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The energy sector, currently dominated by fossil fuels, significantly contributes to carbon emissions and climate impacts. This study addresses the urgent need for renewable energy resources and promotes the utilization of waste from Malaysia's palm oil industry. It proposes upgrading conventional palm oil mills to integrated mills to produce valuable biofuels such as methanol (MET) or dimethyl ether (DME). Using Aspen Plus V11 for simulation, mass and energy balances were provided for feasibility analysis, including techno-economic, exergy, and carbon analysis. The integrated process demonstrated 10 to 15% higher exergetic efficiency than conventional mills, enhancing the renewability index by 40% and reducing carbon emissions to 0.50 tonne CO2 per tonne of palm oil. The integrated mills, operating at 61–64% exergetic efficiency, achieve a 28% reduction in exergy destruction when palm wastes are recovered and transformed into biofuels. Despite an 87% increase in non-renewable exergy consumption due to additional operating requirements, the overall renewability index remains high (around 0.9), demonstrating the commercial viability and environmental benefits of this approach. Overall, this study lays the foundation for integrated palm oil mill operation by utilizing palm waste to achieve net zero waste emissions, which is a positive outlook. [ABSTRACT FROM AUTHOR]

In order to evaluate the impact of olive activities on the population health in Fez rural, which is affected by air pollution, a retrospective study of acute respiratory infections (ARI) and chronic was studied (about ten years) in the commune of Ain Taoujdate (30 km of Fez center), known by its strong pollution particularly that of the air caused by industrial activity. Method using was the examination of medical records from 2004 to 2015. Analyzing the evolution of respiratory infections at Ain Taoujdate, we noticed a remarkable and repetitive increase, during olive tree campaign and in the spring (in each year), following the air pollution in the commune and abundance of pollen (pollinosis). Very high cases of pneumopathies recorded during the month of December 2004 and which reached 305 and 124 cases successively and which corresponds to the most important triturating activity during these twelve years of study. On the other hand the asthma crisis of Ain Taoujdate, shows a very large value in olive oil milling season. The main cause seems to be air pollution of Ain Taoujdate, since a large oil mill that releases a huge amount of fume is installed close to the population. Statistical analyzes using principal component analysis (PCA) and ascending hierarchical classification (HAC), were able to show an eventual correlation. This work excludes microbial infections; its limitation is the absence of air quality data and was the consequences to take stock of the impact of air pollution caused by oil mills on respiratory health. [ABSTRACT FROM AUTHOR]

Palm oil mill effluent (POME), wastewater generated from palm oil production, is known for its extremely high chemical oxygen demand and brownish color. Anaerobic digestion is the primary treatment method for POME in the palm oil industry; however, anaerobically treated POME has high concentrations of residual contaminants and color intensity. This study proposes an approach to treat anaerobically-treated POME in recycled water for industrial applications by integrating preliminary organic precipitation, electrocoagulation, and electrooxidation (EO). The EO process was optimized in terms of the current density, electrolysis time, electrode arrangement, and feed flow rate. At a current density of 60 mA/cm2 and an electrolysis time of 9 min, the EO process with a graphite anode and stainless-steel cathode in the monopolar electrode configuration reduced the phenolic concentration and color in the preliminary-treated POME from 8.95 mg/L and 317.19 ADMI to 0.25 mg/L and 26.10 ADMI, respectively. Additionally, the EO process exhibited a 92.26% efficiency in lowering the ammonium-nitrogen content. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: Lipid-degrading bacteria found in processing ponds of palm oil mill effluent are recognized for the capacity to break down lipid using lipase enzyme. Identifying novel strains of these bacteria with high bioremediation potential contributes valuable insights to the sustainable management of palm oil mill effluent. Therefore, this study aimed to identify potential bacteria, assess the in vitro lipid-degrading capabilities, characterize the traits, and evaluate lipid degradation activity of potential isolates from palm oil industry wastewater. METHODS: The method used for exploring the potential of lipid-degrading bacteria in palm oil mill effluent entailed a survey comprising various stages including detection of bacteria presence, in vitro assessment of potential indices, characterization, lipid degradation testing, and determination of lipase activity. FINDINGS: The results showed that several bacteria groups were present in palm oil mill effluent, including 50-74 percent lipolytic, 31-90 percent fermentative, 76-83 percent proteolytic, and 51-74 percent cellulolytic. Selected lipid-degrading isolates demonstrated significant in vitro potential, as evidenced by high lipolytic and fermentative indices. Isolate Enzymatic 3 had the highest lipolytic index, degradation value (48.72 percent), and lipase activity (0.12 units/milliliter), identified as Bacillus cereus central carbon metabolism 2010. Similarly, isolate Fermentative 2 was found to have the highest fermentative index, degradation value (22.35 percent), and lipase activity (0.01 units/milliliter), identified as Bacillus thuringiensis American type culture collection 10792. CONCLUSION: Based on the results, isolates Enzymatic 3 and Fermentative 2 showed promising potential as biological agents for bioremediation of palm oil mill effluent. The results underscored the promising potential of specific bacteria isolates in mitigating lipidrich effluents, advocating for the integration into sustainable wastewater management practices in palm oil industry. This study provided valuable insights for future investigations aimed at unraveling the intricate mechanisms governing lipid degradation and fostering environmentally friendly solutions for industrial waste management. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop an efficient method for enhancing the production of bioethanol in a single‐reactor system (SRS) by implementing acid–base pretreatment and enzymatic hydrolysis techniques, thereby eliminating differentiation and removal processes. The aim was to establish a process for bioethanol synthesis using hydrolyzed palm oil mill effluent (POME) and a locally sourced cellulase enzyme. The pretreatment and enzymatic hydrolysis methods were successfully optimized, resulting in a maximum yield of reducing sugars of 26.6 g/L (53.14%). To achieve the highest bioethanol yield, fermentation was carried out using both the one‐factor‐at‐a‐time (OFAT) and face‐centered central composite design (FCCCD) approaches. The OFAT approach was employed to obtain the maximum bioethanol production, which yielded 6.75% v/v of bioethanol from the hydrolyzed POME using the same bioreactor. In the case of the FCCCD process, the optimal conditions led to a bioethanol production of 7.64% v/v during the fermentation stage. Kinetic analyses of the bioethanol produced revealed a specific growth rate (μ) of 0.198 h−1 and a specific product formation rate (qp) of 0.239 h−1 after 3 days of fermentation. These findings highlight a promising strategy for efficient management of POME through the production of biofuels, which could contribute to the economic growth of the country. [ABSTRACT FROM AUTHOR]

