Synergistic effect by Sorghum bicolor L., citric acid, biochar, and vermiwash amendment for the remediation of a mine-contaminated soil.

Phytoremediation is an in situ remediation and eco-friendly technique employing accumulator plant species to remove trace elements (TEs) from contaminated sites. Moreover, it has been demonstrated that both natural and synthetic amendments can enhance trace elements (TEs) phytoremediation from polluted soils through bioenergy crops. This work assessed the synergistic impact of two tested biochar (BC) from data palm (B1) and Prosopis (B2) (1.5%/ kg), citric acid (CA, 1.5 mmol/kg) and vermiwash (VW, 20 ml/kg) to enhance the remediation of tested TEs (Mn, Zn, Cd, Pb, Ni, Cu, and Fe) from Mahad AD'Dahab mine-contaminated soil by sorghum (Sorghum bicolor L.). The BC and CA amendments alone and combined with VW significantly augmented the proliferation and survival of sorghum grown in mine-contaminated soil. Considering the individual and combined applications of VW and BC, the influence on plant growth followed this order: K < VW < B2 < B1 < B1 + VW < B2 + VW < CA < CA + VW. Applying tested BC/CA and VW significantly increased chlorophyll compared to unamended soil. The outcomes revealed a substantial elevation in TE absorption in both shoot and root (p ≤ 0.05) with all tested treatments compared to the untreated soil (K). The combined application of CA and VW resulted in the most significant TE uptake of TEs at both the root and the shoot. Furthermore, adding CA or VW as a foliar spray enhanced the bioaccumulation factor (BCF) and translocation factor (TF) of studied metals. The combined addition of CA and foliar spraying of VW was more effective than the sole addition of CA or VW. Such increase reached 20.0%, 15.6%, 19.4%, 14.3%, 14.0%, and 25.6% of TF, and 13.7%, 11.9%, 8.3%, 20.9%, 20.5%,18.7%, and 19.8% of BCE for Cd, Cu, Fe, Mn, Ni, Pb, and Zn, respectively. This study highlights the efficiency of combining CA/BC with VW as a more viable option for remediating mine-contaminated soil than individual amendments. However, future research should prioritize long-term field trials to assess the efficiency of using citric acid and vermiwash for restoring contaminated mining soils.

The Rejuvenation Effect of Bio-Oils on Long-Term Aged Asphalt.

Generally, rejuvenators are used to supply missing components of aged asphalt, reverse the aging process, and are widely used in asphalt maintenance and recycling. However, compared with traditional rejuvenators, bio-oil rejuvenators are environmentally friendly, economical and efficient. This study looks into the effect of the three different bio-oils, namely sunflower oil, soybean oil, and palm oil, on the physical properties, rheological properties and chemical components of aged asphalt at different dosages. The asphalt physical properties and Dynamic Shear Rheological (DSR) test results show that with the increase in bio-oil, the physical properties and rheological properties of rejuvenated asphalt are close to those of virgin asphalt, but the high-temperature rutting resistance needs to be further improved. The results of Fourier Transform Infrared Spectroscopy (FTIR) show that the carbonyl and sulfoxide indices of rejuvenated asphalt are much lower than those of aged asphalt. Moreover, the rejuvenation efficiency of aged asphalt mixed with sunflower oil is better than that with soybean oil and palm oil at the same dosage.

Unusual vitamin E profile in the oil of a wild African oil palm tree (Elaeis guineensis Jacq.) enhances oxidative stability of provitamin A.

