Transesterification of palm oil to methyl ester on activated carbon supported calcium oxide catalyst

In this study, methyl ester (ME) was produced by transesterification of palm oil (CPO) (cooking grade) using activated carbon supported calcium oxide as a solid base catalyst (CaO/AC). Response surface methodology (RSM) based on central composite design (CCD) was used to optimize the effect of reaction time, molar ratio of methanol to oil, reaction temperature and catalyst amount on the transesterification process. The optimum condition for CPO transesterification to methyl ester was obtained at 5.5 wt.% catalyst amount, 190 °C temperature, 15:1 methanol to oil molar ratio and 1 h 21 min reaction time. At the optimum condition, the ME content was 80.98%, which is well within the predicted value of the model. Catalyst regeneration studies indicate that the catalyst performance is sustained after two cycles.     

Synthesis of fatty acid methyl ester from palm oil (Elaeis guineensis) with Ky(MgCa)2xO3 as heterogeneous catalyst

Fatty acid methyl esters (FAME) were produced from palm oil using eggshell modified with magnesium and potassium nitrates to form a composite, low-cost heterogeneous catalyst for transesterification. The catalyst, prepared by the combination of impregnation/co-precipitation was calcined at 830 °C for 4 h. Transesterification was conducted at a constant temperature of 65 °C in a batch reactor. Design of experiment (DOE) was used to optimize the reaction parameters, and the conditions that gave highest yield of FAME (85.8%) was 5.35 wt.% catalyst loading at 4.5 h with 16:1 methanol/oil molar ratio. The results revealed that eggshell, a solid waste, can be utilized as low-cost catalyst after modification with magnesium and potassium nitrates for biodiesel production.     

Synthesis of fatty acid methyl ester from crude jatropha (Jatropha curcas Linnaeus) oil using aluminium oxide modified Mg-Zn heterogeneous catalyst

The synthesis of fatty acid methyl esters (FAME) as a substitute to petroleum diesel was investigated in this study from crude jatropha oil (CJO), a non-edible, low-cost alternative feedstock, using aluminium modified heterogeneous basic oxide (Mg-Zn) catalyst. The transesterification reaction with methanol to methyl esters yielded 94% in 6 h with methanol-oil ratio of 11:1, catalyst loading of 8.68 wt.% at 182 °C and the properties of CJO fuel produced were determine and found to be comparable to the standards according to ASTM. In the range of experimental parameters investigated, it showed that the catalyst is selective to production of methyl esters from oil with high free fatty acid (FFA) and water content of 7.23% and 3.28%, respectively in a single stage process. Thus, jatropha oil is a promising feedstock for methyl ester production and large scale cultivation will help to reduce the product cost.     

Circadian control of isoprene emissions from oil palm (Elaeis guineensis)

The emission of isoprene from the biosphere to the atmosphere has a profound effect on the Earth's atmospheric system. Until now, it has been assumed that the primary short-term controls on isoprene emission are photosynthetically active radiation and temperature. Here we show that isoprene emissions from a tropical tree (oil palm, Elaeis guineensis) are under strong circadian control, and that the circadian clock is potentially able to gate light-induced isoprene emissions. These rhythms are robustly temperature compensated with isoprene emissions still under circadian control at 38 degrees C. This is well beyond the acknowledged temperature range of all previously described circadian phenomena in plants. Furthermore, rhythmic expression of LHY/CCA1, a genetic component of the central clock in Arabidopsis thaliana, is still maintained at these elevated temperatures in oil palm. Maintenance of the CCA1/LHY-TOC1 molecular oscillator at these temperatures in oil palm allows for the possibility that this system is involved in the control of isoprene emission rhythms. This study contradicts the accepted theory that isoprene emissions are primarily light-induced.     

Phenological growth stages of African oil palm (Elaeis guineensis)

The aim of this paper was to study the phenology of commercially cultivated representative genotypes of the Elaeis guineensis Jacq. species in two Colombian growing areas. The frequency of observations was daily, weekly or monthly depending on the stage of development under evaluation, over an 18‐month time period. Observations were made on prenursery and nursery plants and on three‐ to five‐year‐old palms starting from the zero leaf (spear leaf), through development of inflorescence, and ending with maturity and harvesting of fruit bunches. Stem observations were made on different age palms of the same cultivars. The duration of each phenological stage was measured in terms of days. The phenological growth stages were coded according to the BBCH scale (Biologische Bundesantalt, Bundessortenamt und Chemische Industrie), consisting of three digits, because of the inclusion of intermediate stages between the principal and secondary stages in order to provide more accurate details on each development stage.     

