Physicochemical properties of stillingia oil: Feasibility for biodiesel production by enzyme transesterification

The physicochemical properties, fatty acids profile and triglyceride compositions of the stillingia oil were analyzed. The stillingia oil was found to contain 98.79% neutral lipids, 0.22% phospholipids and 0.99% glycolipids, which exhibited varying contents of fatty acids. The major triglyceride was double linoleic acid linolenic acid triglyceride, which accounted for approximately 79.49% of the total triglycerides. Preparation of biodiesel from stillingia oil was investigated by enzyme transesterification with methanol as the acyl acceptor. The results showed that lipase type (Novozym 435, Lipozyme TLIM and Lipozyme RMIM), reaction systems (in solvent-free and tert-butanol system) and operational parameters (lipase loading, reaction time, temperature, and molar ratio of alcohol to oil) influenced the biodiesel yield. Fuel properties of biodiesel from stillingia oil were evaluated and all were in acceptable range for use as biodiesel in diesel engines, and had remarkable flash point and satisfactory cold flow properties. It was concluded that stillingia oil was an alternative potential feedstock oil for biodiesel production.     

Synthesis of Jatropha curcas oil-based biodiesel in a pulsed loop reactor

Jatropha curcas oil (JCO) has a high content of free fatty acids and has been used extensively as a feedstock in biodiesel production. In the present study, the transesterification reaction of JCO to Jatropha curcas methyl ester (biodiesel) was performed in a continuous pulsed loop reactor under atmospheric conditions. The JCO was pre-treated prior to the reaction to reduce the free fatty acid content to below 1% (w/w). The operating parameters of the loop reactor were optimised based on the conversion of the JCO to Jatropha curcas biodiesel and included reaction temperature, molar ratio of oil to MeOH, reaction time and oscillation frequency. The findings show that the highest reaction conversion of 99.7% (w/w) was achieved using KOH catalyst and 98.8% conversion was obtained using NaOCH₃ catalyst. The optimal operating conditions were a molar ratio of 6:1, an oscillation frequency of 6 Hz, temperature of 60 °C, feedstock FFA content of 0.5% (w/w) and only 10 min of reaction time. As a commercial commodity, the physical properties of biodiesel were analysed, and they compared well with the characteristics of fossil-based diesel fuel.     

Preparation of biodiesel from Idesia polycarpa var. vestita fruit oil

The feasibility of producing biodiesel from Idesia polycarpa var. vestita fruit oil was studied. A methyl ester biodiesel was prepared from refined I. polycarpa fruit oil using methanol and potassium hydroxide (KOH) in an alkali-catalyzed transesterification process. The experimental variables investigated in this study were catalyst concentration (0.5–2.0 wt.% of oil), methanol/oil molar ratio (4.5:1 to 6.5:1), temperature (20–60 °C) and reaction time (20–60 min). A maximum yield of over 99% of methyl esters in I. polycarpa fruit oil biodiesel was achieved using a 6:1 molar ratio of methanol to oil, 1.0% KOH (% oil) and reaction time for 40 min at 30 °C. The properties of I. polycarpa fruit oil methyl esters produced under optimum conditions were also analyzed for specifications for biodiesel as fuel in diesel engines according to China Biofuel Systems Standards. The fuel properties of the I. polycarpa fruit oil biodiesel obtained are similar to the No. 0 light diesel fuel and most of the parameters comply with the limits established by specifications for biodiesel.     

Variation in oil content and fatty acid profile of Calophyllum inophyllum L. with fruit maturity and its implications on resultant biodiesel quality

Variation in oil content and fatty acid profile (FAP) of Calophyllum inophyllum; a potential biodiesel feedstock species were studied at different maturity stages and biodiesel quality parameters were estimated based on the FAP. A steady increase in oil content was observed with maturity. Variation in palmitic (16:0) and linoleic (18:2) acids followed exactly opposite trends where palmitic acid content has decreased and linoleic acid content has increased 77 days after anthesis. Oleic acid (18:1) content has shown a steady increase. Stearic acid (18:0) content remained steady up to 68 days after anthesis and then felt slightly in 77 days after anthesis. Linoleic and eicosanoic acids were found to exist in low concentrations demonstrated very little compositional variation with fruit maturity. Estimated biodiesel parameters of all maturity stages were found to comply with industrial standards. Even though 48 days after anthesis had the most ideal FAP for biodiesel production, ∼77 days after anthesis is preferred point to harvest due to higher oil content.     

