Toxic Compound, Anti-Nutritional Factors and Functional Properties of Protein Isolated from Detoxified Jatropha curcas Seed Cake

Jatropha curcas is a multipurpose tree, which has potential as an alternative source for biodiesel. All of its parts can also be used for human food, animal feed, fertilizer, fuel and traditional medicine. J. curcas seed cake is a low-value by-product obtained from biodiesel production. The seed cake, however, has a high amount of protein, with the presence of a main toxic compound: phorbol esters as well as anti-nutritional factors: trypsin inhibitors, phytic acid, lectin and saponin. The objective of this work was to detoxify J. curcas seed cake and study the toxin, anti-nutritional factors and also functional properties of the protein isolated from the detoxified seed cake. The yield of protein isolate was approximately 70.9%. The protein isolate was obtained without a detectable level of phorbol esters. The solubility of the protein isolate was maximal at pH 12.0 and minimal at pH 4.0. The water and oil binding capacities of the protein isolate were 1.76 g water/g protein and 1.07 mL oil/g protein, respectively. The foam capacity and stability, including emulsion activity and stability of protein isolate, had higher values in a range of basic pHs, while foam and emulsion stabilities decreased with increasing time. The results suggest that the detoxified J. curcas seed cake has potential to be exploited as a novel source of functional protein for food applications.     

Reactive extraction and in situ esterification of Jatropha curcas L. seeds for the production of biodiesel

Jatropha curcas L. has recently been hailed as the promising feedstock for biodiesel production as it does not compete with food sources. Conventional production of biodiesel from J. curcas L. seeds involve two main processing steps; extraction of oil and subsequent esterification/transesterification to fatty acid methyl esters (FAME). In this study, the feasibility of in situ extraction, esterification and transesterification of J. curcas L. seeds to biodiesel was investigated. It was found that the size of the seed and reaction period effect the yield of FAME and amount of oil extracted significantly. Using seed with size less than 0.355 mm and n-hexane as co-solvent with the following reaction conditions; reaction temperature of 60 °C, reaction period of 24 h, methanol to seed ratio of 7.5 ml/g and 15 wt% of H₂SO₄, the oil extraction efficiency and FAME yield can reached 91.2% and 99.8%, respectively. This single step of reactive extraction process therefore can be a potential route for biodiesel production that reduces processing steps and cost.     

Potential of <Emphasis Type="Italic">Jatropha curcas</Emphasis> as a Biofuel,Animal Feed and Health Products

Jatropha curcas is a multipurpose plant with numerous attributes. It can potentially become one of the world’s key energy crops. Its seed weighs 0.53–0.86 g and the seed kernel contains 22–27% protein and 57–63% lipid indicating good nutritional value. The seeds can produce crude vegetable oil that can be transformed into high quality biodiesel. Several methods for oil extraction have been developed. In all processes, about 75% of the weight of the seed remains as a press cake containing mainly carbohydrates, protein and residual oil and is a potential source of livestock feed. The highly toxic nature of whole as well as dehulled seed meal due to the presence of high levels of shells, toxic phorbol esters and other antinutrients prevents its use in animal diet. The genetic variation among accessions from different regions of the world and rich diversity among Mexican genotypes in terms of phorbol ester content and distinct molecular profiles indicates the potential for improvement of germplasm of Jatropha through breeding programs. The extracts of Jatropha display potent cytotoxic, antitumor, anti-inflammatory and antimicrobial activities. The possibilities on the exploitation potential of this plant through various applications have been explored.     

