Felled Oil Palm Research Articles

Biovalorizing felled oil palm trunk as a sole feedstock for lactic acid production through efficient simultaneous saccharification and fermentation

This study aimed to develop practical biorefinery process for bio-valorizing felled oil palm trunk (OPT) as a sole feedstock for lactic acid (LA) production. OPT was separated into oil palm sap (OPS), vascular bundle (OPT-VB), and parenchyma (OPT-PA) fractions. OPS containing high amounts of sugars (38.69 g/L) and nitrogen (0.63 g/L), could be used directly for LA production by Lactobacillus acidophilus and also as base medium for simultaneous saccharification and fermentation (SSF) of OTP-VB and OPT-PA. The repeated SSF efficiently utilized cellulosic OPT-VB and produced LA up to 50–71 g/L during five cycles. Due to high water-absorbing and swelling properties of OPT-PA, it could not be initially added at high loadings. It was then intermittently added through fed-batch SSF, which effectively produced LA of 72.85 ± 1.61 g/L. These strategies have shown the efficient biorefinery process for biovalorization of OPT and may also be applicable to other similar agricultural wastes.

Efficient Biovalorization of Oil Palm Trunk Waste as a Low-Cost Nutrient Source for Bioethanol Production

This study aimed to efficiently utilize felled oil palm trunk (OPT) for bioethanol and lactic acid production. OPT was separated into two fractions: oil palm sap (OPS) and OPT fiber. OPS contained substantial amounts of sugars (38–40 g/L) and nitrogen (0.60–0.70 g/L), which can serve as a base medium for bioethanol production. As bioethanol production requires high sugar concentrations, OPS was concentrated, supplemented with OPT fiber, and used for bioethanol production through simultaneous saccharification and fermentation (SSF) by Saccharomyces cerevisiae. Repeated-batch SSF for five cycles efficiently utilized OPT fiber and achieved an average ethanol production of 35–42 g/L in each cycle. To increase the accessibility of the enzyme, OPT fiber was acid-pretreated prior to the SSF process. The combined use of acid-pretreated OPT slurry and concentrated OPS provided the maximum ethanol production of 49.63 ± 1.05 g/L. The fermented broth after ethanol recovery, containing mainly xylose, was used to produce lactic acid at a concentration of 18.85 ± 0.55 g/L. These strategies can greatly contribute to the zero-waste biorefinery of OPT and may also be applicable for the efficient biovalorization of other similar agricultural wastes.

Oil palm trunk waste: Environmental impacts and management strategies

The replantation of oil palm in plantations occurs once in every 25 years. Felled oil palm trunk (OPT) is among the most abundant biomass left to decompose naturally in the oil palm plantations. Conversion of this waste biomass can contribute to the booming of secondary industries, which in turn opens up new job opportunities for the local communities. At present, however, OPT is predominantly left in oil palm plantations for soil enrichment purposes. This review aims to discuss the management of OPT waste to ensure the sustainability of oil palm plantations. The OPT has a unique chemical composition with high amounts of carbohydrates and moisture that enhances microbial degradation to release micro and macro nutrients into the soil. Pulverizing and windrowing partially decomposed OPT can help to increase the degradation of OPT. Apart from providing nutrients to the newly planted oil palm seedlings, felled OPT also serves as a breeding ground for pests due to the high carbon to nitrogen ratio which reduces the OPT decomposition rate. As a consequence, disease incidences and severity have been increasing drastically in consecutive replantation. Meanwhile, the removal of felled OPT from the plantation could cause nutrient depletion in the soil and increase fertilizer cost. Therefore, considerable attention from the scientific communities as well the authorities should be given to the management of felled OPT to ensure the sustainable production of oil palm. • Felled OPT is one of the most abundant biomass in oil palm plantations. • Conversion of OPT to value-added products may promote secondary industries. • Felled OPT may be a breeding ground for pests due to high carbon to nitrogen ratio. • Removal of felled OPT from plantation cause nutrient depletion in the soil.

