Profile and Functional Properties of Seed Proteins from Six Pea (Pisum sativum) Genotypes

Extractability, extractable protein compositions, technological-functional properties of pea (Pisum sativum) proteins from six genotypes grown in Serbia were investigated. Also, the relationship between these characteristics was presented. Investigated genotypes showed significant differences in storage protein content, composition and extractability. The ratio of vicilin:legumin concentrations, as well as the ratio of vicilin + convicilin: Legumin concentrations were positively correlated with extractability. Our data suggest that the higher level of vicilin and/or a lower level of legumin have a positive influence on protein extractability. The emulsion activity index (EAI) was strongly and positively correlated with the solubility, while no significant correlation was found between emulsion stability (ESI) and solubility, nor between foaming properties and solubility. No association was evident between ESI and EAI. A moderate positive correlation between emulsion stability and foam capacity was observed. Proteins from the investigated genotypes expressed significantly different emulsifying properties and foam capacity at different pH values, whereas low foam stability was detected. It appears that genotype has considerable influence on content, composition and technological-functional properties of pea bean proteins. This fact can be very useful for food scientists in efforts to improve the quality of peas and pea protein products.     

Proteomic Analysis of Embryogenesis and the Acquisition of Seed Dormancy in Norway Maple (Acer platanoides L.)

The proteome of zygotic embryos of Acer platanoides L. was analyzed via high-resolution 2D-SDS-PAGE and MS/MS in order to: (1) identify significant physiological processes associated with embryo development; and (2) identify changes in the proteome of the embryo associated with the acquisition of seed dormancy. Seventeen spots were identified as associated with morphogenesis at 10 to 13 weeks after flowering (WAF). Thirty-three spots were associated with maturation of the embryo at 14 to 22 WAF. The greatest changes in protein abundance occurred at 22 WAF, when seeds become fully mature. Overall, the stage of morphogenesis was characterized by changes in the abundance of proteins (tubulins and actin) associated with the growth and development of the embryo. Enzymes related to energy supply were especially elevated, most likely due to the energy demand associated with rapid growth and cell division. The stage of maturation is crucial to the establishment of seed dormancy and is associated with a higher abundance of proteins involved in genetic information processing, energy and carbon metabolism and cellular and antioxidant processes. Results indicated that a glycine-rich RNA-binding protein and proteasome proteins may be directly involved in dormancy acquisition control, and future studies are warranted to verify this association.     

Effect of liming on boron nutrition of pea (Pisum sativum L.) and corn (Zea mays L.) grown in sequence in an acid Alfisol

A field experiment was conducted during 1986–87 on a sandy loam acid Alfisol of Barapani, Meghalaya, India to study the effect of liming on boron nutrition of pea and corn grown in a sequence. Lime and boron were applied to pea and their residual effect was studied on corn. Application of 1.5 kg B ha^–1 significantly increased the pod and stover yield of pea. A sharp yield depression occurred at higher B rates. Liming accentuated B deficiency in the absence of B treatment and it cured toxicity arising from excess B supply. A combination of B at 1.5 kg ha^–1 and lime at 3.0 t ha^–1 was optimum for pea, but this level of B application was insufficient to meet B requirements of succeeding corn. With higher rates of B fertilization, the residual effect of B on corn yield was significant. Concentration of B in shoot, pod, grain and stover of crops increased with the rate of B application. With increasing liming rate, B concentration decreased. Addition of B increased the hot-water soluble B in soil. The availability of native and added B decreased sharply with increasing liming rate.     

The influence of rate and time of nitrate supply on nitrogen fixation and yield in pea (Pisum sativum L.)

The influence of nitrate N supply on dry matter production, N content and symbiotic nitrogen fixation in soil-grown pea (Pisum sativum L.) was studied in a pot experiment by means of¹⁵N fertilizer dilution. In pea receiving no fertilizer N symbiotic nitrogen fixation, soil and seed-borne N contributed with 82, 13 and 5% of total plant N, respectively. The supply of low rates of nitrate fertilizer at sowing (starter N) increased the vegetative dry matter production, but not the seed yield significantly. Nitrogen fixation was not significantly decreased by the lower rates of nitrate but higher rates supplied at sowing reduced the nitrogen fixation considerably. Applying nitrate N at the flat pod growth stage increased the yield of seed dry matter and N about 30% compared to pea receiving no nitrate fertilizer. Symbiotic nitrogen fixation was reduced only about 11%, compared with unfertilized pea, by the lowest rate of nitrate at this application time. The pea very efficiently took up and assimilated the nitrate N supplied. The average fertilizer N recovery was 82%. The later the N was supplied the more efficiently it was recovered. When nitrate was supplied at the flat pod growth stage 88% was recovered, and 90% of this N was located in the seeds.     

Pea (Pisum sativum L.) peel waste carbon loaded with zirconium: study of kinetics,thermodynamics and mechanism of fluoride adsorption

ABSTRACT

Pea peel waste carbon loaded with zirconium is used as an engineered biochar material for adsorption of fluoride from aqueous solution. The prepared adsorbent was characterized and the material degradation kinetics were studied using thermogravimetric analysis. Adsorption kinetics follow both pseudo-second order and intra-particle diffusion model. Optimization of algorithm yielded Freundlich isotherm as the best fitting equation. Increment in solution temperature thermodynamically favors fluoride adsorption. Fluoride adsorption remains unaffected in presence of specific co-ions. Adsorbed fluoride could be successfully leached using 0.001 N NaOH and reusability of the material was tested up to tenth cycle of continuous operation.     

Stability of Cold-Pressed Oil from Commercial Indian Niger (Guizotia abyssinica (L.f.) Cass.) Seed as affected by Blending and Interesterification

Blending and interesterification of cold‐pressed oil from commercially available niger (Guizotia abyssinica (L.f.) Cass.) seeds was performed to improve its stability. The fatty acid composition of cold‐pressed niger seed oil (NSO) revealed that it contained a huge amount of polyunsaturated linoleic acid (69.2 %). NSO being rich in polyunsaturated fatty acids (PUFA) was susceptible to oxidation and hence was blended with saturated fatty acid (SFA) rich coconut oil (CNO) and monounsaturated fatty acid (MUFA) rich olive–pomace oil (OO) to enhance its stability. CNO contained a total of 91.3 % of SFA, while OO had oleic acid, C18:1 (74.3 %) as MUFA. Two blends of NSO with CNO and OO, i.e. NSO + CNO(B) and NSO + OO(B), were prepared in the ratio of 1:1. The blends were further interesterified using the lipase enzyme from Rhizomucor meihei and interesterified oils, i.e. NSO + CNO(I) and NSO + OO(I), were obtained. The oxidative stability of the oils was evaluated by incubating them at 37 °C and 55 % relative humidity (RH) for a period of 45 days. The peroxide values of NSO + CNO(B), NSO + OO(B), NSO + CNO(I) and NSO + OO(I) showed a reduction by 53.3, 42.6, 65.3 and 55.4 %, respectively, while the conjugated diene values showed a reduction by 75.0, 66.9, 76.7 and 75.3 %, respectively, as compared to NSO during the incubation period. This is probably the first report on the stability improvement of niger seed oil through blending and interesterification.