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Journal : HAYATI Journal of Biosciences

High utilization of fossil fuel increases the level of carbon dioxide in the atmosphere and results in global warming phenomenon. These things establish the world’s thought to look for the other alternative energy that can reduce the use of fossil fuel even to be replaced by the substitute. Recently, Indonesia has been doing the research of microalgae as a feedstock of an alternative biofuel. Fatty acid content that microalgae have is also high to produce biofuel. The steps used in this research TRI PRARTONO; MUJIZAT KAWAROE; DAHLIA WULAN SARI; DINA AUGUSTINE
HAYATI Journal of Biosciences Vol. 17 No. 4 (2010): December 2010
Publisher : Bogor Agricultural University, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.4308/hjb.17.4.196

Abstract

High utilization of fossil fuel increases the level of carbon dioxide in the atmosphere and results in global warming phenomenon. These things establish the world’s thought to look for the other alternative energy that can reduce the use of fossil fuel even to be replaced by the substitute. Recently, Indonesia has been doing the research of microalgae as a feedstock of an alternative biofuel. Fatty acid content that microalgae have is also high to produce biofuel. The steps used in this research is a 7 days cultivation, harvesting, extraction using hexane, and fatty acid identification using Gas Chromatography of microalgae species. Fatty acid component in some species such as Chlorella sp., Scenedesmus sp., Nannochloropsis sp., and Isochrysis sp. is between 0.21-29.5%; 0.11-25.16%; 0.30-42.32%; 2.06-37.63%, respectively, based on dry weight calculation. The high content of fatty acid in some species of microalgae showed the potential to be the feedstock of producing biofuel in overcoming the limited utilization from petroleum (fossil fuel) presently.
Coral reef communities contain a wide variety of mutualistic associations none more important than the relationship between corals and their symbiotic dinoflagellates of the genus Symbiodinium sp., commonly referred to as zooxanthellae. The function of Zinc (Zn) as cofactor of several enzyme systems such as extracellular carbonic anhydrase (extracellular CA) which catalyzes the interconversion of HCO3- and CO2. Concentrations of dissolved Zn in oligothropic waters are often very low therefore ma WIDIASTUTI KARIM; RICHARDUS KASWADJI; TRI PRARTONO; LILY MARIA GORETTI PANGGABEAN
HAYATI Journal of Biosciences Vol. 18 No. 4 (2011): December 2011
Publisher : Bogor Agricultural University, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.4308/hjb.18.4.157

Abstract

Coral reef communities contain a wide variety of mutualistic associations none more important than the relationship between corals and their symbiotic dinoflagellates of the genus Symbiodinium sp., commonly referred to as zooxanthellae. The function of Zinc (Zn) as cofactor of several enzyme systems such as extracellular carbonic anhydrase (extracellular CA) which catalyzes the interconversion of HCO3- and CO2. Concentrations of dissolved Zn in oligothropic waters are often very low therefore may limit the growth of zooxanthellae and their ability to fix CO2 from seawater via the carbonic anhydrase. The aim of this research is to investigate the effect of various concentrations of Zn on the growth and extracellular CA activity in zooxanthellae. Cell density was monitored daily by enumeration with hemocytometer-type chamber (0.1 mm). Extracellular CA was measured in homogenized intact whole cell by a pH drift assay. Results revealed that Zn status strongly influences the growth rate and extracelullar CA activity in zooxanthellae. The specific growth rate and cell density increased two-fold whilst extracelullar CA activity increased 10.5 times higher than that in control with increasing concentrations of Zn from 0 to 80 nM, but decreased when Zn was over 80 nM. Under a concentration of 80 nM was not Zn limited culture, consequently the growth rate of zooxanthellae not dependent on CO2 concentration yet offset by extracelullar CA activity.
Marine Microalgae Tetraselmis suecica as Flocculant Agent of Bio-flocculation Method Mujizat Kawaroe; Tri Prartono; Adriani Sunuddin; Deni Saputra
HAYATI Journal of Biosciences Vol. 23 No. 2 (2016): April 2016
Publisher : Bogor Agricultural University, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1035.711 KB) | DOI: 10.4308/hjb.23.2.62

