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VOLUME 9 NO. 2

IDENTIFICATION OF PALM OIL AND ITS FRACTIONS BY HPLC USING TRIACYLGLYCEROL PEAK-AREA RATIOS

Halimah Bt. Muhamad, Kurt Aitzetmuller, Gisela Werner, Margaretha Gronheim And Siew Wai Lin

The concept of peak-area ratios in reversed-phase HPLC of triacylglycerols in palm oil and palm oil fractions was expanded and tested by analysis of numerous authentic samples. Palm oil fractionation changes the tripalmitin and triolein peaks and peak area ratios. To expand the data base, a large number of palm oils, palm oleins and palm stearins of Malaysian origin were investigated and the results compiled. Variability of the peak areas and peak area ratios with changes of solvents is discussed. Peak area ratios were found to be useful in identifying palm oils from different sources as well as in detecting possible admixtures of oils.

SYNTHESIS AND CHARACTERIZATION OF THE MONOETHANOLAMIDE FROM PALM OIL

K. Dzulkefly, S. Hamdan, D. Zaizi, K. Anuar And M. Badri

Palm monoethanolamide (PMEA) was synthesized by direct transamidation of palm oil with monoethanolamine at temperatures between 80-160° C. The maximum yield (85-5%) was achieved at a palm oil/monoethanolamine mole ratio of 1:3, temperature of 160°C, reaction time of three hours and catalyst concentration of 0.6%. Recrystallization using a combination of hot hexane and warm water were the best conditions to purify the PMEA, as judged by its melting point and infrared (IR) spectrum. The PMEA was not soluble in water and most hydrocarbon solvents. However, about 60% of it dissolved in a microemulsion system containing 25% water at 50°C. the transamidation process proceeded via a first order reaction with an activation energy of 17.4kJ/mol.

ANALYSIS OF OIL PALM PRODUCTIVITY
1. THE ESTIMATION OF SEASONAL TRENDS IN BUNCH DRY MATTER PRODUCTION

I.E. Henson

When assessing oil palm productivity over periods of less than a year, the direct use of bunch harvest data, normally available as monthly totals of FFB yield, is inadequate as much of the dry matter in a bunch may be formed prior to the month of harvest. Also, as is widely recognized, the higher energy content of bunches compared with vegetative tissue needs to be allowed for. To take account of these factors, a simple model was constructed based on monthly FFB yields, final bunch composition, growth curves of bunch components and component energy contents, to allow the bunch 'non-oil equivalent' dry matter production (BDMP*) achieved each month to be calculated.

The model was applied to data from two sites over several seasons. BDMP* estimates from the model showed similar, but displaced, cyclic patterns to FFB, and gave smoother curves with lower CVs. Although based on a fixed bunch growth rate throughout the year, the results proved insensitive to growth duration and were similar for growth periods ranging from 130 to 190 days.

ANALYSIS OF OIL PALM PRODUCTIVITY. II. BIOMASS, DISTRIBUTION, PRODUCTIVITY AND TURNOVER OF THE ROOT SYSTEM

I.E. Henson And S.H.Chai

As part of a programme investigating the productivity of oils palms in West Malaysia, measurements were made of root standing biomass in two successive years at each of six sites. Palms at the first two sites were sampled three and four years after planting and the others at nine and ten years. One site was on a 'coastal' soil while the others were on 'inland' soils of various series. In two cases, direct comparisons were made of adjacent 'wet' and 'dry' areas. One each site detailed measurements were also made of above-ground standing biomass and productivity.

On each site root-free soils cores were 'installed' and sampled for roots after a six month period, allowing an assessment of new root production and providing a measure of root biomass turnover. An alternative estimate of turnover was obtained for the coastal site using a carbon balance approach.

Ratios between root:shoot standing biomass and the proportion of total assimilates allocated to the shoot versus the root system are presented for each site.

Results are discussed in relation to those of other studies of oil palm root biomass.

