Effect of thermal treatment on the extraction efficiency, physicochemical quality of Jatropha curcas oil, and biological quality of its proteins.

Jatropha curcas seeds are an important source of oil (5-60%), used to obtain biodiesel. The generated residual paste has a high concentration of proteins (50-55%); however, the seeds contain non-nutritional factors that limit their use. The objective of this work was to analyze the effect on the physicochemical properties of the oil obtained from J. curcas seeds subjected to different thermal treatments and to evaluate the biological quality of the proteins contained in the residual cake. The best extraction of oil (95%) was obtained after 10 h from roasted or boiled seeds. In the oil from roasted samples, the acid index increased significantly (p ≤ 0.05) with respect to the untreated sample, whereas the iodine index increased significantly (p ≤ 0.05) in the oil extracted from the boiled samples. With respect to the proximal chemical composition of the flour, roasting and boiling treatments allowed for greater oil extraction (97 and 92%), achieving, in turn, a higher content of proteins (59.56 and 58.5 g/100 g) and fiber (6.67 and 6.67 g/100 g), and lower activity of trypsin inhibitors (45 and 38%) and phytates (63 and 72%), respectively. According to the in vivo biological quality test, conducted on Wistar rats, the thermal treatments applied to the seeds improved digestibility (> 70%) and the protein efficiency index (PER). The thermal treatment allowed extracting more efficiently the oil and improved the quality of the proteins present in the residual paste.

High SNP diversity in the non-toxic indigenous Jatropha curcas germplasm widens the potential of this upcoming major biofuel crop species.

BACKGROUND AND AIMS: Jatropha curcas (jatropha) is an oil crop cultivated in (sub)tropical regions around the world, and holds great promise as a renewable energy source. However, efforts to fully commercialize jatropha are currently hampered by the lack of genetic diversity in the extant breeding germplasm, and by the toxicity of its seeds meaning that its seed cake cannot be used as a protein source in animal feed, among other constraints. In Mexico, the species' native range, there are jatropha plants whose seeds are used to prepare traditional meals. This non-toxic jatropha 'type' is considered to harbour low genetic variation due to a presumed domestication bottleneck and therefore to be of limited breeding value; yet, very little is known regarding its origin and genetic diversity. METHODS: Using genotyping-by-sequencing (GBS), we extensively genotyped both indigenous toxic and non-toxic jatropha collected along roads and home gardens throughout southern Mexico. KEY RESULTS: Single nucleotide polymorphism diversity in non-toxic jatropha is relatively high, particularly in northern Veracruz state, the probable origin of this germplasm. Genetic differences between toxic and non-toxic indigenous genotypes are overall quite small. A a genome-wide association study supported a genomic region (on LG 8, scaffold NW_012130064), probably involved in the suppression of seed toxicity. CONCLUSIONS: Conservation actions are urgently needed to preserve this non-toxic indigenous, relatively wild germplasm, having potential as a fuel feedstock, animal feed and food source among other uses. More generally, this work demonstrates the value of conservation genomic research on the indigenous gene pool of economically important plant species.

Somatic Mutations in Prostate Cancer: Closer to Personalized Medicine.

The molecular cause of prostate cancer (PCa) is still unclear; however, its progression involves androgen, PI3K/Akt, and PTEN signaling, as cycle and apoptotic pathways. Alterations in oncogenes and tumor suppressor genes as PIK3CA, BRAF, KRAS and TP53 are not very common. Recently, somatic mutations have been discovered in relation to cancer progression mainly in genes such as PIK3CA; however, little data has been described in PCa. Nowadays genetic tools allow us to investigate multiple details about the biological heterogeneity of PCa, to better understand the mechanisms of disease progression and treatment resistance. Therefore, if the most relevant somatic mutations were included during screening, we could identify the best treatment for the right patient, bringing us closer to personalized medicine. The main objective of this article is to provide a review of the principal somatic mutations that appear to have a relevant role in hormonal cancers, like prostate cancer.