Lipid production by Lipomyces starkeyi using sap squeezed from felled old oil palm trunks

The ability of oleaginous yeast Lipomyces starkeyi to efficiently produce lipids when cultivated on sap extracted from felled oil palm trunk (OPT) as a novel inexpensive renewable carbon source was evaluated. OPT sap was found to contain approximately 98g/L glucose and 32g/L fructose. Batch fermentations were performed using three different OPT sap medium conditions: regular sap, enriched sap, and enriched sap at pH 5.0. Under all sap medium conditions, the cell biomass and lipid production achieved were approximately 30g/L and 60% (w/w), respectively. L.starkeyi tolerated acidified medium (initial pH ≈ 3) and produced considerable amounts of ethanol as well as xylitol as by-products. The fatty acid profile of L.starkeyi was remarkably similar to that of palm oil, one of the most common vegetable oil feedstock used in biodiesel production with oleic acid as the major fatty acid followed by palmitic, stearic and linoleic acids.

Características de los troncos de palma aceitera para la crianza de Rhynchophorus palmarum (Coleoptera: Curculionidae) en la Amazonía peruana

Introduction: In the Peruvian Amazon, felled oil palm (Elaeis guineensis Jacq.) trunks are usually burned to prevent the increase of these residues. These trunks are also used for the rearing of Rhynchophorus palmarum (Linnaeus, 1758) Csiki E., 1936 larvae, which locals use as a food source. Objective: To establish the relationship between the characteristics of the cut E. guineensis trunks and the rearing of R. palmarum larvae. Materials and methods: The research was conducted in three districts (San Pedro-Campo Verde, Tahuayo-Neshuya and Maronal-Curimana) of the department of Ucayali, Peru. The correlation between the number of R. palmarum larvae and the length and diameter of the trunk’s central cylinder was analyzed using the Spearman coefficient (rs ). In addition, the soil texture class was determined and the correlation with the number of larvae was established. Results and discussion: The length and diameter of the felled oil palm trunks were different (P < 0.05) in the three sites evaluated. There is no relationship between the number of R. palmarum larvae and the length and diameter of the trunk segments. By contrast, the soil’s clay loam texture is positively correlated with the number of larvae (rs = 1.00, P < 0.01). The number of larvae was higher in the Tahuayo-Neshuya district samples (145.67 ± 39.67; P Conclusion: Characteristics of the oil palm trunk are not associated with the development of R. palmarum.

HYDROTHERMAL TREATMENT OF OIL PALM WOOD: EFFECT OF TREATMENT VARIABLES ON DIMENSIONAL STABILITY USING RESPONSE SURFACE METHODOLOGY

Oil palm wood (OPW) extracted from felled oil palm trunks during replanting could be a source of replenishment for the depleted timber sources. Nevertheless, dimensional instability of OPW is one of the drawbacks that need to be addressed before it can be utilised efficiently. Therefore, to improve its dimensional stability, hydrothermal treatment using different buffered media was employed in this study and the optimal treatment condition for OPW were investigated. Response surface methodology (RSM) models for treatment temperature, treatment duration and buffered media of hydrothermally treated OPW were developed. OPW samples were hydrothermally treated with different buffered media (pH 4 to pH 9), treatment temperature (60oC to 160oC) and time (13 min to 147 min). Water absorption (WA) and thickness swelling (TS) of the treated samples were determined. It is demonstrated that hydrothermal treatment has improved the dimensional stability of treated samples with treatment temperature appearing to be the most influential factor. Samples treated in an acidic media displayed lower WA mainly due to the fact that higher amount of hydrophilic hemicellulose was degraded under acidic condition. However, lower TS was observed in the samples treated in alkaline media, probably caused by the removal of lignin that increased the porosity of the OPW.

Detoxification of Sap from Felled Oil Palm Trunks for the Efficient Production of Lactic Acid.

