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Methods for removing pollutants include membrane isolation, ion exchange, precipitation, transformation, and biosorption. Adsorption is a cost-effective method of treating industrial wastewater and a common commercial method for concentrating valuable molecules or eliminating contaminants. Banana peel is one of the largest underutilized agricultural wastes in Malaysia. A novel method of using a low-cost biosorbent made from banana peel and Evans blue (EB) dye as a target is the target of this study. The optimal conditions for EB dye adsorption occurred at a dye concentration of 200 mg/L, adsorbent dosages between 10 and 20 g/L, temperature of 25 °C, incubation time of 180 min, and agitation speeds of 100 rpm. Statistical discriminatory analysis showed that the pseudo-second-order kinetic model and the Redlich–Petersen isotherm model were the best models. The maximum adsorption capacity based on Langmuir’s isotherm prediction was 58.51 mg g−1. A non–linear regression of the thermodynamic van’t Hoff plot based on a dimensionless equilibrium constant resulted in negative values for Gibb’s free energy and enthalpy, indicating that the adsorption process is spontaneous and exothermic.

The growing clamor about the climate crisis has brought into focus the need for action to drastically reduce CO2 emissions, particularly from the road transport sector. This systematic literature review examines the nexus between fossil fuel subsidies, fuel consumption, and CO2 emissions from the road transport sector. Despite numerous research contributions that provide the foundation on this topic, the body of research appears to be quite fragmented with regard to the stated nexus. This systematic literature review consolidates currently available research and provides the basis for further research on the connection between fuel subsidy, fuel consumption, and CO2 emissions. Keywords: Fossil Fuel Subsidy; Transport Emissions; Subsidy Reform; Systematic Literature Review eISSN: 2398-4287© 2021. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open access article under the CC BYNC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians/Africans/Arabians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia. DOI: https://doi.org/10.21834/ebpj.v6i16.2721

Microplastics contamination is becoming a major concern worldwide. More than 1 million seabirds and 100,000 sea animals have died due to plastic contamination. In addition, plastic particles have been found in juvenile turtles. Statistical data on plastic pollution indicate that this is a serious issue. Due to their small size, microplastics have a large surface area and have more ability to absorb into biological cells. The hydrophobic surface of microplastics attracts co-contaminants such as heavy metals, pharmaceutical toxicants, flame retardants, and other plasticizers, which can then enter biological organisms. Microplastics are usually recalcitrant in the environment, causing microplastics to be transported along the food chain, with humans as the final consumer. Research has been conducted to evaluate the best way to treat and remediate microplastic pollution. Research on microplastic degradation is focused on biological and non-biological approaches. To date, microorganisms such as algae, fungi, and bacteria have attracted the attention of scientists as a tool for microplastic treatment. The degradation of microplastics is closely related to the enzymatic reactions produced by the microorganisms. Here we review microplastics degradation through enzymes from the microorganism’s perspective. We present the enzymes that have been isolated from microorganisms for specific microplastics; the mechanisms of microplastics degradation by various enzymes; and the types of microplastics for which degradation mechanisms remain unclear.

Heavy metal wastes, particularly hexavalent chromium [Cr(VI)], are generated from anthropogenic activities, and their increasing abundance has been a research concern due to their toxicity, genotoxicity, carcinogenicity and mutagenicity. Exposure to these dangerous pollutants could lead to chronic infections and even mortality in humans and animals. Bioremediation using microorganisms, particularly bacteria, has gained considerable interest because it can remove contaminants naturally and is safe to the surrounding environment. Bacteria, such as Pseudomonas putida and Bacillus subtilis, can reduce the toxic Cr(VI) to the less toxic trivalent chromium Cr(III) through mechanisms including biotransformation, biosorption and bioaccumulation. These mechanisms are mostly linked to chromium reductase and nitroreductase enzymes, which are involved in the Cr(VI) reduction pathway. However, relevant data on the nitroreductase route remain insufficient. Thus, this work proposes an alternative metabolic pathway of nitroreductase, wherein nitrate activates the reaction and indirectly reduces toxic chromium. This nitroreductase pathway occurs concurrently with the chromium reduction pathway.