Introduction: The African oil palm (Elaeis guineensis Jacq.) is the predominant oil crop in the world. In addition to triacylglycerols, crude palm oil (CPO) extracted from the mesocarp of the fruits, contains high amounts of provitamin A (carotenes) and vitamin E (tocochromanols). Because of their unsaturated nature, the carotenes are prone to oxidation and therefore are in part limiting for the shelf life of CPO. Methods: A tree with unusual toochromanol composition was identified by HPLC screening of the mesocarp of wild trees. Polymorphisms in a candidate gene were identified by DNA sequencing. The candidate protein was heterologously expressed in Escherichia coli coli and Arabidopsis thaliana to test for enzyme activity. Oxidative stability of the CPO was studied by following carotene degradation over time. Results: In the present study, a wild Oil Palm tree (C59) from Cameroon was identified that lacks α-tocopherol and α-tocotrienol and instead accumulates the respective γ forms, suggesting that the activity of γ-tocopherol methyltransferase (VTE4) was affected. Sequencing of the VTE4 locus in the genome of plant C59 identified a G/C polymorphism that causes the exchange of a highly conserved tryptophan at position 290 with serine. The W290S exchange renders the VTE4 enzyme inactive, as shown after expression in Escherichia coli and Arabidopsis thaliana. The oxidative stability of carotenes in the mesocarp of the wild palm C59 was enhanced compared with control accessions. Furthermore, supplementation of commercial palm oil with different tocochromanols showed that γ-tocotrienol exerts a stronger effect during the protection of carotenes against oxidation than α-tocotrienol. Discussion: Therefore, the introduction of the high γ-tocotrienol trait into elite breeding lines represents a potent strategy to protect carotenes against oxidation and extend the shelf life of CPO, hence allowing the development of a value added high-carotene CPO to be used to fight against vitamin A deficiency.

A Circular Bioeconomy Approach to Using Post-Bioadsorbent Materials Intended for the Removal of Domestic Wastewater Contaminants as Potential Reinforcements.

Agro-industrial residue valorization under the umbrella of the circular bioeconomy (CBE) has prompted the search for further forward-thinking alternatives that encourage the mitigation of the industry's environmental footprint. From this perspective, second-life valorization (viz., thermoplastic composites) has been explored for agro-industrial waste (viz., oil palm empty fruit bunch fibers, OPEFBFs) that has already been used previously in other circular applications (viz., the removal of domestic wastewater contaminants). Particularly, this ongoing study evaluated the performance of raw residues (R-OPEFBFs) within three different size ranges (250-425, 425-600, 600-800 µm) both before and after their utilization in biofiltration processes (as post-adsorbents, P-OPEFBFs) to reinforce a polymer matrix of acrylic resin. The research examined the changes in R-OPEFBF composition and morphology caused by microorganisms in the biofilters and their impact on the mechanical properties of the composites. Smaller R-OPEFBFs (250-425 µm) demonstrated superior mechanical performance. Additionally, the composites with P-OPEFBFs displayed significant enhancements in their mechanical properties (3.9-40.3%) compared to those with R-OPEFBFs. The combination of the three fiber sizes improved the mechanical behavior of the composites, indicating the potential for both R-OPEFBFs and P-OPEFBFs as reinforcement materials in composite applications.

Enhancing Tensile Modulus of Polyurethane-Based Shape Memory Polymers for Wound Closure Applications through the Addition of Palm Oil.

Thermo-responsive, biocompatible polyurethane (PU) with shape memory properties is highly desirable for biomedical applications. An innovative approach to producing wound closure strips using shape memory polymers (SMPs) is of significant interest. In this work, PU composed of polycaprolactone (PCL) and 1,4-butanediol (BDO) was synthesized using two-step polymerization. Palm oil (PO) was added to PU for enhancing the Young's modulus of the PU beyond the set criterion of 130 MPa. It was found that PU had the ability to crystallize at room temperature and the segments of individual PCL and BDO polyurethanes crystallized separately. The crystalline domains and hard segment of PU greatly affected the tensile properties. The reduction of crystalline domains by the addition of PO and deformation at the higher melting temperature of the crystalline PCL polyurethane phase improved the shape fixity and shape recovery ratios. The new irreversible phase, raised from the permanent deformation upon stretching at the between melting temperature of the crystalline PCL and BDO polyurethanes of 70 °C, resulted in a decrease in shape fixity ratio after the first thermomechanical stretching-recovering cycles. The demonstration of PU as a wound closure strip showed its efficiency and potential until the surgical wound healed.

Loss of Sunda clouded leopards and forest integrity drive potential impacts of mesopredator release on vulnerable avifauna.