A Saponification Method for Chlorophyll Removal from Microalgae Biomass as Oil Feedstock

Microalgae oil is an optimal feedstock for nutraceutical, pharmaceutical and biodiesel production, but its high levels of chlorophyll limit its large-scale application. To date, few effective approaches have been developed to remove chlorophyll from microalgae oil. The main purpose of this study was to present a preprocessing method of algae oil feedstock (Scenedesmus) to remove chlorophyll by saponification. The results showed that 96% of chlorophyll in biomass was removed. High quality orange transparent oil could be extracted from the chlorophyll reduced biomass. Specifically, the proportion of neutral lipids and saturation levels of fatty acids increased, and the pigments composition became carotenoids-based. The critical parameters of chlorophyll reduced biodiesel conformed to the standards of the USA, China and EU. Sodium copper chlorophyllin could be prepared from the bleaching effluent. The results presented herein offer a useful pathway to improve the quality of microalgae oil and reduce the cost of microalgae biodiesel.     

The cellular structure of cork from Quercus cerris var. cerris bark in a materials’ perspective

Cork in the outer bark of trees is among the valuable raw materials of biological origin due to properties that result mainly from its cellular structure. Large scale commercial utilization of cork has been only achieved with cork from Quercus suber. Another oak species, Quercus cerris, also contains substantial, albeit not continuous, regions of cork that are clearly visible to the naked eye but are so far considered as a waste material.Bark samples of Q. cerris var. cerris trees were collected from the And?r?n province, Turkey. Cork portions were separated and their cellular structure was investigated with optical and electron scanning microscopy observations. The results were compared with Q. suber cork.Q. cerris cork has the typical features of cork tissues with a regular and radially aligned structure of suberized cells without intercellular voids, showing a ring structure and a distinction of earlycork and latecork cells. Solid volume fraction was estimated at 25% (22% in earlycork, 36% in latecork).In Q. cerris cork cells are smaller, cell wall thickness and solid volume fraction are higher, and the tissue is less homogeneous with a higher content of lignified inclusions than in Q. suber cork. These factors will negatively influence quality in regard to density and mechanical properties associated to elasticity. However, this does not impair its use for production of granulates and agglomerates, e.g. for insulation and energy absorption. Separation of the cork fraction from the bark is a step required before further processing and use.     

Tocochromanol content and composition in Jatropha curcas seeds

Physic nut (Jatropha curcas L.) is a promising seed oil source for biodiesel production. Natural antioxidants play a major role in maintaining oxidative stability of oils and they also have important food and industrial applications. Among them, tocochromanols are the most abundant in seeds. The objective of this research was to evaluate the variation for tocochromanol content and profile in a germplasm collection of 52 accessions of J. curcas. Seeds collected in two different periods, August and November of 2009, were analysed for tocochromanol content. Additionally, the dynamics of tocochromanol accumulation in developing seeds was studied. Total seed tocochromanol content averaged 307.2 mg kg⁻¹ in August and 303.7 mg kg⁻¹ in November, whereas total oil tocochromanol content averaged 507.4 mg kg⁻¹ in August and 500.8 mg kg⁻¹ in November. The tocochromanol fraction was made up of 15.4% gamma-tocopherol, 83.8% gamma-tocotrienol, and 0.8% delta-tocotrienol in August and 18.0% gamma-tocopherol, 80.4% gamma-tocotrienol, and 1.6% delta-tocotrienol in November. Genotype × environment effects were identified for tocochromanol content but not for the proportion of major tocochromanol homologues, which showed a high positive correlation between both environments. Developing seeds contained primarily alpha-tocopherol and gamma-tocopherol at early stages of development, with gamma-tocotrienol and delta-tocotrienol being practically undetectable. Gamma-tocotrienol content remained practically undetectable till 66 DAP and then increased pronouncedly to final levels of 177.1 mg kg⁻¹ (74.8% of the total tocochromanol content). The powerful antioxidant and health-promoting properties of gamma-tocotrienol encourages further studies on selection for the tocopherol/tocotrienol ratio in Jatropha and on the potential of tocochromanols as high added-value products derived from Jatropha seed oil production.     

