Biodegradation Process Research Articles

Proteome Changes Induced by Iprodione Exposure in the Pesticide-Tolerant Pseudomonas sp. C9 Strain Isolated from a Biopurification System

Iprodione is a pesticide that belongs to the dicarboximide fungicide family. This pesticide was designed to combat various agronomical pests; however, its use has been restricted due to its environmental toxicity and risks to human health. In this study, we explored the proteomic changes in the Pseudomonas sp. C9 strain when exposed to iprodione, to gain insights into the affected metabolic pathways and enzymes involved in iprodione tolerance and biodegradation processes. As a result, we identified 1472 differentially expressed proteins in response to iprodione exposure, with 978 proteins showing significant variations. We observed that the C9 strain upregulated the expression of efflux pumps, enhancing its tolerance to iprodione and other harmful compounds. Peptidoglycan-binding proteins LysM, glutamine amidotransferase, and protein Ddl were similarly upregulated, indicating their potential role in altering and preserving bacterial cell wall structure, thereby enhancing tolerance. We also observed the presence of hydrolases and amidohydrolases, essential enzymes for iprodione biodegradation. Furthermore, the exclusive identification of ABC transporters and multidrug efflux complexes among proteins present only during iprodione exposure suggests potential counteraction against the inhibitory effects of iprodione on downregulated proteins. These findings provide new insights into iprodione tolerance and biodegradation by the Pseudomonas sp. C9 strain.

Maximizing diclofenac bioremoval efficiency using Chlorella vulgaris strain H1 and Chlorella sorokiniana strain H2: Unveiling the impact of acetic acid on microalgae

BackgroundDiclofenac (DFC) is a commonly detected pharmaceutical pollutant in wastewater, posing environmental risks. Microalgae have emerged as potential candidates for bioremediation due to their ability to degrade pollutants. This study focuses on investigating the biodegradation potential of two newly isolated microalgae strains, Chlorella vulgaris strain H1 and Chlorella sorokiniana strain H2, towards DFC removal. The optimization of pH is crucial for enhancing the efficiency of bioremediation processes. Therefore, in addition to assessing the biodegradation potential of microalgae, this study also investigates the impact of adjusting the pH of the culture medium using acetic acid as an additional carbon source on the biodegradation process. MethodsThrough genetic analysis using 18S rDNA sequencing, the microalgae strains were identified. Various parameters including growth dynamics, chlorophyll content, cell proliferation, photosynthetic activity, and DFC biodegradation efficiency were comprehensively assessed. Additionally, the impact of incorporating acetic acid as an additional carbon source in the culture medium on the biodegradation process was examined. Significant FindingsC. sorokiniana strain H2 demonstrated superior biodegradation rates compared to C. vulgaris strain H1 across varying DFC concentrations. Specifically, C. sorokiniana strain H2 exhibited remarkable biodegradation rates of 84 %, 83.72 %, and 29.57 % for DFC concentrations of 12.5 mg L−1, 25 mg L−1, and 100 mg L−1, respectively. In contrast, C. vulgaris strain H1 showed lower biodegradation rates of 66.64 %, 29.24 %, and 1.83 % for the corresponding DFC concentrations. The study highlights the potential of C. sorokiniana strain H2 as a promising candidate for the removal of pharmaceutical pollutants like DFC from wastewater. Furthermore, the use of acetic acid as a supplementary carbon source enhanced the biodegradation efficiency, suggesting a potential strategy for optimizing bioremediation processes.

Evaluating the removal of the tetra-azo dye direct black-22 in Chlorella vulgaris closed-cultivation systems

ABSTRACT The removal of the tetra-azo dye Direct Black 22 (DB22) using the microalga Chlorella vulgaris was evaluated in the present study, aiming to understand the contribution of different processes (biodegradation, photodegradation, and adsorption) in the removal of this contaminant. The growth and morphological characteristics of C. vulgaris were not affected by the presence of the dye in the reaction medium. The efficiency of dye removal was 62.6 ± 1.46%, 47.7 ± 7.2% of which was attributed to photodegradation, while 13.2 ± 6.5% were associated with the contribution of the microalga by an enzymatic route and 1.7 ± 9.6% with an adsorption process. Additionally, tests with the organism Allium cepa as a bioindicator revealed that DB22 and its byproducts did not induce toxicity, but cytotoxicity and genotoxicity were induced. We observed that genotoxicity was reduced after the remediation process. Our results establish photodegradation as the primary mechanism and biodegradation as the secondary mechanism driving the removal of DB22 within a Chlorella culture. Researchers must carefully consider all aspects involved in the removal process, including photodegradation, biodegradation, and adsorption processes.

