Category Archives: 2012 Vol 24 Dec

A bibliometric study on the worldwide research productivity of scientists in Elaeis guineensis Jacq. and Elaeis oleifera

This article has the general aim of assessing the worldwide research productivity of Elaeis guineensis Jacq. and Elaeis oleifera or more commonly known as oil palm, as reflected by the literature indexed in the Web of Science (WoS) and Scopus databases. Specifically, the research aims to identify the most productive countries, institutions and authors in this area of research. It also investigates the subject characteristics of the publication and collaborative patterns among researchers and institutions. Overall, based on the number of publications indexed by both WoS and Scopus, the Asian region, represented by seven countries, are the dominant producers of publications in this field, of which Malaysia is in the number one position. Whereas, USA and some European countries, such as United Kingdom and France, are also leading in terms of publications and citations. Research in the areas of food science and technology (WoS) as well as agricultural and biological sciences (Scopus) account for the highest number of publications. High levels of collaboration among authors are evident among the top 10 most productive countries. This is a good indication of collaboration impact with increased research output.

The estimation of frond base biomass (FBB) of oil palm

Increasing attention is being focused on the greenhouse gas (GHG) balance of crop production given the need to minimise emissions associated with global warming and climate change. Such emissions can be countered by growing crops such as oil palm that have a high capacity to sequester carbon. The ability to accurately determine carbon sequestration by the crop thus becomes increasingly important. In the case of oil palm, methods of estimating crop biomass are well developed. However, there are still improvements to be made to ensure a complete assessment of carbon stock. This article examines the role carbon sequestration played by frond bases of oil palm that remain attached to the trunk after frond pruning, and which are frequently ignored when assessing standing palm biomass and carbon stock. Data on frond base biomass (FBB) are reviewed, methods for its assessment are discussed, and its importance for calculating carbon sequestration and net carbon balance of oil palm plantations are examined. Carbon sequestration in the plantation for four mills in Papua New Guinea, with a mean crop rotation time of 21 years in their contributing estates was increased by an average of 11% after including FBB in the calculation of standing carbon.

The isolation and characterisation of oil palm (Elaeis guineensis Jacq.) β-ketoacy-acyl carrier protein (ACP) synthase (KAS) II cDNA

Modulating endogenous levels and/or producing novel fatty acids of oils have gained significant attention in recent years to meet the demand for oils for specific markets. The commodity palm oil is composed mainly of four fatty acids: palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1) and linoleic acid (18:2). The percentages of these fatty acids in palm oil average 44%, 4%, 39% and 10%, respectively, with trace amounts of other fatty acids. Metabolic engineering may be used to produce oil crops with desired fatty acid compositions. We have isolated and characterised β-ketoacyl ACP-synthase II (KASII) cDNA from oil palm (Elaeis guineensis) which is one of the main components for the oil palm genetic engineering programme. KAS II is associated with the accumulation of palmitic acid in oil palm, and its role in controlling the ratio of C16:C18 has been previously determined. We isolated KAS II cDNA from oil palm, and functionally characterised the same in Escherichia coli and Arabidopsis. Partial length KAS II cDNA was first obtained by the reverse transcriptase-polymerase chain reaction (RT-PCR). Rapid amplification of cDNA ends (RACE) was then used to isolate both the 5’ and 3’ ends of the KAS II sequences. Assembly of the partial length sequence fragments, including the 5’ and 3’ ends, allowed for the full-length sequence information on the KAS II cDNA to be obtained and used in the gene isolation. Expression studies in E. coli resulted in an increase in oleic acid at the expense of palmitic acid. Arabidopsis thaliana was also used to further confirm the functional activity of the oil palm KAS II. A significant decrease in C18:0 and accumulation of C16:0 were detected in the plants that had been transformed with the antisense KASII construct. This suggests that the substrate specificity of the oil palm KAS II is similar to that of KAS II from other plants which preferentially elongate palmitic to stearic acids. The oil palm KAS II may, therefore, be useful in providing new opportunities in the genetic engineering programme for the production of high-value products such as an oil with a high content of monounsaturated fatty acids from the transgenic oil crops.