There are more than 149 small palm oil mill factories in Thailand. They mostly produce low-quality crude palm oil (CPO) with high free fatty acid (6-15% of FFA) and low deterioration of bleachability index (≤2.0 of DOBI). This research investigated the application of microwave technology for the production of premium CPO. In this experiment, the CPO quality from two heating processes was compared. The first process was two-timing palm spikelet heating by microwave, and the second one was one-time heating by microwave and hot air drying. The results showed that two processes could produce the premium CPO with less than 1% of FFA, more than 4 of DOBI, about 500 ppm of carotenoid content, and less than 10 meq.kg-1 of peroxide value. The operating times of the first and the second processes were 0.28 and 2.23 h, respectively, compared with 10-15 h using the convention process. In summary, microwave technology could reduce operating time and palm spikelet heating has a high potential process for premium CPO production. [ABSTRACT FROM AUTHOR]

The treatment of palm oil mill effluent (POME) poses a significant challenge for Malaysia's palm oil industry, necessitating compliance with the Department of Environment (DOE) regulations prior to discharge. This study introduces an eco-friendly synthesis method utilizing mangosteen (Garcinia mangostana L.)-leaf aqueous extract to fabricate copper oxide (CuO), zinc oxide (ZnO) nanoparticles (NPs), and their nanocomposite (CuO-ZnO NCs). The physicochemical properties of these nanomaterials were characterized using various analytical tools and their effectiveness in reducing the chemical oxygen demand (COD) of palm oil mill effluent (POME) was assessed under the illumination of two types of light sources: monochromatic blue- and polychromatic white-light emitting diodes (LEDs). CuO-ZnO NCs demonstrated superior performance, with the lowest energy bandgap (1.61 eV), and achieved a COD removal efficiency of 63.27% ± 0.010 under blue LED illumination, surpassing the DOE's discharge limit of 100 mg/L. This study offers a cost-effective and environmentally friendly method for synthesizing heterojunction materials, which show great potential as photocatalysts in reducing POME COD to permissible levels for discharge. [ABSTRACT FROM AUTHOR]

Palm oil Mill effluent Materials (POME) are significantly more contaminated than municipal sewage due to their high chemical and biological oxygen demand (BOD and COD). This study examines the properties of POME wastewater under typical physical settings to track the growth conditions of microalgae, namely Botryococcus sp., in various volumes at varying POME dilutions. Begin with analyzing POME's water quality measurements and conclude the growing conditions of microalgae. Botryococcus sp. microalgae could not flourish in diluted raw POME. However, it was well propagated in diluted anaerobic POME under adequate light and oxygen conditions. The finding shows that diluted anaerobic POME 70% is the ideal dilution for microalgae Botryococcus sp. to proliferate. Raw POME is physically described as a thick, brownish liquid with a high total solids and turbidity concentration that is contained in water. The study explores the use of Botryococcus sp. culture and propagation in POME materials for sustainable bioenergy production, highlighting the potential of microalgae for future economic benefits. [ABSTRACT FROM AUTHOR]

Enriched olive oil combines olive oil with plants for enhanced flavor and potential health benefits, offering a versatile culinary ingredient. This process combines the natural goodness of olive oil with the unique characteristics of plants. The aim of this work was to study the effect of rosemary (Rosmarinus officinalis) as a food additive (E 392) in the enrichment of ripe and fallen olives on the quality of the resulting flavored olive oil. Olive fruits at different stages of maturation green (ST1), mixed (ST2), black (ST3), and fallen in the ground (FO) were crushed with rosemary at two different percentages (2 and 5% w/w). Quality parameters, fatty acid profile, antioxidant profile, and volatile composition were evaluated. For ST3 and FO, rosemary addition decreased free acidity values, peroxide index, K232, and pigment content. Total phenols increased by 34 and 55% for ST3 and FO, respectively with 2% rosemary. As for bio-phenols, this process influenced antioxidant activity. In fact, 2,2-diphenyl-1-picrylhydrazyl (DPPH) activity is improved by 59 and 51%, respectively, for ST3 and FO oils flavored with 5% rosemary. As anticipated, the volatile profile changed significantly due to the rosemary addition, inducing the presence of terpene compounds, such as α-pinene, α-cymene, camphene, β-pinene, and α-terpineol. These findings prove that aromatization process improves the quality and the antioxidant profile of olive oils obtained from mature and fallen olives, and could help in solving the economic problems of oil mills. Other plants such as garlic, lemon, thyme, and others can be studied to find out if better results can be achieved. [ABSTRACT FROM AUTHOR]