Dynamic Analysis of Phorbol Esters in the Manufacturing Process of Fatty Acid Methyl Esters from <Emphasis Type="Italic">Jatropha curcas</Emphasis> Seed Oil

Jatropha curcas seed oil, which is unsuitable as an edible oil but has received attention as a novel vegetable fat and oil resource, contains tumor-promoting phorbol esters. Currently, six types of derivatives of 12-deoxy-16-hydroxyphorbol (DHPEs) in J. curcas oil have been identified, and their toxicological safety for humans is being discussed. However, it is reported that most DHPEs disappear during the transesterification process. We investigated the dynamics of phorbol esters in the manufacturing process of fatty acid methyl esters from J. curcas seed oil. With the assumption that the precursor ion was the fragment ion (m/z = 311) from the frame unit of phorbol esters and their derivatives, we developed an LC–MS method for detecting the product ion (m/z = 165), which was obtained by cleavage of the fragment ion. The derivatives generated from the structural changes of the phorbol esters existed in fractions of glycerine–water in the manufacturing process; however, phorbol esters and their derivatives were not detected in the fatty acid methyl esters that were produced via a high-vacuum distillation process. Investigation into the dynamics of phorbol esters confirmed that the contents of phorbol esters, including DHPEs, in the fatty acid methyl esters were under detection limits.     

Removal and Degradation of Phorbol Esters during Pre-treatment and Transesterification of <Emphasis Type="Italic">Jatropha curcas</Emphasis> Oil

Phorbol esters present in Jatropha curcas oil are toxic when consumed and are co-carcinogens. These could be a potential constraint in the widespread acceptance of Jatropha oil as a source of biodiesel. Phorbol esters were quantified in the fractions obtained at different stages of oil pre-treatment and biodiesel production. During degumming some phorbol esters were removed in the acid gums and wash water. This implies that the use of these acid gums in animal feed is not possible and care should be taken when disposing the wash water into the environment. Silica treatment did not decrease the phorbol esters, while stripping/deodorization at 260 °C at 3 mbar pressure with 1% steam injection completely degraded phorbol esters. Phorbol esters were not detected in stripped oil, fatty acid distillate, transesterified oil (biodiesel) and glycerine. The presence of possibly toxic phorbol ester degradation products in these fractions could not be ruled out.     

Analysis of parameters and interaction between parameters of the microwave-assisted continuous transesterification process of Jatropha oil using response surface methodology

A simple continuous process was designed for the transesterification of Jatropha curcas (J. curcas) oil to alkyl esters using microwave-assisted method. The product with purity above 96.5% of alkyl ester is called the biodiesel fuel. Using response surface methodology, a series of experiments with three reaction factors at three levels were carried out to investigate the transesterification reaction in a microwave and conversion of alkyl ester from J. curcas oil with NaOH as the catalyst. The results showed that the ratio of methanol to oil, amount of catalyst and flow rate have significant effects on the transesterification and conversion of alkyl ester. Based on the response surface methodology using the selected operating conditions, the optimal ratio of methanol to oil, amount of catalyst and flow rate of transesterification process were 10.74, 1.26 wt% and 1.62 mL/min, respectively. The largest predicted and experimental conversions of alkyl esters (biodiesel) under the optimal conditions are 99.63% and 99.36%, respectively. Our findings confirmed the successful development of a two-step process for the transesterification reaction of Jatropha oil by microwave-assisted heating, which is effective and time-saving for alkyl ester production.     

Oxidation stability of blends of Jatropha biodiesel with diesel

Biodiesel, an ecofriendly and renewable fuel substitute for diesel has been receiving the attention of researchers around the world. Due to heavy import of edible oil, the production of biodiesel from edible oil resources in India is not advisable. Therefore it is necessary to explore non-edible seed oils, like Jatropha curcas (J. curcas) and Pongamia for biodiesel production. The oxidation stability of biodiesel from J. curcas oil (JCO) is very poor and therefore an idea is given to increase the oxidation stability of biodiesel by blending it with petro-diesel. J. curcas biodiesel (JCB), when blended with petro diesel leads to a composition having efficient and improved oxidation stability. The results have shown that blending of JCB with diesel with less than 20% (v/v) would not need any antioxidants but at the same time, need large storage space. Similarly, if the amount of diesel is decreased in the blend, it will require the addition of antioxidant but in lesser amount compared to pure JCB. For the purpose five antioxidants were used namely butylated hydroxytoluene (BHT), tert-butyl hydroquinone (TBHQ), butylated hydroxyanisole (BHA), propyl gallate (PG), and pyrogallol (PY). A B₃₀ blend (30% JCB in the blend of JCB and petro-diesel) has been tested for the same purpose. PY is found to be the best antioxidant among all five antioxidants used. The optimum amount of antioxidant (PY) for pure biodiesel tested for the present experiment is around 100 ppm while it is around 50 ppm for B₃₀ blend to maintain the international specification of oxidation stability.     