Reduction in free fatty acids in crude palm oil by enzymatic remediation

Fatty acids present in crude palm oil are normally removed in processing and result in a yield loss. This investigation studied if they could be recovered through an enzymatic condensation reaction. Free fatty acids (FFA) present in crude palm oil at a level of 4.8%-7.2% could be converted back to triacyl glycerols utilising a microbial esterase to perform a condensation reaction with mono and diglycerides present in the oil. The rate of removal of fatty acids could be increased by the addition of glycerol to provide more sites for attachment. However, the addition of glycerol resulted in an increase in the mono and diglyceride content of the oil as the fatty acid preferentially attached to this molecule. In a glycerol free system, the reduction in fatty acids was achieved when an immobilised form of the enzyme was used. This enzyme did not cause significant interesterification of the palm oil, an advantage for later fractionation. An addition of a small amount of palmitic acid (3% w/w), to the reaction gave a lower residual level of mono and diglycerides compared to a reaction with only the intrinsic level of FFA.

Pyrolsis of oil palm biomass using palm shell char as microwave absorber

The main aim of this research was to reveal the heating characteristics of palm shell char (PSC) acting as a microwave absorber (MA) for the pyrolysis of oil palm biomass (shell and fibre). This was done by mixing oil palm biomass with PSC-MA and subjecting it to microwave irradiation. A domestic microwave oven with a maximum power of 1000 W and 2.45 GHz frequency was used. Prior to pyrolysis, the heating characteristic of PSC-MA in terms of its temperature profile (through batch and continuous temperature measurements) was examined. It was found that PSC-MA could act as very good microwave receptor. However, the method of temperature measurement played an important role in the heating and pyrolysis behaviour. A minimum microwave power of 450 W was needed to carry out the pyrolysis process in the present work. Results of the microwave pyrolysis show that the ratio of biomass to PSC-MA has a significant influence on the product yield. A synergistic effect between PSC-MA and the biomass can reduce the consumption of energy, time and cost of the thermo-chemical process.

Greenhouse gas emissions for the production of crude palm kernel oil – a gate-to-gate case study

Currently, carbon footprint, also known as greenhouse gas (GHG) emissions, is such a catchphrase in the world that it has become a must for responsible producers to quantify the carbon footprint of their products. The Malaysian oil palm industry is an export-orientated industry which relies heavily on the world market. Export earnings of oil palm products in 2010 alone reached RM 59.77 billion, while palm kernel oil exports increased to 1.16 million tonnes. However, the oil palm industry is under constant attack for its performance from the perspective of the environment, especially with regard to its GHG emissions. Being an export-orientated industry, this issue has to be tackled head-on to quantify the GHG emissions of the oil palm industry. The objectives of this study were to quantify the GHG emissions from the production of 1 t of crude palm kernel oil (CPKO) at the kernel-crushing plant, and to compare the GHG emissions of 1 t CPKO with and without biogas capture at the palm oil mill for a kernel-crushing plant located near the ports compared to a kernel-crushing plant located near the palm oil mill. The scope of this study is limited to the palm oil mill and the kernel-crushing plant. It starts at the palm oil mill where the fresh fruit bunches (FFB) are received, to the production of palm kernel at the mill, to the transportation of the palm kernel to the kernel-crushing plant, right up till the production of CPKO at the kernel-crushing plant. GHG emission was calculated using the global warming potential and emissions factors. Within the system boundary, the main contributor to GHG emission comes from the biogas at the palm oil mill, followed by the electricity from the grid for processing the palm kernel into CPKO. Capturing the biogas at the palm oil mill where the palm kernel is produced and using the biogas as a renewable energy source, reduces the main GHG emissions in this study. By integrating the kernel-crushing plant with the palm oil mill, GHG emissions from both the electricity to process the palm kernel into CPKO and transportation of the palm kernel to the kernel-crushing plant are reduced significantly. The best scenario will be to integrate the kernel-crushing plant with a palm oil mill that captures its biogas to obtain the best carbon footprint for the production of CPKO.

A two step chemo-enzymatic method for the synthesis of fatty acid ascorbyl esters

Fatty acid vinyl esters were synthesised from the corresponding free fatty acids in 79%-84% yield using Hg (OAc)2/H2SO4 under microwave irradiation. Subsequently, the obtained fatty acid vinyl esters were utilised for the lipase catalysed acylation of vitamin C under microwave heating. Various lipases viz. Pseudomonas cepacia, Porcine pancreatic, Candida rugosa, Mucor miehei, Rhizopus oryzae and Novozyme-435 were screened for the acylation of vitamin C under microwave irradiation. Among these lipases, Novozyme-435 was found to be the best catalyst for this reaction. Five different ascorbyl esters were synthesised in 58%-85% yield in 3 hr using Novozyme-435.

