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Palm oil mill effluent (POME) is the dark brown agricultural wastewater from palm oil extraction factories. It is difficult to decolorize using conventional methods. Melanoidin is a dark-colored polymer formed through the Maillard reaction which is the primary cause of the dark color in POME. This study investigated the potential of a photosynthetic bacterial consortium consisting of Blastochloris sulfoviridis and Lentimicrobium saccharophilum for POME treatment and bioenergy generation. The consortium effectively removed melanoidin content (68.89±0.84%) and color (60.87±1.22%) from POME without the addition of chemicals or culture medium. Additionally, a microbial fuel cell (MFC) integrated with the consortium generated apower output of up to 5.70±1.06 W m-3. The degraded metabolites were analyzed by gas chromatography-mass spectrometry (GC-MS) after treatment. The results revealed that melanoidin was converted to 1-ethyl-2-methylbenzene, 1,2,4-trimethylbenzene, decamethylcyclopentasiloxane, dodecamethylcyclohexane, butylated hydroxytoluene, and stigmasta-3,5-diene. Following treatment, the cell pellet was recovered and analyzed for valuable by-products. Carotenoid and astaxanthin pigments were extracted with yields of 0.32±0.01 and 0.02±0.00 mg g-1, respectively. These findings demonstrate the versatility of the photosynthetic bacterial consortium, which offers a sustainable solution for POME treatment while simultaneously POME decolorization and producing bioenergy and valuable compounds.

The increasing volume of wastewater from fish farming poses a serious environmental threat. This study investigated a novel treatment method for butter catfish (Ompok bimaculatus) wastewater using a constructed wetland-microbial fuel cell (CW-MFC) integrated with the water fern Azolla microphylla. The system was effectiveness in removing pollutants like electrical conductivity (EC), total dissolved solids (TDS), ammonium, nitrate, nitrite, and phosphate was evaluated. Additionally, the electricity generation capabilities were measured. The CW-MFC system achieved significant removal rates: 67.65% for EC, 61.67% for TDS, 100% for ammonium, 75.00% for nitrate, 81.25% for nitrite, and 70.00% for phosphate. Furthermore, the system generated a maximum open-circuit voltage (OCV) of 690±90 mV, a current density (CD) of 7.29±0.43 mA/m³and a power density (PD) of 0.37±0.04 mW/m³. Analysis of the microbial community revealed a diverse root consortium dominated by bacterial genera including Phreatobacter, Emticicia and Rhodobacter, along with fungal genera such as Strelitziana, Ramularia, Cladosporium,Trichomerium, Cercospora, Erythrobasidium and Fusarium. These findings suggest that CW-MFC systems integrated with A. microphylla offer a promising approach for sustainable and efficient treatment of wastewater from catfish farming while simultaneously generating bioelectricity.

This study investigated the application of a microbial fuel cell (MFC) system integrated with freshwater microalgae Chlorella sp. TSU-FF67for wastewater treatment, electricity generation, and bio-oil production. The MFC with Chlorella sp. TSU-FF67achieved a significantly higher open-circuit voltage (OCV) of 413.67 ± 15.67 mV compared to the control (13.33 ± 6.38 mV), indicating enhanced bioelectrocatalytic activity. The system also demonstrated efficient organic matter removal from palm oil mill effluent (POME) with a maximum color removal of 95.12 ± 3.50%. Furthermore, Chlorella sp. TSU-FF67 recovered from the PMFC exhibited a remarkable docosahexaenoic acid (DHA) yield of 1,932.28 ± 88.69 µg/mL (1.93 ± 0.08 mg/mL), highlighting its potential as a feedstock for bio-oil production. This work presents a promising approach for sustainable wastewater treatment while simultaneously generating bioelectricity and bio-oil using microalgae-MFC integration.

This study investigates the effect of microbial configuration on the electrochemical performance of photosynthetic microbial fuel cells (PMFCs). The PMFC configuration incorporating both bacteria and microalgae exhibited the highest open-circuit voltage (OCV) of 397.95 ± 31.53 mV, significantly higher than that of the OCVs obtained in the sterile control (C1) and the microalgae-only configuration (C2), which were 32.47 ± 22.43 mV and 284.59 ± 12.63 mV, respectively. Furthermore, the PMFC containing only microalgae achieved a current density (CD) of 20.96 ± 0.18 mA/m³ and a power density (PD) of 0.40 ± 0.01 mW/m³ under room temperature conditions. Notably, the combined bacteria and microalgae configuration demonstrated a substantial performance improvement, yielding a significantly higher CD of 49.33 ± 0.36 mA/m³ and PD of 0.78 ± 0.01 mW/m³ at room temperature. This configuration also achieved a maximum decolorization of 93.57 ± 0.10% with a corresponding algal biomass recovery of 134.90 ± 2.69 mg/L. These findings highlighted the critical role of microbial composition in PMFC performance. The combination of bacteria and microalgae yielded superior results compared to other configurations under the investigated conditions.

