Category Archives: 2019 Vol 31 Dec

INFLUENCE OF SURFACTANT STRUCTURE ON PHYSICAL STABILITY AND PHYSICOCHEMICAL PROPERTIES OF INSECTICIDE EMULSIONS

A stable oil-in-water (o/w) emulsion to combat mosquitoes has been successfully formulated using palm methyl ester (PME) as carrier solvent, xanthan gum (XG) as thickener and plant-based non-ionic surfactants. The performance of castor oil-based surfactant, polyethylene glycol (20) glyceryl oleoricinoleate (PEG 20G), coupled with palm-based polyoxyethylene (20) sorbitan monooleate (POE 20S) was compared with conventional palm-based surfactant, C12-C14 fatty alcohol ethoxylate (FAE), coupled with POE 20S. The effects of surfactant mixing ratios and total thickener concentrations on stability, droplet size, microstructure and viscosity of the resulting emulsions were investigated. Emulsions obtained with a mixture of the two palm-based surfactants exhibited superior emulsification efficiency and stability in comparison to emulsions obtained with a mixture of castor oil and palm-based surfactant. The results indicated that the molecular structure of palm-based surfactants positively affect surfactant packing conformation at the oil/aqueous phase interface. The present study opens the possibility of using palm-based surfactants in insecticide emulsions in an effort to curb the spread of mosquito-borne diseases around the world.

PALM-BASED VITAMIN E (tocotrienol-rich fraction) HAS EXCELLENT STABILITY IN CHEWABLE TABLET AFTER ONE-YEAR OF STORAGE AT AMBIENT TEMPERATURE

Palm oil is a good source of micronutrients (sometimes called phytonutrients as they are plant-based). The micronutrients constitute about 1% of crude palm oil. Vitamin E is the most abundant micronutrient of palm oil. Other prevalent micronutrients found in palm oil are carotenes, phytosterols, squalene, coenzyme Q10 (ubiquinone), phospholipids (lecithin) and polyphenols. Palm-based vitamin E, also known as tocotrienol-rich fraction (TRF) has been used as a dietary supplement in the form of soft gel capsules, but there is relatively little information about its contribution when processed into a chewable tablet. Stability of the micronutrient during storage is a critical factor to be considered. Based on the general instability of vitamins, endogenous and added vitamins can suffer substantial losses during storage prior to consumption. The retention of vitamin E in the palm-based TRF chewable tablet after one-year storage at ambient temperature was 92.6%. The excellent retention of vitamin E in the chewable tablet was most plausible due to the use of powdered (microencapsulated) palm-based TRF which managed to protect the bioactive component from direct exposure to chemical and physical reactions, thus protecting the bioactive ingredient from degradation. This study indicates that powdered palm-based TRF has good stability during storage and it can be effectively delivered via a chewable tablet form to consumers.

A DESCRIPTION OF OPEN TOP CHAMBER SYSTEM FOR OIL PALM CARBON DIOXIDE ENRICHMENT

Open Top Chamber (OTC) is one of the techniques to study plant responses to elevated carbon dioxide (CO2) concentrations. A study on the effects of CO2 enrichment on oil palm growth, physiology and yield using OTC method was conducted at the Malaysian Palm Oil Board (MPOB) Research Station in Kluang, Johor, Malaysia. Oil palm clones P164 were cultivated in four OTC each with 9 m diameter and 10 m high. The OTC consists of a concrete structure with transparent multi-wall sheets. It has a truncated top for air aversion and to prevent CO2 dilution within the chamber by outside air. The CO2 gas was injected from nozzles mounted on the inner wall. The OTC was able to maintain a higher CO2 level inside the OTC than ambient level. Air temperature inside the OTC was slightly higher than ambient, while relative humidity and photosynthetically active radiation (PAR) inside the OTC were both slightly lower than ambient. A comparison of parameters measured inside the OTC and ambient provides a measure of the chamber effects. However, it could have either positive or negative effect on plant growth. The OTC method has some limitations and is only suitable for studying individual plant physiological responses to elevated CO2.