Phenol adsorption by activated carbon of different fibre size derived from empty fruit bunches

The capacity of empty fruit bunch-based activated carbon for phenol adsorption was studied. Four different particle sizes of activated carbon (AC) (unsieved, > 2, 0.355-1.0 and < 0.15 mm mesh number) were produced by the activation of prepared charcoal with CO2. Activated carbon with particle size greater than 2 mm demonstrated the highest percentage of phenol adsorption. The performance of this activated carbon in phenol removal was better than commercially available activated carbon with an adsorption capacity of the AC sample and the commercial AC at equilibrium time amounting to 73% and 68%, respectively. The experimental data were analysed using the Langmuir and Freundlich adsorption models. The kinetics of adsorption were well described by a pseudo-second order model, whilst the adsorption equilibrium was best represented by the Langmuir isotherm model.

Oil palm adaptation to compacted alluvial soil (Typic Endoaquepts) in Malaysia

A study was carried out to evaluate the ability of oil palm to adapt to compacted Bernam series soil (Typic Endoaquepts). After six years of soil compaction treatments, the mean soil bulk density, available water as well as the percentages of mesopores and micropores increased, whereas total porosity, hydraulic conductivity, infiltration rate and percentage of macropores decreased. Fresh fruit bunch (FFB) yield increased significantly with increased mean soil bulk density. On the other hand, the treatments resulted in significant reductions in oil palm standing biomass, root biomass as well as frond dry weight. Total green frond number, total leaf area and leaf area index were not affected by the treatments. The growth of oil palm roots was significantly affected by the compacted soil, resulting in lower primary and secondary root production, but compensated for by the production of longer and thicker tertiary and quaternary roots. The treatments caused changes in the soil physical properties and resulted in soil compaction, which then affected oil palm performance. The palms showed adaptation to these changes and responded positively by producing better yield following the compaction treatments. This shows that compacted soil may not be a problem to oil palm planted in the Bernam series soil.

Vermicomposting of empty fruit bunch with addition of palm oil mill effluent solid

The aim of the present study was to evaluate the quality of the nutrients of the vermicompost produced from oil palm empty fruit bunches (EFB) mixed with palm oil mill effluent (POME) solid employing an epigeic earthworm Eisenia fetida. The vermicomposting of EFB and in supplementation with POME solid differed in the resulting C/N ratios. The initial C/N ratios (178.1, 114.5, 153.3, 73.1, 123.1 and 38.6) for the six vermicomposters were significantly reduced to 54.0, 20.1, 19.5, 12.1, 15.5, and 10.5, respectively, after 84 days of vermicomposting. A significant increase in pH, TKN, TP and TK content was recorded in all the vermicomposters (V1, V2, V3, V4, V5 and V6). From this study, we can conclude that of the six compositions studied, the best ratio for vermicomposting of EFB with additional POME is V6 (50% EFB + 50% POME solid).

Effects of tocotrienol supplementation on pregnancy outcome in mice subjected to maternal corticosterone administration

The present study was designed to observe the beneficial effects of tocotrienol (TCT) supplementation on pregnancy outcome in corticosterone (CORT)-treated mice. CORT is reported to adversely affect pregnancy outcomes in mice. Seven- to eight-week-old female mice (Mus musculus) were divided into five groups and subjected to their respective treatment for the first seven days of pregnancy. Group 1 (control group) had 0.1 ml corn oil intraperitoneal (ip) and orally per day. Group 2 had CORT (10 mg kg-1 in 0.1 ml corn oil) ip and 0.1 ml corn oil orally per day. Animals of Group 3, 4 and 5 received CORT concurrently with TCT at the dose of 60, 90 and 120 mg kg-1 in 0.1 ml corn oil orally per day. On Day 7 of pregnancy, laparotomy was done to determine the number of implantation sites and to observe any resorption signs. Litter sizes were measured at birth and compared with the number of implantations to determine the resorption rate in various groups. The results of this study showed that the number of implantation sites in the group treated with CORT and 120 mg kg-1 TCT (Group 5) was significantly higher (p<0.05) as compared to CORT-treated mice (Group 2). On the other hand, the resorption rate in CORT-treated mice (Group 2) was significantly higher (p<0.001) as compared to control (Group 1). Conversely, TCT at the dose of 120 mg kg-1 given to CORT-treated mice (Group 5) reduced the resorption rate towards control. Therefore, the optimum dose of TCT that is able to overcome the effect of CORT on the implantation numbers and resorption rate is 120 mg kg-1 body weight (BW). This finding suggests that TCT administration is able to reverse the adverse effects of CORT on pregnancy outcome.