AbstractThis research performed cellulase production by Aspergillus fumigatus A4112 and evaluated its potential use in palm oil mill effluent (POME) hydrolysis to recover oil simultaneously with the generation of fermentable sugar useful for biofuel production under non-sterilized conditions. Empty fruit bunch (EFB) without pretreatment was used as carbon source. The combination of nitrogen sources facilitated CMCase production. The maximum activity (3.27 U/mL) was obtained by 1.0 g/L peptone and 1.5 g/L (NH4)2SO4 and 20 g/L EFB at 40 °C for 7 days. High level of FPase activity (39.51 U/mL) was also obtained. Interestingly, the enzyme retained its cellulase activities more than 60% at ambient temperature over 15 days. In enzymatic hydrolysis, Triton X-100 was an effective surfactant to increase total oil recovery in the floating form. High yield of reducing sugar (50.13 g/L) and 21% (v/v) of floating oil was recoverable at 65 °C for 48 h. Methane content of the raw POME increased from 41.49 to 64.94% by using de-oiled POME hydrolysate which was higher than using the POME hydrolysate (59.82%). The results demonstrate the feasibility of the constructed process for oil recovery coupled with a subsequent step for methane yield enhancement in biogas production process that benefits the palm oil industry. [ABSTRACT FROM AUTHOR]

Potential use of acid sulfate soils in agriculture is faced by low pH and the presence of a pyrite layer especially in dry conditions. In order for potential acid sulfate soils to support corn growth during the dry season, technological input is needed to improve soil fertility and overcome water availability by organic fertilizer palm oil mill effluent (POME) plus zeolite. The study used a Split Plot Design with two treatment factors. The treatment factors consisted of plots of water availability: C1 = 100%, C2 = 75%, C3 = 50%, C4 = 25%. POME subplot factor: L0 = No POME, L1 = Secondary Anaerobic POME (zeolite 0%) dose of 1000 ml, L2 = POME Acidification Pool (zeolite 10%) dose of 1000 ml. Availability of water and the provision of POME plus zeolite affect pH, organic-C, total-N, P-Bray I, and soil CEC. In terms of plant growth, both treatments also influence canopy dry weight, seed weight, N content, P and proline leaf corn. Palm oil mill effluent acidification pool plus zeolite 10% dose of 1000 ml increases the adaptability of plants to water shortages and the fertility of potential acid sulfate soils, and the growth and production of corn. [ABSTRACT FROM AUTHOR]

Thailand has attempted to produce sustainable palm oil by encouraging grower-developed Roundtable on Sustainable Palm Oil (RSPO) criteria with many campaigns, but the target has still not been achieved. Here, we determined the tangible financial benefits of certified and noncertified farmers of 3 groups, namely, those with a large planting area, cooperative members, and small growers supported by palm oil mills, to illustrate the advantage of RSPO certification. The results showed that all certified groups received greater net returns than the noncertified groups, with net return differences of 0.34 baht per kilogram for large planting areas, 0.70 baht per kilogram within the cooperative group and 0.13-1.10 baht per kilogram under the group supported by palm oil mills. However, the increasingly important RSPO certification should provide knowledge to improve agricultural practices because they are affected by increasing net returns and reducing variable costs. The government should provide financial loans for growers who want RSPO certification because of the high costs of certification and develop criteria, and grower integration can increase negotiation power to decrease the cost of production. [ABSTRACT FROM AUTHOR]

Biogas is a cost-effective, efficient, environmentally friendly, and renewable alternative energy source. While biogas contains CH4, it also contains impurities in the form of 27–45% CO2 gas. Therefore, it is necessary to purify biogas by removing CO2 gas as it can reduce the calorific value of CH4, the main component of biogas. The process of methane purification can be achieved through adsorption. Bottom ash, derived from palm oil mill waste, shows great potential for methane purification by effectively adsorbing CO2. This research simulated the methane purification process using the computational fluid dynamics (CFD) method with the student version of the ANSYS R20 software. The study utilized an adsorbent made from bottom ash obtained from palm oil mill waste. The main objective was to investigate the performance of bottom ash as an adsorbent for removing CO2 gas in a continuous gas flow within an adsorption column. The study involved varying the column bed height (4 cm, 8 cm, 12 cm) and gas flow rate (10 L/min, 15 L/min, 20 L/min). The results showed that the highest efficiency in removing CO2 gas was 84.53% with a bed height of 12 cm and a flow rate of 10 L/min, while the lowest efficiency was 47.87% with a bed height of 4 cm and a flow rate of 20 L/min. Furthermore, the highest adsorption capacity for CO2 gas was 1.64 mg/g with a bed height of 12 cm and a flow rate of 10 L/min, while the lowest capacity was 0.93 mg/g with a bed height of 4 cm and a flow rate of 20 L/min. The linearization of adsorption isotherm data indicated that the CO2 gas adsorption process using bottom ash adsorbent followed the Langmuir model. [ABSTRACT FROM AUTHOR]

Metal cutting researchers attempt to develop technology for metal cutting and use of cutting fluids have been continuous due to increasing demands for high productivity. This work reports on the effect of coconut oil under minimum quantity lubrication (MQL) during end milling of AL7049. Dry, wet and MQL approaches are all used to conduct the experimental studies. In contrast to dry and wet machining, it is apparent that MQL generates surfaces with less roughness. A multilayer perceptron (MLP) prediction model was developed considering the real-time dataset with three inputs, and an output that led to prediction of surface roughness. It was analyzed to determine the appropriate activation function and observed that ReLU activation function outpaces sigmoid and tanh and adapted to the proposed solution. K fold cross-validation was done for the developed MLP model with backpropagation to substantiate high accuracy in predictions than KNN and linear regression. The MQL will be good alternative to wet machining and also environmentally friendly machining solution. [ABSTRACT FROM AUTHOR]