Abstract

Microalgae harvesting is an important part in microalgae cultivation system. Techniques for harvesting marine microalgae which are commonly used are centrifugation, filtration and flocculation. These techniques still have some disadvantages, such as not environment friendly, and high usage of energy and cost. Bio-flocculation harvesting technique using microalgae as a flocculant agent can be an alternative way to solve these problems. In this research, mixing of Tetraselmis suecica (flocculant) with Chlorellasp. and Nannochloropsis sp. (non-flocculant) in ratios of 1:4, 2:4, 3:4 and 4:4 (v/v) has been conducted to obtain percent recovery of marine microalgae harvest. The results showed that T. suecica as flocculant agent can fasten the harvesting of Chlorella sp. and Nannochloropsis sp. It was shown by the increase of percent recovery value of Chlorellasp. from 51.14 ± 1.07% to 67.34 ± 0.67% and Nannochloropsis sp. from 20.52 ± 1.17% to 42.43 ± 0.40% during the first hour of flocculating process. Our result showed that bio-flocculation is an environment friendly technique which can be applied to harvest marine microalgae.
Co-Authors . Riska Abdullah Hisam bin Omar Achyani, Ratno Adriani Sunuddin Agus Atmadipoera Agus S Atmadipoera Alan Frendy Koropitan Albida Rante Tasak Ali Arman Ali Arman Ali Arman Ali Arman Ali Arman Ali Arman Lubis Ali Arman Lubis Amir Yarkhasy Yuliardi Andi Agussalim, Andi Angga Dwinovantyo Ani Haryati, Ani Anma Hari Kusuma Anna Ida Sunaryo Purwiyanto Anna Ida Sunaryo Purwiyanto Asmika Harnalin Simarmata Bengen, Detriech G Beta Susanto Barus Beta Susanto Barus Bibiana W. Lay Bintal Amin Chandrika Eka Larasati Dafit Ariyanto DAHLIA WULAN SARI Dea Fauzia Lestari, Dea Fauzia Dedi Soedarma Dedi Soedarma Deni Saputra Dewi S. Ariesta Dewy Septiyanti Yolanda Dietrich G Bengen Dietriech G Bengen Dietriech Geoffrey Bengen Dina Augustine DINA AUGUSTINE DWI ANDREAS SANTOSA Dwi Hindarti Dwi Hindarti, Dwi Dwiyoga Nugroho Efriyeldi, Efriyeldi Enan M. Adiwilaga Etty Riani Fadli Syamsudin Fadli Syamsudin Febrianto, Muhammad Riza Hanief Ganjar Saefurahman Hadi Hermansyah Hadi Hermansyah Harpasis S Sanusi Harpasis s. Sanusi Harpasis S. Sanusi Harpasis S. Sanusi Harpasis S. Sanusi Harpasis Slamet Sanusi Hartanto, Mochamad Tri Heron Surbakti Hilda Zulkifli Hilda Zulkifli Hilda Zulkifli I Wayan Nurjaya Imalpen Imalpen Imalpen, Imalpen Indra Jaya Indra Jaya Intan Sari Dewi, Intan Sari Irzal Effendi Iswandi Wahab Kolibongso, Duaitd Kusumaningsih, Alvianita Lestari LILY MARIA GORETTI PANGGABEAN Mai Suriani Mardiansyah Mardiansyah, Mardiansyah Martinez, Stepahnie J. Mohammad Agung Nugraha Mohammad Agung Nugraha Mohammad Khotib Mohammad Tri Hartanto Muhamad Riza Kurnia Lubis Muhammad Trial Fiar Erawan Mujizat Kawaroe Mujizat Kawaroe MUJIZAT KAWAROE Mujizat Kawaroe MUJIZAT KAWAROE Mujizat Kawaroe Mulia Purba Najamuddin N Nella Tri Agustini, Nella Tri Neviaty P Zamani Neviaty P. Zamani Nico Wantona Prabowo Nuchsin, Ruyitno Paputungan, Mohammad Sumiran Puradiredja, Sena Pasha Rastina Rastina, Rastina Restya Rahmaniar RICHARDUS KASWADJI RIDWAN AFFANDI Rina Zuraida Rina Zuraida Riris Aryawati Riris Aryawati Robinson Sitepu Ruyitno Ruyitno Salsabila, Afviya Salsabilah, Raisyah Santi Susanti Santi Susanti Santi Susanti, Santi Syahrial Syahrial Syahrial Syahrial Syahrial Syahrial Taslim Arifin WIDIASTUTI KARIM Wike Ayu Eka Putri Yani Permanawati Yeti Darmayati Yeti Darmayati Yuanpin Chang Yunita A. Noya Yusli Wardiatno Zainal Arifin Zaki, Nurul Hidayah Mat