Studies on the utilization of Hura crepitans L. seed oil in the preparation of alkyd resins

The utilization of Hura crepitans seed oil in the formulation of alkyd resins was investigated using a two-stage alcoholysis-polyesterification method. The percentage yield of the oil was 36.4%; and the physicochemical characterization revealed that the seed oil is an unsaturated semi-drying oil. The fatty acid profile of the oil showed that it contains linoleic acid (81.6%) as the most abundant fatty acid, and two other fatty acids: palmitic acid (16.92%) and stearic acid (1.76%). Short (I), medium (II) and long (III) oil alkyds were synthesized using the oil, glycerol and phthalic anhydride in different ratios. Properties of the three prepared samples of H. crepitans seed oil alkyds having oil content of 30% (I), 50% (II), and 65% (III) were evaluated. The alkyd resins synthesized compared favourably with the commercially available alkyd resin. The presence of unsaturation in the oil was confirmed by infra-red peak at 2930 cm⁻¹ attributed to CC stretch. The infra-red peaks of the sample also compared well with that of the commercial sample indicating that H. crepitans seed oil has been successfully converted to alkyd resin. Evaluation of prepared alkyds by determination of acid values, solubility in butanol and toluene, resistance of dry film to acid, alkali and water, and drying time revealed that H. crepitans seed oil is a potential raw material for the coating industry.     

Synthesis and characterization of hazelnut oil-based biodiesel

The demand for diesel fuel far exceeds the current and future biodiesel production capabilities of the vegetable oil and animal fat industries. New oilseed crops that do not compete with traditional food crop are needed to meet existing energy demands. Hybrid hazelnut oil is just such an attractive raw material for production of biodiesel. Hazelnut oil was extracted from hybrid hazelnuts and the crude oil was refined. Hazelnut oil-based biodiesel was prepared via the transesterification of the refined hazelnut oil with excess methanol using an alkaline catalyst. The effects of reaction temperature, time and catalyst concentration on the yield of diesel were examined, and selected physical and chemical properties of the biodiesel were evaluated. The biodiesel yield increased with increasing temperature from 25 to 65 °C and with increasing catalyst concentration from 0.1 to 0.7 wt%. The increase in yield with reaction time was nonlinear and characterized by an initial faster rate, followed by a slow rate. Hazelnut oil-based biodiesel had an average viscosity of 8.82 cP at 25 °C, which was slightly higher than that of the commercial soy-based diesel (7.92 cP at 25 °C). An approximate 12 °C higher onset oxidative temperature and a 10 °C lower cloud point of hazelnut oil biodiesel than those of its commercial soy counterpart indicated a better oxidative stability and flowability at low temperature. The average heat of combustion of hazelnut oil biodiesel was 40.23 kJ/g, and accounted for approximately 88% of energy content of diesel fuel. The fatty acid composition of hazelnut oil-based biodiesel was the same as the nature oil.     

Industrial utilization of Triumfetta pilosa,Roth seed oil: A moderate source of oil and cyclopropenoid fatty acids

Triumfetta pilosa contain malvalic acid (2.4%) and sterculic acid (6.6%) along with the other normal fatty acids like palmitic (16.7%), stearic (10.8%), oleic (20.1%) and linoleic (43.4%). The cyclopropenoid (malvalic and sterculic) and other normal fatty acids have been determined by FTIR, ¹H NMR, gas liquid chromatographic-techniques and chemical degradations.     