Impacts of post-operation loading and fixation implant on the healing process of fractured tibia.

Healing of tibia demonstrates a complex mechanobiological process as it is stimulated by the major factor of strains applied by body weight. The effect of screw heads and bodies as well as their pressure distribution is often overlooked. Hence, effective mechanical conditions of the healing process of tibia can be categorized into the material of the plate and screws, post-operation loadings, and screw type and pressure. In this paper, a mathematical biodegradation model was used to simulate the PGF/PLA plate-screw device over 8 weeks. The effect of different post-operation loading patterns was studied for both locking and non-locking screws. The aim was to reach the best configuration for the most achievable healing using FEA by computing the healing pattern, trend, and efficiency with the mechano-regulation theory based on deviatoric strain. The biodegradation process of the plate and screws resulted in 82% molecular weight loss and 1.05 GPa decrease in Young's modulus during 8 weeks. The healing efficiency of the cases ranged from 4.72% to 14.75% in the first week and 18.64% to 63.05% in the eighth week. Finally, an optimal case was achieved by considering the prevention of muscle erosion, bone density reduction, and nonunion, according to the obtained results.

Biodegradation of thermoplastic starch by a newly isolated active microbial community: Deciphering the biochemical mechanisms controlling bioprocess robustness

Defining sustainable end-of-life routes for bioplastics comprises a task of outmost importance, while biological recycling constitutes the most favorable option for several biopolymers, such as thermoplastic starch (TPS). To our knowledge, this is the first study to assess the biodegradation of TPS pellets and films in aqueous cultures employing an acclimated microbial community. Biological treatment of bioplastics displayed a two-phase pattern that included different biodegradation rates, where TPS removal in the first phase remained high and decelerated in the second phase reaching a plateau. Thus, TPS weight reduction of 14.8 % was observed using pellets following 10 d of incubation, while although films exhibited higher reduction (slightly over 30 % in 15 d), the biodegradation rate was significantly reduced thereafter. Several changes of starch related bands were detected (using FTIR) in the surface of both pellets and films during the bioprocess, indicating induction of a common biodegradation pathway. Distinct bacterial assemblages were formed during the TPS biodegradation process and statistically significant differences were detected in the abundance of several genera between the two degradation phases. Fungal communities were more stable (Fusarium and Neocosmospora were dominant at all times) and there was no effect of biofilm or degradation phase on fungal community composition. Overall, a more diverse community incorporating lower catalytic activity was gradually formed, as confirmed by the shift between k-stategist and r-stategist taxa monitored, while crystalline over amorphous regions were enhanced in the biopolymer during TPS biodegradation, responses consistent with the biodegradation rate reduction observed in the plateau stage. The study highlighted the biochemical mechanism limiting TPS biodegradation processes and the significant potential of the newly isolated community in the development of TPS waste treatment technologies.

The Ultimate Fate of Reactive Dyes Absorbed onto Polymer Beads: Feasibility and Optimization of Sorbent Bio-Regeneration under Alternated Anaerobic–Aerobic Phases