Quantification of Phorbol Esters in Jatropha curcas by HPLC‐UV and HPLC‐ToF‐MS with Standard Addition Method

Established analytic methods for the quantification of phorbol esters (PE), which are some toxic components in Jatropha curcas L., include HPLC with UV‐detection with the commercially available phorbol myristate acetate (PMA) as internal standard or HPLC coupled with MS detection with an external calibration, mostly also with PMA. The differences in the fatty acid side chains and connection to the base structure of PMA compared to PE leads to different UV absorption and MS ionization effects and cause problems for exact quantitative measurements. In this paper, a method is presented which combines both detection types and shows differences between both results. For this purpose, an extraction routine is performed on a PE‐containing seed oil to get a PE standard in high purity, which was used for a standard addition method on two real J. curcas oil samples, derived from Ghana and Mexico. Furthermore, a detection window of ±10 ppm for the high accurate ToF‐MS detection is set to eliminate isobaric interferences from co‐eluting material. Method evaluation of inter‐ and intra‐day variance as well as the recovery rate are performed and determined. With this method a limit of detection of 62 ng mL^?1 (UV) and 11 ng mL^?1 (MS) can be achieved. Practical Applications: Due to the good biological and technical properties of Jatropha curcas L., its seed oil seems perfect for the application as biodiesel feedstock. The toxicity on the other hand could cause problems when converting side products from the oil production to products of higher value. With the here described method an accurate and precise analysis procedure for the quantification of the toxic compounds namely, phorbol esters, could be applied for toxicity studies or routine checks in industry which is converting plant material from J. curcas, so that no toxic material is used for example as animal feed. In this paper, an exact and robust analysis method is described for the quantification of phorbol esters (PE) in Jatropha curcas L. seed oil. This method procedure includes the extraction of PE in methanol, chromatographic separation on a reverse phase C18 HPLC column and the quantification by standard addition method. For the standard addition method a highly pure PE standard is used, which is extracted and purified by semi preparative HPLC right before the measurements. The used detector for identification and quantification is UV set at 280 nm and ESI‐ToF‐MS with a ±10 ppm mass difference of the deprotonated and formate adduct pseudo molecular ion of PE.

     

Jatropha curcas,a promising crop for the generation of biodiesel and value‐added coproducts

The review highlights the specific features of the Jatropha curcas plant and its potential for the production of biofuel, protein concentrates as livestock feed and value‐added products that could enhance the economic viability of Jatropha seed oil‐based biodiesel production. The roles of the plant in carbon capture, enhancing socio‐economic conditions, food production in the tropical regions, and influencing micro‐climate, vegetation and soil quality are discussed. The paper also gives a comparative account of the toxic and non‐toxic genotypes of J. curcas from the point of view of their physical and chemical properties and their potential for biodiesel and livestock feed production. Future areas of research are also presented.     