棕榈油生物柴油加工技术研究进展

棕榈油是世界上最经济的植物油,与其他油料作物相比,油棕果及油的产量均最高,棕榈油作为生物质能源的原料越来越被重视,成为生产生物柴油最有竞争力的原料.目前.世界各国对棕榈油生物柴油的高效加工技术均展开了广泛的研究.本文介绍了国内外棕榈油生物柴油的加工技术,包括化学法、酶法、多相固体催化法及其他一些方法.     

Variability assessment in Pongamia pinnata (L.) Pierre germplasm for biodiesel traits

Wide variability in oil content was observed in 75 germplasm accessions of Pongamia pinnata (L.) Pierre collected from Telengana region of Andhra Pradesh, India. Out of these, fatty acid profiles of 21 accessions with varying seed oil content were examined. Large variation was observed in stearic, oleic and linoleic fatty acid composition i.e. 1.83–11.50%, 46.66–65.35% and 12.02–32.58% respectively while less variation i.e. 9.25–12.87% was found with palmitic acid content. Saponification number (SN), iodine value (IV) and cetane number (CN) of fatty acid methyl esters of oils varied from 183.3 to 200.91, 74.78 to 100.98 and 50.85 to 59.11 respectively. Fatty acid composition, IV and CN were used to predict the quality of fatty acid methyl esters of oil for use as biodiesel. Fatty acid methyl esters of oils of P. pinnata accessions DORPP 49, 72 and 83 were found most suitable (CN more than 56.6) for use as biodiesel and they meet the major specification of biodiesel standards of USA, Germany and European Standard Organization. The range of variability found for various biodiesel standards in accessions of P. pinnata can be utilized for the establishment of plantations of promising genotypes through clonal means for increased productivity.     

Rice bran, a potential source of biodiesel production in Indonesia

Biodiesel is a biodegradable, renewable, non-toxic and environmentally friendly alternative fuel. The cost of raw materials comprises 60-88% of the production cost in commercial biodiesel (fatty acid methyl esters, FAMEs) production. Therefore, the use of low-cost raw material as a substrate and an in situ process for biodiesel production are being preferred. In this case, rice bran, which contains 13.5% oil, was an interesting substrate. In situ esterification of high-acidity rice bran with methanol and sulfuric acid catalyst was investigated. The individual and interaction effects of methanol to rice bran ratio, sulfuric acid catalyst concentration and reaction time on purity and recovery of biodiesel were discussed. Our results suggest that under the following operation conditions: methanol to rice bran ratio of 5 mL/g, sulfuric acid concentration in methanol of 1.5 vol.%, and reaction time of 60 min, an in situ esterification operated on rice bran could yield FAMEs with a high purity and recovery. By applying an in situ esterification with n-hexane/water extractions, Indonesia will be succesfull in obtaining biodiesel from rice bran up to 96,000 ton per year.     

Breeding prospects of Lunaria annua L.

Lunaria annua is a biennial cruciferous oil seed crop. The seeds contain 30–35% oil, which consists of 67% long chain fatty acids (44% erucic acid, C22:1, and 23% nervonic acid, C24:1). The oil is suitable as lubricant. In addition, recent developments indicate that nervonic acid may be used as raw material for the production of a medicine against multiple sclerosis. The biennial character of Lunaria is a main constraint for an economically feasible production of Lunaria oil. The crop has to be sown early in the summer to achieve vigorous plant development required for vernalization during the winter. It would be a great advance when Lunaria could be sown later in the summer after an early harvested crop. From 1993, breeding research in Lunaria has been performed at CPRO-DLO, Wageningen, The Netherlands. A collection of 76 accessions was maintained and evaluated for agronomic performance. In 1995, a selection of 24 accessions were sown at four sowing dates, from end June until end of August and in 1996, 12 promising accessions were sown again at 15 and 30 July. Three accessions showed suitability for delayed sowing until beginning of August. Delay in sowing time caused also delay of flowering and seed ripening. Seed yield amounted to 1200 kg/ha in 1996 and 1700 kg/ha in 1997. Seed oil content varied from 30–38%. Severe infection of Albugo candida and Alternaria occurred and might have reduced seed yield in both years. Most accessions sustained severe winter frost of−17°C very well. It is concluded that within the evaluated gene pool promising variation is available to select for ability for late sowing, to improve the disease resistance and to increase seed yield and seed oil content.     