INVASIVE RUGOSE SPIRALLING WHITEFLY Aleurodicus rugioperculatus MARTIN, A SERIOUS PEST OF OIL PALM Elaeis guineensis IN INDIA

Occurrence and severe infestation of the invasive rugose spiralling whitefly (RSW), Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae) on oil palm (Elaeis guineensis Jacq.), (Arecales: Arecaceae) in India is reported for the first time. The severity of its infestation, impact on oil palm cultivation, occurrence of natural enemies and non-chemical management strategies against RSW are discussed.

ENERGY CONSUMPTION DURING TRANSPORTATION ALONG THE PALM OIL SUPPLY CHAIN IN MALAYSIA

The Life Cycle Inventory (LCI) analysis on the energy consumption was based on the study of the transportation of palm oil (PO), refined, bleached and deodourised (RBD) palm olein (POo) and palm stearin (POs) throughout the PO supply chain beginning from the transportation of the oil palm pollinated bunches from the ‘mother palm’ to the transportation of the RBD PO and its fractionated products, namely RBD POo and RBD POs from refineries/fractionation plants to the ports and finally to the retailers. The LCI analysis found that based on the production of 1 t RBD PO, the transportation of fresh fruit bunches (FFB) from plantations to mills consumed the highest energy followed by the transportation of POo from refineries to retailers and the transportation of crude palm oil (CPO) from PO mills to refineries, while the transportation of pollinated fruit bunches, germinated seeds and seedlings consumed the least amount of energy. The energy consumption on the basis of the production of 1 t RBD PO for the transportation of FFB from plantations to mills, RBD POo from refineries to retailers and CPO from mills to refineries were 197.12 MJ, 192.78 MJ and 151.50 MJ, respectively. Based on the actual production of the materials transported on an annual basis, it was estimated that the transportation of RBD PO, RBD POo and RBD POs along the palm oil supply chain consumed 7.025 billion MJ (0.168 Mtoe) energy per year.

DEVELOPMENT OF ANALYTICAL METHOD FOR DETERMINATION OF THIOSULTAP-DISODIUM RESIDUE IN PALM OIL MATRIX

Thiosultap-disodium (thiosultap) has been identified to be the potential alternative to monocrotophos and methamidophos for controlling bagworms and leaf earting caterpillars infestation in oil palm plantations. This article reports a simple and fast method of determining thiosultap residue in palm oil matrix using liquid chromatography coupled to a triple quadrupole mass spectrometer. The proposed method has been inhouse validated . Method recoveries were found to be satisfactory within the range of 72% to 103%, method precision was good with a relative standard deviation (RSD) of 4% to 6% for repeatability and RSD of less than 12% for intermediate precision. Method limit of detection and determination were estimated from matrix matched calibration curves, the values were 2.9 ng ml-1 and 8.7 ng ml-1, respectively. The fact that no maximum residue limit has been set for thiosultap in palm oil internationally, suggesting that the default value of 0.01 mg kg-1 maximum allowable limit is to be enforced. An analytical method that will enable the determination of thiosultap residue at this default level therefore is required to facilitate the monitoring of potential thiosultap residue contamination in palm oil traded in Malaysia.

SYNTHESIS OF GLYCEROL TRILEVULINATE ESTER: EFFECT OF REACTION PARAMETERS

Derivatisation of glycerol (Gly) with levulinic acid (LA) to produce glycerol trilevulinate (Gt-LE) was studied. The reaction parameters affecting synthesis of Gt-LE were investigated. Catalytic and non-catalytic reactions between Gly and LA were carried out. Effects of reaction time and temperature on non-catalytic reaction were observed. Conversely, for catalysed reaction, reaction parameters studied were type of catalyst, mole ratio, catalyst loading and reaction time. Result analysis indicated that for the catalyst-free reaction, increment of reaction time and temperature will further reduce the acid value of reaction product. On the other hand, for catalytic reaction, p-TsOH accelerated the reaction much faster than montmorillonite, Amberlyst-15 or Amberlyst-46. Result analysis also showed that the best mole ratio and catalyst loading to obtain high composition of Gt-LE without having to go through cumbersome purifying process was 1:6 with 8% catalyst loading. For reaction conducted with mole ratio of 1:6 (Gly:LA), the optimum reaction time and temperature was found to be 8 hr and 140°C, respectively, in which GC analysis showed that product contained about 84.5% of Gt-LE.

