157 research outputs found
Tunichrome mimetic matrix, its perspective in abatement for carcinogenic hexavalent chromium and specific coordination behavior
No full textInspired by naturally occurring metal chelation strategy by pyrogallol moiety of tunichromes of marine tunicates, a strong retention of carcinogenic chromium (Cr-VI) is described by mimicking tunichrome matrix as a proof-of-concept investigation in water treatment applications. Harvesting tunichromes tailored with the pyrogallol moiety are extremely difficult owing to aerial sensitivity and purification difficulties, thus proving a challenging synthesis problem. Despite significant interest, knowledge of specific metal coordination in tunicate's matrix is still ambiguous, hindering study scope. We planned to fabricate a promising tunichrome matrix (TM) tailored with pyrogallol moieties from the Earth-abundant raw materials (gallic acid and chitin nanofiber) at mass scale without artificial aid. Specifically, we aimed at atomistic understanding of contaminant and pyrogallol moiety of TM by examining the structural parameters (redox change, geometrical distortion, coordination bond). Cr K-edge extended X-ray absorption fine structure (EXAFS) corresponds well to nontoxic Cr-III (average four Cr-O bond lengths of 1.91 angstrom) and a small fraction of Cr-VI (average two Cr-O bond lengths of 1.62 angstrom). A coupled reductive complexation mechanism was identified by combining near edge X-ray absorption fine structure (NEXAFS) and linear combination fits. From the viewpoint of practical utility and effective performance (nearly 119 mg chromium per g weight of TM), the impacts of water chemistry conditions were investigated from a variety of contaminated waters, showing a distinct improvement compared to conventional popular materials. The gained knowledge would be beneficial for utilizing a pyrogallol moiety as an alternative greener and sustainable scavenger, specifically for toxic chromium. (C) 2017 Elsevier B.V. All rights reserved.112sciescopu
Tunichrome-Inspired Gold-Enrichment Dispersion Matrix and Its Application in Water Treatment: A Proof-of-Concept Investigation
No full textTunicate, a filter-feeder in seawater, is able to accumulate high amount of metals using intracellular polymer matrices. The woven pyrogallol structures of tunichrome, a small peptide contained in tunicate's blood;Cells, is believed to, be responsible for selective. metal sequestration in tunicates from seawater. However, the intriguing tunichrome matrix is difficult both to harvest from the tunicate and to synthesize massively due to the-extreme oxidation sensitivity of the pyrogallol, moiety which limits the study scope. Here, we succeeded to mimic tunichrome by conjugating two cheap and naturally occurring components: pyrogallol-5-carboxylic acid (gallic acid) and chitin. nanofiber A tunicate-mimetic infiltration matrix of surface-tailored chitin nanofibers with pyrogallol moieties (CGa) demonstrated the versatility of this strategy in generation of ingenious filtration material, especially for unprecedented fine and-Clean gold recovery inside of the tunicate-mimetic infiltration matrix (>99%, 533 mg gold per gram weight), which exceeds that of the,presently most popular materials. Complexation between pyrogallol on the nanofiber and gold-was similar to that of a tunichrome's metal sequestration. Extended X-ray absorption fine Structure, (EXAFS); spectroscopy and data-fitting, elucidated the decreased coordination numbers for Au-Au nearest neighbors, demonstrating that gold coordinated to pyrogallol units, followed by an intramolecular association of Au-0. A catalytic reduction of 4-nitrophenol mediated by the-tunicate-mimetic matrix with harvested gold revealed excellent recyclability up to 30 cycles (similar to 95% reduction), which together with methylene-blue reduction and antimicrobial performances indicates the versatile characteristics,of sustainable processes by the tunichrome mimetics. This strategy opens the door for fast-developing new biomimetic alternatives for precious metal recovery, which is not restricted to gold and can offer a tool for multifaceted soft/hard nanomaterials..112sciescopu
Tunicate-Inspired Gallic Acid-Conjugated Chitin Nanofibrous Matrix for Metal Sequestration and Water Treatment Applications