Aim of the study: In our investigation, we used freshwater microalgae Chlorella sp. BF01 to degrade the melanoidin in the palm oil mill effluent, and generate electricity in the photosynthetic microbial fuel cell (PMFC). Material and methods: The freshwater microalgae Chlorella sp. were used in a PMFC consortium for the degradation of melanoidin and electricity generation. The removal (%), electrochemical properties, and biomass recovery were monitored without adding an exogenous medium. Results and conclusions: In this study, lipid-producing microalgae were employed as whole-cell biocatalysts in a PMFC using palm oil mill effluent as a substrate. The maximum melanoidin removal of 79.54 ± 0.45% was gained. The maximum power density reached was 3.98 ± 0.10 W/m3. The paper presents research findings that pave the way for a practical implementation of this innovative approach on an industrial scale.

The persistence of the carcinogenic Rhodamine B dye poses significant risks to human health. Utilizing a unique fungal strain for its degradation offers a sustainable solution to mitigate these hazards. Bioremediation techniques have demonstrated substantial promise in addressing recalcitrant pollutants such as dyes. In this particular study, laccase-producing fungi were carefully chosen for their potential to break down the toxic textile dye Rhodamine B. These selected fungi Cerrena unicolor FBR03 exhibited an impressive maximum degradation rate of 95.10%. Additionally, an analysis using GC-MS revealed the emergence of breakdown products, including 2-cyclopenten-1-one, 3-hydroxy-2-methyl, thymine, dodecanoic acid, tetradecanoic acid, n-hexadecanoic acid, and dibutyl phthalate. These results underscore the potential of this fungal strain as a promising organism for the effective degradation of dye compounds, while simultaneously producing valuable saturated fatty acids as by-products.

The contamination of the environment by antibiotics has become a serious problem, supported by abundant scientific evidence of its negative impact on both aquatic ecosystems and human health. Therefore, it is crucial to intensify research efforts towards developing effective and efficient processes for removing antibiotics from the aquatic environment. In this study, a bacterial consortium capable of breaking down penicillin was employed in a ceramic separator microbial fuel cell (MFC) to generate electricity. The consortium’s properties such as laccase activity, penicillin removal and microbial structure were studied. The SF11 bacterial consortium, with a laccase activity of 6.16±0.04 U/mL, was found to be effective in breaking down penicillin. The highest rate of penicillin removal (92.15±0.27%) was achieved when the SF11 consortium was incubated at 30 °C for 48 hours. Furthermore, when used as a whole-cell biocatalyst in a low-cost upflow MFC, the Morganella morganii-rich SF11 consortium demonstrated the highest voltage and power density of 964.93±1.86 mV and 0.56±0.00 W/m3, respectively. These results suggest that the SF11 bacterial consortium has the potential for use in ceramic separator MFCs for the removal of penicillin and electricity generation.

Stingless bee honey is a nutritious food that contains a variety of vitamins, minerals, enzymes, and antioxidants. It is known to have higher nutritional and medicinal properties compared to honey produced by other bee species. Cider is a well-known functional drink that contains high antioxidants, which can help protect against cellular damage caused by free radicals. This study aimed to investigate the potential of co-fermentation with yeast (Saccharomyces cerevisiae) and bacterium (Lactobacillus sp.) in producing high-antioxidant honey cider when compare with standard antioxidant. The results showed that honey cider co-fermented with both microorganisms for 14 days had significantly higher antioxidant activity (145.27 ± 0.20 µg TE/mL) compared to single culture fermentation (p < 0.05). Gas chromatography-mass spectrometry (GC-MS) analysis revealed the presence of several bioactive compounds in the stingless bee honey cider. These compounds include methylenecyclopropanecarboxylic acid, 2(5H)-furanone, 2-methylbicyclo[4.3.0]non-1(6)-ene, bicyclo[3.1.0]hex-2-ene, 4-methyl-1-(1-methylethyl), D-limonene, benzene, 1-(1-butenyl)-4-methoxy, and phytol. These compounds possess various beneficial activities, such as antioxidant, anti-inflammatory, antimicrobial, and anticancer properties. The identification of these compounds in the stingless bee honey cider suggests that it may have potential health benefits beyond its nutritional value. The co-fermentation approach using S. cerevisiae and Lactobacillus sp. could be considered a promising strategy for developing antioxidant-enriched honey cider with potential health benefits.

Mead, an ancient alcoholic beverage, relies on the indigenous microbial community in honey for alcohol fermentation. Nevertheless, data on the use of bee indigenous flora for mead production in Thailand are scarce. This investigation involved the isolation of alcohol-producing yeast strains from the Thai stingless bee species Heterotrigona itama. Subsequently, these isolated yeast strains were employed in mead fermentation with honey sourced from the same stingless bee species. Findings revealed that the yeast strain denoted as P03b, which was identified molecularly as Saccharomyces cerevisiae, exhibited the highest alcohol production of 13.53% ± 0.76%. Furthermore, the yeast strain P03b demonstrated notable stress tolerance, including resistance to elevated osmotic pressure (30% w/v glucose), extreme pH conditions (pH 2), and high ethanol content (20% w/v). In mead fermentation, the highest observed alcohol concentration reached 10.20% ± 0.26%. The resultant mead had a pH of 3.54% ± 0.04% and total reducing sugar content of 0.04 ± 0.00 mg/mL. This study provides new knowledge on using indigenous yeast in Thai stingless bee combs for alcohol beverage production. [ABSTRACT FROM AUTHOR]