The palm oil industry is one of the key players in contributing to Malaysia's economy. Palm oil mill effluent (POME), a significant by-product of the oil extraction process, requires mandatory remediation to ensure proper treatment and disposal. Bioremediation using microalgae is a cost-effective and sustainable approach. This study aims to utilise pure and mixed microalgal species, Chlorella vulgaris and Tetradesmus bernardii, in phycoremediation and biomass production in different concentrations of POME (20%, 40%, 60%, and 80%). Cultivation of microalgae was carried out in 200 mL medium with pH 7-7.8, room temperature of 25±1°C for 21 days and continuous light illumination at 2000 lux. The highest biomass productivity was observed in 20% POME for mixed microalgae (mean = 0.1733 mg.mL-1 ± 0.0057), followed by C. vulgaris (0.1633 mg.mL-1 ± 0.0057) and T. bernardii (0.1603 mg.mL-1 ± 0.0020). Similarly, the highest nutrient removal was observed in 20% POME for mixed microalgae (COD:66.9801%, TN:86.9565%, TP:86.9655%), followed by C. vulgaris and T. bernardii. The results showed positive effects on growth, increased biomass production, and nutrient removal, with 20% POME being the optimal concentration for microalgae. Valuable by-products, such as high-quality pigments and biomass, are also generated by applying microalgae for remediation. Mixed microalgae are superior in the remediation of POME compared to single-culture algae. Treating wastewater through microalgal bioremediation is highly efficient in nutrient removal. This research has contributed towards the use of mixed microalgae to achieve effective nutrient removal and biomass for future industrial applications. [ABSTRACT FROM AUTHOR]

In the last two decades, Italian oil mill modified its structures assuming a more industrial aspect, yet assuring good yields, olive oil quality and an economic and sustainable utilisation of the by-products. The modern oil mill adopts the continue centrifugation system, twoor three-phase, and carries out the crushing of olives by the metallic crushers, having different characteristics able to influence the oil yield and the organoleptic properties of virgin olive oil. The following operation of olive paste malaxation, if carried out at rational time and temperature, favours the coalescence phenomenon and “frees” most of the oil contained in the cell vacuoles, allowing to extract up to 85-86% of the oil contained in olive fruits, without a negative effect on olive oil quality. Then, olive paste is sent to the centrifugal decanter to separate virgin olive oil from the aqueous and solid phases (decanter at 3 phases) or from the solid phase only (decanter at 2 phases). Some oil mills, having a larger loading capacity, with the end to increase oil extraction yield, carry out the double extraction of olive oil, using another specific decanter. Moreover, several oil mills have also the machine able to separate the stone fragments from olive pomace with the end to utilize them as fuel. Finally, oil mill equipped with the three phases centrifugal decanter utilizes the liquid by-product (oil mill wastewater) as fertiliser of the soil, in particular, by its controlled spreading on olive grove. In the region where there aren’t industrial structures to extract pomace oil, oil mill can utilise the wet olive pomace spreading it on cultivated soil, of course, after the separation of the stone fragments. [ABSTRACT FROM AUTHOR]

Agro industries have produced huge amounts of waste, influencing the environment. Palm oil clinker (POC), routinely dumped from Malaysian palm oil mills, is one of these waste products. This research investigates the feasibility of using it as a filler substitute in hot mix asphalt (HMA) as an alternative avenue to utilize this waste. The waste POC powder (POCP) is comparable to the properties of the traditional fillers used-granite stone dust (GSD), according to physiochemical analysis. The POCP passes through 75 µm sieve, and 6% (w/w) of the filler was substituted by 0%, 20%, 40%, 60%, 80%, and 100% (w/w) of the GSD. HMA mixes were prepared for various percentages using the Marshall mix design to evaluate their respective optimum bitumen contents (OBC). Subsequently, at OBC, the influence of POCP on the HMA volumetric, Marshall properties, Cantabro test resilient modulus, and moisture damage tests was investigated. The study revealed that all POCP mixtures improve performance in terms of stability, stiffness, and higher resistances against moisture damage than the control mixture. The improvement could be attributed to the synergistic influence of POCP pozzolanic reaction and fineness, resulting in a thicker refined mastic between POCP and bitumen, producing more durable HMA. However, based on the study findings, 80% of POCP filler for HMA mixes can be considered the optimal content to improve its properties. In conclusion, the study depicts the viability of utilizing POCP as a replacement for conventional filler to promote sustainability and provides a proper channel for its disposal. [ABSTRACT FROM AUTHOR]

In recent decades, the province of Taza has undergone extensive agricultural modernization, marked by an increase in industrial units such as modern oil mills and olive canneries. At the same time, rapid population growth has exacerbated an important problem, the deterioration of the quality of water resources in limited quantities. This study explored the heart of matter by meticulously sampling physico-chemical and bacteriological parameters at eight strategically chosen sites. Conducted in late July 2021, the survey focused on the surface waters of the Innaouene River, providing a timely and insightful examination of the complex dynamics of water quality in the context of modernization and demographic change. This work focused on the determination of physicochemical and microbiological parameters of water. The results of the analyses show that this river is subject to multiple constraints and reaches its tolerance level on most of its sections. A multivariate statistical approach: principal component analysis (PCA) has shown that water pollution in the Innaouene River is mainly related to untreated wastewater discharges into streams. Water quality is considered bad to very bad. Therefore, ecological and health impacts can occur. [ABSTRACT FROM AUTHOR]