Production of biodiesel from mixed waste vegetable oil using an aluminium hydrogen sulphate as a heterogeneous acid catalyst

Al(HSO₄)₃ heterogeneous acid catalyst was prepared by the sulfonation of anhydrous AlCl₃. This catalyst was employed to catalyze transesterification reaction to synthesis methyl ester when a mixed waste vegetable oil was used as feedstock. The physical and chemical properties of aluminum hydrogen sulphate catalyst were characterized by scanning electron microscopy (SEM) measurements, energy dispersive X-ray (EDAX) analysis and titration method. The maximum conversion of triglyceride was achieved as 81 wt.% with 50 min reaction time at 220 °C, 16:1 molar ratio of methanol to oil and 0.5 wt.% of catalyst. The high catalytic activity and stability of this catalyst was related to its high acid site density (-OH, Brönsted acid sites), hydrophobicity that prevented the hydration of -OH group, hydrophilic functional groups (-SO₃H) that gave improved accessibility of methanol to the triglyceride. The fuel properties of methyl ester were analyzed. The fuel properties were found to be observed within the limits of ASTM D6751.     

Biodiesel production via transesterification of palm olein using waste mud crab (Scylla serrata) shell as a heterogeneous catalyst

A recent rise in crab aquaculture activities has intensified the generation of waste shells. In the present study, the waste shells were utilized as a source of calcium oxide to transesterify palm olein into methyl esters (biodiesel). Characterization results revealed that the main component of the shell is calcium carbonate which transformed into calcium oxide when activated above 700 °C for 2 h. Parametric studies have been investigated and optimal conditions were found to be methanol/oil mass ratio, 0.5:1; catalyst amount, 5 wt.%; reaction temperature, 65 °C; and a stirring rate of 500 rpm. The waste catalyst performs equally well as laboratory CaO, thus creating another low-cost catalyst source for producing biodiesel. Reusability results confirmed that the prepared catalyst is able to be reemployed up to 11 times. Statistical analysis has been performed using a Central Composite Design to evaluate the contribution and performance of the parameters on biodiesel purity.     

Analysis of expressed sequence tags from oil palm (Elaeis guineensis)

This is the first report of a systematic study of genes expressed by means of expressed sequence tag (EST) analysis in oil palm, a species of the Arecales order, a phylogenetically key clade of monocotyledons that is not widely represented in the sequence databases. Five different cDNA libraries were generated from male and female inflorescences, shoot apices and zygotic embryos and unidirectional systematic sequencing was performed. A total of 2411 valid EST sequences were thus obtained. Cluster analysis enabled the identification of 209 groups of related sequences and 1874 singletons. Putative functions were assigned to 1252 of the set of 2083 non-redundant ESTs obtained. The EST database described here is a first step towards gene discovery and cDNA array-based expression analysis in oil palm.     

Biodiesel production from rubber seed oil using poly (sodium acrylate) supporting NaOH as a water-resistant catalyst

Poly (sodium acrylate) supporting NaOH (NaOH/NaPAA) was prepared by in situ polymerization of aqueous solution of acrylic acid with an over-neutralization by adding excess of NaOH. NaOH/NaPAA presented a promising selectivity for water absorbency and good water retention with negligible swelling capacity in the organic solvents of methanol, glycerol, rubber seed oil methyl esters, and rubber seed oil. NaOH/NaPAA catalysts showed a basic strength of 15.0 < H_ < 18.4 and their basicity increased with the increase of the NaOH loading amount. NaOH/NaPAA catalysts exhibited almost the same catalytic activity in the transesterification of rubber seed oil with methanol under the optimized reaction conditions compared to conventional homogeneous NaOH catalyst. Furthermore, the functional absorbent/catalyst system presented a good water resistance in the transesterification which retained high catalytic activity when a water concentration in the reaction system was less than 2 wt.%.     