Amongst the unintended consequences of anthropogenic landscape conversion is declining apex predator abundance linked to loss of forest integrity, which can potentially re-order trophic networks. One such re-ordering, known as mesopredator release, occurs when medium-sized predators, also called mesopredators, rapidly increase in abundance following the decline in apex predator abundance, consequently reducing the abundance of mesopredator prey, notably including terrestrial avifauna. We examine the cascading impacts of declining Sunda clouded leopard abundance, itself consequent upon a reduction in forest integrity, on the mesopredator community of Sabah, Malaysia, to determine whether the phenomenon of mesopredator release is manifest and specifically whether it impacts the terrestrial avifauna community of pheasants and pittas. To explore this trophic interaction, we used a piecewise structural equation model to compare changes in the relative abundance of organisms. Our results suggest that loss of forest integrity may have broad impacts on the community and trigger mesopredator release, the two acting additively in their impact on already vulnerable species of terrestrial avifauna: a result not previously documented in tropical systems and rarely detected even on a global scale. The limiting effect that the Sunda clouded leopard has on the Sunda leopard cat could illuminate the mechanism whereby mesopredator release impacts this system. Both Bulwer's pheasant and pittas appear to be significantly impacted by the increase in Sunda leopard cats, while the great argus pheasant shows similar compelling, although not statistically significant, declines as Sunda leopard cats increase. The inverse relationship between Sunda clouded leopards and Sunda leopard cats suggests that if a mesopredator release exists it could have downstream consequences for some terrestrial avifauna. These results suggest the under-studied interface between mammalian carnivores and avifauna, or more broadly species interactions in general, could offer important conservation tool for holistic ecosystem conservation efforts.

Changes in serum lipids following consumption of coconut oil and palm olein oil: A sequential feeding crossover clinical trial.

BACKGROUND: High incidence of cardiovascular disease (CVD) in South Asia is linked to genetic predisposition and diets high in saturated fatty acids (SFAs). Increased CVD prevalence correlates with rising palm oil consumption in some South Asian countries, where coconut oil and palm olein oil are primary SFA sources. OBJECTIVE: Compare the effects of coconut oil and palm olein oil on serum lipoprotein lipids and biochemical parameters in healthy adults. METHODS: A sequential feeding crossover clinical trial with two feeding periods of 8 weeks each was conducted among 40 healthy adults. Participants were provided palm olein oil in the first feeding period followed by coconut oil with a 16-week washout period in between. The outcomes measured were the difference in serum low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C), TC/HDL-C ratio, triglycerides (TG), very-low-density lipoprotein cholesterol (VLDL-C), fasting plasma glucose (FPG), and liver enzymes. RESULTS: Thirty-seven participants completed the study. LDL-C decreased by 13.0 % with palm olein oil (p < 0.001) and increased by 5.6 % with coconut oil (p = 0.044), showing a significant difference (p < 0.001). TC decreased by 9.9 % with palm olein oil (p < 0.001) and increased by 4.0 % with coconut oil (p = 0.044). CONCLUSION: Palm olein oil consumption resulted in more favorable changes in lipid-related CVD risk factors (TC, LDL-C, TC:HDL-C, and FPG) compared to coconut oil. Clinical Trial Registry number and website where it was obtained: (SLCTR/2019/034); https://slctr.lk/trials/slctr-2019-034.

A lightweight CNN model for pepper leaf disease recognition in a human palm background.

The identification of pepper leaf diseases is crucial for ensuring the safety and quality of pepper yield. However, existing methods heavily rely on manual diagnosis, resulting in inefficiencies and inaccuracies. In this study, we propose a lightweight convolutional neural network (CNN) model for recognizing pepper leaf diseases and subsequently develop an application based on this model. To begin with, we acquired various images depicting healthy leaves as well as leaves affected by viral diseases, brown spots, and leaf mold. It is noteworthy that these images were captured against a background of human palms, which is commonly encountered in field conditions. The proposed CNN model adopts the GGM-VGG16 architecture, incorporating Ghost modules, global average pooling, and multi-scale convolution. Following training with the collected image dataset, the model was deployed on a mobile terminal, where an application for pepper leaf disease recognition was developed using Android Studio. Experimental results indicate that the proposed model achieved 100 % accuracy on images with a human palm background, while also demonstrating satisfactory performance on images with other backgrounds, achieving an accuracy of 87.38 %. Furthermore, the developed application has a compact size of only 12.84 MB and exhibits robust performance in recognizing pepper leaf diseases.

Efficiency enhancement of electrocoagulation, ion-exchange resin and reverse osmosis (RO) membrane filtration by prior organic precipitation for treatment of anaerobically-treated palm oil mill effluent.