Dyes employed in many production cycles are characterized by high toxicity and persistence in the environment, and conventional wastewater treatments often fail to reach high removal efficiencies. Consequently, there is an increasing research demand aimed at the development of more efficient and sustainable technologies. A two-step strategy consisting of dye sorption followed by sorbent bio-regeneration is proposed here, with a special focus on the regeneration step. The objective of this study was to establish the best operating conditions to achieve regeneration of dye-loaded polymers and concurrently the ultimate removal of the dyes. To this aim, the bio-regeneration of the Hytrel 8206 polymer, used as a sorbent material to remove Remazol Red dye from textile wastewater, was investigated in a two-phase partitioning bioreactor (TPPB) under alternated anaerobic–aerobic conditions. Comprehensive analysis of operational parameters, including sorbent load and initial contamination levels, was conducted to optimize bio-regeneration efficiency. Experimental data demonstrated high regeneration efficiencies (91–98%) with biodegradation efficiencies up to 89%. This study also examines the biodegradation process to investigate the fate of biodegradation intermediates; results confirmed the successful degradation of the dye without significant by-product accumulation. This research underscores the potential of TPPB-based bio-regeneration of polymeric sorbent material for sustainable wastewater treatment, offering a promising solution to the global challenge of dye pollution in water resources.

Dissolution and intrusion of chloride disrupted biodegradation products to persistently accelerate biodegradation of Fe-based implants

The biodegradation of Fe is severely limited due to barrier of biodegradation products. Herein, NaCl was introduced into Fe matrix and results demonstrated that NaCl significantly accelerated biodegradation rate of Fe. It was ascribed that (i) NaCl in Fe matrix initially dissolved to produce biodegradation active sites, (ii) Cl- with small ionic radii invaded the biodegradation product layer, and (iii) abundant Cl- greatly promoted the anode process of Fe biodegradation. Additionally, Fe-NaCl biocomposites also exhibited favorite cytocompatibility. These results demonstrated great potential of NaCl in accelerating the persistent biodegradation of Fe for load-bearing implants.

Biodegradation of Spent Automobile Engine Oil in Soil Microcosms Amended with Coconut Shell

Food insecurity and low yield have resulted from the detrimental effects of petroleum hydrocarbon pollution on agricultural soils over time. This study was carried out to determine the bioremediation efficacy of coconut shell on microbiological composition and total petroleum hydrocarbon degradation in spent engine oil polluted soil. Top soil (0-15 cm depth) samples were randomly collected from areas with history of spent engine oil pollution within Anyigba, Kogi State, Nigeria. One kilogram of the polluted-soil was measured into each of nine plastic containers. Coconut shell collected from the Prince Abubakar Audu University, Anyigba, was standardly prepared and mixed with the soil at the rate of 0, 50 and 100 g kg-1 soil in triplicate. The experiment used a completely randomized design. Soil samples were taken from each container at 0 and 28 days for hydrocarbon utilizing bacteria and total petroleum hydrocarbon determination using standard methods. Data obtained from the experiment were subjected to descriptive and inferential statistics. The species identified were Enterobacter sp and Escherichia coli, with Enterobacter sp being the most predominant isolate. The total petroleum hydrocarbon (mgkg-1) of the soil on day 0 was 59.78 ± 1.85. After the amendments (at control, 50 and 100 g kg-1), the total petroleum hydrocarbon (mgkg-1) values were 44.92 ±2.26, 34.82 ± 1.78 and 31.49 ± 0.87 at 28 days respectively. Coconut shell and the high level carbon utilizing bacteria, Enterobacter sp, significantly enhanced the biodegradation process as an impressive 47.32% remediation efficiency was achieved 28 days after amendment in soil treated with 100g of coconut shell. It is recommended that a biostimulation strategy that uses coconut shell and Enterobacter sp be employed in the remediation of spent engine oil and petroleum hydrocarbon polluted soils.

Real time control of stormwater biofilters improves the removal of organic chemicals

