Category Archives: 2009 Vol 21 June

Laboratory-scale pyrolysis of oil palm pressed fruit fibres

The slow pyrolysis of oil palm pressed fruit fibres (PFF) was investigated in a laboratory-scale pyrolyser atterminal temperatures of 450°C to 800°C and a heating rate of 10°C min-1. The PFF was first pyrolysed in a thermogravimetric analyser (TGA) to investigate their thermal characteristics and to determine their kinetic parameters. Results from the laboratory-scale pyrolysis showed that as the terminal temperature increased, the yields of solid char and total condensates decreased, but the non-condensable gases increased. The quality of the char produced, which was found to be dependent on the terminal pyrolysis temperature, was of medium grade, as its average ash content of 16.60% was high. The best PFF char with 69.91% fixed carbon and an energy content of 27.07 MJ kg-1 was obtainable at a terminal pyrolysis temperature of 600°C. The chemical characterization of the liquid products, which separate into two fractions, showed that they may be a potential source of valuable fuel and chemical feedstocks.

Plant carotenoids: molecular genetics and regulation

The potential health benefits of carotenoids as anti-cancer and antioxidant agents have recently been demonstrated. In particular, lycopene and β-carotene have lately been shown to be able to reduce the risk of chronic conditions of coronary heart disease, certain cancers and macular degeneration. The findings have led to rapid development in the field aimed at understanding the biosynthetic pathway and ultimately engineering the carotenoid content. This article reviews the recent progress made in the areas of molecular genetics and genetic engineering of plant carotenoids. The latest development in the regulatory mechanisms controlling the pathway is also highlighted. Finally, this review also highlights some recent progress made in oil palm carotenoid research, especially the molecular cloning of genes encoding key enzymes of the biosynthetic pathway and efforts to improve oil palm carotenoid content.

Pathogenicity of granule formulations of Metarhizium anisopliae against the larvae of the oil palm rhinoceros beetle, Oryctes rhinoceros (L.)

Granule formulations consisting of mycelia and spores of Metarhizium anisopliae var. major as the active ingredient were produced and tested against the larvae of Oryctes rhinoceros. The effect of the medium pH on the production of mycelia was investigated, and the granule compositions were optimized. The fungus produced higher yields of mycelial pellets (0.58 g) at pH=8 as compared to pH=5, 6 or 7. Granules prepared from mycelia with the growing medium (G+MM) improved fungal growth (100%) and sporulation (87.2%) as compared to granules prepared from the mycelia alone (G+M) (growth and sporulation, 62.4% and 47.6%, respectively). The amounts of ingredients, such as kaolin and rice bran used in making the granules, were then optimized. The weight of granules increased as the amount of kaolin and rice bran increased, but granule quality was reduced. The highest quality granules (with growth 98.5%, sporulation 88.6% and dry weight 1249 g) were prepared with 925 g kaolin and 400 g rice bran. The pathogenicity of the G+MM granules was tested against the third instar larvae of O. rhinoceros. The test showed that at 20 days after treatment (DAT), treatment with rates of 1.0 g and 2.0 g granules/box caused 90% mortality, which was as high as with the treatment using pure spore solutions (96%). The G+MM granules produced more spores and more quickly than granules made from spores (G+Sp). Both types of granules produced 0.42-6.60 x 106 spores/granule. Results of the bioassay indicated that application of G+MM and G+Sp at rates of 3 g, 6 g and 9 g killed 100% the third instar larvae as early as at 18 DAT. Infection level increased as the application rate increased. G+MM and G+Sp applied at 9 g/box caused the highest infection of 93.3% in the larvae. The potential use of the granule formulation to control O. rhinoceros in the field was also discussed.