Chemical and functional characterization of major protein fractions extracted from nontoxic Jatropha curcas byproduct meals

Jatropha curcas seeds are a suitable source of oil for biofuel, among other use. A protein-rich meal is obtained after oilseed extraction. The goals of this study were to determine the physicochemical and functional properties of a nontoxic genotype of J. curcas defatted meal (JCDM) and the seed storage protein fractions to identify future applications. Both glutelin and globulin were the predominant protein fractions obtained from JCDM (42.03 and 20.17 g/100 g of protein, respectively). Leucine, phenylalanine + tyrosine, and histidine content of JCDM and protein fractions met the Food and Agriculture Organization/World Health Organization recommendation for children. The protein solubility (PS) profiles showed minimum values (5.3%–59.7%) at pH 5–6 and maximum at pH 2 (79.7%–81.6%) and above pH 10 (84.6%–89.8%). These findings suggest that JCDM proteins could be used in the formulation of juice or protein-based beverages. All the proteins showed the highest values for foam expansion (231%–285%) at pH 9. JCDM and the albumin fraction formed highly stable foams at pH 9, while the globulin and glutelin foams were stable at pH 3 and 2, respectively. Protein with stable foams, like those from jatropha are suitable for application in ice cream, mousse, among others. The emulsion activity index had similar behavior as foam expansion, but did not follow a specific trend. Thus, the proteins are suitable for use in salad dressing, sausages, comminuted meats, and mayonnaise. Taken together, JCDM protein and its soluble protein fractions have strong promise as alternative proteins for food structuring.     

Nutritive value of defatted seed cake ofCleome viscosa

Defatted seed cake ofCleome viscosa was analysed for protein, amino acids, vitamins and minerals. It was found to be a fairly good source of protein and other nutrients. The most limiting amino acid of the protein in the defatted seed cake was tryptophan. Like otherCapparidaceous plants, seeds ofCleome viscosa contained thioglucosinolates. The concentration of which in defatted seed cake before and after detoxification was 3 and 0.12 mg per 100 g. Except for the loss of B-complex vitamins, on detoxification the nutrient composition of the defatted cake remained unaltered. Rats fed diets based on defatted cake containing the toxic compounds lost weight, but those fed detoxified cake showed improved growth. However, the relative protein value (RPV) of the processed cake was poor and suggested the presence of other antinutritional factors.     

Optimization of biodiesel production from edible and non-edible vegetable oils

The non-edible vegetable oils such as Jatropha curcas and Pongamia glabra (karanja) and edible oils such as corn and canola were found to be good viable sources for producing biodiesel. Biodiesel production from different edible and non-edible vegetable oils was compared in order to optimize the biodiesel production process. The analysis of different oil properties, fuel properties and process parameter optimization of non-edible and edible vegetable oils were investigated in detail. A two-step and single-step transesterification process was used to produce biodiesel from high free fatty acid (FFA) non-edible oils and edible vegetable oils, respectively. This process gives yields of about 90-95% for J. curcas, 80-85% for P. glabra, 80-95% for canola, and 85-96% for corn using potassium hydroxide (KOH) as a catalyst. The fuel properties of biodiesel produced were compared with ASTM standards for biodiesel.     

Extraction,Composition and Functional Properties of Pennycress (Thlaspi arvense L.) Press Cake Protein

This study compared two methods for extracting the protein in pennycress (Thlaspi arvense L.) press cake and determined the composition and functional properties of the protein products. Proteins in pennycress press cake were extracted by using the conventional alkali‐solubilization–acid‐precipitation (AP) method or saline‐based (SE) procedure (0.1 M NaCl at 50 °C). The extraction method has a major influence on the purity and functional properties of press cake protein products. AP had a lower protein yield (23 %) but much higher purity (90 % crude protein) compared with SE (45 % yield, 67 % crude protein). AP protein isolate had high foam capacity (120 ml), high foam stability (96 % foam volume retention) and high emulsion stability (24–35 min), and it was resistant to heat denaturation (3 % loss of solubility at pH 2 and pH 10). On the other hand, SE protein concentrate showed remarkably high solubility (>76 %) between pH 2 and 10 and exceptional emulsifying activity (226–412 m²/g protein), but was more susceptible to heat denaturation at pH 7 and pH 10 (65–78 % loss of solubility). These results strongly demonstrate that higher purity pennycress press cake protein can be produced by either saline extraction or acid precipitation and have functional properties that are desirable for non‐food uses.     