Biofilters are among the most popular nature-based systems for treating stormwater and delivering multiple environmental benefits. However, as a passive system, their performance tends to be inconsistent in removing emerging organic contaminants produced by anthropogenic activities that can be persistent, mobile, and toxic. Thus, in this study, real time control (RTC) of stormwater biofilters is introduced to enhance the removal of a diverse range of organic chemicals. Laboratory columns were employed to investigate the performance of five RTC strategies, i.e., dynamic soil moisture control (RTC-Moisture), infiltration rate control (RTC-IR), pre-drain (RTC-PreDrain), fully unsaturated (RTC-UnSat), and fully saturated (RTC-FulSat). These RTC strategies were tested under varying rainfall sizes, as well as dry and wet conditions. Additionally, the study examined the accumulation of organic chemicals in the media. The results revealed that RTC-Moisture, RTC-IR, and RTC-PreDrain were the top three performing strategies, which achieved a significantly higher removal rate than Non-RTC biofilters for the majority of tested organic chemicals (p-value < 0.05). The best RTC strategy, RTC-Moisture, not only had the highest overall performance (average removal rate of 76.1 %) but was also least affected by various rainfall events. Despite a better chemical removal found in RTC-Moisture and RTC-PreDrain, there was no significant overall increase in the accumulation of organic chemicals within the media (p-value > 0.05) when compared to Non-RTC biofilters. This may indicate that the biodegradation process could be promoted in the well-performing RTC biofilters. This study confirms the possibility of using RTC strategies to enhance organic chemical removal in stormwater biofilters.

Sustainable Biopolymer Composites From Perlite, Plasticized and Unplasticized Poly(Lactic Acid)

In recent years, ecological pollution has reached critical levels and that has been experienced as climate change by all living organisms. Slowing down the negative effects of climate change depends on changing our consumption behavior. Based on that, people tend to prefer more environmentally friendly, sustainable raw materials, products and processes. Since polymers are one of the most widely used raw materials in the world, any improvement regarding their recycling or biodegradation process can significantly reduce the damage to nature. Considering this fact, manufacturers are taking initiatives to develop such products in line with the demand from consumers. As known, Poly(lactic acid) (PLA), one of the most consumed biodegradable polymers in the market, however there are various problems especially in film production due to its rigid structure. Plasticization is the easiest route to minimize this disadvantage. The aim of this study is to produce and characterize PLA composites with increased flexibility by using sustainable natural materials. In this context, glycerol-plasticized PLA and unplasticized PLA composites were prepared using perlite, a natural additive, and their morphological, thermal, and mechanical properties were investigated.

Insights into the biodegradation process of 2,4,5-trichlorophenoxyacetic acid under anaerobic condition

BackgroundChlorophenoxy compounds represent a group of selective herbicides widely used around the world. Chlorophenoxy herbicides are toxic, chemically stable, and can migrate into groundwater through soil leaching, posing a significant threat to drinking water safety and human health. Chlorophenoxy herbicides in groundwater aquifers are subject to anaerobic processes; however, the pathway and microbiology involved in the attenuation of chlorophenoxy herbicides under anaerobic condition are largely unknown. Here, the anaerobic degradation process of 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), a typical chlorophenoxy herbicide, was investigated.ResultsThe initial 52.5 ± 2.3 μM 2,4,5-T was completely degraded by a sediment-derived microbial consortium, with 3,4-dichlorophenol, 2,5-dichlorophenol, 3-chlorophenol (3-CP) and phenol being identified as the intermediate products. Reductive dechlorination of 3-CP to phenol and the subsequent elimination of phenol were the key transformation steps in the overall degradation process of 2,4,5-T. Amplicon sequencing suggested that Dehalobacter, Sulfuricurvum, Bacteroides, Acetobacterium, and Clostridium sensu stricto 7 might contribute to the transformation of 2,4,5-T to phenol, and Smithella, Syntrophorhabdus, Methanofollis and Methanosaeta likely cooperated to accomplish the complete mineralization of phenol.ConclusionsThis study reported the anaerobic degradation of 2,4,5-T via reductive dechlorination and the subsequent syntrophic metabolization of phenol, an intermediate product transformed from 2,4,5-T. Dehalobacter was identified as the organohalide-respiring population catalyzing the reductive dechlorination reaction. Syntrophorhabdus and methanogenic populations were likely involved in anaerobic phenol oxidation and facilitated the complete mineralization of 2,4,5-T.

Methyl Red degradation by a subseafloor fungus Schizophyllum commune 15R-5-F01: efficiency, pathway, and product toxicity.

