29 research outputs found

    天然から新規に単離したPestalotiopsis属菌による石油炭化水素の微生物分解

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    甲農博第878号Ehime University (愛媛大学)Doctral(includes post-doctral)博士(学術

    Biodecolorization of Remazol Brilliant Blue–R dye by Tropical White-Rot Fungi and Their Enzymes in The Presence of Guaiacol

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    The ability of the tropical white-rot fungi and their enzyme to decolorize synthetic dyes was investigated. Production of lignin-modifying enzymes (LMEs) from the three new isolated fungi, namely Trametes hirsuta D7, Ceriporia sp. BIOM 3, and Cymatoderma dendriticum WM01 were observed for 9 days incubation under static condition. The results showed that the LMEs production enhanced in the present of guaiacol. T. hirsuta D7 produced only laccase (Lac), with the highest activity was 22.6 U/L on the 5th-day of the cultivation. At the same time, Ceriporia sp. BIOM 3 and C. dendriticum WM01 secreted both laccases (Lac) with the activities 0.2 U/L and 1.0 U/L, respectively, and manganese peroxidase (MnP) with the activities 0.1 U/L and 1.0 U/L, respectively. Among the fungi, T. hirsuta D7 efficiently degraded 65% Remazol Brilliant Blue–R (RBBR) dye within 72 h using the only laccase. This study shows that laccase may have a major role in synthetic dyes' decolorization process, followed by MnP and LiP

    Potensi Cendawan Pelapuk Putih Indonesia Sebagai Agen Biodekolorisasi Limbah Pewarna Sintetik: Artikel Ulasan

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    oai:ojs.jmi.mikoina.or.id:article/75Limbah pewarna sintetik yang dihasilkan oleh industri tekstil dapat membahayakan ekosistem perairan dan organismenya pada konsentrasi tertentu. Proses dekolorisasi secara biologis menjadi fokus penelitian dalam beberapa tahun terakhir karena prosesnya yang relatif murah dan ramah lingkungan. Cendawan pelapuk putih merupakan salah satu mikroorganisme yang dimanfaatkan untuk memproses limbah pewarna melalui proses enzimatik maupun adsorpsi. Fokus dari review ini adalah untuk membahas cendawan pelapuk putih asal indonesia yang berpotensi sebagai agen biodekolorisasi limbah pewarna industri tekstil. Beberapa spesies cendawan pelapuk putih asal indonesia dari genus Ganoderma, Trametes, Pleurotus, dan Leiotrametes telah dilaporkan memiliki kemampuan mendekolorisasi beberapa jenis pewarna sintetik golongan antrakuinon dan azo. Faktor-faktor seperti jenis cendawan, pH, mediator, aktivitas dan jenis enzim, konsentrasi dan jenis pewarna yang diujikan, waktu inkubasi, dan teknik imobilisasi miselia atau ekstrak enzim ligninolitik berpengaruh terhadap proses dekolorisasi secara biologis

    The First Evidence of Potential Antibacterial Activity of Laccase Enzyme from Indonesian White Rot Fungi against Pathogenic Bacteria

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    The antibacterial agent can be extracted from plants, animals, and microorganisms such as fungi. The potential antibacterial activity of laccase derived from fungi remains limited in current reports. This study aimed to investigate the characteristics of laccase from Indonesian white rot fungi (WRF) and explore its potential as an antibacterial agent. The laccases were produced by Trametes hirsuta D7, Trametes hirsuta EDN 082, Leiotrametes menziesii BRB 73, and Lentinus sajor-caju BRB 12 using oil palm empty fruit bunch as a substrate. The results showed that the Indonesian WRF tested produced brownish-yellow laccase. FTIR analysis demonstrated similar peak patterns but distinct absorption intensities among the laccases. Trametes hirsuta D7 gained 0.044 U/ml of the greatest laccase activity. Laccase, with minimal activity of 0.001 U/ml–0.026 U/ml, suppressed the propagation of Propionibacterium acnes and Staphylococcus aureus. Escherichia coli and Pseudomonas aeruginosa could be inhibited by the laccase with a minimum activity of 0.002 U/ml–0.044 U/ml. However, S. aureus and E. coli showed the Minimum Bactericidal Concentration in the laccase activity range of 0.018 U/ml–0.308 U/ml. Gram-positive and Gram-negative bacteria grow more slowly when the laccase is present, supposed the laccase as a potential antibacterial agent