Quality of palm fatty acid distillate (PFAD) upon storage: effect of mild steel

A study to evaluate the effects of interaction between mild steel and palm fatty acid distillates (PFAD) on the quality of PFAD was carried out. PFAD was stored at 65°C in the presence of mild steel strips. Iron content analysis showed that PFAD is a reasonably corrosive material to mild steel and the rate of iron picked up by PFAD was found to be quite rapid at 65°C. This rapid iron pick up resulted in the deterioration of PFAD in terms of its oxidative parameters, due to the known catalytic effect of iron. It is recommended that the avoidance of contact between mild steel and PFAD at high temperatures should be practised, in order to prevent a rapid deterioration of PFAD quality.

Palm oil diets do not raise total/hdl-cholesterol compared to a partially hydrogenated vegetable oil diet in rats

A suitable replacement fat for a trans fat rich partially hydrogenated vegetable oil (PHVO) has to be chosen and examined carefully before being introduced for any food applications. The aim of the replacement is to avoid putting the subgroups in Southeast Asia at risk of having high trans fatty acid content in their diets. A direct comparison between the effects of PHVO and unhydrogenated vegetable oils on blood lipids has not been evaluated extensively. Therefore, the objective of this study was to compare the effects of different unhydrogenated vegetable oils, using high oleic palm olein (HOPOo), palm oil (PO), and palm stearin (POs), on serum lipid levels with those of PHVO. Male Sprague Dawley rats (n=14 per group) were randomly allocated an isoenergetic meal, providing 34.0% of the total energy from fat, from one of the formulated diets for eight weeks. HOPO, PO and POs were used as sources of unhydrogenated PO in the diets while a PHVO obtained from soyabean oil was used as a positive control. Our study demonstrated that HOPOo, PO and POs did not raise total/high density lipoprotein cholesterol (HDL-c) compared with PHVO. Food intake was monitored during the feeding intervention. All the unhydrogenated palm oil diets exerted similar incremental body weights compared to PHVO. The present study confirmed that the three unhydrogenated PO diets did not adversely affect blood lipids compared with PHVO in rats.

Production of live food from palm oil mill effluent (POME) for culture of marble goby

For the first time a phototrophic bacterium, Rhodovulum sulfidophilum grown in palm oil mill effluent (POME-PB) was successfully used as food for rotifers (Brachionus rotundiformis) and Artemia nauplii which were then fed to the larvae of the marble goby, Oxyeleotris marmorata. The cultivation of POME-PB is cheap and easy where it can be easily produced in sealed, plastic ziplock bags exposed to light, giving a harvestable biomass of 2.58 ± 0.34 g litre-1 after 60 hr post-inoculation. Rotifers fed the biomass of settled bacteria (sPOME-PB) had comparable mean density (221 ± 9 rotifers ml-1) as rotifers fed with microalgae Nannochloropsis sp. (212 ± 27 rotifers ml-1). However, unsettled bacterial culture (uPOME-PB) fed to rotifers resulted in higher rotifer densities of up to 898 ± 489 rotifers ml-1. By feeding the marble goby larvae with rotifers and Artemia nauplii cultured in uPOME-PB, a mean survival of 81.9 ± 3.0% was obtained for 30-day post-hatch fish larvae. This survival was much higher than fish larvae given rotifers and Artemia nauplii fed sPOME-PB (42.5 ± 9.0%; 71.4 ± 20.5%) and Nannochloropsis sp. (46.8 ± 2.9%). POME-PB thus has the potential to be an aquaculture feed for the future.