The present investigation analyzes the influence of water content in a biodiesel blend using palm oil mill effluent: POME (8%). Two water emulsion blends were tested: POME (8%) + H2O (5%) and POME (8%) + H2O (10%). The tests were performed on a stationary diesel engine operating at four load conditions (25%, 50%, 75% and 100%). From the results, it is shown that the blends POME (8%) + H2O (5%) and POME (8%) + H2O (10%) allow a decrease of 2.2% and 4.7% in NOx emissions. In this way, the NOx formation problems of biodiesel are minimized. The evaporation of the water microparticles in the blends POME (8%) + H2O (5%) and POME (8%) + H2O (10%) improves the homogeneity between the air and the fuel. This contributes to a 2.65% decrease in BSFC and a 1.65% increase in BTE compared to POME (8%). Additionally, water emulsions achieve a 14.6%, 7.3%, 13.4%, 1.8%, and 14.1% reduction in CO, CO2, HC, NOx, and smoke opacity emissions compared to conventional diesel. In general, the emulsified blends POME (8%) + H2O (5%) and POME (8%) + H2O (10%) contribute to a greater reduction in engine pollutant emissions, as well as an improvement in engine performance parameters when compared to POME (8%). [ABSTRACT FROM AUTHOR]

Ten species of white-rot fungi were evaluated for their ability to decolorization of palm oil mill effluent. The highest decolorization efficiency was found with Trametes elegans (PP17-06), followed by Ganoderma sp.2 (PW17-06) and Ganoderma sp.2 (PW17-177), respectively. T. elegans was further evaluated for the long-term performance of decolorization for 24 d. The optimal retention time for the decolorization was 8 d, with a color removal efficiency of 47.7%. Beyond 18 d of incubation, decolorization efficiency was reduced due to the autolysis of enzymes. During the biodegradation process, manganese peroxidase enzyme activities reached a maximum of 36.03 U.L-1. However, no significant laccase and lignin peroxidase activities were observed. T. elegans was also assessed for decolorization performance through biosorption on mycelial biomass. The synthesis of the enzyme was prevented by exposing the mycelium to HgCl2. Within an optimal contact time of 2 d, decolorization efficiency reached 12.5% with ADMI reduction from 4259.0 (±20.1) ADMI to 3727 (±104.04) ADMI. Results indicate that the adsorption capacity was reached at this time, and no significant color removal can be achieved by biomass. Results obtained in this study showed the potential of T. elegans in decolorizing palm oil mill effluent. [ABSTRACT FROM AUTHOR]

Palm oil derived from the fruits of Elaeis guineensis Jacq. has global economic importance and is largely produced in tropical regions. The palm oil production process leads to a highly polluting waste called palm oil mill effluent (POME). A strategy commonly used by producers to overcome environmental issues and to improve soil fertility is the reuse of POME as a fertilizer due to the chemical and biological characteristics of the effluent. In this research, three groups were analyzed: soil without POME application (control group) and soil samples after 4 and 9 days of POME application. An environmental DNA metabarcoding approach was used. eDNA was extracted, and the V4 region of the 16S rRNA gene was amplified and sequenced in the Illumina MiSeq platform. The abundance of Proteobacteria (48.1%) and Firmicutes (9.0%) was higher in fertilized soil, while Bacteroidetes (20.3%) and Verrucomicrobia (7.8%) were more abundant in control soil. Additionally, the effluent seemed to modify soil characteristics favoring taxa responsible for the mineralization of organic compounds and nitrogen fixation such as species of Gammaproteobacteria class. Our study highlights the influence of POME on soil biological components and contributes to the sustainable production of palm oil in the Amazon. [ABSTRACT FROM AUTHOR]

The research experimentally investigated biohydrogen production with a light intensity of 4500 lux using indigenous bacteria in DEPOME. The study was conducted in three stages: identified indigenous bacteria through next-generation sequencing (NGS) DNA, analyzed DEPOME characteristics, and produced biohydrogen. Biohydrogen production was carried out under two initial substrate pH conditions: neutral (pH 7) and natural pH substrate (4.9–5.4) for 88 h at a controlled temperature of 30 °C, with measurements of gas production and observations of changes in dissolved oxygen (DO), oxidation-reduction potential (ORP), and substrate pH taken at 4-h intervals. Rhodopseudomonas palustris bacteria was identified as indigenous bacteria for photo-fermentation in POME. The yield, gas production rate, and light conversion efficiency (LCE) were found to be 147.65 mg-H 2 /L-Depome, 1.68 mg-H 2 /L-Depome/h, and 11.75 % under the initial pH neutralization treatment, while without initial pH treatment, the values were 78.5 mg-H 2 /L-Depome, 0.89 mg-H 2 /L-Depome/h, and 6.25 %. [Display omitted] • Rhodopseudomonas palustris was found as indigenous bacteria on POME. • pH is one of the most influential factors for good bacterial growth. • Changes in ORP and pH during the process have an impact on biohydrogen yields. • DEPOME has good potential as a photo-fermentation substrate. [ABSTRACT FROM AUTHOR]