Effect of temperature on the adsorption process will be reflected in the thermodynamic parameters. These data provide information on the efficiency of the adsorption process. Thus, an appropriate calculation for the thermodynamic parameter is crucial in adsorption research. In this paper, thermodynamic parameter data from a previously published paper on glyphosate adsorption onto AC/Mn/Fe was re-evaluated using the newly proposed method based on dimensionless equilibrium constant (Kc) derived from Langmuir sorption method. The recalculated results are as follows; entropy, ΔS°=224.04 J mol-1, enthalpy, ΔH° =39.97 kJ mol-1 and the range of Gibs fee energy for the five investigated temperature (5 ⁰C, 15 ⁰C, 25 ⁰C, 35 ⁰C and 45 ⁰C) were ΔG°278.15K = -22.26 kJ mol-1 and ΔG°318.15K = -32.52 kJ mol-1. Recalculated value of thermodynamics presented in this paper is mostly beyond the original data. Significant differences were observed in the sign and magnitude of ΔS° and the value of ΔG° of the tested temperature. Interestingly, the actual experiment was well represented by the recalculated results. Here we suggested the alternative calculation for thermodynamic parameters using the dimensionless equilibrium constant Kc.

Pollutant treatment methods are available for membrane isolation, exchange of ions, precipitation, transformation and biosorption. Biosorption has many positive aspects of all this technology, including low running costs, very effective toxicant detoxification at low concentrations, low levels of disposal materials. In many applications, adsorption plays an important role in concentrating useful compounds or eliminating contaminants. The thermodynamic parameters of the adsorption are often obtained from the relation between the adsorption constant (KC in Lmol-1 unit) and the Gibbs free adsorption energy. When the van’t Hoff plot for the temperature range 298.2 K to 328.2 K was plotted, a nonlinear curve was obtained with poor R2 value (R=0.491). In order to calculate the ΔH° and ΔS° more accurately, the thermodynamics parameters were analysed at two processes: one between 298.2 and 301.2 K and another at between 301.2 and 328.2 K which gave a better R2 values of 1.00 and 0.995, respectively. The ∆G°, ∆H° (kJ/mol) and ∆S° (kJ/mol×K) values for temperatures between 298.2 and 301.2 K and between 301.2 and 328.2 K were –29.4524, 14.65, 0.145 and –30.4787, –14.88 and 0.049, respectively. This paper depicts with the proposed workflow in the analysis of liquid-phase adsorption data from the data acquisition to data analysis and thermodynamics appropriate calculation of the dimensionless KC parameter.

Pendahuluan: Apendisitis akut merupakan salah satu penyebab operasi gawat darurat dalam bidang gastroenterohepatologi. Hanya apendisitis yang terkomplikasi seperti perforasi yang memerlukan tindakan operasi. Saat ini belum ditemukan cara untuk menegakkan apakah pasien apendisitis yang datang perlu dilakukan operasi atau hanya dengan terapi konservatif dengan antibiotik. Salah satu pemeriksaan yang dapat dikaitkan pada apendisitis adalah Matriks Metalloproteinase (MMP). Tinjauan pustaka ini bertujuan untuk mengetahui potensi dan sensitivitas MMP sebagai biomarker untuk menentukan kemungkinan terjadinya perforasi pada apendisitis akut. Metode: Artikel dibuat dengan metode literature review dengan menggunakan textbook dan 21 jurnal, dengan 10 jurnal utama. Jurnal diperoleh dari search engine Pubmed, Cochrane, dan Google Scholar. Pembahasan: MMP memiliki sifat proteolitik terhadap matriks ekstraseluler pada jaringan ikat yang meningkat pada reaksi inflamasi. Ketidakseimbangan MMP terhadap Tissue Inhibitor of Metalloproteinase (TIMP) pada apendisitis menyebabkan peningkatan aktvitias proteolisis yang merusak dinding apendiks yang menjadi patofisiologi perforasi. Ekspresi dan konsentrasi MMP dijumpai meningkat secara signifikan pada pemeriksaan biopsi, imunohistokimia, cairan peritoneum, dan serum pasien yang mengalami komplikasi apendisitis dibandingkan dengan apendisitis tanpa komplikasi. MMP mampu membedakan apendisitis terkomplikasi dengan tidak, namun membutuhkan pemeriksaan TIMP untuk menentukan jenis komplikasi apendisitis. Simpulan: Pemeriksaan MMP dan TIMP berpotensi menjadi biomarker terjadinya perforasi pada apendisitis. Saran: Diperlukan penelitian lebih lanjut untuk menentukan nilai cut-off pada apendisitis.