Anaerobically-treated palm oil mill effluent (POME) still has unacceptable properties for water recycling and reuse, with an unpleasant appearance due to the brownish color caused by tannins and phenolic compounds. This study proposes an approach for treating anaerobically-treated POME for water recycling by combining organic precipitation, electrocoagulation (EC), and ion-exchange resin, followed by reverse osmosis (RO) membrane filtration in series. The results indicated that the organic precipitation enhanced the efficiency of EC treatment in reducing the concentrations of tannins, color, and chemical oxygen demand (COD) of the anaerobically-treated POME effluent, with reductions of 95.73%, 96.31%, and 93.96% for tannin, color, and COD, respectively. Moreover, organic precipitation affected the effectiveness of Ca2+ and Mg2+ ion removal using ion exchange resin and RO membrane filtration. Without prior organic precipitation, the ion-exchange resin process required a longer contact time, and the RO membrane filtration treatment was hardly effective in removing total dissolved solids (TDS). The combined process gave a water quality that meets the criteria set by the Thailand Ministry of Industry for industrial boiler use (COD 88 mg/L, TDS < 0.001 mg/L, water hardness < 5 mg-CaCO3/L, and pH 6.9).

Contribution of Malang quartzite-based silica in K2O/zeolite Y catalyst for methyl ester synthesis of off grade crude palm oil.

Malang quartzite contains a highly silica content. The silica changes the structural composition of Zeolite Y. Currently, a heterogeneous catalyst is developed to optimize transesterification of Off Grade CPO (Crude Palm Oil). The aims of this study are: (1) synthesize K2O/Zeolite Y using silica from Malang quartzite, (2) synthesize methyl esters from Off Grade CPO using K2O/Zeolite Y catalyst, and (3) to evaluate quartzite based-silica contribution in Zeolite Y for the reaction activity via GC-MS analysis. The experimental stages were: the oil preparation, esterification of the prepared oil, preparation of K2O/zeolite Y catalyst, and the transesterification. This study applied variations of [KOH] in Zeolite Y (10, 20, and 30 % w/w) and the concentration of the transesterification catalyst (2, 3, and 4 % w/w). The K2O/Zeolite Y catalyst was successfully synthesized by impregnation method. Methyl esters of Off Grade CPO resulted the highest yield of 95.05 % with 4 wt% of 30-K2O/Zeolite Y (30 % KOH impregnation). The synthesized methyl esters have a density of 0.877 g/mL, a viscosity of 4.6 cSt, a refractive index of 1.445 and an acid number of 0.384 mg/g according to the standard (SNI 7182:2015). The main components of the methyl ester based on GC-MS results were methyl octanoate, methyl decanoate, methyl dodecanoate, methyl 9-octadecanoate, methyl octadecanoate and methyl tetracosanoate. Using quartzite-based silica, a co-activity of the reaction has occurred.

Supplementation of date palm (Phoenix dactylifera L.) residue for growth and lactic acid production of probiotic bacterial Lactobacillus spp.

Date palm is an age-old cultivated plant that thrives in tropical and subtropical regions. The date palm is a bountiful source of carbohydrates, encompassing sucrose, glucose, and fructose and proteins. The date industry generates a significant volume of unused by-products. Dates offer a diverse range of by-products beyond the agri-food sector. LAB have garnered extensive utilisation across diverse food sectors, spanning meat, vegetables, beverages, dairy products, and other fermented foods. In the quest for establishing a new large-scale fermentation process for lactic acid there has been a concerted effort to utilise more cost-effective medium components. In the present work, date palm residue (DPR) derived from date palm fruit, after sugar extraction, was incorporated into MRS. The fermentation process was executed through two distinct fermentation systems. Initially, experiments were conducted in flasks. Afterward, the optimal conditions for bacterial growth were determined, and the experiment was carried out using a bioreactor. DPR supported the probiotic Lactobacillus spp. growth especially after 48 h incubation. The prebiotic effect of DPR on Lactobacillus spp. was reported. An increase in the total number of bacterial populations was observed in response to the addition the DPR until 48 h. Specifically, the supplementing DPR at a concentration of 1.5% in batch fermentation enhanced the growth and lactic acid production of Lactobacillus casei. This study suggests that DPR could potentially function as an economical prebiotic source and could be seamlessly incorporated as a functional food ingredient, thereby transforming a waste product into an economically sustainable food substrate.