Growth of oil palm (Elaeis guineensis) seedlings on acid sulfate soils as affected by water regime and aluminium

In Malaysia, acid sulfate soils contain high amounts of aluminium and are usually utilized for oil palm cultivation. As these soils are frequently flooded during rainy periods, it is thought that this may affect the growth performance of the oil palm. A glasshouse experiment was, therefore, conducted to study the effects of water regime and aluminium on the growth of oil palm seedlings. Soils used in the experiment were Typic Sulfaquepts and Sulfic Tropaquepts from Pulau Lumut Island, Malaysia. Best growth was observed on a non-jarositic freely drained topsoil. Oil palm seedlings were found the be moderately tolerant to soil acidity. Growth was only affected if Al³⁺ and Al_sum activities in the soil solutions were above 100 and 700 M, respectively. Root length was found to be one of the better parameters to predict crop growth, while others included plant height, fron length and LAI. Soil solution attributes which could be used as indices of soil acidity for oil palm growth were pH and activities of Al³⁺, AlSO₄ ⁺ and Al_sum.     

Purification and characterization of soluble peroxidase from oil palm (Elaeis guineensis Jacq) leaf

Soluble peroxidase (POD) from oil palm leaf was purified by (NH(4))(2)SO(4) precipitation, anion exchange chromatography and molecular exclusion chromatography. The purification grade obtained was 429 yielding 54% of the enzyme activity. Electrophoresis of purified enzyme under denatured conditions revealed M(r) of 48+/-2 kDa. It has an optimum pH of 5 and it exhibited very high pH and thermal stabilities. K(m) for guaiacol, ABTS and pyrogallol were 3.96, 1 and 0.84 mM, respectively. Immunocytochemical localization studies showed that soluble POD was mainly located in the vascular bundles and epidermis of leaf.     

Preparation of solid acid catalyst from glucose-starch mixture for biodiesel production

The aim of this work is to study the catalyst prepared by glucose-starch mixture. Assessment experiments showed that solid acid behaved the highest esterification activity when glucose and corn powder were mixed at ratio of 1:1, carbonized at 400 °C for 75 min and sulfonated with concentrated H₂SO₄ (98%) at 150 °C for 5 h. The catalyst was characterized by acid activity measurement, XPS, TEM and FT-IR. The results indicated that solid acid composed of CS_0.073O_0.541 has both Lewis acid sites and Broˇnsted acid sites caused by SO₃H and COOH. The conversions of oleic acid esterification and triolein transesterification are 96% and 60%, respectively. Catalyst for biodiesel production from waste cottonseed oil containing high free fatty acid (FFA 55.2 wt.%) afforded the methyl ester yield of about 90% after 12 h. The catalyst deactivated gradually after recycles usage, but it could be regenerated by H₂SO₄ treatment.     

Cryopreservation of oil palm (Elaeis guineensis Jacq.) somatic embryos involving a desiccation step

Summary The standard cryopreservation process previously developed for oil palm clones using shiny white, finger-like somatic embryos could be applied in some cases to standard cultures. Its efficiency was markedly improved by completing the 7-day pregrowth period on 0.75 M sucrose by an additional dehydration period carried out either by placing the embryos in the air current of the laminar flow cabinet or in an air tight box containing silica gel. This improved process was successfully applied to 7 different clones. It will facilitate the routine uof cryopreservation for oil palm cultures.     

Conversion of waste produced by the deodorization of palm oil as feedstock for the production of biodiesel using a catalyst prepared from waste material

The distillate produced by deodorization of palm oil (DDPO) is a waste that corresponds to 4% of the product formed in this process. DDPO is 83% free of fatty acids (FFA), making it a good material for biodiesel production. In this paper, a catalyst prepared from a waste material, Amazon flint kaolin, was used for the esterification of DDPO with methanol. Leached metakaolin treated at 950 °C and activated with 4 M sulfuric acid (labeled as MF9S4) offered maximum esterification activity (92.8%) at 160 °C with a DDPO:methanol molar ratio of 1:60 and a 4-h reaction time. The influences of reaction parameters, such as the molar ratio of the reactants, alcohol chain length, temperature, time and the presence of glycerides and unsaponifiable matter, have also been investigated. Based on the catalytic results, esterification of DDPO using MF9S4 can be a cheaper alternative for production of sustainable fuels.     