CRUDE GLYCEROL UTILISATION IN MONOLAURIN PRODUCTION USING IMMOBILISED Rhizomucor miehei LIPASE: OPTIMISATION AND THERMODYNAMICS STUDY

The significant growth of biodiesel industry causes an excessive production of crude glycerol in Malaysia’s market, especially being as one of the global biggest producers and exporters of palm oil. The ability of crude glycerol being reused as a substrate to produce monolaurin has been the main focus while catalysing the production efficiency using Lipozyme RM IM, a commercial immobilised Rhizomucor miehei lipase in a solvent-free system. Optimal reaction conditions obtained were 8:1 molar ratio of crude glycerol to lauric acid, temperature 47°C, and lipase loading 1 wt% of lauric acid. Over 82% lauric acid conversion with 56 mol% monolaurin yields was achieved within 8 hr. Using Arrhenius equation and transition-state theory, thermodynamic studies on monolaurin synthesis under the optimum conditions were performed. Energy of activation (Ea) and energy of deactivation (Ed) were found to be 89.5 kJ mol-1 and 110.7 kJ mol-1, respectively, suggesting that higher energy was required for enzyme irreversible denaturation to occur. Values of enthalpy (86.90 ≤ ΔH ≤ 86.84 kJ mol-¹), entropy (0.29 ≤ ΔS ≤ 0.28 kJ molK-¹), and Gibbs free energy (-2.53 ≤ ΔG ≤ -5.22 kJ mol-¹) of the esterification were also determined.

SIGNIFICANT QUALITY OF FRAGMENTED FORESTS IN OIL PALM PLANTATIONS: LESSON FROM THE ASSEMBLAGE STRUCTURE OF FROGS (Amphibia: Anura)

Being known as a good environmental indicator, the anuran is an ideal animal model for investigating the quality of High Conservation Value (HCV) areas (fragmented forests) in maintaining or enhancing biodiversity values in an oil palm plantation. Using non-metric multidimensional scaling (NMDS) frogs from forest fragments and oil palm were investigated and compared, to identify species assemblages and guild. Our findings showed that species diversity differed significantly between High Conservation Values and the plantation areas. The High Conservation Value showed highest percentage of species endemism, and species of conservation importance in the areas. The NMDS analysis further suggests that the anuran assemblages at the oil palm plantation were disjunctive as the HCV areas provide isolated assemblages to the anuran species, different from that of the plantations. The number of species was found to be significantly influenced by water temperature, turbidity, salinity, and level of dissolved oxygen. Overall, the HCV areas supports high species diversity, including endemic and near threatened species compared to the plantation areas. Hence, these HCV areas are functioning and should be maintained as high priority areas for faunal conservation in an oil palm plantation.

THE POTENTIAL OF ENDOPHYTIC Trichoderma FROM OIL PALM (Elaeis guineensis Jacq.) ROOTS OF NORTH SUMATRA, INDONESIA AGAINST Ganoderma boninense

Utilisation of endophytic Trichoderma increases tremendously as an alternative control against G. boninense, causal pathogen of basal stem rot (BSR) disease of oil palm. However, investigation of endophytic Trichoderma from Indonesia is still very scarce. The aims of this study were to isolate, identify and investigate the potential of endophytic Trichoderma from oil palm roots. Three potential endophytic Trichoderma species were isolated and further identified using macroscopic, microscopic, and molecular methods. Antagonistic activities of endophytic Trichoderma were tested using dual culture agar and poison food agar assay. A molecular approach using DNA sequencing of 5.8S-ITS region successfully identified the endophytic Trichoderma isolate ET501 as Trichoderma reesei strain RHa, while isolates of endophytic ET523 and ET537 were identified as Trichoderma asperellum isolate F1 and Trichoderma asperellum strain Q1, respectively. Trichoderma reesei ET501 was the most aggressive isolate against G. boninense with PIRG of 95.1% compared to T. asperellum ET523 and T. asperellum ET537 with PIRG of 87.1% and 88.9%, respectively. Meanwhile, T. reesei ET501 showed the strongest antibiosis activity with 100% inhibition in 80% concentration, compared to T. asperellum ET523 and T. asperellum ET537 which gave 12.3% and 90.5% of inhibition, respectively.