Large-eddy simulation of aerosol concentrations in a realistic urban environment: Model validation and transport mechanism.

Air pollution in urban environments exhibits large spatial and temporal variations due to high heterogeneous air flow and emissions. To address the complexity of local air pollutant dynamics, a comprehensive large-eddy simulation using the PALM model system v6.0 was conducted. The distribution of flow and vehicle emitted aerosol particles in a realistic urban environment in Malmö, Sweden, was studied and evaluated against on-site measurements made using portable instrumentation on a spring morning in 2021. The canyon transport mechanisms were investigated, and the convective and turbulent mass-transport rates compared to clarify their role in aerosol transport. The horizontal distribution of aerosols showed acceptable evaluation metrics for both mass and number. Flow and pollutant concentrations were more complex than those in idealized street canyon networks. Vertical turbulent mass-transport rate was found to dominate the mass transport process compared with the convective transport rate, contributing more than 70% of the pollutant transport process. Our findings highlight the necessity of examining various aerosol metric due their distinct dispersion behaviour. This study introduces a comprehensive high-resolution modelling framework that accounts for dynamic meteorological and aerosol background boundary conditions, real-time traffic emission, and detailed building features, offering a robust toll for local urban air quality assessment.

Land in limbo: Nearly one third of Indonesia's cleared old-growth forests left idle.

Indonesia has experienced rapid primary forest loss, second only to Brazil in modern history. We examined the fates of Indonesian deforested areas, immediately after clearing and over time, to quantify deforestation drivers in Indonesia. Using time-series satellite data, we tracked degradation and clearing events in intact and degraded natural forests from 1991 to 2020, as well as land use trajectories after forest loss. While an estimated 7.8 Mha (SE = 0.4) of forest cleared during this period had been planted with oil palms by 2020, another 8.8 Mha (SE = 0.4) remained unused. Of the 28.4 Mha (SE = 0.7) deforested, over half were either initially left idle or experienced crop failure before a land use could be detected, and 44% remained unused for 5 y or more. A majority (54%) of these areas were cleared mechanically (not by escaped fires), and in cases where idle lands were eventually converted to productive uses, oil palm plantations were by far the most common outcome. The apparent deliberate creation of idle deforested land in Indonesia and subsequent conversion of idle areas to oil palm plantations indicates that speculation and land banking for palm oil substantially contribute to forest loss, although failed plantations could also contribute to this dynamic. We also found that in Sumatra, few lowland forests remained, suggesting that a lack of remaining forest appropriate for palm oil production, together with an extensive area of banked deforested land, may partially explain slowing forest loss in Indonesia in recent years.

Hybridization in palms (Arecaceae).

Hybridization has significant evolutionary consequences across the Tree of Life. The process of hybridization has played a major role in plant evolution and has contributed to species richness and trait variation. Since morphological traits are partially a product of their environment, there may be a link between hybridization and ecology. Plant hybrid species richness is noted to be higher in harsh environments, and we explore this hypothesis with a keystone tropical plant lineage, palms (Arecaceae). Leveraging a recent literature review of naturally occurring palm hybrids, we developed a method to calculate hybrid frequency, and then tested if there is phylogenetic signal of hybrids using a phylogeny of all palms. Further, we used phylogenetic comparative methods to examine the interaction between hybrid frequency and presence in dry environments, on islands, and the species richness of genera. Phylogenetic generalized least squares models had stronger support than models of random association, indicating phylogenetic signal for the presence of hybrids in dry and island environments. However, all p-values were >.05 and therefore the correlation was poor between hybridization and the trait frequencies examined. Presence in particular environments are not strongly correlated to hybrid frequency, but phylogenetic signal suggests a role in its distribution in different habitats. Hybridization in palms is not evenly distributed across subfamilies, tribes, subtribes yet plays an important role in palm diversity, nonetheless. Increasing our understanding hybridization in this economically and culturally important plant family is essential, particularly since rates are projected to increase with climate change, reconfiguring the dynamics and distribution of biodiversity.

Silencing sensory neuron membrane protein RferSNMPu1 impairs pheromone detection in the invasive Asian Palm Weevil.