The shoot apical meristem of oil palm (Elaeis guineensis; Arecaceae): developmental progression and dynamics

Background and Aims

Oil palm, an unbranched perennial monocotyledon, possesses a single shoot apical meristem (SAM), which is responsible for the initiation of the entire above-ground structure of the plant. To compare the palm SAM structure with those of other monocots and to study variations in its structure throughout the life of the plant, its organization was characterized from the embryonic stage to that of the reproductive plant.

Methods

SAM structure was studied by a combination of stained histological sections, light and confocal microscopy, and serial section-based three-dimensional reconstructions.

Key Results

The oil palm SAM is characterized by two developmental phases: a juvenile phase with a single tunica-corpus structure displaying a gradual increase in size; and a mature phase characterized by a stable size, a modified shape and an established histological zonation pattern. In mature plants, fluctuations in SAM shape and volume occur, mainly as a consequence of changes in the central zone, possibly in relation to leaf initiation.

Conclusions

Development of the oil palm SAM is characterized by a juvenile to mature phase transition accompanied by establishment of a zonal pattern and modified shape. SAM zonation is dynamic during the plastochron period and displays distinct features compared with other monocots.     

Purification and characterisation of acyl-CoA: glycerol 3-phosphate acyltransferase from oil palm (Elaeis guineensis) tissues

Glycerol 3-phosphate acyltransferase (GPAT, EC 2.3.15) catalyses the first step of the Kennedy pathway for acyl lipid formation. This enzyme was studied using high-speed particulate fractions from oil palm (Elaeis guineensis Jacq.) tissue cultures and mesocarp acetone powders. The fractions were incubated with [¹⁴C]glycerol 3-phosphate and incorporation of radioactivity into Kennedy pathway intermediates studied. Optimal conditions were broadly similar between the two preparations but those from fruit mesocarp clearly contained more active enzymes for the subsequent stages of the Kennedy pathway – as exemplified by the appreciable accumulation of radioactivity in triacylglycerol. Experiments with different acyl-CoA substrates showed that the GPAT in both high-speed particulate preparations had a significant preference for palmitate. Glycerol 3-phosphate acyltransferase was solubilised from both preparations with optimal solubilisation being achieved at 0.5% (w/v) CHAPS concentrations. Solubilised GPATs were purified further using DE52 ion-exchange chromatography and Sephadex G-100 molecular exclusion chromatography. Purifications of up to about 70-fold were achieved. The purified GPATs showed a strong preference for palmitoyl-CoA compared to other acyl-CoA donors, in keeping with the importance of palmitate in palm oil. Received: 22 April 1999 / Accepted: 29 July 1999     

Phenology and growth adjustments of oil palm (Elaeis guineensis) to photoperiod and climate variability

Background and Aims

Oil palm flowering and fruit production show seasonal maxima whose causes are unknown. Drought periods confound these rhythms, making it difficult to analyse or predict dynamics of production. The present work aims to analyse phenological and growth responses of adult oil palms to seasonal and inter-annual climatic variability.

Methods

Two oil palm genotypes planted in a replicated design at two sites in Indonesia underwent monthly observations during 22 months in 2006–2008. Measurements included growth of vegetative and reproductive organs, morphology and phenology. Drought was estimated from climatic water balance (rainfall – potential evapotranspiration) and simulated fraction of transpirable soil water. Production history of the same plants for 2001–2005 was used for inter-annual analyses.

Key Results

Drought was absent at the equatorial Kandista site (0°55′N) but the Batu Mulia site (3°12′S) had a dry season with variable severity. Vegetative growth and leaf appearance rate fluctuated with drought level. Yield of fruit, a function of the number of female inflorescences produced, was negatively correlated with photoperiod at Kandista. Dual annual maxima were observed supporting a recent theory of circadian control. The photoperiod-sensitive phases were estimated at 9 (or 9 + 12 × n) months before bunch maturity for a given phytomer. The main sensitive phase for drought effects was estimated at 29 months before bunch maturity, presumably associated with inflorescence sex determination.

