Chemical composition and fatty acid profile of several Mexican wild lupins

We have performed chemical proximate analysis and determined the oil fatty acid profile of seeds from Lupinus mexicanus Cerv. ex Lag.;Lupinus exaltatus Zucc.;Lupinus montanus H.B.K.;Lupinus stipulatus J. Agardh collected at various locations in four Mexican states. Protein and fiber content from lupin seeds ranged from 334 to 467 and 106 to 172 g/kg on dry weight basis, respectively. The oil content fluctuated from 57 g/kg for L. mexicanus to 115 g/kg for L. montanus. All lupin oils contained a high concentration of palmitic acid (C160) and linoleic acid (C182), ranging from 175 to 287 and 324 to 517 g/kg, respectively. The ratio of oleic (C181) to linoleic (C182) acid and total saturated to total unsaturated fatty acids ranged from 0.22 to 0.5 and 1.5 to 3.3, respectively. Erucic acid (C221) was not present in any of the lupin oils analyzed while eicosanoic acid (C200) was found only in L. mexicanus (Manalisco). Behenic acid (C220) was found in all oil samples of L. montanus, L. stipulatus and L. mexicanus oils. Thus, we conclude that the oil content and fatty acid profile of the Mexican lupins studied are similar to those already reported for most lupin oils, except for the absence of erucic acid and greater palmitic acid concentration found in our samples. © 2001 Academic Press

Chemical composition and antinutrient content of three Lupinus species from Jalisco, Mexico

In this study, the proximal chemical analysis and contents of antinutritional factors (lectins, antitrypsin activity, cyanogenic glycosides, alkaloids, phytates and α -galactosides) of Lupinus exaltatus, L. reflexus, and L. mexicanus seeds were determined. The seeds of these lupins comprised 384.1, 388.0, 367.0 g/kg protein, which contained all the essential amino acids for human beings except glutamine and asparagine in their seed protein. OnlyL. exaltatus was free from lectins. Trypsin inhibitor concentrations ranged from 1.12 to 2.05 TIU/mg. Cyanogenic glycosides were present at low concentrations in the studied lupins. Total alkaloid content ranged from 14.0 to 44.0 g/kg and phytate content ranged from 11.1 to 1.856 g/kg. The main α -galactosides found in seeds were raffinose, stachyose, verbacose and ajucose. Stachyose was the predominant sugar in the studied species. Therefore, these wild lupins could be considered a good source of protein after a suitable reduction in the content of alkaloids. © 2000 Academic Press

Functional Divergence in Shrimp Anti-Lipopolysaccharide Factors (ALFs): From Recognition of Cell Wall Components to Antimicrobial Activity

Antilipopolysaccharide factors (ALFs) have been described as highly cationic polypeptides with a broad spectrum of potent antimicrobial activities. In addition, ALFs have been shown to recognize LPS, a major component of the Gram-negative bacteria cell wall, through conserved amino acid residues exposed in the four-stranded beta-sheet of their three dimensional structure. In penaeid shrimp, ALFs form a diverse family of antimicrobial peptides composed by three main variants, classified as ALF Groups A to C. Here, we identified a novel group of ALFs in shrimp (Group D ALFs), which corresponds to anionic polypeptides in which many residues of the LPS binding site are lacking. Both Group B (cationic) and Group D (anionic) shrimp ALFs were produced in a heterologous expression system. Group D ALFs were found to have impaired LPS-binding activities and only limited antimicrobial activity compared to Group B ALFs. Interestingly, all four ALF groups were shown to be simultaneously expressed in an individual shrimp and to follow different patterns of gene expression in response to a microbial infection. Group B was by far the more expressed of the ALF genes. From our results, nucleotide sequence variations in shrimp ALFs result in functional divergence, with significant differences in LPS-binding and antimicrobial activities. To our knowledge, this is the first functional characterization of the sequence diversity found in the ALF family