Synthetic dyes pose a significant environmental threat due to their complex structures and resistance to microbial degradation. S. commune 15R-5-F01 exhibited over 96% degradation efficiency of Methyl Red in a medium with 100 mg L-1 Methyl Red within 3 h. The fungus demonstrated adaptability to various environmental conditions, including different pH levels, temperatures, oxygen concentrations, salinity, and heavy metals. S. commune 15R-5-F01 is capable of achieving repeated cycles of Methyl Red reduction with sustained degradation duration minimum of 6 cycles. It showed a maximum Methyl Red biodegradation capacity of at least 558 mg g-1 dry mycelia and a bioadsorption capacity of 57 mg g-1. Gas chromatography-mass spectrometry analysis confirmed the azo reduction of Methyl Red into N,N-dimethyl-p-phenylenediamine and 2-aminobenzoic acid. Enzymatic activity assays indicated the involvement of lignin peroxidases, laccases, and manganese peroxidase in the biodegradation process. Phytotoxicity tests on Triticum eastivum, Oryza sativa, and Vigna umbellata seeds revealed reduced toxicity of the degradation products compared to Methyl Red. This study identifies S. commune 15R-5-F01 as a viable candidate for the sustainable degradation of synthetic dyes in industrial wastewater.

Rapid parameter estimation of modified Gompertz and Logistic model for analyzing the growth of Escherichia Coli K2

Bacteria are living microorganisms that play an essential role in the biodegradation process. They can break down and detoxify harmful substances, thereby mitigating environmental contamination through natural means. The Gompertz and Logistic models are two growth models commonly utilized to examine population growth in biological systems. In this study, we have modified these models to investigate the growth of Escherichia Coli K2 bacteria. The mathematical parameters have been substituted with biologically meaningful parameters, and five new estimation methods have been introduced to evaluate the model parameters using standard growth data for E. Coli K2. The best method is selected based on a standardized criterion used in this study. The proposed methods demonstrate strong performance, and the estimated parameters are both logically coherent and biologically relevant.

Hybrid packed bed bioreactor using combined biodegradation and ozonation to enhance nitrogen and micropollutants removal from landfill leachate

Landfill leachate contains ammonium and micropollutants. Ammonium can be biologically removed but bio-recalcitrant micropollutants removal requires post-treatment like ozonation. This study developed an expanded clay aggregates packed biofilm column (EBC) and demonstrated its feasibility of coupling biodegradation and ozonation (CBAO) to simultaneously remove nitrogen and bio-recalcitrant micropollutants. The first 60 days only had biodegradation process to start the bioreactor. 51 % nitrogen was biologically removed but the removal of micropollutant carbamazepine (CBZ) was only 30 %. From 61 d to 150 d, both biodegradation and ozonation were performed in the EBC. After 48 h-biodegradation, ozone gas was introduced and bubbling through EBC for 30 min to further remove residual micropollutants. At 0.4 gO3/gCOD, CBZ were completely removed. The average nitrogen removal efficiency (85 %) was increased by 34 % because the increased abundance of nitrifying and denitrifying bacteria in EBC. This study confirmed the promising potential of the CBAO process for treating landfill leachte.

Influence of Aeration, Introduction of Probiotics, and Supply of Water on Landfill Gas Production—Study of Models

When municipal solid waste (MSW) is placed in a landfill, it undergoes anaerobic decomposition, leading to the production of landfill gas, which primarily consists of methane (CH4) and carbon dioxide (CO2). Reducing methane emissions is essential in the fight against climate change. It must be implemented at global and European levels, as set out in 2030 in the impact assessment of the climate goal plan. This assessment states that to achieve the goal by 2030 and to reduce greenhouse gas emissions by at least 55%, the methane emissions must be reduced, considering the goals of the Paris Agreement. The Glasgow Climate Pact includes a global mitigation target of the year 2030: to reduce CO2 emissions by 45%, and the emissions of methane and other greenhouse gasses. For that purpose, looking for new, more advanced ways of managing such waste is necessary. The main objective of this experimental study was to evaluate the influence of aeration, probiotic introduction, and water supply on the production of landfill gasses (CO2, CH4, N2, H2, etc.) in five different landfill models during the management of MSW and to propose the best solutions for reducing environmental pollution. The results of the research showed that the first and second models of landfills, using only anaerobic conditions, can be used for the treatment of MSW for the production of biogas (CH4, CO2), as up to 40–60% of it was released during the 120-experiment period. The third landfill model can be applied in old, already closed landfills, where the rapid stabilization and aeration of MSW are required to minimize pollutant emissions (N2, etc.) and unwanted odors and shorten biodegradation processes. The results of the fourth and fifth landfill models, in which aerobic–anaerobic conditions were applied, showed that the developing nitrification–denitrification processes resulted in complete nitrogen removal (from 20% to 0%), and overall waste stabilization improved the biodegradation of the MSW. Later, relatively good (on average, 30%) results of biogas (CH4, CO2) emissions are achieved during anaerobic condition formation results. Summarizing all experiment results of all landfill models for the further evaluation of the processes, all models can be applied in real practice depending on where they will be used and what result they want to achieve.