The availability of fermentable sugars in high concentrations in the sap of felled oil palm trunks and the thermophilic nature of the recently isolated Bacillus coagulans strain 191 were exploited for lactic acid production under non-sterile conditions. Screening indicated that strain 191 was active toward most sugars including sucrose, which is a major component of sap. Strain 191 catalyzed a moderate conversion of sap sugars to lactic acid (53%) with a productivity of 1.56g/L/h. Pretreatment of oil palm sap (OPS) using alkaline precipitation improved the sugar fermentability, providing a lactic acid yield of 92% and productivity of 2.64g/L/h. To better characterize potential inhibitors in the sap, phenolic, organic, and mineral compounds were analyzed using non-treated sap and saps treated with activated charcoal and alkaline precipitation. Phthalic acid, 3,4-dimethoxybenzoic acid, aconitic acid, syringic acid, and ferulic acid were reduced in the sap after treatment. High concentrations of Mg, P, K, and Ca were also precipitated by the alkaline treatment. These results suggest that elimination of excess phenolic and mineral compounds in OPS can improve the fermentation yield. OPS, a non-food resource that is readily available in bulk quantities from plantation sites, is a promising source for lactic acid production.

Biochemical and Microbial Properties of Palm Wine: Effect of Tapping Length and Varietal Differences

The effects of variety and tapping length on several physical, biochemical, nutritional and micro-biological parameters (viscosity, pH, Total Titratable Acidity (TTA), fermenting microorganisms, contaminants) of palm wine extracted from two varieties of palm oil tree (Dura and Tenera) were studied. Each variety presented its own palm wine specific characteristics regarding the chosen parameters. Microbiological and biochemical contents of palm wine were determined during the tapping of Dura and Tenera felled oil palm trees for 4 weeks. Some differences in chemical compositions between fresh palm wine samples of two palm trees varieties were observed. The exudates obtained during the first day of tapping of Dura palm wine were very sugary, less sour and did not contain substantial concentrations of alcohol but the highest loads of microorganisms were observed in Tenera palm wine. Throughout the tapping of palm wine, yeasts and lactic acid bacteria population changed with undoubtedly influence on the palm wine quality.

Felled oil palm trunk as a renewable source for biobutanol production by Clostridium spp.

This study aimed to convert felled oil palm trunk to biobutanol by Clostridium spp. For efficient utilization of oil palm trunk, it was separated into sap and trunk fiber. The sap was used directly while the trunk fiber was hydrolyzed to fermentable sugars before use. Among five clostridia strains screened, Clostridium acetobutylicum DSM 1731 was the most suitable strain for butanol production from the sap without any supplementation of nutrients. It produced the highest amount of butanol (14.4 g/L) from the sap (sugar concentration of 50 g/L) with butanol yield of 0.35 g/g. When hydrolysate from the trunk fiber was used as an alternative carbon source (sugar concentration of 30 g/L), of the strains tested Clostridium beijerinckii TISTR 1461 produced the highest amount of butanol (10.0 g/L) with butanol yield of 0.41 g/g. The results presented herein suggest that oil palm trunk is a promising renewable substrate for biobutanol production.

Potential of Oil Palm Trunk Sap as a Novel Inexpensive Renewable Carbon Feedstock for Polyhydroxyalkanoate Biosynthesis and as a Bacterial Growth Medium

AbstractUtilization of cheap renewable carbon feedstock for polyhydroxyalkanoate (PHA) production not only brings down its production cost but also ensures sustainability. The scope of this study was to evaluate the potential of sap extracted from felled oil palm trunk (OPT) as a novel inexpensive renewable carbon source for PHA production. OPT sap was found to be nutritionally rich and contained various fermentable sugars (5.5% w/v) as its major constituent. Termite gut isolate, Bacillus megaterium MC1 grew profoundly in mineral medium with OPT sap as carbon source and a cell density of 10.9 g/L was attained after 16 h of cultivation in shake flask cultures. A maximum poly‐3‐hydroxybutyrate [P(3HB)] content (% cell dry weight; CDW) of 30 wt% and a P(3HB) concentration of 3.28 g/L was recorded. Additionally, OPT sap extracted from younger tree trunks with prolonged storage had higher sugar content (10.8% w/v) and, when used as a growth medium without the addition of any nutrients, supported bacterial growth comparable to commercially available media.