The red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier), also known as the Asian palm weevil, is an invasive pest that causes widespread damage to palm trees around the globe. As pheromone communication is crucial for their mass attack and survival on palm trees, the olfactory concept of pest control strategies has been widely explored recently. We aim to understand the molecular basis of olfaction in RPW by studying one of the key olfactory proteins in insect pheromone communication, sensory neuron membrane proteins (SNMPs). SNMPs belong to the CD36 (cluster of differentiation 36) family that perform two distinct olfactory roles in insects, either in pheromone (odorant) transfer to the odorant receptors (SNMP1) or in the pheromone clearing process (SNMP2). In this study, we performed antennal transcriptomic screening and identified six SNMPs, mapping them on the R. ferrugineus genome, and confirmed four distinct SNMPs. Both SNMP1 proteins in RPW, viz., RferSNMPu1 and RferSNMPu2, were mapped onto the same scaffold in different loci in the RPW genome. To further understand the function of these proteins, we first classified them using phylogenetic analysis and checked their tissue-specific expression patterns. Further, we measured the relative transcript abundance of SNMPs in laboratory-reared, field-collected adults and pheromone-exposure experiments, ultimately identifying RferSNMPu1 as a potential candidate for functional analysis. We mapped RferSNMPu1 expression in the antennae and found that expression patterns were similar in both sexes. We used RNAi-based gene silencing to knockdown RferSNMPu1 and tested the changes in the RPW responses to aggregation pheromone compounds, 4-methyl-5-nonanol (ferrugineol) and 4-methyl-5-nonanone (ferrugineone), and a kairomone, ethyl acetate using electroantennogram (EAG) recordings. We found a significant reduction in the EAG recordings in the RferSNMPu1 knockdown strain of adult RPWs, confirming its potential role in pheromone detection. The structural modelling revealed the key domains in the RferSNMPu1 structure, which could likely be involved in pheromone detection based on the identified ectodomain tunnels. Our studies on RferSNMPu1 with a putative role in pheromone detection provide valuable insight into understanding the olfaction in R. ferrugineus as well as in other Curculionids, as SNMPs are under-explored in terms of its functional role in insect olfaction. Most importantly, RferSNMPu1 can be used as a potential target for the olfactory communication disruption in the R. ferrugineus control strategies.

Synthesis of hydrochar from date palm seeds using microwave-enhanced hydrothermal carbonization and its application in dyes removal.

This work reports new findings on the preparation of hydrochar from date palm (Phoenix dactylifera) seeds through the application of the microwave hydrothermal carbonization (HTC) method. Optimization investigations involving temperatures and reaction times were conducted to establish the highest yield, achieving a maximum yield of 60.87%. The prepared material was then impregnated in phosphoric acid and carbonized in the tube furnace at 550 °C for 1.5 h with a nitrogen flow of 50 CCM. The samples were characterized via scanning electron microscopy (SEM), Brunauer-Emmet-Teller (BET) and Fourier transform infrared (FTIR). The samples showed remarkable BET surface areas following activation, reaching up to 992 m2·g-1. The substance was subsequently used to absorb methylene blue with good fitting to the Freundlich and Redlich-Peterson isotherm and achieved a peak adsorption capacity of 196.6 ± 3.9 mg·g-1.

This study involves the preparation of hydrochar through microwave-assisted hydrothermal carbonization (HTC) of date palm seeds. It explores the impact of different process parameters, such as power, reaction temperatures, and timing on the mass yield and BET surface area of the hydrochars. Additionally, the prepared material undergoes chemical activation with phosphoric acid, and its efficacy in extracting methylene blue (MB) from an aqueous solution is assessed. This research is particularly novel as it represents the first comprehensive investigation into the use of microwave-derived and phosphoric acid-activated hydrochar for MB extraction.

Growth and population structure of Lodoicea maldivica in natural stands in Seychelles.