Application of dyes is prevalent in industries involved in textile and food manufacturing. Effluent discharge from these industries to neighbouring water bodies cause significant health concerns due to dye toxicity. To date, only very few bacteria are isolated with the ability to completely assimilate dyes. The main objective of this study is to isolate bacteria(s) with the ability to utilise reactive red dye 120. Local strains were isolated from contaminated sites in Northern Malaysia. Based on 16S rDNA gene sequence analysis, the best strain was identified as Pseudomonas sp. strain DRY011. Optimum RR120 decolourisation was observed at 200 ppm with 71.07% removal rate within 5 days and able to tolerate up to 500 ppm. The effect of heavy metals (silver, arsenic, cadmium, chromium, copper, mercury, lead and zinc) were investigated. Mercury, 1 ppm had the highest inhibition effect, followed by zinc and silver, with decolourisation of 12 % and 14.3 % respectively. Chromium had the least effect with 55.6% decolourisation and bacterial growth of 11.5 CFU/mL. The rest of the heavy metal had the least effect on the decolourisation rate. As a conclusion, the finding of microbial degrader able to utilise dye will become crucial bioremediation key in controlling the level of dye wastes in water bodies.

Established approaches for the management of contaminants include things like membrane separation, ion exchange, precipitation, transformation and biosorption. Of all of these technologies, biosorption has lots of features that include low running expenditures, very effective detoxification of toxicants at low levels, low quantity of removal components as well as does not require nutrient needs as with bacterial-based remediation, theaforementioned being restricted to the existence of heavy metals and other toxicants. The biosorption of BDE-3 on spent black tea was successfully fitted to three models—pseudo-1st, pseudo-2nd and Elovich. Statistical analysis based on root-mean-square error (RMSE), adjusted coefficient of determination (adjR2), accuracy factor (AF), bias factor (BF), corrected AICc Bayesian Information Criterion (BIC), (Akaike Information Criterion) and Hannan–Quinn information criterion (HQC) showed that the pseudo-second order model is the best model giving valuable parameters such as the equilibrium sorption capacity qe and the pseudo-second-order rate constant, k2, which can be further utilized in isothermal modelling analysis. Further analysis is needed to provide proof for the chemisorption mechanism usually tied to this kinetic.

A bacterium capable of degrading sodium dodecyl sulphate (SDS) is characterized. Previously, the bacterium has been shown to have the capability to reduce molybdenum to molybdenum blue. In this report, we showed that almost complete degradation of SDS was observed in 6 to 10 days when the bacterium was grown on medium supplemented with SDS ranging from 0.5 to 1 g L-1 while higher concentrations showed partial degradation with no degradation was observed at concentrations higher than 2.5 g L-1. Other detergents were also tested including Tergitol NP9, Tergitol 15S9, Witconol 2301 (methyl oleate), sodium dodecylbenzene sulfonate (SDBS), benzethonium chloride and benzalkonium chloride. However, growth can only be seen on the anionic SDBS. We also showed that the presence of metal ions such as silver, copper, cadmium, chromium, lead and mercury inhibits the ability of the bacterium to degrade SDS by 50%. Growth on SDS could not support molybdenum-reduction in this bacterium. Growth kinetic studies showed that the growth rate could be modelled using Haldane substrate inhibition kinetics with the maximum growth rate, µmax, was 0.13 h-1, while the saturation constant or half velocity constant Ks and inhibition constant Ki, were 0.707 and 11.303 g L-1 SDS, respectively.