Conclusion

It is assumed that seasonal peaks of flowering in oil palm are controlled even near the equator by photoperiod response within a phytomer. These patterns are confounded with drought effects that affect flowering (yield) with long time-lag. Resulting dynamics are complex, but if the present results are confirmed it will be possible to predict them with models.     

Ranking the value of germplasm: new oil palm (Elaeis guineensis) breeding stocks as a case study

Plant breeders constantly need to introduce desirable new alleles to refresh breeding stocks. This first requires an assessment of potential new sources of material and then identification of genotypes most able to augment existing stocks. Genetic distance analysis is widely used for both purposes, although it measures both haplotype diversity and novel allele abundance. Here, we present a more tailored approach to address these problems. Using oil palm as an exemplar, simple metrics of allelic and genetic richness, graphical genotyping and multivariate analysis were deployed to determine the overall value of Ghanaian germplasm to supplement Sumatra Bioscience (SumBio) breeding material. We next compared three methods to rank individuals. The first was based on multivariate genetic distance. However, we also developed two new systems: Global Allelic Divergence (GAD), based on novel allele abundance, and Genome Scan Allelic (GSA) divergence, which additionally considers genome context. Ghanaian material exhibited increased allelic richness, higher heterozygosity and a higher proportion of private alleles than extant SumBio breeding stocks. Graphical genotyping revealed Ghanaian material as allele‐rich in genomic regions that were allele‐poor in SumBio breeding stocks. Multivariate analysis showed a collective distinctness and increased variability of Ghanaian plants. Ranks of individuals varied between GSA, GAD and genetic distance. The GAD and GSA ranks correlated strongly with each other but only poorly with the genetic distance‐based ranks. We conclude that GSA and GAD are superior ranking systems to identify individuals most likely to introduce valuable new alleles, whilst genetic distance analysis identifies individuals likely to require least backcrossing.     

Silica-bonded N-propyl sulfamic acid used as a heterogeneous catalyst for transesterification of soybean oil with methanol

The transesterification of soybean oil with methanol was carried out, to produce biodiesel, over silica-bonded N-propyl sulfamic acid in a heterogeneous manner. Results showed that a maximum conversion of 90.5% was achieved using a 1:20 M ratio of soybean oil to methanol and a catalyst amount of 7.5 wt.% at 423 K for 60 h. It was found that the free fatty acid (FFA) and water present in the feedstock had no significant influence on the catalytic activity to the transesterification reaction. Besides, the catalyst also showed activities towards the esterification reaction of FFAs, in terms of the FFA conversion of 95.6% at 423 K for 30 h. Furthermore, the catalyst could be recovered with a better reusability.     

Prediction of oil palm (Elaeis guineensis, Jacq.) agronomic performances using the best linear unbiased predictor (BLUP)

Reciprocal recurrent selection (RRS) has been adopted for oil palm breeding in Indonesia.Due to a long selection cycle and the large area required, a satisfactory oil palm progeny trial is difficult to conduct.Knowledge of the parental genetic parametersis very important in achieving the expected genetic progress, but the evaluation of these parameters is constrained by highly unbalanced data sets. In this study, the unbalanced agronomic data sets and the pedigree information of an oil palm breeding programme in Indonesia were analysed by using the restricted maximum likelihood (REML) and the best linear unbiased predictor (BLUP)methods. The characters analysed were bunch and oil yields of the adult period (from 7 to 9 years after planting). The coefficients of parentage varied from 0.125 to 0.891 and from zero to 0.750 between parents in the Deli and African groups, respectively.The average coefficients of inbreeding were 0.269 and 0.166 for the parents within the Deli and African groups, respectively. The additive variances of the bunch number, industrial oil-extraction rate and oil yield characters were higher in the parents of the Deli group than those in the African ones. The coefficients of correlation between the predicted and observed hybrids performances varied from 0.55 to 0.64 for oil yield, 0.49 to 0.71 for bunch number, 0.47 to 0.58 for bunch production, 0.48 to 0.64 for industrial oil-extraction rate and 0.42 to 0.56 for plant-height increment. For selection on the basis of oil yield character, BLUPs ability to predict single-cross performance should be sufficient, and will result in a significant contribution to the oil palm seed and clone productions. Received: 3 January 2000 / Accepted: 3 July 2000