We monitored leaf production in seedlings, trunkless juvenile, immature, and mature male and female plants of the dioecious palm, Lodoicea maldivica, and studied how internode length changed with trunk height. The fieldwork was conducted in closed forest on Praslin Island and degraded forest on Curieuse Island. Data on numbers of leaves produced and rates of leaf production were used to estimate plant age. On Praslin, the interval between successive leaves increased from 0.47/0.52 years in male/female plants to 4.2 years in seedlings, and on Curieuse from 0.41/0.49 to 2.3 years. Estimated leaf lifespan was 6.4-6.8 years in mature palms and much longer in seedlings and juveniles. On Praslin, internode length increased from the base of the trunk to a mean of 14 cm at leaf 21, before declining to 2.75 cm above leaf 100. Mean internode length of the smaller palms on Curieuse was 1.9 cm and varied little with height. Plants at the same development stage varied widely in age. On Praslin, median time to maturity was 77 (range: 32-209) and on Curieuse 83 (31-191) years. The tallest palms on Praslin (28.4 m trunk height) and Curieuse (8 m) were estimated at 442 and 232 years old, respectively. The ageing method was used to interpret height data of different populations. All showed a marked decline in regeneration in the 19th or early 20th centuries, probably caused by fires. We conclude that slow growth makes this species very vulnerable to disturbance, especially from fire.

Investigating process parameters to enhance (hemi)cellulolytic enzymes activity produced by Trichoderma reesei RUT-C30 using deoiled oil palm mesocarp fiber in solid-state fermentation.

This study investigates the synthesis of (hemi)cellulolytic enzymes, including endoglucanase (CMCase), xylanase, and ß-glucosidase, employing Trichoderma reesei RUT-C30 and deoiled oil palm mesocarp fiber (OPMF) through solid-state fermentation (SSF). The objective was to determine the optimal process conditions for achieving high enzyme activities through a one-factor-at-a-time approach. The study primarily focused on the impact of the solid-to-liquid ratio, incubation period, initial pH, and temperature on enzyme activity. The effects of OPMF pretreatment, particularly deoiling and fortification, were explored. This approach significantly improved enzyme activity levels compared to the initial conditions, with CMCase increasing by 111.6 %, xylanase by 665.2 %, and ß-Glucosidase by 1678.1 %. Xylanase and ß-glucosidase activities, peaking at 1346.75 and 9.89 IU per gram dry substrate (GDS), respectively, under optimized conditions (1:4 ratio, pH 7.5, 20 °C, 9-day incubation). With lower moisture levels, CMCase reached its maximum activity of 227.84 IU/GDS. The study highlights how important it is for agro-industrial byproducts to support environmentally sustainable practices in the palm oil industry. It also emphasizes how differently each enzyme reacts to changes in process parameters.

Bioprospecting Study of Plant Growth Promoting Rhizospheric Bacteria from Oil Palm Plantation as Biological Control Agent of Ganoderma boninense.

<b>Background and Objective:</b> The prioritisation of oil palm studies involves the exploration of novel bacterial isolates as possible agents for suppressing <i>Ganoderma boninense</i>. The objective of this study was to evaluate and characterise the potential of rhizospheric bacteria, obtained from the rhizosphere of oil palm plants, in terms of their ability to demonstrate anti-<i>Ganoderma </i>activity. <b>Materials and Methods:</b> The study began by employing a dual culture technique to select hostile bacteria. Qualitative detection was performed to assess the antifungal activity, as well as the synthesis of chitinase and glucanase, from certain isolates. The candidate strains were molecularly identified using 16S-rRNA ribosomal primers, specifically the 27F and 1492R primers. <b>Results:</b> The findings of the study indicated that the governmental plantation exhibited the highest ratio between diazotroph and indigenous bacterial populations in comparison to the other sites. Out of a pool of ninety bacterial isolates, a subset of twenty-one isolates demonstrated the ability to impede the development of <i>G. boninense</i>, as determined using a dual culture experiment. Twenty-one bacterial strains were found to exhibit antifungal activity. Nine possible bacteria were found based on the sequence analysis. These bacteria include <i>Burkholderia territorii</i> (RK2, RP2, RP3, RP5), <i>Burkholderia stagnalis</i> (RK3), <i>Burkholderia cenocepacia</i> (RP1), <i>Serratia marcescens</i> (RP13) and <i>Rhizobium multihospitium</i> (RU4). <b>Conclusion:</b> The findings of the study revealed that a significant proportion of the bacterial population exhibited the ability to perform nitrogen fixation, indole-3-acetic acid (IAA) production and phosphate solubilization. However, it is worth noting that <i>Rhizobium multihospitium</i> RU4 did not demonstrate the capacity for phosphate solubilization, while <i>B. territory</i> RK2 did not exhibit IAA production.