Growth Characteristic, Mono-strain Mass Culture and Antioxidant Effects of Two Benthic Diatoms Amphora coffeaeformis and Achnanthes longipes from Korea

Abu Affan,Rohan Karawita,You-Jin Jeon,Joon-Baek Lee,Do-Hyung Kang,Heung-Sik Park 한국해양바이오학회 2007 한국해양바이오학회지 Vol.2 No.3

Seasonal cycle of phytoplankton in aquaculture ponds in Bangladesh

Abu Affan,Joon-Baek Lee,Saleha Khan,Mahfuzul Haque,Abu Syed Jewel 한국조류학회I 2005 ALGAE Vol.20 No.1

A study on the seasonal changes in the phytoplankton community was carried out in four aquaculture ponds of Bangladesh over a period of 16 months from August 2000 to November 2001. Out of 45 phytoplankton species identified, 30 belong to Cyanophyceae, 7 to Chlorophyceae, 5 to Bacillariophyceae and 3 to Euglenophyceae. The highest phytoplankton abundance was observed in spring followed by early autumn, summer, and the lowest was in winter. The annual succession of Cyanophyceae was characterized by spring and early autumn period dominated by Microcystis sp. Anabaena sp. and Planktolymbya sp. with Microcystis sp. as the main blue-green algae represented. Chlorophyceae was characterized by rainy season domination of Chlorella vulgaris, Pediastrum sp. and Scenedesmus denticulatus with maximum abundance of Chlorella vulgaris. Whereas Bacillariophyceae was dominant during the winter period. Navicula angusta and Cyclotella meneghiniana were the most frequently occurring species of Bacillariophyceae throughout the study period. Euglenophyceae was dominant in late autumn and Euglena sp. was the dominant species. The effect of various physicochemical water quality parameters on the seasonal distribution and succession of the above mentioned phytoplankton population as well as the interaction and eutrophication are discussed.

Seasonal Characteristics of Phytoplankton Dynamics and Environmental Factors in the Coast of Mara-do and U-do, Jeju Island, Korea

Affan, Abu,Lee, Joon-Baek The Korean Society of Phycology 2004 ALGAE Vol.19 No.3

A study on seasonal characteristics of phytoplankton dynamics and environmental factors was carried out at four stations including Mara-do and U-do located in the western and eastern coast of Jeju Island in southern Korea from April 2003 to March 2004. Out of 101 phytoplankton species identified, 84 belong to Bacillariophyceae, 9 Dinophyceae, 6 phytoflagellates and 2 coccolithophorids, and the highest value of species diversity was observed in April. Phytoplankton was more abundant at the western coast than at the eastern coast from March to September and its highest abundance was 49.24 ${\times}$ 10$^3$ cells L$^{-1}$ at Mara-do in July. The pennate diatoms were more abundant at the western coast than at the eastern coast with the highest abundance of 38.75 ${\times}$ 10$^3$ cells L$^{-1}$ at Mara-do in July, and during this period Nitzschia longissima contributed 68.5% of the total phytoplankton abundance. Naviculaceae was more abundant at Gosan (western coast) in November when Stauroneis membranacea represented 80.1% of the abundance. Leptocylindrus dances contributed 49.4% of the abundance at U-do in November. Dinophyceae was more abundant at U-do in August. Water temperature and pH fluctuated from 11.7${^{\circ}C}$ to 27.1${^{\circ}C}$ and from 7.31 to 8.70, respectively. Water temperature of Mara-do was about 1-2${^{\circ}C}$ higher than the other stations. Salinity varied from 30.4 to 35.0 psu with the minimum in rainy season and the maximum at the end of winter. The concentration of NH$_4$-N, NO$_3$-N, NO$_2$-N, PO$_4$-P and SiO$_2$-Si ranged 0.07-6.79, 1.0-62.0, 1.0-8.0, 1.0-7.0 and 7.0-191.0 $\mu$g-at L$^{-1}$, respectively. Chlorophyll a concentrations varied from 0.10 to 1.17 $\mu$g L$^{-1}$. NH$_4$-N concentrations were high at U-do from May to December, and at Mara-do from January to February. The high concentrations of NO$_3$-N were found at Mara-do from June to September and at U-do from January to May. The effects of various physicochemical parameters on the seasonal distribution and succession of phytoplankton population suggest that there is a classical pattern of phytoplankton dynamics in Jeju coastal waters.