PROLINE ACCUMULATION IN THE LEAVES OF WATER STRESSED OIL PALM (Elaeis guineensis Jacq.) SEEDLINGS

Mohd. Haniff Harun

An increase in stomatal resistances of oil palm seedlings was realated to increasing water deficit indicated by a reduction in leaf water potential. Proline began to accumulate after stomatal resistance reached a peak (215.6±16.8 s.cm-1). This led to a recovery in leaf water potential followed by a similar reduction in stomatal resistance. The proline level eventually fell to the control after watering was resumed. Water stress was also found to reduce dry matter production and its partitioning to the root system of oil palm seedlings.

PREPARATION OF BIODEGRADABLE AND VEGETABLE BASED SURFACTANT FROM SUGAR AND PALM FATTY ACID CATALYZED BY Mucor miehei LIPASE

Rakmi Abdul Rahman, Tjahjono Herawan And Othman Omar

Sugar ester was prepared from palm fatty acid distillate (PFAD) with Lipozyme IM (immobilized Mucor miehei) as catalyst. Four sugars were used sucrose, sucrose octaacetate, glucose and fructose. Fructose was esterified by PFAD to produce 17.70 mg/ml solvent of product while glucose produced 13mg/ml solvent. It was found that a mol ratio of fructose /PFAD of 1/10, 10% lipase concentration and a temperature of 55°C gave the highest yield. Analyses of its physical and chemical properties showed that fructose ester had a melting point of 49°C - 52.3°C. The surfactant, a fructose ester, also reduced the surface tension of water from 74dyne/cm to 38.3dyne/cm.

Even though the yield was still quite low compared to what had previously been obtained using other substrates, this study showed that enzymatic preparation of surfactant from PFAD is possible.

VOLUME 9 NO. 1

ROLE AND EFFECTIVENESS OF Elaeidobius kamerunicus, Thrips hawaiiensis AND Pyroderces sp. IN POLLINATION OF MATURE OIL PALM IN PENINSULAR MALAYSIA

Mohd Basri Wahid and Norman Hj. Kamarudin

A study on the pollination of seven-year old palms in a plantation in Selangor, Malaysia was made between 1983 and 1987 to determine the relative roles of three types of pollinators, Elaeidobius kamerunicus (Coleoptera: Curculionidae), Thrips hawaiiensis (Thysanoptera) and Pyroderces sp. (Lepidoptera: Cosmopterygidae) as well as to examine their effects on oil palm bunches. Samples were collected monthly from anthesising male inflorescences to provide information on the actual and potential populations of pollinators. The activities of pollinators on anthesising female inflorescences were measured by pan-trapping. All anthesising female inflorescences at the time of population sampling were marked and the fruit bunches which formed were later harvested for analysis. The weevil Elaeidobius kamerunicus had not displaced T. hawaiiensis and Pyroderces sp. as was evident from their co-existence. Their pollination activities had sustained the fruit set and fruit to bunch ratios above 60 per cent. Nevertheless, E. kamerunicus had become the most important pollinator, even during the wet season. During dry periods, T. hawaiiensis played a more important role than E. kamerunicus in pollination. The critical threshold of weevil numbers required for pollination could not be determined because the fruit set had not declined to low levels. Furthermore, a high population was not necessarily beneficial because it resulted in the lowering of fruit set. During the period after the introduction of the weevil into Malaysia, there was no significant change on bunch parameters, with one exception: oil to bunch ratio showed a marked depression in 1985, three years after the introduction of the weevil. Three explanations have been suggested, the most important of which was related to a marked increase in the moisture content of the fruit bunches.

EFFECT OF FIRST STAGE DRY FRACTIONATION ON THE QUALITY OF CBE BASED ON PALM OIL AND SAL FAT

Md. Ali, A.R., Tan, S.Y., and Azman, K.