The treatment of palm oil mill effluent (POME) via adsorption was investigated using a novel nanocomposite powder with the addition of titanium (IV) dioxide (TiO2) and montmorillonite clay (MMT). Reduced heavy metal content, turbidity, pH, chemical oxygen demand (COD), and total suspended solids (TSS) in POME supported this result. The adsorption processes were carried out in POME with pH 4.4, 658 FAU turbidity, 1256 mg/l COD, and 563 mg/l TSS at a constant mixing speed of 180 rpm for 48 h, with different dosages of adsorbent. The atomic adsorption spectrometry (AAS) analysis revealed that MMT clay was effective in removing lead (Pb) and zinc (Zn) by 86.7 and 97.3%, respectively, aided by the role of activated carbon and photocatalytic behavior of TiO2 to remove recalcitrant organic pollutants which result in 91.6% reduction in POME turbidity. The final pH value of POME was within the allowable discharged limit as stated in the Environmental Quality Act 1974 (EQA 1974). The response surface methodology (RSM) was modeled based on the COD and TSS analysis results. The findings determined that 1wt% KOH-AC, 0.628wt% TiO2, and 2wt% MMT clay were the best composition values of novel nanocomposite in showing the most effective reduction of COD and TSS. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) are a viable source of clean and renewable energy from wastewater and gaining attention on a global scale. Thus, this research work focuses on the energy production from high-strength palm oil mill wastewater using MFCs. A state-of-the-art technique for improving the performance of MFCs by covering a carbon fibre anode with various sized powdered activated carbon (PAC) particles was investigated. In addition, the MFCs were tested at various hydraulic retention times (HRT) to assess the performance displayed by modified MFCs. Results showed that a relatively smaller amount of PAC with a diameter of 13 μm coated at the anode during the cultivation stage at a shorter hydraulic retention time (4 days) would produce 504.1 ± 8.7 mW m−3 of power, 39.9 ± 2.9% of chemical oxygen demand removal efficiency, and 299 ± 63 mL of biogas. While, MFC running at a longer hydraulic retention time (12 days) was able to produce more power and had better effluent quality than those operating at a shorter hydraulic retention period. [Display omitted] • Ability of MFC to produce energy and treat palm oil wastewater simultaneously. • MFC-carbon cloth anode coated PAC produced almost doubled energy than control. • About 10% higher COD removal with MFC-carbon cloth anode coated PAC than control. • Inverse relationship between biogas production and power generation was identified. [ABSTRACT FROM AUTHOR]

Malaysia is one of the most important palm oil producers and exporters in the whole wide world. There has been a rapid development of new palm oil plantations and palm oil mills in this country. The palm oil industry plays a vital role in the economic growth of Malaysia. However, as the palm oil industry grows bigger and wider, a huge amount of palm oil waste is produced which is an alarming issue considering it can cause pollution and have a negative effect on the environment. Raw Palm Kernel Shell (PKS) derived from palm oil waste can be converted into Activated Palm Kernel Shell (APKS) which has the potential to be a value-added biofiller in rubber vulcanizates. Thus, in this study, APKS is prepared through a carbonization process at a temperature of 900 °C and an activation process via steam treatment and used as filler in Carboxylated Nitrile Butadiene Rubber (XNBR). The aim of this study is to evaluate the influence of different loading ratios of APKS on the swelling index measurement, bound rubber content (BRC), abrasion resistance, compression set, and hardness of XNBR vulcanizates. APKS is incorporated in XNBR at different loading ratios, ranging from 0 to 50 phr and these APKS-filled XNBR vulcanizates are prepared with a two-roll mill. The overall physico-mechanical properties of APKS-filled XNBR vulcanizates showed increment in terms of BRC, compression set, and hardness as the loading ratio of APKS increased. XNBR vulcanizates with a higher loading ratio of APKS also showed a decrease in swelling index measurement and volume loss which would indicate high abrasion resistance. These results could be attributed to the porosity of APKS as shown in the morphological analysis which provided a high surface area of contact for crosslinking and mechanical interlocking. This proves APKS could potentially be a semireinforcing filler for rubber vulcanizates, especially for XNBR vulcanizates as XNBR vulcanizates were able to achieve high abrasion resistance and high hardness with the incorporation of APKS. With this, the conversion of PKS into APKS could help to reduce palm oil waste and provide an environmentally friendly, sustainable biofiller option to rubber researchers and manufacturers who are looking for an alternative to petroleum-based fillers. This would be very beneficial for both the palm oil industry and the rubber industry. [ABSTRACT FROM AUTHOR]

Background: Steam explosion pretreatment has been proven to be an effective treatment for breaking down the recalcitrant character of lignin–carbohydrate complexes (LCC) in lignocellulosic biomass. This study investigated the production of lignin-derived products from steam-exploded palm oil mill lignocellulosic biomass waste (POMLBW), that is, empty fruit bunches (EFB), kernel shells (KS), and kernel fibers (KF), also known as mesocarp fibers. Steam explosions cause lignin depolymerization, which forms various polyphenols. The low average molecular weight of the steam-exploded lignin-derived products and their antioxidant activities could potentially enhance their antimicrobial activities. Methods: POMLBW was steam-exploded with various degrees of severity factors (R0: 4.03, 4.91, 5.12, 5.35, and 5.65). Steam-exploded POMLBW produces lignin-derived products such as low-molecular-weight lignin (LML) and water-soluble lignin (WSL). Antioxidant activity was evaluated using 0.5 mM 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. Polyphenol content was evaluated using the Folin–Ciocalteu method. The antimicrobial activity was evaluated using an agar diffusion assay with Gram-positive and Gram-negative bacteria, and the thermal characteristics were evaluated using differential scanning calorimetry and thermogravimetric analysis. Results: WSL and LML resulted in high radical scavenging activity (RSA) of approximately 95% and 80%, with 0.25 g/L and 0.5 g/L of EC50, where the polyphenol amount was 242–448 mg/g (catechin eq.) and 20–117 mg/g (catechin eq.) under all LML and WSL conditions, respectively. The steam-exploded POMLBW had an average molecular weight of 1589–2832 Da, and this condition, including high RSA and polyphenol amounts, was responsible for the high antimicrobial activities of LML against both Gram-positive (Salmonella enterica, Pseudomonas aeruginosa, and Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria. Additionally, the thermal properties investigations revealed that the glass transition temperature was 80–90 °C (Tg), the melting temperature (Tm) was 338–362 °C, and the start temperature was 101–128 °C at the beginning of mass loss. Conclusions: These results show that the lignin-derived product from steam-exploded POMLBW has the potential for antioxidant (LML and WSL) and antimicrobial (LML) applications with good thermal resistance. [ABSTRACT FROM AUTHOR]