The yeast Rhodotorula sp. Strain MBH23 (KCTC 11960BP) is an efficient acrylamide-degrader and is able to tolerate high concentrations of acrylamide. A primary modelling exercise for the growth of this yeast on acrylamide yields important specific growth rates which were utilized successfully for secondary modelling exercise which gave Luong as the best model. The Luong’s constants; maximal growth rate, half-saturation constant for maximal growth, maximal concentration of substrate tolerated and curve parameter that defines the steepness of the growth rate decline from the maximum rate symbolized by max, Ks, Sm, and n (± standard error) were 0.099±0.017 hr-1, 17.34 ± 5.0 mg/L, 2053.0 ±56.0 mg/L and 0.801±0.202, respectively. The Luong model indicates that acrylamide is toxic and inhibits the growth of this yeast. To date, this is the first time that such a modelling exercise was utilized to model growth kinetics on acrylamide.

This present research work was conducted to determine the phytotoxic effects on tropical native plants, Ludwigia octovalvis, in order to assess its application for phytoremediation of crude oil sludge in contaminated sand. For this purpose of study, L. octavalvis plants were planted in containers containing different proportion of spiked real crude oil sludge in sand (10%, 50%, and 100% (v/v)). Degradation of crude oil sludge by L. octovalvis was measured in terms of total petroleum hydrocarbons (TPH) and was compared with TPH degradation inside control crates without plants. The findings indicated that the average TPH removal after a prolonged 42-day exposure period was high. The degrees of TPH degradation were 67.0, 42.4 and 46.2% in sand spiked with real crude oil sludge at 10, 50 and 100% respectively, whereas the degradation was only 34.7, 29.1 and 20.5% for the unplanted containers at the same respective proportions of crude oil sludge in sand. These findings give evidence that L. octovalvis has the capability to degrade hydrocarbons in crude oil sludge.

Jatropha curcas is a medicinal plant with many therapeutic properties such as anti-inflammatory, anti-malaria, anti-cancer and antioxidant. The root extract has been shown to possess high anti-inflammatory activity. Previously, the compounds responsible for this activity have not been fully elucidated. Two fractions (Fraction 1 and Fraction 2) obtained from a preparative HPLC of the root extract showed significant anti-inflammatory and cytotoxic activities in RAW 264.7 murine macrophage cells with Fraction 1 giving higher nitric oxide (NO) inhibition compared to Fraction 2 and L-NAME. Further purification steps involving column chromatography, thin layer chromatography and analytical HPLC of Fraction 1 produced two fractions labeled as Fraction A and Fraction B. Both fractions showed anti-inflammatory activity without cytotoxic activity in RAW 264.7 cells. Liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis showed that Fraction A contained a group of 18 carbon fatty acid compounds consisting of 2 oxooctadecanoic acids; 15, 16 dihydroxy 9Z, 12Z octadecadienoic acid; octadecadienoic isomer and 15,16 dihydroxy 9Z, 12Z octadecadienoic acid, 15S, 16S. The 18-carbon fatty acid structure was confirmed by nuclear magnetic resonance (NMR) spectral data. The IC50 value of compounds in Fraction A for anti-inflammatory activity in RAW 264.7 cell line was 434.8±0.75 µg/mL. From the analysis, it can be concluded that Fraction A can be classified under 18 carbon long chain fatty acid group based on LC MS/MS and NMR analysis. This active compound shows an inhibition towards NO activity.

Using a systematic literature review, we explore fuel subsidies and consumer environmental awareness among users in urban road transport. Fuel subsidies given by the government to the public have to some extent brought them to more using own transport as the fuel cost is now cheaper. A growing number of vehicles and usage in the urban road transport sector worldwide has increased CO2 emissions and impact on environment. The misalignment of benefits from the implementation of fossil fuel subsidies and high emissions has grown attention to limit global warming since the Paris Agreement 2015 was signed. Nonetheless, consumer environmental awareness is interesting to bring forward for future research. Keywords: Fuel Subsidy, Consumer Environmental Awareness, Urban Road Transport, Systematic Literature Review eISSN: 2398-4287© 2021. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open access article under the CC BYNC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians/Africans/Arabians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia. DOI: https://doi.org/10.21834/ebpj.v6i18.3097