Seasonal Cycle of Phytoplankton in Aquaculture Ponds in Bangladesh

Affan, Abu,Jewel, Abu Syed,Haque, Mahfuzul,Khan, Saleha,Lee, Joon-Baek The Korean Society of Phycology 2005 ALGAE Vol.20 No.1

A study on the seasonal changes in the phytoplankton community was carried out in four aquaculture ponds of Bangladesh over a period of 16 months from August 2000 to November 2001. Out of 45 phytoplankton species identified, 30 belong to Cyanophyceae, 7 to Chlorophyceae, 5 to Bacillariophyceae and 3 to Euglenophyceae. The highest phytoplankton abundance was observed in spring followed by early autumn, summer, and the lowest was in winter. The annual succession of Cyanophyceae was characterized by spring and early autumn period dominated by Microcystis sp. Anabaena sp. and Planktolymbya sp. with Microcystis sp. as the main blue-green algae represented. Chlorophyceae was characterized by rainy season domination of Chlorella vulgaris, Pediastrum sp. and Scenedesmus denticulatus with maximum abundance of Chlorella vulgaris. Whereas Bacillariophyceae was dominant during the winter period. Navicula angusta and Cyclotella meneghiniana were the most frequently occurring species of Bacillariophyceae throughout the study period. Euglenophyceae was dominant in late autumn and Euglena sp. was the dominant species. The effect of various physicochemical water quality parameters on the seasonal distribution and succession of the above mentioned phytoplankton population as well as the interaction and eutrophication are discussed.

Seasonal Dynamics of Phytoplankton and Environmental Factors around the Chagwi-do off the West Coast of Jeju Island, Korea

Affan, Abu,Lee, Joon-Baek,Kim, Jun-Teck,Choi, Young-Chan,Kim, Jong-Man,Myoung, Jung-Goo The Korean Society of Oceanography 2007 Ocean science journal Vol.42 No.2

The dynamics of phytoplankton abundance with seasonal variation in physicochemical conditions were investigated monthly at 10 stations around the Chagwi-do off the west coast of Jeju Island, Korea, including inshore, middle shore, and offshore in the marine ranching are a from September 2004 to November 2005. Water temperature varied from 12.1 to $28.9^{\circ}C$ (average $18.8^{\circ}C$), and salinity from 28.9 to 34.9 psu (average 33.7 psu). The chlorophyll a concentration was $0.02-2.05\;{\mu}g\;L^{-1}$ (average $0.70\;{\mu}g\;L^{-1}$), and the maximum concentration occurred in the bottom layer in April. A total of 294 phytoplankton species belonging to 10 families was identified: 182 Bacillariophyceae, 52 Dinophyceae, 9 Chlorophyceae, 12 Cryptophyceae, 6 Chrysophyceae, 4 Dictyophyceae, 13 Euglenophyceae, 6 Prymnesiophyceae, 5 Prasinophyceae, and 5 Raphidophyceae. The standing crop was $2.21-48.69\times10^4\;cells\;L^{-1}$ (average $9.23\times10^4\;cells\;L^{-1}$), and the maximum occurred in the bottom layer in April. Diatoms were most abundant throughout the year, followed by dinoflagellates and phytoflagellates. A phytoplankton bloom occurred twice: once in spring, peaking in April, and once in autumn, peaking in November. The spring bloom was represented by four Chaetoceros species and Skeletonema costatum; each contributed 10-20% of the total phytoplankton abundance. The autumn bloom comprised dinoflagellates, diatoms, and phytoflagellates, of which dinoflagellates were predominant. Gymnodinium conicum, Prorocentrum micans, and P. triestinum each contributed over 10% of the total phytoplankton abundance.