    Penerapan Teknik Elektrokoagulasi dalam Pengurangan Bahan Organik Air Limbah Kegiatan Perikanan

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    Electrocoagulation is one of physical techniques in waste-water treatment that applicable for organic waste from aquaculture. This research aims to determining the effectivity of electro-coagulation technique with different electrical voltages and duration consumed in waste-water treatment. The treatments used two electrical voltage levels (6 dan 12V) and four different durations of time consumed (15, 30, 45, and 60 minutes). The result showed the changes of water quality. Decreasing values shown by Chemical Oxygen Demand (COD) at the voltage of 12V and duration of 60’ (in about 82,89%); orthophosphate at the voltage of 12V and duration of 45’ (67.49%); turbidity at the voltage of 12V and duration of 60’ (69.65%); color at the voltage of 12V and duration of 60’ (70.49%); Total Suspended Solid (TSS) at the voltage of 12V and duration of 15’ (31.90%); and Total Dissolved Solid (TDS) at the voltafe of 12V and duration of 60’ (10.31%). Furthermore, increasing values were found in parameters of free ammonia at the voltage of 12V and duration of 15’ (291.09%); ammonium at the viltyage of 12V and duration of 30’ (8.85%); and pH at the voltage of 6V and duration of 60’ (16%). The best treatment in improving water quality of treated organic waste from aquaculture was the voltage of 12V for 30 minutes. Keywords: electro-coagulation, organic materials, water quality, waste-water treatmen

    Decolorization of Synthetic Dyes by Tropical Fungi Isolated from Taman Eden 100, Toba Samosir, North Sumatra, Indonesia

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    Taman Eden 100 is one of the tourist parks located in Toba Samosir, North Sumatra, Indonesia that provides a wide range of biodiversity. The objective of this research was to obtain the potential fungal isolate with high laccase activity to decolorize synthetic dyes. The results show that six isolates of Perenniporia subtephropora EDN 050, Trametes hirsuta EDN 082, T. hirsuta EDN 084, T. hirsuta EDN 085, Deconica coprophila EDN 114, and T. pavonia EDN 134, which were confirmed by molecular identification using 5.8 rDNA/ITS analysis, exhibited decolorization activity. Six potential isolates showed the ability to decolorize textile dyes of Acid Blue 129, RBBR,Orange II, and Reactive Black 5. The highest decolorization rate of 100 ppm Acid Blue 129, RBBR, Orange II, and Reactive Black 5 dyes by using T. pavonia EDN 134 were 98.87%, 98.26%, 100%, and 98.11%, respectively after 96 h incubation. Almost all positive isolates also decolorized dyes at higher concentrations (1,000 ppm). This study offers the potential of Indonesian tropical fungal isolates for synthetic dyes waste treatment

    Quantum-Sized Chitosan Modified ZnO for the Photocatalytic Oxidation of Oxytetracycline Under Fluorescent Light Irradiation