Bioaugmentation, the addition of cultured microorganisms to enhance the currently existing microbial community, is an option to remediate contaminated areas. Several studies reported the success of the bioaugmentation method in treating heavy metal contaminated soil, but concerns related to the applicability of this method in real-scale application were raised. A comprehensive analysis of the mechanisms of heavy metal treatment by microbes (especially bacteria) and the concerns related to the possible application in the real scale were juxtaposed to show the weakness of the claim. This review proposes the use of bioaugmentation-assisted phytoremediation in treating heavy metal contaminated soil. The performance of bioaugmentation-assisted phytoremediation in treating heavy metal contaminated soil as well as the mechanisms of removal and interactions between plants and microbes are also discussed in detail. Bioaugmentation-assisted phytoremediation shows greater efficiencies and performs complete metal removal from soil compared with only bioaugmentation. Research related to selection of hyperaccumulator species, potential microbial species, analysis of interaction mechanisms, and potential usage of treating plant biomass after treatment are suggested as future research directions to enhance this currently proposed topic.

The application of plant-based coagulants in wastewater treatment has increasingly progressed in the coagulation–flocculation process toward green economy and cleaner production. Plant-based coagulants have a potential as essential substitutes for commercially used chemical coagulants because of their natural characteristics and biodegradability. Chemical coagulants leave residues in treated water and generated sludge, which cause harm to human health and the ecosystem. Thus, the exploration of plant-based coagulants in wastewater treatment could reduce and eliminate the potential damage of chemical coagulants and promote the alternative approach for sustainable environment. The general processing steps of the end-to-end plant-based coagulant production, which includes primary, secondary, and tertiary stages, are discussed. However, this review focuses more on the extraction process using different solutions and compares the performance of different coagulants in removal activities after effluent treatment. Discussion on the arising challenges is elaborated, and approaches for plant-based coagulant research in the near future are suggested.

Biocoagulants and bioflocculants are alternative items that can be used to substitute the utilization of common-chemical coagulants and flocculants. Biocoagulants/bioflocculants can be extracted from animals, microorganisms, and plants. Moreover, biocoagulants/bioflocculants have specific characteristics that contribute to the coagulation and flocculation processes. The active compounds inside biocoagulants/bioflocculants vary and correspond to the specific working mechanisms, including charge neutralization, sweep coagulation, adsorption, bridging, and patch flocculation. This review paper summarizes the characteristics of biocoagulants/bioflocculants from different sources and its performance in treating various pollutants. Furthermore, this paper discusses the most contributing compounds and functional groups of biocoagulants/bioflocculants that can be related to their working mechanisms. Several functional groups and compounds in biocoagulants/bioflocculants are highlighted in this review article, as well as the correlation between the highlighted groups/compounds to the aforementioned coagulation-flocculation mechanisms. In addition, current knowledge gaps in the study of biocoagulants/bioflocculants and future approaches that may serve as research directions are also emphasized. This review article is expected to shed information on the characteristics of biocoagulants/bioflocculants, which may then become a focus in the optimization to obtain higher performance in future application of coagulation-flocculation processes.

Bioflocculants gain attention as alternatives to chemical flocculants because they are more environmentally friendly and highly biodegradable. This study aims to improve the bioflocculant production by Serratia marcescens using one-variable-at-a-time (OVAT) analysis and analyze its flocculating activity performance, toxicity, and the flocculation mechanism. The effect of multiple variables including initial inoculum size, pH, mixing speed, temperature, growth medium, and incubation period was assessed through OVAT. Flocculating activity was then determined via jar test analysis, and toxicity test was performed using Daphnia magna and Daphnia pulex. The flocculation mechanism was determined via particle size distribution and zeta potential analysis. The optimum conditions for the improved bioflocculant production were as follows: 10% v/v initial inoculum size, pH 7, mixing speed of 150 rpm, room temperature, nutrient broth medium, and 72 h of incubation period. Scanning electron microscopy showed flake-like intact structure with coarse surface. The produced bioflocculant showed flocculating activity of 48% in 5227 ± 580 NTU initial kaolin turbidity with 1 mg/L concentration and 5% v/v dosage of bioflocculant, following the second-order kinetics. Toxicity test to D. magna and D. pulex showed the 48 h LC