GROWTH CHARACTERISTICS AND ANTIOXIDANT PROPERTIES OF THE BENTHIC DIATOM <i>NAVICULA INCERTA</i> (BACILLARIOPHYCEAE) FROM JEJU ISLAND, KOREA¹

Affan, Abu,Karawita, Rohan,Jeon, You-Jin,Lee, Joon-Baek Blackwell Publishing Ltd 2007 Journal of phycology Vol.43 No.4

<P>Benthic diatoms are a commonly used food source in shellfish aquaculture. Diatoms of the genus <I>Navicula</I> are the most abundant benthic diatoms occurring year-round on the coast of Jeju Island, Korea. We isolated an axenic strain of <I>N. incerta</I> Grunow; estimated its growth characteristics under 27 different combinations of temperature, salinity, and nutrients; and determined its biochemical composition and antioxidant activities. The maximum specific growth rate (&mgr;<SUB>max</SUB>), defined as the increase in cell density per unit time, was 0.81–1.04 · d<SUP>−1</SUP>, and the maximum cell density, 7.99 × 10<SUP>5</SUP> cells · mL<SUP>−1</SUP>, was reached at 0.88 · d<SUP>−1</SUP> &mgr;<SUB>max</SUB>, 20°C, 30 psu salinity, and F/2 nutrient concentration on day 12 of the culture period. The approximate cellular composition was as follows: 7.0 ± 0.04% protein, 1.7 ± 0.28% lipid, 12.8 ± 0.85% carbohydrate, 68.4 ± 0.09% ash, and 10.1 ± 0.44% moisture. The antioxidant properties of <I>N. incerta</I> were determined for various extracts. The rates of 1,1-diphenyl-2-picrylhydrazyl (DPPH) free-radical scavenging for Neutrase and methanol extracts were 81.6% and 62.8%, respectively. Flavourzyme extract had a superoxide-scavenging rate of 57.7%. Kojizyme and Ultraflo extracts had nitric-oxide-scavenging rates of 42.2% and 40.6%, respectively, significantly higher than commercial antioxidants, such as &agr;-tocopherol and butylated hydroxytoluene (BHT). The metal-chelating activities of the methanol, Neutrase, and Termamyl extracts were 68.5%, 45.2%, and 41.2%, respectively, four to six times higher than commercial antioxidants. The Termamyl extract showed the highest linoleic acid peroxidation inhibition, exceeding &agr;-tocopherol and on par with BHT.</P>

Seasonal Dynamics of Phytoplankton and Environmental Factors around the Chagwi-do off the West Coast of Jeju Island, Korea

Abu Affan,Joon-Baek Lee,Jun-Teck Kim,Young-Chan Choi,Jong-Man Kim,Jung-Goo Myoung 한국해양과학기술원 2007 Ocean science journal Vol.42 No.2

The dynamics of phytoplankton abundance with seasonal variation in physicochemical conditions were investigated monthly at 10 stations around the Chagwi-do off the west coast of Jeju Island, Korea, including inshore, middle shore, and offshore in the marine ranching area from September 2004 to November 2005. Water temperature varied from 12.1 to 28.9°C (average 18.8°C), and salinity from 28.9 to 34.9 psu (average 33.7 psu). The chlorophyll a concentration was 0.02–2.05 g L–1 (average 0.70 g L–1), and the maximum concentration occurred in the bottom layer in April. A total of 294 phytoplankton species belonging to 10 families was identified: 182 Bacillariophyceae, 52 Dinophyceae, 9 Chlorophyceae, 12 Cryptophyceae, 6 Chrysophyceae, 4 Dictyophyceae, 13 Euglenophyceae, 6 Prymnesiophyceae, 5 Prasinophyceae, and 5 Raphidophyceae. The standing crop was 2.21–48.69×104 cells L–1 (average 9.23× 104 cells L–1), and the maximum occurred in the bottom layer in April. Diatoms were most abundant throughout the year, followed by dinoflagellates and phytoflagellates. A phytoplankton bloom occurred twice: once in spring, peaking in April, and once in autumn, peaking in November. The spring bloom was represented by four Chaetoceros species and Skeletonema costatum; each contributed 10–20% of the total phytoplankton abundance. The autumn bloom comprised dinoflagellates, diatoms, and phytoflagellates, of which dinoflagellates were predominant. Gymnodinium conicum, Prorocentrum micans, and P. triestinum each contributed over 10% of the total phytoplankton abundance.