Comprehensive Understanding on the Aging Process and Mechanism of Microplastics in the Sediment-Water Interface: Untangling the Role of Photoaging and Biodegradation.

Microplastics (MPs) in coastal wetlands have been of great concern, but information on the aging behavior of MPs in the sediment-water interface is still lacking. In this study, the contribution of a typical abiotic (photoaging) and biotic (biodegradation) process and the underlying aging pathway of MPs with different degradabilities (including polypropylene, polyethylene terephthalate, and polylactic acid) were studied. With a quantified relative importance of photoaging (>55%) vs biodegradation, the crucial contribution of photoaging on MP aging was highlighted. This was likely attributed to more generation of reactive oxygen species (ROS) under sunlight irradiation conditions, containing O2•- and H2O2. By raising higher the level of malondialdehyde (0.5-3.5 times as high as that in the dark condition), these photochemically formed ROS caused oxidative stress and inhibited the selective attachment of plastic-degrading microbes on the MP surface, thereby weakening the effect of biodegradation. On this basis, the aging characteristics and potential pathway of different MPs were revealed. The functional group of nondegradable polypropylene tends to be broken by ROS first, while biodegradation (Arthrobacter oryzae and Bacillus sp.) played a relatively dominant role in biodegradable polylactic acid. This study provides a new sight for the understanding on the aging behaviors of MPs in the sediment-water interface.

An Assessment of Biodegradability and Phytotoxicity of Natural Rubber in a Simulated Soil Condition via CO2 Evolution Measurement.

In this study, the biodegradation of various natural rubber (NR) samples, i.e., neat NR and NR filled with two different curative contents was investigated under a long-term simulated soil condition at a temperature of 25 ± 2 °C in accordance with ISO 17556. Natural clay loam soil, with a pH of 7.2 and a water holding capacity of 57.6%, was employed. Under controlled test condition both unvulcanized and vulcanized NR samples having low curative content, respectively designated as UNRL and VNRL, exhibited similar biodegradation behaviors to the neat NR. They showed fast biodegradation at the early stage, and their biodegradation rate did not significantly change throughout the test period (365 days). However, for the NR samples having high curative content, respectively called UNRH and VNRH for the unvulcanized and vulcanized samples, a biodegradation delay was observed within the first 130 days. Surprisingly, the UNRH showed a relatively high biodegradation rate after the induction period. At the end of the test, most of the rubber samples (the neat NR, UNRL, VNRL, and UNRH) showed a comparable degree of biodegradation, with a value ranging from 54-59%. The VNRH, on the other hand, showed the lowest degree of biodegradation (ca. 28%). The results indicate that the number of curatives does not significantly affect the biodegradability of unvulcanized NR in the long term, despite the fact that a high curative content might retard microorganism activity at the beginning of the biodegradation process. Apparently, crosslink density is one of the key factors governing the biodegradability of NR. The phytotoxicity of the soils after the biodegradation test was also assessed and represented in terms of seedling emergence, survival rate, and plant biomass for Sorghum bicolor. The values of seedling emergence (≥80%), survival rate (100%), and plant biomass of all soil samples were not statistically different from those of the blank soil, indicating the low phytotoxicity of the tested soils subjected to the biodegradation of the rubber samples. Taken as a whole, it can be concluded that the CO2 measurement technique is one of the most effective methods to assess the biodegradability of rubbers. The knowledge obtained from this study can also be applied to formulate more environmentally friendly rubber products.