Removal of Phorbol Ester from Jatropha Seedcake Using Ozonation and Solar Irradiation

Jatropha curcas is a well-known source of non-edible vegetable oil that is being promoted as an energy source and high quality feedstock in biodiesel production, especially in developing countries. The potential that the resulting seedcake by-product from jatropha oil extraction (?70% by volume) could also be used as a component in animal feed raises the prospect that a commercially viable jatropha-based industry could be developed. To date, however, the use of jatropha seedcake in livestock feed formulation has been constrained by the presence of phorbol esters (PE), which are known promutagenic and toxic compounds, and by the inability to eliminate PE by cost-effective means. Using seedcake by-product collected from a commercial facility in West Africa that processes jatropha biodiesel, this study demonstrates cost-effective measures of eliminating PE from jatropha seedcake using a combination of solar irradiation and ozonation.     

Process optimization for biodiesel production from Jatropha, Karanja and Polanga oils

Petroleum sourced fuels is now widely known as non-renewable due to fossil fuel depletion and environmental degradation. Renewable, carbon neutral, transport fuels are necessary for environmental and economic sustainability. Biodiesel derived from oil crops is a potential renewable and carbon neutral alternative to petroleum fuels. Chemically, biodiesel is monoalkyl esters of long chain fatty acids derived from renewable feed stock like vegetable oils and animal fats. It is produced by transesterification in which, oil or fat is reacted with a monohydric alcohol in presence of a catalyst. The process of transesterification is affected by the mode of reaction condition, molar ratio of alcohol to oil, type of alcohol, type and amount of catalysts, reaction time and temperature and purity of reactants. In the present paper various methods of preparation of biodiesel from non-edible filtered Jatropha (Jatropha curcas), Karanja (Pongamia pinnata) and Polanga (Calophyllum inophyllum) oil have been described. Mono esters (biodiesel) produced and blended with diesel were evaluated. The technical tools and processes for monitoring the transesterification reactions like TLC, GC and HPLC have also been used.     

Process optimization design for jatropha-based biodiesel production using response surface methodology

Biodiesel of non food vegetal oil origin is gaining attention as a replacement for current fossil fuels as its non-food chain interfering manufacturing processes shall prevent food source competition which is expected to happen with current biodiesel production processes. As a result, non edible Jatropha curcas plant oil is claimed to be a highly potential feedstock for non-food origin biodiesel. CaO–MgO mixed oxide catalyst was employed in transesterification of non-edible J. curcas plant oil in biodiesel production. Response surface methodology (RSM) in conjunction with the central composite design (CCD) was employed to statistically evaluate and optimize the biodiesel production process. It was found that the production of biodiesel achieved an optimum level of 93.55% biodiesel yield at the following reaction conditions: 1) Methanol/oil molar ratio: 38.67, 2) Reaction time: 3.44 h, 3) Catalyst amount: 3.70 wt.%, and 4) Reaction temperature: 115.87 °C. In economic point of view, transesterification of J. curcas plant oil using CaO–MgO mixed oxide catalyst requires less energy which contributed to high production cost in biodiesel production. The incredibly high biodiesel yield of 93.55% was proved to be the synergetic effect of basicity between the active components of CaO–MgO shown in the physicochemical analysis.     

Extraction,transesterification and process control in biodiesel production from Jatropha curcas

Biodiesel has gained worldwide popularity as an alternative energy source due to its renewable, non‐toxic, biodegradable and non‐flammable properties. It also has low emission profiles and is environmentally beneficial. Biodiesel can be used either in pure form or blended with conventional petrodiesel in automobiles without any major engine modifications. Various non‐edible and edible oils can be used for the preparation of biodiesel. With no competition with food uses, the use of non‐edible oils as alternative source for engine fuel will be important. Among the non‐edible oils, such as Pongamia, Argemone and Castor, Jatropha curcas has tremendous potential for biodiesel production. J. curcas, growing mainly in tropical and sub‐tropical climates across the developing world, is a multipurpose species with many attributes and considerable potentials. In this article, we review the oil extraction and characterization, the role of different catalysts on transesterification, the current state‐of‐the‐art in biodiesel production, the process control and future potential improvement of biodiesel production from J. curcas.     