Palm oil (PO) and sal fat (SL) were dry fractionated separately at 30-33^oC to remove the high melting constituents, yielding palm olein (POo), and sal olein (SLo). Acetone fractionation was then conducted on a blend of POo+SL((7:3) to produce CBE1, and on a blend of POo+SLo(7:3) to produce CBE2. Changes in the composition of the fractionated products were monitored from the triacylglycerol profiles and polar lipid content, while physical changes were observed from the DSC melting profile and Jensen cooling curve. The dry fractionation reduced the trisaturated triacylglycerol content of palm oil, but had no profound effect on the triacylglycerol composition of sal fat. Nevertheless, dry fractionation reduced the polar constituents of sal fat, and improved the physical characteristics of the CBE produced.

DETERMINATION OF ANTIOXIDANTS IN PALM OIL PRODUCTS BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

Razali, I., Norhaya, H. and Nor Asimah, A.S.

Tertiary butyl hydroquinone (TBHQ), butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) were found to be the common antioxidants used in the palm oil industry. They are added to palm oil products either singly or in combination within the permissible limit of 200 parts per million. A procedure for the determination of the phenolic antioxidants which is based on the AIIBP method using a single step methanolic extraction and reverse phase gradient elution by HPLC was proven to be very simple and reliable.

A LOCAL Bacillus thuringiensis, SRBT1 WITH POTENTIAL FOR CONTROLLING Metisa plana (WLK).

A.S. Ramlah Ali and W. Mohd Basri

Most commercial products from Bacillus thuringiensis (B.t.) were ineffective for controlling Metisa plana (Wlk.). The effectiveness of a B.t. product against an insect depends on its protoxin composition, and the presence of suitable receptor sites and factors activating the toxic crystals within the insect's midgut. The pH of the midgut must be suitable for solubilizing crystals prior to activation. The selection of a B.t. strain effective against the target pest is a practical approach. A B.t. strain containing the right toxin which binds to receptors sites present in the pest needs to be identified and selected by screening. This paper reports on the progress made in increasing the potency of a local strain of B.t., SRBT1, selected after a study of its toxicity. Alkaline and acidic compounds were added to SRBT1 to enhance the effect of its toxins. The addition of 0.5% tannic acid and 1.5% sodium borate showed a 4-fold increase in mortality of M. plana at 4 days after treatment (DAT). A three fold increase in mortality resulted from incorporation of 0.5% magnesium chloride and a two fold increase with 0.5% potassium carbonate and 0.5% sodium borate at 4 DAT. At 6 DAT, SRBT1 containing 1.5% sodium borate caused 94% mortality, as against 70% for the best commercial product tested, Florbac. One hundred percent mortality was observed at 9 DAT when 0.5% sodium borate, 0.5% and 1.5% tannic acid were added separately to SRBTI. SRBTI with no chemical additive produced 100% mortality at 11 DAT. SRBT1 with or without chemical additives, gave a marked reduction, 98 - 100%, in leaf area damaged (LAD) as compared with the control. This reduction is comparable to that produced by methamidophos 99.4%. Florbac gave only 59.7% reduction in LAD. The reduction in LAD was more obvious when sodium borate and tannic acid were used. SRBT1 must harbous toxins suitable for the control of M. plana, because the effect on feeding behaviour is very pronounced. Determination of SRBT1 cry genes, cry proteins and exploitation of this isolate should be attempted.

STABILITY OF EMULSIONS OF REFINED PALM OIL AND ITS LOW MELTING POINT FRACTION WITH EGG PHOSPHOLIPID

Dzulkefly, K., Hamdan, S., Zaizi, M. D., Ahmad, F.B.H. And Anuar, K.

Emulsions of high melting point refined, bleached and deodorized palm oil (PO36) and its low melting point fraction (PO15) were prepared using egg yolk phospholipid. Their stability after 24 hr storage were compared to that of soybean oil. The low melting point palm oil fraction (PO15) formed stable emulsions similar to that of soybean oil.However, emulsions of the high melting point refined palm oil (PO36) were unstable and phase separation occurred immediately.