EFFECT OF BIOFERTILISER CONTAINING DIFFERENT PERCENTAGE RATES OF CHEMICAL FERTILISER ON OIL PALM SEEDLINGS

Extensive use of inorganic substances contained in chemical fertilisers leads to environmental pollution and makes the plant more susceptible to diseases. The utilisation of beneficial microbes in biofertilisers has become a key solution in reducing the usage amount of chemical fertilisers in agriculture. This study was conducted on oil palm seedlings (OPS) in a nursery and treated with biofertiliser with zero chemicals (BF0), biofertiliser containing two percentage levels of chemical fertiliser (CF) (BF + 40% CF and BF + 50% CF) and two controls consisting of 100% chemical (CF100) and standard organic (SO) fertiliser. The vegetative measurements and foliar nutrients analysis for the OPS were recorded three and five months after fertilisation (MAF), when the OPS were six and eight months old, respectively. The application of biofertilisers containing low CF rates resulted in higher vegetative measurements compared to application of 100% chemical. Nutrients analysis showed that application of biofertiliser assisted in the increase of essential nutrients uptake in the OPS. Thus, we concluded that combination of biofertiliser with small rates of chemical able to increase vegetative measurements and nutrients uptake. Biofertiliser application is also capable in reducing the sole use of 100% chemical fertilisers, which is non environmental-friendly and expensive.

INDUCED SYSTEMIC RESISTANCE AND PROMOTION OF PLANT GROWTH IN OIL PALM SEEDLINGS BY ENDOPHYTIC Trichoderma virens

Trichoderma spp. have been widely used as a biological control agent for plant disease including basal stem rot (BSR) in oil palm. Trichoderma spp. control pathogens through mycoparasitism, antibiosis and triggering induced systemic resistance (ISR) in plants during the colonisation of plant roots, limiting the manifestation of the pathogenic fungi. In this study, we investigated the role of endophytic Trichoderma virens as a plant-growth promoter and its ability to prime the immune system of the host through ISR in oil palm. Mixed application of two endophytic isolates of T. virens 7b and 159c was found to significantly enhance the growth and development of oil palm seedlings, in terms of height, girth and chlorophyll content compared to individual treatment. However, results showed that individual treatment of 7b and 159c was better in lignin biosynthesis. Plant defence-related enzyme activities; peroxidase, polyphenol oxidase, superoxide dismutase and phenylalanine lyase were prominently elevated in the leaves of oil palm seedlings upon treatment of the respective T. virens isolates via plant roots. This study demonstrated the triggering of ISR in oil palm seedlings via T. virens treatment and proving that the inoculation of T. virens isolates 7b and 159c were able to promote the vegetative growth and development of oil palm seedlings.

SureSawitTM TRUE-TO-TYPE – A HIGH THROUGHPUT UNIVERSAL SINGLE NUCLEOTIDE POLYMORPHISM PANEL FOR DNA FINGERPRINTING, PURITY TESTING AND ORIGIN VERIFICATION IN OIL PALM

A high performing True-to-Type single nucleotide polymorphism assay, consisting of a minimal set of single nucleotide polymorphism markers was developed for oil palm. The single nucleotide polymorphism panel was developed from a range of diverse materials consisting of germplasm and advanced breeding lines. Analyses demonstrated that the single nucleotide polymorphism panel is effective at uniquely finger printing and discriminating individual palms from unrelated pedigrees. In addition, the single nucleotide polymorphism panel is a very useful tool in breeding programmes, as it can effectively discriminate between individual progeny in half-sibling, full sibling and selfed crosses. Furthermore, illegitimate palms present in half-sibling, full sibling and selfed crosses are easily identified. The single nucleotide polymorphism panel is an excellent quality control tool for use in tissue culture, as clonal materials could be differentiated based on their lineage. The fact that ramets of different clonal lines were easily distinguished, indicates that it will also be an excellent tool to identify potential culture mix-ups that occur either in the laboratory, nursery or during field planting.

