Nontoxic oil preparation from Jatropha curcas L. seeds by an optimized methanol/n-hexane sequential extraction method

Published Date
Industrial Crops and Products
March 2017, Vol.97:308–315, doi:10.1016/j.indcrop.2016.12.034

• Author 

• Yunyun He ^a,b,1
• Tong Peng ^a,b,1
• Yanfang Guo ^a,b
• Shushu Li ^a,b
• Yiran Guo ^c
• Lin Tang ^a,b
• Fang Chen ^a,b,,

• aKey Laboratory of Bio-resources and Eco-environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, PR China
• bNational and Local Joint Engineering Laboratory for Energy Plant Bio-oil Production and Application, Chengdu, PR China
• cThe School of Biological Science and Medical Engineering, Beihang University, Beijing, PR China

Received 1 October 2016. Revised 7 December 2016. Accepted 20 December 2016. Available online 31 December 2016. 

Highlights

• •
  A feasible methanol/n-hexane sequential extraction method for producing non-toxic oil from Jatropha curcas seeds is proposed with a high oil recovery.
• •
  The method uses whole Jatropha curcas seeds as the plant material.
• •
  The method utilizes response surface methodology to optimize the conditions of the first extraction step for phorbol esters.
• •
  Phorbol esters enriched fraction is obtained to the maximum by this method.
• •
  A rapid and sensitive detection method for phorbol esters content by ultra-performance liquid chromatography is proposed.

Abstract

Ultrasound-assisted extraction (UAE) of phorbol esters (PEs) from Jatropha curcas L. (JC) seed oil using methanol as the extraction solvent was optimized by response surface methodology (RSM). Jatropha curcas L. seed oil is an excellent feedstock for biodiesel production, in which the presence of major toxic factor (phorbol esters) has limited its industrial applications. The aim of this work is to prepare the nontoxic oil from Jatropha curcas L. whole seeds with the first phorbol esters removal step and the second oil extraction step. The Box-Behnken design was applied to optimize three key parameters in the first phorbol esters removal step including temperature (X₁, °C), extraction time (X₂, min) and liquid-to-solid ratio (X₃, mL:g) for achieving a high extraction efficiency and minimal energy consumption. Ultimately, the optimized conditions were as follows: extraction temperature 36°C, extraction time 52 min and liquid-to-solid ratio 5.78:1. Among these three parameters, temperature had the most significant effect on phorbol esters extraction efficiency followed by extraction time and liquid-to-solid ratio. Maximum content of phorbol esters obtained were 0.33 mg/g Jatropha curcas L. seed in the first step and 89.20 ± 2.96% of seed oil could be recovered by n-hexane in the second step. A sensitive ultra-performance liquid chromatography method was also established to determine the phorbol esters content within 5 min, with a limit of detection (LOD) of 0.04 μg/g. Since the concentrations of phorbol esters were all below the limit of detection, most of the virtually phorbol ester-free (PE-free) oil was produced to extend the Jatropha biodiesel production chain for household chemicals, cosmetic or jet fuel preparation. Meanwhile, the phorbol esters enriched fraction (PEEF, 71.9 ± 0.3 mg/g) obtained from the first step can be utilized as value-added by-products in pharmaceutical and agro-pharmaceutical fields.

Keywords

Jatropha

UPLC

Phorbol esters

By-products

PE-free oil

---

 Table 1

Table 1.

 Table 2

Table 2.

Fig. 1.

 Table 3

Table 3.

Fig. 2.

Fig. 3.

 Table 4

Table 4.

Fig. 4.

 Table 5

Table 5.

Fig. 5.

• ⁎ 
  Corresponding author at: College of life science, Sichuan University, No.24 South Section 1, Yihuan Road, Chengdu, PR China.

For further details log on website :
http://www.sciencedirect.com/science/article/pii/S0926669016308640