Facultative hydrogen-producing bacteria hold immense potential for fermentative hydrogen and valuable metabolite production. In this study, a mesophilic hydrogen-producing bacterium was isolated from palm oil mill effluent (POME) and identified as Enterococcus faecalis isolate VT-H1 using hybrid sequencing technologies. Our investigation encompassed the growth of the isolate and its capacity for hydrogen and volatile fatty acid (VFA) production. The results revealed that optimal growth occurred when glucose was utilized at 37 °C and initial pH of 7.0, resulting in a final OD 600 of 2.58. The isolate demonstrated exceptional hydrogen production capabilities, achieving a maximum cumulative hydrogen yield of 2.22 mol-H 2 /mol-glucose at 30 °C and pH 7.0, outperforming previously reported E. faecalis strains by 5.84-fold. Kinetic analysis revealed favorable parameters for hydrogen production at 30 °C, with maximum hydrogen production (H m = 2.63 mol-H 2 /mol-glucose), maximum hydrogen production rate (R m = 0.03 mol-H 2 /mol-glucose·h), and lag-phase time (LPT = 18.34 h). Additionally, E. faecalis isolate VT-H1 exhibited significant butyric acid production (63.0 mM) alongside acetic acid (7.0 mM). Genome analysis unveiled the presence of key enzymes associated with hydrogen production, including formate hydrogen lyase (FHL) complex with formate dehydrogenase subunit alpha (FDH-α), bidirectional [NiFe] hydrogenase, NADH-dependent oxidoreductase subunit E, and NADH-quinone oxidoreductase subunit F. Moreover, genes associated with butyric acid production were also identified. These findings highlight the potential of E. faecalis isolate VT-H1 as a promising candidate for sustainable hydrogen and VFA production. Its unique characteristics, distinct genetic profile, and exceptional hydrogen and VFA production capabilities bring exciting opportunities for future biotechnological applications and further research to optimize and scale-up its potential for industrial use. [Display omitted] • A novel hydrogen-producing bacterium, Enterococcus faecalis VT-H1 , was isolated. • E. faecalis VT-H1 shows high hydrogen yield, 2.22 mol-H 2 /mol-glucose. • Butyric acid was found to be the dominant volatile fatty acid in the system. • Optimal hydrogen and butyric acid production conditions were 30 °C with pH 7.0. • E. faecalis VT-H1 contains multicomplexes in its formate hydrogenlyase system. [ABSTRACT FROM AUTHOR]

Rhamnolipid has gained much attention in various fields owing to its distinctive functional properties compared to conventional chemical surfactants, which are mostly derived from petroleum feedstock. Production cost is one of the main challenges in rhamnolipid production, particularly when using refined substrates. One possible solution is to use agro-industrial wastes as substrates for rhamnolipid production. This is a promising strategy due to their abundance and commercially low value, while simultaneously alleviating an agro-industrial waste management problem in the environment. This study aims to evaluate agro-industrial wastes from local crops as possible low-cost alternative substrates for rhamnolipid production by a local isolate, Pseudomonas aeruginosa USMAR2. Various liquid wastes, namely sugarcane molasses, rice washing water, overly mature coconut (OMC) water, empty fruit bunch (EFB) steam effluent, palm sludge oil (PSO) and palm oil mill effluent (POME) were screened as the main carbon source supplementing mineral salt medium (MSM) in the fermentation of P. aeruginosa USM-AR2. Batch fermentation was carried out in a shake flask system, agitated at 200 rpm and incubated at room temperature, 27 ± 2°C for 120 h. Among the substrates tested, PSO exhibited the highest biomass at 20.78 g/L and rhamnolipid production at 1.07 g/L. This study has shown the potential of agro-industrial wastes in Malaysia as an alternative resource for rhamnolipid production, transforming them into value added products, while reducing the amount of wastes discharged into the environment. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: To improve photocatalytic degradation perfomance, photocatalyst particles with a larger surface area preferred. The effectiveness of titanium dioxide as a photocatalyst depends on the synthesis method used. The method affect the particle size, crystallinity and phase composition of the produced catalyst. This study aims to develop a green synthesis process of nano-titanium dioxide photocatalysts for the advanced treatment of palm oil mill effluent. METHODS: The green synthesis of titanium dioxide nanoparticles used de Man-Rogosa-Sharpe broth media containing Lactobacillus bulgaricus culture and titanium oxyhydroxide metal oxide. The factors investigated were the molarity of titanium oxyhydroxide (0.025 molar; 0.035 molar and 0.045 molar) and temperature (40; 50 and 60 degrees Celsius). The synthesized photocatalyst was characterized using a particle size analyzer to determine the particle size. The produced photocatalyst with a nanoparticle size range of 1-100 nanometer was further characterized using scanning electron microscopy-energy dispersive X-ray and X-ray diffraction. The photocatalyst was tested for advanced treatment of palm oil mill secondary effluent. The factors investigated in this test included the irradiation time and titanium dioxide photocatalyst dosage. The treatment performance was evaluated in terms of effluent quality and pollutant elimination efficiency. FINDINGS: Nano titanium dioxide photocatalysts have been synthesized through titanium oxyhydroxide metal oxide biologically using Lactobacillus bulgaricus. The synthesis process at a temperature of 60 degrees Celsius and a 0.025 molar metal oxide solution produced a titanium dioxide photocatalyst with a size of 33.28 nanometer. The content of titanium and oxygen constituents in the photocatalyst was confirmed to be 39.06 percent and 47.95 percent respectively, with 67.6 percent titanium dioxide crystallinity in a theta degree of 25.4. This indicates that the green synthesis has produced an anatase diffraction nano titanium dioxide photocatalyst. Testing the titanium dioxide photocatalyst to treat palm oil mill secondary effluent yielded in elimination efficiency of 16.16-27.27 percent for chemical oxygen demand and 11.05-21.95 percent for biological oxygen demand. Phenol, which is toxic and difficult to degrade biologically, could eliminated significantly (up to 81.12 percent) using a photocatalyst dose of 1 gram per liter at a time irradiation of 2.5 hour. CONCLUSION: The biological synthesis of nano titanium dioxide photocatalysts is affected by temperatures and metal oxide concentrations. The photocatalytic process for advanced treatment of palm oil mill secondary effluent shows that this synthesis process effectively eliminates phenols. Some compounds such as lignin, amino acids, and pectin are not significantly mineralized using this process. [ABSTRACT FROM AUTHOR]