Solid-state characteristics of microcrystalline cellulos from oil palm empty fruit bunch fibre

Oil palm empty fruit bunches (EFB) are one of the by-products generated from palm oil mills. They consist mainly of lignocellulosic compounds, namely cellulose, hemicellulose and lignin. Cellulose, in particular, constitutes about 37% (dry weight) of the EFB, and is a compound with high value and can be exploited for the benefit of the palm oil industry.
In this study, an attempt to prepare microcrystalline cellulose (MCC) from the isolated EFB-cellulose was carried out. The MCC was prepared by controlled acid hydrolysis of the isolated a-cellulose which attacked the amorphous region, and was followed by the back neutralization process with alkali. The structural properties of the cellulose and MCC were studied by Fourier Transformed Infra-red Spectrometry (FTIR) and X-ray diffraction methods. The FTIR spectrum of MCC from EFB was identical to that of the commercial MCC as well as the cellulose which showed comparable presence of C-O-C, C-C, O-H, and C-H bands. However, a broad peak at 3329 cm-1 was observed from the EFB-cellulose due to absorption vibration of the hydroxyl groups. The X-ray diffraction pattern revealed a low degree of order for EFB-cellulose and a relatively ordered structure for EFB-MCC. Two peaks of diffraction angles ranging between 19º and 23º were observed in the EFB-MCC, indicating the presence of a small percentage of cellulose II. The commercial MCC had a highly ordered structure compared to EFB-MCC as indicated by the presence of a single peak at 22.5º.

Concentration and isolation of individual vitamin E components in palm phytonutrients concentrate using high performance liqiud chromatography with flourescence detection

Palm phytonutrients concentrate is a rich source of vitamin E. Vitamin E content in palm phytonutrients concentrate was found to be 15 370 ppm. Components of vitamin E identified in the palm phytonutrients concentrate consists of α-tocopherol (α-T), γ-tocopherol (γ-T), α-tocotrienol (α-T3), γ-tocotrienol (γ-T3) and δ-tocotrienol (δ-T3). This article reports a study on the concentration of individual palm vitamin E components in crude palm oil (CPO), palm phytonutrients concentrate (PPC) and unsaponifiables of palm phytonutrients concentrate (unsap PPC). This article also reports a study on the concentration of bulk vitamin E through the application of open column chromatography and subsequent isolation of individual palm vitamin E components using High Performance Liquid Chromatography (HPLC) with fluorescence detection and a semi-preparative silica column. As the vitamin E components are concentrated in a stepwise manner by means of saponification, open column chromatography and semi-preparative HPLC, the concentration of individual components can be enriched by up to 94.6%.

Early detection of Ganoderma causing basal stem rot disease in coconut plantations

Basal stem rot disease of coconut caused by Ganoderma lucidum (Leys) Karst is prevalent throughout the world, causing significant damage and losses to coconut plantations. The pathogen is soil-borne in nature. For early diagnosis, different techniques viz., enzyme-linked immunosorbent assay, dot immunobinding assay and polymerase chain reaction have been used in modern era of plant pathology. In this study, we have tried ELISA and DIBA using the monospecific antibodies raised against a distinct common protein with a molecular weight of 62 kDa. The protein was observed in all the isolates of Ganoderma collected throughout Tamil Nadu, India, by the sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) analysis and variations in the protein patterns were found between Ganoderma isolates. The polyclonal antisera were developed against the purified single protein of Ganoderma. The presence of the 62 kDa protein in the crude mycelial extract was confirmed by western blot analysis. Using the antisera, the pathogen was detected by Indirect ELISA and dot immuno binding assay (DIBA) which resulted in positive reactions for infected samples and negative reactions for apparently healthy palms. These serological techniques gave better results in early diagnosis of field samples, and it could be adopted for large-scale application.

Monoglycerides from 9, 10-dihydroxystearic acid for the cosmetics industry

Monoglycerides of dihydroxystearic acid (MGDHSA) were synthesized using an acid catalyst. Factors that may affect the esterification reaction such as reaction time and temperature were studied. Esterification of dihydroxystearic acid with excess glycerol by an acid catalyst at 150oC for 4 hr gave up to 40% yield of MGDHSA. The reaction product containing approximately 45% MGDHSA was found to be non-irritant to the skin, non-toxic to the aquatic environment and readily biodegradable. The toxicity value of MGDHSA was found to be more than 100 mg litre-1 while its biodegradability reached the pass level of 60% in 20 days. This compound is compatible with a wide variety of oils. MGDHSA seem to have better emulsifying properties in an oil-in-water (O/W) system with high water content compared to glyceryl monostearate (GMS) and glyceryl monohydroxystearate (MGHSA).