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    This study explores the ability of chitosan to control the size of ZnO quantum dots (CHT/ZnO QDs) and defects formation via the microwave-assisted method, as well as their photocatalytic oxidation activity towards oxytetracycline (OTC). The intramolecular and intermolecular hydrogen bonds within the chitosan -OH and -NH2 were altered by ZnO and microwave radiation. As a result, the particle size decreased from 9.35 ± 0.21 nm to 7.86 ± 0.28 nm. Additionally, the presence of chitosan led to higher oxygen vacancies ( Vs o) and Zni interstitials. The small size enhanced the absorption of photons, while defects suppressed the recombination rate of photogenerated electron/hole (e−/h+) pairs. The synthesized CHT/ZnO QDs exhibit outstanding photocatalytic performance by removing 97.4% of OTC within 40 min through pseudo-first-order kinetics with the rate constant (k) of 0.0568 min− 1 and driven by the h+ and O⋅−2 . This result was achieved by comprehensively investigating the impact of pH condition, initial concentration of OTC, and photocatalyst dosage. We believe that this work provides a potential photocatalyst design for antibiotics removal

    A review on the biological, physical and chemical mitigation of harmful algal bloom

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    The harmful algal bloom (HABs) refers to the rapid growth of toxic or high- biomass-producing microalgae. The impact of this phenomenon can cause significant economic loss affecting many industries and causing harm to wildlife and human health. As technology develops, greater research has been conducted to monitor and reduce HABs occurrence’s impact, including mitigating agents. This review presents the advantages and disadvantages of currently used and recently developed biological, chemical, and physical approaches to tackle issues related to HABs. The present review also emphasizes the interaction between the mitigating agents and the algal cells, thus identifying the gap of knowledge that needs to be addressed. Understanding the advantages and disadvantages of the approaches and the interaction between the mitigating agents and algal cells will enable researchers to develop a better sustainable system for managing HAB

    Insight into the photodegradation mechanism of bisphenol-A by oxygen doped mesoporous carbon nitride under visible light irradiation and DFT calculations

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    Oxygen doped mesoporous carbon nitride (O-MCN) was successfully synthesized through one-step thermal polymerization of urea and glucose utilizing nanodisc silica (NDS) from rice husk ash as a hard template. The CO2 gas, NH 3 and water vapor produced during the thermal process reshaped the morphology and textural properties of the of O-MCN compared to pristine mesoporous carbon nitride (MCN). Highest bisphenol A (BPA) removal achieved under visible light irradiation was 97%, with 60% mineralization ([BPA] ¼ 10 mg L�1 : catalyst dosage ¼ 40 mg L-1 ; pH ¼ 10; 180 min). In addition to mesoporosity, the sub-gap impurity states created from the oxygen doping reduced recombination rate of photogenerated carriers. Holes (h+ ) and superoxide (O2c�) were identified as the predominant active species responsible for the photodegradation process. The photodegradation route was proposed based on the intermediates detected by LC-time-of-flight/mass spectrometry (LC/TOF-MS). The Density of States (DOS) showed that oxygen doping resulted in a higher photoactivity due to the stronger localization and delocalization of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO). The adsorption pathway of the BPA on the O-MCN and MCN was successfully predicted using the DFT calculations, namely molecular electrostatic potential (MEP), global and local descriptors

    Highly porous bi(III) modified rice husk silica photocatalyst for the photocatalytic removal of cationic methylene blue

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    A series of bismuth-silicate photocatalysts were synthesized via the sol-gel method for photodegradation of methylene blue (MB) under sunlight irradiation, utilizing rice husk ash as a silica precursor. The scanning electron microscopy/energy dispersive X-ray (SEM/EDX) analysis detected Bi content in 3-10 wt% range. Furthermore, it can be seen that the porosity decreased as the Bi concentration increased. The N2 adsorption-desorption analysis indicates the presence of mesopores with an average diameter of 297-554 Å with Brunauer–Emmett–Teller (BET) surface area of 5.6-30.5 m2/g. The photocatalyst with a Bi concentration of 4 wt% (RHSBi-A2) was the most active in the photodegradation of MB; the removal reached 90% within 4 h. The photodegradation is proposed to be driven by superoxide (O2⦁−), hydroxyl (•OH) radicals, and hole (h+) based on the valence band (VB) and conduction band (CB) potentials. The porous silica framework is proposed to act as an electron reservoir, allowing better MB adsorption and enhancing light absorption
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