Mycelial growth, yield and decomposition capability of white oyster mushroom (Pleurotus florida) grown in low-density polyethylene (LDPE) plastic and lignocellulosic wastes

White Oyster Mushroom (Pleurotus florida) is one of the domesticated mushrooms in the Philippines and known to grow in various biodegradable wastes. Low Density Polyethelene (LDPE) plastic is one of the most common non-biodegradable wastes in the environment which causes pollution. At present, biodegradation process is one of the ways to degrade plastics because of its non-polluting mechanism and cost-effectiveness. Thus, this study aimed to determine if P. florida could grow in LDPE plastic and facilitate its decomposition. Fourteen treatments were used in the study, laid out in Complete Randomized Design, and replicated thrice. The first four (4) treatments were composed of substrates with no LDPE plastics (rice straw, sawdust and cocopeat) while the rests were substrates with certain percentage of LDPE plastics. Observation was done for eight (8) weeks in the PUP Lopez Mushroom Laboratory and the data obtained was analyzed using ANOVA. Result shows that slight decomposition happened in LDPE plastic mixed with lingo-cellulosic wastes. Small spots or dark holes appear in the surface of LDPE plastics observed under microscope which is a sign of decomposition. In terms of mycelial ramification, fruiting bags with LDPE plastics were first to occupy the fruiting bag. There was also a decreased weight of the fruiting bags after 8 weeks. In terms of yield, substrates without LDPE plastics grew mushrooms with the highest weight. However, yield in sawdust and cocopeat substrates were not significantly different with the yield of mushrooms grown in substrates with LDPE plastics.

Integrating enhanced biological phosphorus removal in adsorption-stage to treat real domestic sewage

Wastewater treatment innovation toward resource recovery facilities raises concerns about the adsorption and bio-degradation (A-B) process. This study integrated enhanced biological phosphorus removal (EBPR) into the A-stage for real domestic sewage treatment using the short sludge retention time (S-SRT) approach. The S-SRT approach resulted in outstanding phosphorus (over 90 %) and COD removal (approximately 88 %), increased sludge yield and organic matter content, and a 1.68-fold increase in energy recovery efficiency by sludge anaerobic digestion. The inhibition of nitrification relieved competition for carbon sources between denitrification and phosphorus removal, allowing for the enrichment of phosphorus-accumulating organisms (PAOs) such as Tetrasphaera and Halomonas, leading to enhanced phosphorus removal activities. Biological adsorption also plays a significant role in achieving steady phosphorus removal performance. This study demonstrates the potential of the S-SRT approach as an effective strategy for simultaneous carbon and phosphorus capture in the A-stage, contributing to energy and nutrient recovery from sewage.

Obtaining Phenolic-Enriched Liquid Fractions and Compostable Pomace for Agriculture from Alperujo Using Standard Two-Phase Olive Oil Mill Equipment

Olive oil extraction by two-phase systems generates a by-product called “alperujo” which presents several difficulties for its valorization. The present work evaluated an industrial approach, based on the application of thermal treatments to alperujo followed by solid/liquid separation using standard two-phase olive oil mill equipment. Treatments consisted of the thermo-malaxation of alperujo at 70 °C for 45 or 90 min, with or without acid addition, followed by solid/liquid separation in an industrial decanter. The solid was characterized concerning subsequent use for composting, while total and hydrophilic phenolics were analyzed in liquid for their recovery. Additionally, a laboratory-scale trial to compare phenolic purification by ethylic acetate extraction with chromatographic procedures was also included. The static respiration index showed that solid fractions presented higher susceptibility to biodegradation processes than raw alperujo. The phenolic content of treated liquid fractions was higher than in raw alperujo. Total phenolics were maximum at the longest exposure time without acid addition, while hydrophilic phenolics were highest at the shortest exposure time in acidified samples. The use of non-ionic resins seemed attractive for obtaining highly concentrated phenolic fractions. The proposed thermal treatments can be applied in olive oil industries, allowing in situ pomace valorization and the recovery of phenolic-enriched liquid fractions.