No full textMasterTunicate, marine filter feeder, exhibit an outstanding metal sequestration ability on their blood cells through a series of complexation reaction with oligopeptide containing 3,4,5-trihydroxyphenilalanin (TOPA) moieties called tunichrome. Inspired by this naturally occurred strategy, we design a nano-bio filtration matrix mimicking tunichrome using two cheap and abundant precursor; pyrogallol-5-carboxylic acid (gallic acid) and chitin nanofiber, which is the chitin nanofibrous matrix tailored with gallic acids (CGa). The tunicate mimetic matrix (CGa) demonstrated the versatility of strategy in the generation of water filtration material, especially for 1) gold recovery and 2) carcinogenic hexavalent chromium removal. CGA showed unprecedented fine and clean gold recovery (>99%, 533 mg gold per gram weight), which exceeds that of the present most popular materials. Extended X-ray absorption fine structure (EXAFS) spectroscopy and data-fitting elucidated the decreased coordination numbers for Au-Au nearest neighbors, demonstrating gold coordinated to pyrogallol units, followed by an intramolecular association of Au0. A catalytic reduction of 4-nitrophenol mediated by the CGa with harvested gold revealed an excellent recyclability up to 30 cycles (~95% reduction), together with methylene blue reduction and antimicrobial performances, indicating a versatile characteristic of sustainable processes by the CGa.
In addition, the CGa also exhibits a superior performance towards carcinogenic hexavalent chromium removal (nearly 119 mg chromium per g weight of CGa). Cr K-edge extended X-ray absorption fine structure (EXAFS) corresponds well to nontoxic CrIII (average four Cr-O bond lengths of 1.91 Å) and a small fraction of CrVI (average two Cr-O bond lengths of 1.62 Å). A coupled reductive complexation mechanism was identified by combining near edge X-ray absorption fine structure (NEXAFS) and linear combination fits. This strategy opens the door for fast-developing new biomimetic alternatives for metal sequestration which is not restricted to gold and chromium and can offer a tool for multifaceted soft/hard nanomaterials
Fermentation Microbials Isolated from Marine: A Review
No full textMarine fish is one of the foodstuffs that containsk many compounds that are good for the human body. Marine fish contain omega-3 essential fatty acids as Docosahexanoic Acids (DHA) which are few other animal protein ingredients. This fish is rich in nutrients and minerals that can help prevent and maintain the body's immune system so that the body is fit. The benefits obtained include maintaining the cardiovascular system, efficient brain function, preventing damage to the thyroid gland and improving eye health. Fermentation is one way to process fishery products by utilizing the decomposition process of compounds from complex protein ingredients. To ferment food, microorganisms are needed that play a role in the decomposition of organic components in the material. Microorganisms commonly used are lactic acid bacteria (LAB), acetic acid bacteria (BAA), bacilli or other bacteria, yeast, or filamentous fungi.</jats:p
Rechtsvacuum in the Capital Market Regulation in Indonesia, A Case: The Embezzlement of Customers Funds by PT. Sarijaya Permana Sekuritas.Tbk.
No full textThe activities in the capital market have given an important influence on economic conditions in Indonesia. The capital market is one of the rapidly growing business areas. This resulted in the various crimes in the capital market which come up with diverse strategies. This happened in the case of embezzlement committed by the company in Indonesia. One of which is the embezzlement committed by directors and commissioners of Sarijaya Permana Sekuritas Company. The offense is not spesific regulated in The Act Number. 8 of 1995 about the Capital Market. This condition causes the confusion in the settlement of the case, that there is a rechtsvacuum. The author wants to analyse about how is the juridical analysis of rechtsvacuum in the embezzlement case of customers funds by Sarijaya Permana Sekuritas Company, and how is the law that should be used in the settlement of the case. This research is conducted with the study of documentation, namely collecting and researching of legal materials through a search of legal literatures by analyzing a legal decision from the court about the crime in the capital market, based on the Act and the related rules. In addition, the authors conclude that there is a rechtsvacuum in the case. In the consideration of the judgement, the judges stated that the defendant is proved guilty based on the judgement of the criminal case, but this case is a specific offence in the capital market and should be applied the Act of Capital Market. In Fact, In the Act of Capital Market has not the article about the embezzlement, with the result that in this case should be used the Criminal Code. Depending on these conditions, the regulations of capital market need to be revisited because there are some offenses are unregulated. Furthermore, the supervision by authority is important and needs to be tightened.