Biodiesel preparation,optimization, and fuel properties from non-edible feedstock,Datura stramonium L.

This is a study on the feasibility of biodiesel preparation from a new and promising non-edible feedstock, Datura stramonium L. oil (DSO). First, important physical–chemical properties, such as oil content of seed (21.4 wt%), acid value (7.93 mg KOH/g) and fatty acid composition of expressed oil, were determined. Second, under the optimal two-step catalyzed reaction conditions, the maximum fatty acid methyl ester (FAME) yield (87%) and FAME content of more than 98 wt% were obtained. Furthermore, the fuel properties of DSO biodiesel were determined and evaluated. Compared with Jatrpha curcas L. (JC) and beef tallow (BT) biodiesel, DSO biodiesel possessed the best kinematic viscosity (4.33 mm²/s) and cold filter plug point (?5 °C). Based on the results, D. stramonium L. was identified as a promising species for biodiesel feedstock.     

Combustion analysis of Jatropha, Karanja and Polanga based biodiesel as fuel in a diesel engine

Non-edible filtered Jatropha (Jatropha curcas), Karanja (Pongamia pinnata) and Polanga (Calophyllum inophyllum) oil based mono esters (biodiesel) produced and blended with diesel were tested for their use as substitute fuels of diesel engines. The major objective of the present investigations was to experimentally access the practical applications of biodiesel in a single cylinder diesel engine used in generating sets and the agricultural applications in India. Diesel; neat biodiesel from Jatropha, Karanja and Polanga; and their blends (20 and 50 by v%) were used for conducting combustion tests at varying loads (0, 50 and 100%). The engine combustion parameters such as peak pressure, time of occurrence of peak pressure, heat release rate and ignition delay were computed. Combustion analysis revealed that neat Polanga biodiesel that results in maximum peak cylinder pressure was the optimum fuel blend as far as the peak cylinder pressure was concerned. The ignition delays were consistently shorter for neat Jatropha biodiesel, varying between 5.9^° and 4.2^° crank angles lower than diesel with the difference increasing with the load. Similarly, ignition delays were shorter for neat Karanja and Polanga biodiesel when compared with diesel.     

Quality of Biodiesel Prepared from Phorbol Ester Extracted <Emphasis Type="Italic">Jatropha curcas</Emphasis> Oil

Jatropha curcas seeds are rich in oil (28–32%), which can be converted to high quality biodiesel. The oil is non-edible due to the presence of toxic compounds, namely, phorbol esters (PEs). PEs have a number of agricultural/medicinal/pharmaceutical applications and hence their recovery generates a value added co-product towards the biodiesel production chain. This study aims to assess the effects of PE extraction on quality of both the residual oil and the biodiesel production from it. Two Approaches (1, use of an Ultra-turrax; and 2, use of a magnetic stirrer) were used with an effective treatment time of 2 and 5 min, resulting in 80 and 78% extraction of PEs, respectively. The phosphorus content was reduced by 70.2 and 75.8%, free fatty acids by 55.3 and 55.6%, and the fatty acid composition did not change in the residual oils. The peroxide value increased from 2.69 (untreated oil) to 3.01 and 3.49 mequiv O₂/kg in the residual oils following Approach 1 and Approach 2, respectively. The biodiesel prepared from both residual oils met European (EN 14214:2008) and American biodiesel standard (ASTM D6751-09) specifications. Oxidative stability indices for both the biodiesels were well within the permitted limit. It is concluded that PEs could be isolated in active forms for various applications by either of the two methods with a high yield and the residual oil can be processed to produce high quality biodiesel.