Seed characteristics of okra and relatedAbelmoschus species

Variation in 10 seed characteristics was studied in the species groups, common okra (Abelmoschus esculentus), an African species with edible pods, and in related species. The groups differed significantly in 9 of the 10 characteristics. A relatively large hull fraction limited protein and oil contents. Seeds of common okra contain more oil, less protein, and less cyclopropenoid fatty acids than those of African okras, and have a larger kernel fraction, a higher percentage of large seeds, heavier seeds, more pubescence, and a lighter color. Protein and oil contents were inversely correlated. Gossypol or gossypol-like compounds were lower in common okras than in related species. Varieties particularly low in toxic substances were identified.     

Antifungal and antiaflatoxigenic efficacy of Caesulia axillaris Roxb. essential oil against fungi deteriorating some herbal raw materials, and its antioxidant activity

The study deals with evaluation of antifungal and antiaflatoxigenic Caesulia axillaris Roxb. essential oil (EO) against herbal raw materials deteriorating fungi and its free radical scavenging activity. During mycoflora analysis these herbal raw materials were found to be severely contaminated by different fungi and aflatoxins. A total of nine different fungal species were isolated from three herbal raw materials. Aspergillus flavus LHPtc was recorded as the highest aflatoxin B1 producing strain. EOs of some plants were tested for their fungitoxicity against the toxigenic strain A. flavus LHPtc, and C. axillaris EO was found as potent fungitoxicant. C. axillaris EO was chemically characterized through GC-MS analysis which depicted the presence of 18 compounds, dl-limonene and Euasarone being the major components. The EO exhibited broad spectrum of fungitoxicity against fungi causing postharvest deterioration of herbal raw materials. At 1.0 μl ml⁻¹ the oil showed complete inhibition of fungal growth and aflatoxin B₁ production was inhibited at 0.8 μl ml⁻¹. Free radical scavenging activity of the oil was also recorded by 2,2-diphenyl-1-picrylhydrazyl assay, and its IC₅₀ value was found 18 μl ml⁻¹. The safety limit of the EO was determined in terms of LD₅₀ on mice, which was 9166.6 μl kg⁻¹, suggesting its non mammalian toxicity. The EO of C. axillaris may be recommended as a plant based preservative in enhancement of shelf life of herbal raw materials by preventing their lipid peroxidation as well as biodeterioration due to fungal and aflatoxin contamination.     

Microscopy techniques and image analysis for evaluation of some chemical and physical properties and morphological features for seeds of the castor oil plant (Ricinus communis)

Ricinus communis seed is a source of protein and oil with a high potential to use as animal's feedstock and biodiesel production. However, the oil yield and the extraction efficiency depend on the process conditions applied, as well as on the physical, chemical and structural properties of the seed, which have not been fully investigated. Hence, the objective of this study was to evaluate some chemical and physical properties of R. communis seed as well as to describe and quantify the macro and microstructure of this raw material by microscopy techniques and image analysis. Chemical analysis confirmed the seeds’ high contents of protein (28.48 ± 0.25%) and fat (51 ± 0.31%). On the other hand, the values of geometric mean diameter (8.95 ± 0.05 mm), bulk density (538 ± 11 kg/m³), and true density (1458 ± 27 kg/m³), among others, were higher than the ones reported about similar oils seeds. Microstructural studies showed that the endosperm cells presented an ovoid shape, as obtained from the aspect ratio results (AR = 1.28 ± 0.17), and a cell density of 570 ± 10 cell/mm², resulting in a porous structure, while the embryo cells had a cell density of 4903 ± 2 cell/mm², and an AR of 2.41 ± 0.48, related to a more compact structure (rectangular form) in this part of the seed. Regarding to lipids bodies (lb), they were only visible in the endosperm cells, showing a circular shape (AR = 1.16 ± 0.1), and a mean cell density of 9.57 ± 2.40 lipid bodies/μm², associated to protein as observed by the mineral presence (K, P, Mg and S) as determined by the energy dispersive X-ray analysis. Microscopy techniques and images analysis were efficient tools for the characterization of macro and microstructure of seeds and the data obtained integrate numerical information that could be useful for thermal and mechanical processing of R. communis seed, as well as for the design process equipment.     