MEKANISME TOKSISITAS DAN DETOKSIFIKASI MIKROPLASTIK PADA MIKROALGA: LITERATURE REVIEW
No full textPartikel mikroplastik memiliki kemungkinan yang besar untuk berinteraksi dengan komunitas mikroalga, kelompok produsen primer utama di perairan, dan kemudian mengganggu keseimbangan ekologi serta memberikan resiko pada kesehatan manusia melalui mekanisme biomagnifikasi dan bioakumulasi. Tulisan ini bertujuan untuk mengkaji dampak fisiologi dari paparan mikroplastik pada mikroalga secara komprehensif serta mekanisme detoksifikasinya melalui studi yang telah dipublikasi. Studi literatur dilakukan dengan menelusuri artikel ilmiah pada basis data terindeks baik nasional maupun internasional. Artikel yang disertakan merupakan publikasi yang terbit maksimal 10 tahun terakhir (2014–2024) dan melaporkan data eksperimental mengenai paparan mikroplastik pada mikroalga air tawar maupun laut. Hasil studi literature dari penelitian – penelitian terdahulu yang terpublikasi di jurnal nasional dan internasional menunjukan bahwa secara fisiologi terlihat dari terhambatnya pertumbuhan sel, terganggunya proses fotosintesis, meningkatnya konsentrasi reactive oxygen species (ROS) beserta aktivitas anzim antioksidan yang terlibat dan peroksidasi membrane sel. Sel mikroalga dapat melakukan beberapa mekanisme dalam mempertahankan sel yaitu dengan sekresi polisakarida eksternal (EPS), pembentukan vakuola, homo-aggregasi dan hetero-aggregasi, serta detoksifikasi secara biokimia. Informasi mengenai dampak – dampak tersebut dibutuhkan sebagai upaya penanganan dan antisipasi pencemaran mikroplastik di perairan
Conservation Status of Marine Biota Sold in Restaurants in Pangandaran Regency, West Java
No full textOne of most potential activity regarding fisheries business in Pangandaran Regency is seafood restaurants which holds prospect for tourists. However, there are still many restaurants that sell conservationally-important biota. The purpose of this study is to identify the conservation status of marine biota sold in restaurants in Pangandaran Regency. Data was collected by observation or direct survey by purposive sampling in six seafood restaurants. The fish species were then identified for their conservation status based on the International Union for Conservation of Nature (IUCN) and the Convention on International Trade in Endangered Species (CITES). The identification results show that there were biotas included in the IUCN which were Lanjaman Shark (Carcharhinus sealei) with IUCN Appendix II CITES status, Black Fin Shark (Carcharhinus melanopterus) with IUCN Near Threatened (NT) status and Mobula Stingray (Mobula eregoodootenkee) with Endangered status. The results of this study indicated that conservation efforts need to be strengthened.
