Variation of Jatropha curcas seed oil content and fatty acid composition with fruit maturity stage

Abstract

Seed oil production in Jatropha seeds through different maturity stages have been investigated. In order to meet the high demand of oil (feedstock) for large scale biodiesel production, increasing oil content or output in Jatropha seeds is required. Jatropha fruits were harvested at four different maturity stages and the seeds were analysed for oil content. The seed oil was analysed for fatty acid profile. Results from four different geographical locations investigated namely; Mmadinare, Thamaga, Maun and Shashe, have shown a similar trend in lipid accumulation in Jatropha seeds as the fruits mature from green to brown dry. However, maximum oil content in seeds varies with geographical location. Accumulation of oil in Jatropha seeds during maturation follows a parabolic trend and reaches its peak when fruits are yellow. Oil yield in Jatropha seed kernels ranges from 38.7% to 45.8% for the four maturity stages investigated. Overall results have revealed that harvesting Jatropha fruits when they are yellow increases seed oil output by 6-9% when compared to harvesting the fruits when they are brown dry. There is a relationship between the trend in fatty acid composition in Jatropha seed oil and seed oil content trend during fruit maturation. Based on the trend of unsaturated fatty acids in Jatropha seed oil, particularly linoleic and oleic acids, it can be deduced that reduction of seed oil content from yellow brown to brown dry stage is a result of breakdown of some of the unsaturated fatty acids.

Changes in Fatty Acids Content in Organic Rosehip (Rosa spp.) Seeds during Ripening

“…The second dominant saturated fatty acid in rosehip seeds was found to be stearic acid ( Table 3 ), which agreed with the findings published by Barros et al [ 25 ]. Our results show that the stearic acid content in the samples ranged from 0.975% to 2.76%.…”

“…It has been documented that unsaturated (MUFAs + PUFAs) fatty acids are chemically unstable and easily oxidized [ 25 ], therefore, a high amount of these fatty acids in rosehip seed oil makes it susceptible to oxidation as well as degradation. In addition, it can be deduced that reduction of fat content in the seed samples during ripening stage V is the result of the breakdown of some unsaturated fatty acids.…”

Lipid Characteristics of Mango Seed Kernel Oil as Affected by Different Ripening Stages of Fruit

“…Overall, the quantities of all the unsaturated fatty acids showed a steady decrease with fruit maturity. This aligns with the submission of [37] that observed decrease in the unsaturated fatty acid content of Jatropha seed oil as fruit maturation advance and associated it to the chemical instability of unsaturated fatty acids (easily oxidized), therefore making the oil susceptible to oxidation and degradation. It was also observed that the difference in quantity of unsaturated fatty acids to saturated fatty acids was significantly higher in unripe fruit oil compared with the ripe one.…”

Transcriptome Analysis and Identification of Lipid Genes in Physaria lindheimeri, a Genetic Resource for Hydroxy Fatty Acids in Seed Oil

“…The ESA in Tung oil is synthesized by an FADX, a conjugase X also derived from FAD2 [ 79 ]. Although the major FAs in Jatropha oil are 18:1 and 18:2, there are 1–2% of ESAs in seed TAG [ 80 ], suggesting that Jatropha seeds have a weak conjugase activity. The possibility exists that Jatropha acyltransferases, including JcLPAT2, acylate ESA into TAG.…”