Isolation and characterization of high hydrogen-producing strain Clostridium beijerinckii PS-3 from fermented oil palm sap

Felled oil palm trunk (OPT) (25 years old) is an abundant biomass in Southern Thailand. The OPT composition was 31.28–42.85% cellulose, 19.73–25.56% hemicellulose, 10.74–18.47% lignin, 1.63–2.25% protein, 1.60–1.83% fat, 1.12–1.35% ash and trace amount of minerals (0.01–0.40%). Oil palm sap extracted from OPT was found to contain 15.72 g/L glucose, 2.25 g/L xylose, and 0.086 g/L arabinose. A total of twenty samples from hot springs (45–75 °C and pH 6.5–8.4), oil palm sap and palm oil mill effluent were enriched for isolation of hydrogen-producing bacteria. The highest hydrogen-producing strain was isolated from oil palm sap and identified as Clostridium beijerinckii PS-3 using biochemical test and 16S rRNA gene analysis. Among various carbon sources tested, glucose, xylose, starch and cellulose were the preferred substrates for hydrogen production. The strain PS-3 could produce the maximum hydrogen yield of 140.9 ml H 2/g total sugar and the cumulative hydrogen production of 1973 ml/L-oil palm sap. Therefore, C. beijerinckii PS-3 is a potential candidate for fermentative hydrogen production from mixed sugars of the oil palm sap.

Old oil palm trunk: A promising source of sugars for bioethanol production

Abstract Oil palm trees are replanted at an interval of approximately 25 years because of decreased oil productivity of old trees. Consequently the felled trunks are the enormous amount of biomass resources in the palm oil producing countries such as Malaysia and Indonesia. In this report, we found that the felled oil palm trunk contains large quantity of sap, which accounts for approximately 70% of the whole trunk weight, and that sugars existing in the sap increased remarkably during storage after logging. Total sugar in the sap increased from 83 mg ml−1 to 153 mg ml−1, the concentration comparable to that of sugar cane juice, after 30 days of storage, followed by the gradual decrease. The sugars contained in the sap were glucose, sucrose, fructose and galactose, all of which are fermentable by ordinary industrial yeast strains. The results indicate that old oil palm trunk becomes a promising source of sugars by proper aging after logging and, thus, its sap can be a good feedstock for bioethanol.

Growth of yeasts, lactic and acetic acid bacteria in palm wine during tapping and fermentation from felled oil palm (Elaeis guineensis) in Ghana

To investigate the microbiological and biochemical changes which occur in palm wine during the tapping of felled oil palm trees. Microbiological and biochemical contents of palm wine were determined during the tapping of felled oil palm trees for 5 weeks and also during the storage. Saccharomyces cerevisiae dominated the yeast biota and was the only species isolated in the mature samples. Lactobacillus plantarum and Leuconostoc mesenteroides were the dominated lactic acid bacteria, whilst acetic acid bacteria were isolated only after the third day when levels of alcohol had become substantial. The pH, lactic and acetic acid concentrations during the tapping were among 3.5-4.0%, 0.1-0.3% and 0.2-0.4% respectively, whilst the alcohol contents of samples collected within the day were between 1.4% and 2.82%; palm wine which had accumulated over night, 3.24% to 4.75%; and palm wine held for 24 h, over 7.0%. Accumulation of alcohol in palm wine occurs in three stages during the tapping and marketing with the concurrent lactic and acetic acid fermentation taking place as well. Yeasts, lactic and acetic acid bacteria are all important in the fermentation of palm wine and influence the composition of the product.