Characterization of Tunisian castor bean genotypes using SDS-PAGE of total seed storage proteins

Martin Vivodí­K,Lenka Petrovičová,Ezzeddine Saadaoui,Želmí­Ra Balážová,Zdenka Gálová

doi:10.5219/973

Abstract

Due to the chemical and physical properties of castor oil (Ricinus communis L.) that make it a valuable raw material for numerous industrial applications, including the production of biofuel, interest to develop more and better varieties has been increased. The objectives of this work, were to find out the level of genetic variability present in 56 Tunisian castor germplasm by using the electrophoretic profiles of total seed proteins with different molecular weights through SDS-PAGE. Fifty-six castor (Ricinus communis L.) genotypes were used in the present study. Seeds of castor were obtained from the University of Carthage, National Institute of Research in Rural Engineering, Waters and Forests (INRGREF), Regional Station of Gabès, Tunisia. Storage proteins were extracted from individual grains by the standard reference electrophoretic method by ISTA in the presence of sodium dodecyl sulfate (SDS-PAGE). The number of total scorable protein bands was twentynine as a result of SDS-PAGE technique but those that were not cosistent in reproducibility and showed occasional variation in sharpness and density were not considered. Out of twentynine polypeptide bands, 5 (18%) were commonly present in all accessions and considered as monomorphic, while 24 (82%) showed variations and considered as polymorphic. The size of the protein bands obtained through SDS-PAGE ranged from 30 to 180 kDa. On the basis of banding profiles of proteins of different kDa, gel was divided into zones A, B and C. The major protein bands were lied in zones A and B, while minor bands were present in zones C. The dendrogram tree demonstrated the relationship among the 56 Tunisian castor genotypes according to the similarity index, using UPGMA cluster analysis. The dendrogram was divided into three main clusters. Similarly the present study of genetic variability in the seed storage polypeptide determined by SDS-PAGE technique proved that it is fruitful to identify genetic diversity among accessions of castor.

Highlights

Castor bean (Ricinus communis L.), known as castor oil bean, mole bean and wonder tree, is a member of Spurge family (Euphorbiaceae) which is originated from tropical Africa and is currently cultivated as an oilseed crop and grown as an ornamental plant in many countries of Asia, Central and North America, Africa and Europe (Doan, 2004; Aslani et al, 2007).Castor bean has recently been highly rated as a source of raw material (oil) for biodiesel production, because beyond its high oil content (25 – 55%), it is a culture of great social appeal in Brazil by intensive use of workmanship in the field and allows for intercropping with other crops as beans, groundnuts or maize (Madail et al, 2007; Lacerda et al, 2014)
Seeds of castor were obtained from the University of Carthage, National Institute of Research in Rural Engineering, Waters and Forests (INRGREF), Regional Station of Gabès, Tunisia
The size of the protein bands obtained through SDS-PAGE ranged from 30 to 180 kDa

Summary

Introduction

Castor bean (Ricinus communis L.), known as castor oil bean, mole bean and wonder tree, is a member of Spurge family (Euphorbiaceae) which is originated from tropical Africa and is currently cultivated as an oilseed crop and grown as an ornamental plant in many countries of Asia, Central and North America, Africa and Europe (Doan, 2004; Aslani et al, 2007).Castor bean has recently been highly rated as a source of raw material (oil) for biodiesel production, because beyond its high oil content (25 – 55%), it is a culture of great social appeal in Brazil by intensive use of workmanship in the field and allows for intercropping with other crops as beans, groundnuts or maize (Madail et al, 2007; Lacerda et al, 2014). ABSTRACT The objectives of this work, were to find out the level of genetic variability present in 56 Tunisian castor germplasm by using the electrophoretic profiles of total seed proteins with different molecular weights through SDS-PAGE. Storage proteins were extracted from individual grains by the standard reference electrophoretic method by ISTA in the presence of sodium dodecyl sulfate (SDS-PAGE).

Results

Conclusion