Phytoplankton Susceptibility Towards Toxic Heavy Metal Cadmium: Mechanism and Its Recent Updates
No full textEnvironmental pollution particularly heavy metal pollution into aquatic ecosystem has led to multiple damage in almost all life forms. Cadmium is one of the priority pollutant listed by United States Environmental Protection Agency or US EPA that widely known to have an adverse effect to organisms as well as human health. One type of organism that is susceptible to the effects of metal pollution is phytoplankton. Phytoplankton is a group of microalgae that are easy to find and are primary producers in aquatic environments. Phytoplankton plays an important role in aquatic ecosystems because they serve as primary producers. They are representing the water total primary productivity and reinforcing the aquatic life on the higher food chain. Thus, any threats that endangered the population of phytoplankton can lead to trophical cascade or even worse, biodiversity loss. The exposure of cadmium in high concentration to phytoplankton can lead to various impact including cell damage and disruption, biosynthesis inhibition of photosynthetic pigment (e.g. chlorophyll and carotenoid), chlorphyll degradation or known as chlorosis, thylakoid membrane degradation, inhibition of cellular metabolism and cell division. It is important to study the impact of cadmium to phytoplankton in a cellular level to better understand what mechanism lies and to what extent that the cadmium will be transferred to higher trophical organism via bioaccumulation or biomagnification
Kajian Analisis Kearifan Lokal Sebagai Landasan Konservasi Ikan Barau (Hampala macrolepidota)
No full textHampala barb (Hampala macrolepidota) is one of the commercial freshwater fish in Indonesia which is commonly caught in lakes and rivers in Sumatra. Due to the high market demand and habitat destruction, the new fish population is under pressure which affects its sustainability in nature. One of the efforts to preserve hampala barb is through the implementation of local wisdom in the form of the Mancokao tradition. This paper aims to examine the role of local wisdom in the conservation of hampala barb. Mancokao traditional activities as a form of local wisdom are one of the good management approaches because they involve the community in its implementation. Government support and its integration with the initiation of tourism areas can help sustain this tradition and at the same time as an effort to conserve this fish resourcesAbstrakIkan barau (Hampala macrolepidota) merupakan salah satu ikan air tawar komersial di Indonesia yang umum ditangkap di danau maupun sungai di daerah Sumatera. Permintaan pasar yang tinggi dan kerusakan habitat populasi ikan barau mengalami tekanan sehingga mempengaruhi kelestariannya di alam. Salah satu upaya pelestarian ikan barau di tempuh melalui pelaksanaan kearifan local berupa tradisi mancokao. Tulisan ini bersifat deskriptif dan bertujuan untuk mengkaji peranan kearifan lokal dalam konservasi ikan barau. Kegiatan tradisi mancokao sebagai bentuk kearifan local menjadi salah satu pendekataan pengelolaan yang baik karena melibatkan masyarakat dalam pelaksanaannya. Dukungan pemerintah dan integrasinya dengan inisiasi kawasam wisata dapat membantu keberlanjutan tradisi ini dan secara bersamaan sebagai upaya konservasi sumberdaya ikan barau
Status Konservasi Biota Laut yang Teridentifikasi di Tempat Pelelangan Ikan (TPI) Kabupaten Pangandaran, Jawa Barat
No full textKabupaten Pangandaran merupakan salah satu daerah dengan aktivitas perikanan tangkap yang potensial di Jawa Barat dengan pengoprasian umumnya di wilayah pengelolaan perikanan (WPP) 573. Luasnya daerah potensial penangkapan ini menyebabkan kemungkinan komoditas non-target menjadi lebih tinggi, termasuk biota laut dengan status konservasi tinggi. Penelitian ini bertujuan untuk mengidentifikasi dan mengkaji status konservasi komoditas perikanan yang dilelang di Tempat Pelelangan Ikan (TPI) yang terdapat di Kabupaten Pangandaran. Metode yang dilakukan dalam penyusunan ini ialah metode observasi dan deskriptif eksploratif yang dilakukan dengan mengidentifikasi sampel yang diperoleh di beberapa TPI Kabupaten Pangandaran diantaranya TPI Cikidang, TPI Minasari, TPI Pantai Timur, dan TPI Bojong Salawe. Hasil observasi dianalisis dengan menyocokan biota yang teridentifikasi dengan daftar merah pada International Union for Conservation Nature (IUCN). Berdasarkan hasil pengamatan diperoleh beberapa biota yang termasuk ke dalam kriteria Near Threatened, kepunahan dan Edangered. Dapat disimpulkan dari pengamatan yang telah dilakukan di lapangan yaitu terdapat 6 spesies yang dilindungi dan didaratkan di TPI Kabupaten Pangandaran dengan status konservasi Appendix II CITES, Near Threatened dan Endangered. Hal ini menunjukan bahwa upaya konservasi perlu diperkuat dengan memberikan pemahaman kepada nelayan yang ada di Kabupaten Pangandaran terkait status konservasi biota yang dilindungi dalam IUC
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