmental conditions and is considered to be a strategic famine food in developing countries. Unfortunately, its potential usage is greatly limited as a result of the presence of antinutritional factors, including the neuroexcitatory amino acid ß-N-oxalyl-l-α,ß-diaminopropionic acid (ß-ODAP) and protease inhibitors. ß-ODAP is responsible for a neurodegenerative syndrome that results in the paralysis of lower limbs, while protease inhibitors affect protein digestibility, resulting in reduced growth. Concerted research efforts have led to development of grass pea cultivars with reduced ß-ODAP content. In contrast, very little information is available on the protease inhibitors of L. sativus. In this study, we have conducted biochemical characterization of 51 L. sativus accessions originating from different geographical regions. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analyses of seed globulins and prolamins revealed striking similarity in their protein profile, although geographic-specific variations in profiles was also evident. Measurement of Bowman-Birk chymotrypsin inhibitor (BBi) and Kunitz trypsin inhibitor (KTi) activities in accessions revealed striking differences among them. Amino acid sequence alignment of grass pea BBi and KTi revealed significant homology to protease inhibitors from several legumes. Real-time polymerase chain reaction analysis demonstrated high-level expression of BBi and KTi in dry seeds and weak expression in other organs. Our study demonstrates substantial variation in BBi and KTi among grass pea accessions that could be exploited in breeding programs for the development of grass pea lines that are devoid of these antinutritional factors.

[Research in Motor Neuron Diseases Caused by Natural Substances: Focus on Pathological Mechanisms of Neurolathyrism].

Diseases of the motor-conducting system that cause moving disability affect socio-economic activity as well as human dignity. Neurolathyrism, konzo, and amyotrophic lateral sclerosis-parkinsonism-dementia complex (ALS-PDC) have attracted researchers to study the pathology of motor neuron (MN) diseases such as ALS. I have been studying neurolathyrism, which is caused by overconsumption of a legume grass pea (Lathyrys sativus L.). Among people who consume the legume as a food staple, many developed life-long paraparesis in their legs. ß-N-oxalyl-l-α,ß- diaminopropionic (l-ß-ODAP; BOAA), contained in this plant, is a neurotoxic analog of l-glutamic acid. We have clarified that in addition to the causal involvement of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) type glutamatergic receptor in MN death, a toxic role of group I metabotropic glutamate receptors as well as transient receptor potential channels were involved in the MN insult by l-ß-ODAP using primary MN culture. We have also established a neurolathyrism rat model by repeated, peripheral l-ß-ODAP treatment to newborn rats under mild stress. Rats showing hind-leg paraparesis with an incidence rate of around 25% were useful to study the in vivo pathology of MN disease. MNs of these rats were greatly decreased at their lumbo/sacral segments at various ages. Intra-parenchymal hemorrhage was consistently observed in paraparetic rats but not in cripple-free, treated rats. MN were depleted even at an acute period around bleeding spots, suggesting catastrophic neuro-vascular-glial interaction in this MN disease. Summaries of konzo and ALS-PDCs studies are also introduced.

Reduction of ß-ODAP and IP6 contents in Lathyrus sativus L. seed by high hydrostatic pressure.

Grass pea (Lathyrus sativus L.) seeds contain an endogenous neurotoxic non-proteinogenic amino acid, ß-N-oxalyl-l-α,ß-diaminopropionic acid (ß-ODAP), a major limiting factor-for their human consumption. Furthermore, phytate (IP6), a well-known antinutrient is present in concentration capable of hindering bioavailability of iron (Fe), zinc (Zn), calcium (Ca), phosphorus (P) and other micronutrients from the seeds. Due to the reported capability of high hydrostatic pressure (HHP) to reduce the content of certain antinutritional/toxic agents in seeds and grains, the impact of HHP on the reduction of ß-ODAP and IP6 were investigated. The contents of ß-ODAP of accessions from different regions in Ethiopia were found to be in the range of 51.94 to 806.52 mg/100 g. Accession (GF1- Alemu, AK) exhibiting the highest ß-ODAP content was selected for HHP treatment in soaked and batter forms using Central Composite Face Centered Design of experiments. The best HHP conditions in respect to ß-ODAP reduction were also applied to the accession (GP-240038) with the lowest ß-ODAP-content, a genetically improved variety (Wassie) and a variety from Germany (GR). The HHP treatment at 600 MPa for 25 min of seeds soaked for 6 h and 12 h exhibited the maximum reduction of ß-ODAP (232.11 mg/100 g) and IP6 (21.11 mg/100 g) respectively. The combined incremental effect of pressure and soaking time resulted in a more significant (p ≤ .001) reduction in both compounds than the interaction of pressure with holding time (p ≤ .05). A reduction of ß-ODAP from 36.00 to 71.22% by soaked-HHP treatment was observed. ß-ODAP reductions were always higher for soaked compared to batter grass pea seeds. IP6 contents after HHP treatment ranged from 33.65 mg/100 g to nill. It can be concluded that pressure, soaking and holding time as well as the grass pea seed accession/variety had great impact on molecular structure changes, enhancement of enzyme activity and reduction in ß-ODAP and IP6 content.

Stability of Vegetal Diamine Oxidase in Simulated Intestinal Media: Protective Role of Cholic Acids.

Food biogenic amines, in particular, histamine, are often responsible for various enteric and vascular dysfunctions. Several years ago, the oral administration of copper-containing diamine oxidase (DAO), also called histaminase, able to oxidatively deaminate biogenic amines, had been suggested as a food supplement to control food allergy and enteric dysfunctions. This report is aimed to generate a global image on the behavior of orally administrated DAO dosage forms in the intestinal tract. The catalytic stability of DAO from Lathyrus sativus seedlings in various simulated intestinal media with different pH and containing different association of cholic acids, pancreatic proteases, bicarbonate, lipids, or alcohol was investigated. Cholic acids and lipids protected the enzyme in the simulated intestinal fluids. However, they were not able to protect against the inhibitory effect of 24-36% (v/v) ethanol. These observations may be relevant for oral administration of enzymes as food supplements or therapeutic bioactive agents.

Identification and Characterization of ß-Lathyrin, an Abundant Glycoprotein of Grass Pea ( Lathyrus sativus L.), as a Potential Allergen.

Grass pea, a protein-rich, high-yielding, and drought-tolerant legume, is used as food and livestock feed in several tropical and subtropical regions of the world. The abundant seed proteins of grass pea are salt-soluble globulins, which can be separated into vicilins and legumins. In many other legumes, the members of vicilin seed proteins have been identified as major allergens. However, very little information is available on the allergens of grass pea. In this study, we have identified an abundant 47 kDa protein from grass pea, which was recognized by immunoglobulin E (IgE) antibodies from sera drawn from several peanut-allergic patients. The IgE-binding 47 kDa protein was partially purified by affinity chromatography on a Con-A sepharose column. Matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry analysis of the 47 kDa grass pea protein revealed sequence homology to 47 kDa vicilin from pea and Len c 1 from lentil. Interestingly the grass pea vicilin was found to be susceptible to pepsin digestion in vitro. We have also isolated a cDNA encoding the grass pea 47 kDa vicilin (ß-lathyrin), and the deduced amino acid sequence revealed extensive homology to several known allergens, including those from peanut and soybean. A homology model structure of the grass pea ß-lathyrin, generated using the X-ray crystal structure of the soybean ß-conglycinin ß subunit as a template, revealed potential IgE-binding epitopes located on the surface of the molecule. The similarity in the three-dimensional structure and the conservation of the antigenic epitopes on the molecular surface of vicilin allergens explains the IgE-binding cross-reactivity.