Comparative Studies on the Proteins From Seeds of Lupinus angustifolius L.

Abstract

The seeds of 99 genotypes of L. angustifolius were examined by electrophoresis on cellulose acetate and found to contain two major salt-extracted globulins, conglutins α and β, and a third minor globulin, conglutin γ. Dissociation with sodium dodecyl sulfate and electrophoresis on polyacrylamide gel showed variation in the number, proportion and molecular size of the subunits which constitute these proteins. This was confirmed by electrophoresis in polyacrylamide gel containing urea at acid pH. The globulins in the salt extracts of some of the seeds were subject to partial enzymic degradation unless conditions which inactivate proteolytic enzymes were used during extraction. Crude protein level of the seed meal, determined for many of the genotypes from their nitrogen content, varied from about 30 to 50%. Only 5-10% of this total protein was water-extracted albumins. Amino acid analysis showed that the albumin fraction contains higher levels of many of the essential amino acids including cystine and particularly methionine.

Isolamento da globulina majoritária, digestibilidade in vivo e in vitro das proteínas do tremoço-doce (Lupinus albus L.), var. Multolupa

“…Estudo comparativo de 100 amostras de sementes de tremoço de diferentes variedades e procedentes de 12 diferentes países mostrou variações de 30 a 50% de proteína total; contendo 60% das amostras de 32 a 38% de proteína, enquanto 28% apresentavam teores entre 38-44% de proteína [7,44]. % N 2 x 6,25), sendo 43,42% de globulinas, 10,77% de albuminas, 0,49% de prolaminas e 16,29% de glutelinas [33].…”

“…A observação da Figura 5 permite afirmar que a proteína é composta de subunidades na faixa de 20-70 kDa e que não há pontes dissulfeto na molécula. Esses resultados confirmam aqueles relatados por MELO et al [31] e BLAGROVE & GILLESPIE [7]. A recromatografia em coluna de Q-sepharose mostrou um único pico (resultados não mostrados).…”

“…Dentre as espécies pesquisadas podemos destacar o tremoço (Lupinus), por constituir-se em uma das mais ricas fontes de proteínas entre as sementes de leguminosas, em que teores variáveis entre 28 e 51% de proteína tem sido reportado para diferentes variedades [7,11,13,24,33,45]. Estudos de caracterização das proteínas das sementes de tremoço demonstram diferenças consideráveis em função da variedade, método de extração e do procedimento físi-co-químico utilizado [6,7,18,34]. A presença de substân-1 Digestibilidade das proteínas de tremoço, Neves, Silva Jr. & Silva cias antinutricionais e tóxicas tem sido substancialmente reduzida por meio de cruzamentos intervariedades, em especial as variedades "doces".…”

Isolation of conglutin δ, a sulphur‐rich protein from the seeds of Lupinus angustifolius L.

“…G., unpublished) showed that conglutin 6 is present in each species, although rarely resolved from conglutin a by electrophoresis on cellulose acetate. Therefore, because Blagrove et al6,7 show no evidence either for very broad conglutin a bands or a fourth electrophoretic species, it is assumed that conglutin 6 was not precipitated by the salting-out procedure they used. Thus, it is not surprising that the 2s protein has attracted little attention although it represents both a significant proportion of the total protein and up to 75% of the sulphur amino acids in the globular protein fraction of lupin seed.…”

Lupin Globulins

“…After the pioneering studies by Joubert in South Africa during the 1950's (Joubert, 1955a(Joubert, , 1955b(Joubert, , 1955c(Joubert, , 1956(Joubert, , 1957 and others (Naismith, 1955;Petri et al, 1955;Gerritsen, 1956), an interest in the isolation and characterization of lupin seed proteins was rekindled during the 1970's by B1agrove and Gillespie in Australia (Gillespie and Blagrove, 1974;Gillespie, 1975: Gillespie andB1agrove, 1975;Blagrove et ai., 1976: Elleman, 1977: Blagrove and Gillespie, 1978: Gillespic et al, 1978B1agrove et aI., 1980) and by Cerlctti and Duranti in Italy (Duranti and Cerletti. 1979).…”