DETERMINATION OF REFERENCE GENES FOR NORMALISATION OF GENE EXPRESSION STUDY OF Ganoderma-INFECTED OIL PALMS

Basal stem rot (BSR) disease is a major threat to oil palm industry in Malaysia, caused by pathogenic fungus, Ganoderma boninense. Quantitative real-time polymerase chain reaction (qPCR) has become a favourable method in quantification the levels of gene expression involved in disease development. In this study, 14 oil palm reference genes were tested for their suitability as reference genes for qPCR analyses using oil palm root taken from six-month old seedlings (nursery sample) and 15-year old mature palms (field sample). Only six reference genes were subjected to stability test via RefFinder. The GRAS and ACTIN genes were ranked as the best reference genes for nursery sample, whereas, GAPDH and GvHK genes for field samples. These reference genes were used in the qPCR analysis for accurate normalisation. Thus, results obtained in this study emphasise the importance of validating the stability of the reference gene and proving the credibility and reliability of RefFinder in determining the most stable reference genes in each specific experiment or biological setting used.

IDENTIFICATION OF GENES PREFERENTIALLY EXPRESSED IN MESOCARP TISSUE OF OIL PALM USING in silico ANALYSIS OF TRANSCRIPTS

Strong demand for palm oil creates a huge challenge for the industry to produce more palm oil on the shrinking cultivable land mass. Genetic manipulation of oil synthesis in the mesocarp tissue of oil palm offers the opportunity to improve yield and quality of palm oil on the limited land resources. However, more than one mesocarp-specific promoters are required to effectively manipulate oil synthesis to avoid epigenetic silencing caused by the sequence homology in their promoter regions. This study was aimed at identifying genes that are specifically expressed in the mesocarp tissue through in silico analysis of transcriptome datasets from different oil palm tissues. From this analysis, transcripts XLOC_10, annotated as pentatricopeptide repeat (PPR) protein was highly expressed in the mesocarp tissue. Gene expression analysis of PPR in 27 tissues of Elaeis guineensis indicated that this putative mesocarp-specific transcript was expressed in mesocarp and female inflorescence tissues only. Cis-acting elements that are present in the promoter region of PPR showed that PPR might be involved in the lipid biosynthesis and flowering regulation network in oil palm.

A REVIEW OF DEVELOPMENTS IN INTEGRATED PEST MANAGEMENT (IPM) OF BAGWORM (Lepidoptera: Psychidae) INFESTATION IN OIL PALMS IN MALAYSIA

Severe and unprecedented outbreaks of bagworms and nettle caterpillars occurred on oil palm plantations in the Malaya in late 1950s to early 1960s, caused by applications of organochlorine insecticides, which killed insect natural enemies more effectively than they did the pests. Outbreaks mostly declined when applications ceased, sometimes with resurgence because the pesticides also upset the co-ordination of pest and enemy life cycles. Selective pesticides were found (‘integrated control’), and there was general freedom from serious outbreak until around 1990. Incidence, particularly of bagworms, then again became common, with parallel increase in pesticide use. A range of investigations have progressed over the years. During the 1960s, clean weeding had been indicated as conducive to caterpillar pest outbreak by removing shelter and floral food of the natural enemies. Field trials have shown that several beneficial plant species could extend the life of parasitoids, and where planted, bagworm numbers declined whilst natural enemy numbers relatively increased. On-going studies screened additional chemicals mostly emphasising selective potential through stomach action and specific lethality to caterpillars. Microbial pathogens were sought in the field for testing on bagworms by applying suspensions of ground up cadavers, as proven effective for nettle caterpillars. Strong attraction of male bagworms to a female pheromone was demonstrated, suggesting promise of a practical trapping technique. Predators such as Sycanus dichotomus build up in high caterpillar populations, indicating potential of rearing for mass field release to quickly reduce outbreaks. All of these methods could aid in restoring and maintaining subeconomic levels of leaf-eating caterpillars in a balanced and sustainable agroecosystem.