Palm oil extraction is one of the important industries in Malaysia. The extraction of palm oil will not only result in the production of palm oil for human consumption but also generate palm oil mill effluent (POME), which contains highly polluting properties. Synthetic coagulants such as aluminum sulfate (alum), aluminum chloride, and sodium aluminate contribute toward environmental pollution and risk to human health. Thus, natural coagulants and flocculants have been introduced throughout the globe to slowly replace synthetic coagulants. In this study, rambutan (Nephelium lappaceum) seed was used as natural coagulants combining with aloe vera as natural flocculants. The standard jar test experiments were conducted to study the effects of pH, coagulant dosages, and rapid mixing speed on the removal efficiency of chemical oxygen demand (COD), total suspension solid (TSS), and turbidity of POME. The model of the coagulation–flocculation process was evaluated by using response surface methodology (RSM) and artificial neural network (ANN). RSM associated with Box–Behnken design was used to identify the optimum parameters (inputs), which consist of pH, coagulants dosages and rapid mixing speed for the optimum removal efficiency (outputs) of COD, TSS, and turbidity of POME. In terms of removal efficiency of COD, TSS, and turbidity of POME, rambutan seed has the optimum removal efficiency of 28.48%, 56.38%, and 60.36%, respectively. ANN was utilized with the aim of evaluating the performance of 12 training algorithms to predict the output results. Levenberg–Marquardt (LM) training algorithm was verified to be the best training algorithm for coagulation–flocculation process of rambutan seed based on the lowest mean squared error (MSE), mean absolute error (MAE), and mean absolute percentage error (MAPE) for validation data and the correlation coefficient R of.9347. [ABSTRACT FROM AUTHOR]

While palm oil mill effluent (POME) from different sources will have varying characteristics due to the different process flows in mills, efficient monitoring and performance evaluation of anaerobic digesters in POME treatment are crucial to ensure stable biogas production with minimal operational problems. Therefore, this study aims to evaluate and compare the performances of in‐ground lagoon anaerobic digesters under mesophilic conditions in four different biogas plants (BGPs A, B, C and D) located in Malaysia with respect to total chemical oxygen demand (COD) removal and total biogas produced. Results show that all BGPs are still functioning well with satisfactory methane yields (.135–.364 Nm3 CH4/kgCOD removed) and COD removal efficiencies (67%–85%). ANOVA analysis shows that organic loading rate (OLR), temperature (T) and recirculation ratio (RR) have significant effects on the COD removal and biogas production of all four plants. BGP B has the highest amount of biogas produced (4.12 × 105 Nm3/month) and COD removal rate amongst other BGPs due to its most stable and lowest T (<40°C), high RR, and consistent and high COD load. Conversely, BGP D has the lowest COD removal and biogas production, which are mainly contributed by a high COD inlet (92 000 mg/L) and a high T in the anaerobic digester (48.7°C). Despite having a similar design of an anaerobic digester, this comparative study reveals that different BGPs will have different optimum operating conditions and limitations, depending not only on the operating conditions of the BGP (OLR, T and RR) but also on the raw POME quality stemming from the palm oil milling process. A future study would be focused on the optimisation of four BGPs for maximum biogas removal. [ABSTRACT FROM AUTHOR]

Sunflower oil (SFO) is faced with serious oxidation problems during the deep-frying of Chinese Maye, and the search for natural antioxidants has become a focus of scientific research due to the potential toxicity of synthetic antioxidants. In the present study, the Foeniculum vulgare Mill. essential oil (FVEO), tert-butylhydroquinone (TBHQ) were added to SFO for a 30 h deep frying experiment and the results showed that FVEO added to sunflower oil at 1 g/kg was similar to that of TBHQ-0.01 g/kg, and FVEO-1.5 g/kg would promote the oxidation of SFO. FVEO to sunflower oil also prominently restrained the decrease of the sensory properties of the fried product, Chinese Maye, including appearance, taste, flavor and overall acceptance by 24.2%, 20.2%, 46.1% and 56.0% (p < 0.01 or p < 0.05), respectively. The results indicated that FVEO could be used as a natural antioxidant to replace TBHQ in the deep-frying process of SFO, but further research is needed on the key antioxidant constituent of FVEO. [ABSTRACT FROM AUTHOR]