Category Archives: 2007 Vol 19 Dec

Flanking AFLP markers for the virescens trait in oil palm

Using the monofactorially inherited virescens trait to determine the ripeness of oil palm fruit bunches, instead of the current counting of abscissed and fallen fruits, has the potential to facilitate harvesting and milling because of the starker colour change. Virescens fruits are characterized by being distinctly emerald green when young, turning to a bright orange on ripening, whereas the presently commercially produced Nigrescens fruits are dark purple young, and red/purple ripe. AFLP markers of 142 bp and 356 bp developed from the primer combination E-ACT/M-CAT and of 254 bp from E-ACT/M-CTA were found to be closely linked to the virescens trait in two crosses. The markers that flank the virescens gene on the genetic linkage map of oil palm may be useful for marker-assisted breeding for the virescens trait

Large scale production of octyl-9,10-dihydroxystearate by immobilized lipase

Large scale production of octyl-9,10-dihydroxystearate was performed in a 5-litre batch, stirred tank reactor with a multi-bladed propeller. The effects of reaction temperature, reaction time, enzyme dosage and agitation speed were studied. The optimal conditions for the ester synthesis were reaction temperature at 50ºC, reaction time of 3 hr, catalyst concentration of 10% (w/w) and agitation speed of 300 rpm. The percentage conversion was about 90% with respect to the amount of dihydroxystearic acid (DHSA) used. The operational stability of the catalyst was also evaluated

Predicting soil water status, evapotranspiration, growth and yield of young oil palm in a seasonally dry region of Malaysia

The northern part of Kedah, Malaysia, generally experiences an annual dry season that may extend from two to three and a half months. Nevertheless, there has been increased expansion in the area of oil palm in the region. In this study, the model OPRODSIM (Oil Palm Production Simulator) was used to examine and predict responses to climatic conditions during the first six years after planting, based on daily climatic data, and to predict growth and yield for a further four years.
The mechanistic model generally confirmed measured trends in soil water status and crop water use, and effectively simulated annual bunch yields and annual changes in some vegetative parameters. It was least successful in reproducing frond production rate (FPR; mostly overestimated), frond biomass production (FBP; overestimated) and total frond number per palm (TFNP; either over- or underestimated except in the fourth year). Total vegetative standing biomass (TVSB), frond standing biomass (FSB) and trunk standing biomass (TrSB) were simulated well in years three and four but underestimated in the two subsequent years. Trends in root standing biomass were reproduced well.
Simulation of trunk biomass production (TrBP) was good, except in year six when it was underestimated. Root biomass production (RBP) was generally underestimated but simulation of total vegetative biomass production (TVBP) was generally satisfactory.
Bunch yields were well simulated, with the correspondence between mean measured and modelled yields being improved by lagging yield by two years with respect to the weather data.
These results suggest that the model provides a useful first approximation for simulating the effects of climate on yield, dry matter production, water use and soil water balance in a seasonally dry climate. However, improvements are necessary concerning the detailed simulation of vegetative growth

Palm-based estolide as an ingredient in shampoo: a preliminary study

Estolides produced from dihydroxystearic acid (DHSA-estolides) were evaluated as ingredients in shampoos. Adding DHSA-estolides to a shampoo formulation improved its detergency and combability. The compounds can also be used as a viscosity builder

Palm carotene concentrates from crude palm oil using vacuum liquid chromatography on silica gel

Palm carotene was concentrated from crude palm oil by vacuum liquid column chromatography using a commercially available adsorbent silica gel. Two products were produced, palm carotene in oil-based and carotene-depleted oil. The highest carotene concentrates (> 10%) was achieved using a ratio of 1:10 (w/w) crude palm oil:silica gel. For this ratio, activated silica gel improved the carotene recovery to 72%- 92% compared to 21% –32% by non-activated silica gel. High recovery (99%-99.5%) of the bulk oil recovered from the silica gel was achieved by elution with a polar solvent, e.g. ethanol or 2-isopropanol, followed by a non-polar solvent, e.g. hexane

Determination of benzo(a)pyrene in vegetable oils

Determination of benzo(a)pyrene in vegetable oils was carried out using aluminium oxide for clean-up followed by reverse phase high performance liquid chromatographic (HPLC). A quantity of oil was dissolved in petroleum ether and added to an aluminium oxide column which retained the lipids. Benzo(a)pyrene in the oil was eluted from the column with petroleum ether and the collected eluate was concentrated by evaporation of the solvent. Identification and quantification was performed by HPLC using fluorescence detection at the optimized wavelength. The retention time of a benzo(a)pyrene standard was used for identification and the concentration was calculated by external calibration.
The method was tested on an oil matrix, then validated by determining the recoveries of benzo(a)pyrene from vegetable oil samples spiked with polycyclic aromatic hydrocarbons at 0.01 µg kg-1 to 0.5 µg kg-1. Recoveries and coefficients of variation for the oils spiked with benzo(a)pyrene standard were 90% to 102% and 1.23%-2.03% respectively. This method was then used for monitoring the level of benzo(a)pyrene in vegetable oils.

Development of the MPOB Fast Transfer Technique (MoFaTT) system for maintenance and maturation of oil palm culture aggregates

The MPOB Fast Transfer Technique (MoFaTT) in Liquid Culture System was developed as a rapid and convenient method for liquid media replenishment during maintenance and maturation of cultures. The system was developed with the aim to further improve the efficiency of the liquid culture system. Oil palm cultures can be maintained for three to four months, and replenishment of medium can be done on the shaker at any desired time. The usefulness of the MoFaTT is not just the rate of multiplication or proliferation of cultures but also the efficiency of the system compared to the conventional maintenance of cultures in individual shake flasks. Some of the benefits offered are a reduction in medium replenishment steps and the time consumed, on-site medium replenishment and improved practicality of the system

Field evaluation of palm-based emulsions in water (ew)-insecticide formulations against insect pests on longbean and cabbage

The performance of palm-based emulsions in water (EW)-insecticide formulations was evaluated in the field against insect pests on longbean and cabbage. The insecticides used were deltamethrin and lambda-cyhalothrin. Phytotoxicity symptoms were also not observed on the treated crops.
Statistical analyses (DMRT, P<0.05) on differences between treatments indicated that the palm EW-formulations were equally effective or significantly better than the commercial EC-formulations in controlling the pests on longbean and cabbage crops. Higher cabbage yields were observed using the commercial EC-formulations [2.8% a.i. (w/w) deltamethrin and 2.5% a.i. (w/w) lambda-cyhalothrin] and two palm EW-formulations [2.5% a.i. (w/w] lambda-cyhalothrin at the recommended and lower dosage (10 and 7.5 ml/10 litre, respectively), followed by the other two palm EW-formulations [2.8% a.i. (w/w) deltamethrin at the recommended and lower rate].
The untreated plots gave the highest number of fruit damage in longbean and the highest number of multiple heads (i.e., no yield) in cabbage when compared to the treated plots. In addition, no phytotoxicity symptom was observed in both the bean and cabbage crops, meaning that the crops showed good tolerance to all the treatments.