Optimization of harvest regime and post-harvest handling in geranium production to maximize essential oil yield in Rwanda

In Rwanda, the production of geranium (Pelargonium sp.) essential oil is becoming an important commercial crop for income generation. The understanding of postharvest handling of the crop prior to distillation is a key strategy to maximize oil yields. Two experiments were conducted in commercial fields of rose geranium, Pelargonium graveolens, in Kiyombe (Rwanda) to investigate the effects of (i) the length of dry-down or partial wilt and (ii) the time of day on the quantity and quality of essential oil yield and composition. In the first study, the plant material was harvested at 12:00 noon, and while drying also under the same shade conditions the material was sub-sampled immediately and again at 3 h intervals up through 46-h after harvesting. In the second study, the geranium plants were manually harvested at 10:00 AM, 12:00 noon, 2:00 PM, and 4:00 PM and dried under shade for 17 h prior to steam distillation. The geranium plants harvested in the early afternoon (2:00 PM) had the highest essential oil concentration (0.22%). The chemical profile of the essential oil showed that Kiyombe geranium oil exhibited a suitable chemical composition (citronellol 26.4%, linalool 2.3% and geraniol 13.9%), acceptable for international markets.     

Methyl ester of Sal oil (Shorea robusta) as a substitute to diesel fuel—A study on its preparation, performance and emissions in direct injection diesel engine

Many research reported vegetable oil as a potential substitute for diesel engines with its ester form known as biodiesel. The biodiesel can be prepared by different process using vegetable oil and alcohol. The common process used for biodiesel preparation is known as transesterification. This paper presents the transesterification of Sal oil (Shorea robusta) into Sal oil methyl ester (SOME) and its performance in direct injection diesel engine. Several process parameters such as catalyst quantity, molar ratio of alcohol, reaction temperature and reaction time were studied and the optimized process conditions are amount of catalyst (NaOH) - 0.25 wt%, alcohol (methanol) - 150% excess, reaction temperature - 65 °C and reaction time - 1.5 h. The studies with SOME as fuel in the direct injection diesel engine shows that the exhaust emissions such as CO, HC and NO_x are reduced by 25%, 45% and 12%, respectively compared to diesel without significant difference in thermal efficiency. Based on this study it is concluded that the SOME can be used as fuel without any modifications in the engine and hence this biodiesel can be a potential substitute to standard diesel fuel.     

Value added waste of Jatropha curcas residue: Optimization of protease production in solid state fermentation by Taguchi DOE methodology

The oil extraction of Jatropha curcas created the large amount of the by-product from its seeds. An application of solid-state fermentation (SSF) was considered to be of value to these raw materials. This study investigated the potential of a utilization of deoiled J. curcas seed cake as substrate for protease productions by Aspergillus oryzae. While various parameters for SSF was conventionally individually optimized, five parameters were simultaneously examined based on Taguchi method. The effect of three different levels of five factors, including moisture content of substrate, inoculums size, incubation temperature, type of porous substrate and incubation time were examined. The optimum conditions for the protease production by A. oryzae obtained from this experiment were 45% moisture content of substrate, 10% inoculums size, 30 °C incubation temperature, deoiled J. curcas seed cake mixed with cassava bagasse ratio 4:1 as porous substrate at 84 h of incubation time. By adjusting the conditions to these optimum levels, the protease production increased up to 4.6 times as many as the protease yield from the non-optimizing experiment. The use of statistical approach, Taguchi method, provided a satisfactory outcome in defining the optimum conditions for protease production by A. oryzae. Further, the utilization of deoiled J. curcas seed cake as substrate for SSF was proven as the suitable practice for this agricultural waste, in order to develop for an industrial use.