Growth Characteristic, Mono-strain Mass Culture and Antioxidant Effects of Two Benthic Diatoms Amphora coffeaeformis and Achnanthes longipes from Korea

Abu Affan, Md.,Karawita, Rohan,Jeon, You-Jin,Lee, Joon-Baek,Kang, Do-Hyung,Park, Heung-Sik The Korean Society for Marine Biotechnology 2007 한국해양바이오학회지 Vol.2 No.3

Amphora coffeaeformis and Achnanthes longipes are commonly found as dominant benthic microalgae in Jeju coastal water throughout the year. In order to investigate pharmaceutical uses of these diatoms, each single species was isolated with micropipette under phase contrast microscope and subcultured with synthetic seawater media which was enriched with F/2 media, trace metal solution and $Na_2SiO_3$). Growth characteristics of these species were also determined with different combination of salinity, nutrients concentration and temperature. Thereafter, mass culture of each species was done based on the maximum growth condition. Biomass was collected after two weeks of mass culture and freeze dried for antioxidant study. The antioxidant properties of different fractions (n-hexane, chloroform and ethylacetate) obtained by solvent fractionation of 80% methanolic extract of two microalgae were investigated for free radical, reactive oxygen species scavenging (Super oxide, Hydrogen peroxide, Hydroxyl radical and Nitric oxide), metal chelating and lipid peroxidation inhibition activities. All fractions of A. longipes showed higher $DPPH^{\cdot}$ (free radical) scavenging activities (n-hexane: 89.0%, Chloroform: 76.0%, Ethylacetate: 66.0%, Methanol: 90.6% and aqueous residue: 63.0%). N-hexane fraction of A. longipes showed significantly higher activity (49.0%) on nitric-oxide. Ethylacetate fraction of A. longipes and aqueous residue of A. coffeaeformis exhibited 64.0% and 75.6% metal chelating activity which was higher than commercial antioxidants (${\alpha}$-tocopherol: 18.0% and BHT: 16.0%). The n-hexane fraction of A. coffeaeformis had 67.5% activity on $DPPH^{\cdot}$. Chloroform and n-hexane fractions of A. coffeaeformis exhibited 46.2% and 47.6% $H_2O_2$ scavenging effects which were closely similar to commercial antioxidants (${\alpha}$-tocopherol: 49.2% and BHT: 58.6%). Chloroform and ethylacetate fractions of A. longipes and fraction of n-hexane and chloroform of A. coffeaeformis showed better lipid peroxidation activities than ${\alpha}$-tocopherol. These data suggest that both organic and aqueous fractions have good antioxidative compounds with different antioxidant properties.

Seasonal Characteristics of Phytoplankton Dynamics and Environmental Factors in the Coast of Mara-do and U-do, Jeju Island

Md.Abu Affan,이준백 한국조류학회I 2004 ALGAE Vol.19 No.3

실외 배양 조건에서 요소를 첨가한 배지 성분에 따른 Spirulina (Arthrospira) platensis의 성장 비교

이대원,Affan Md Abu,이현용,마채우,박흥식,권문상,강도형 한국해양과학기술원 2013 Ocean and Polar Research Vol.35 No.4

One of the most important challenges facing the Spirulina mass cultivation industry is to find a way to reduce the high production costs involved in production. Although the most commercial medium (Zarrouk’s medium) for Spirulina cultivation is too expensive to use, it contains higher amount of NaHCO3 (16.80 g L−1), trace metals and vitamin solutions. The purpose of this study was to increase the efficiency of Spirulina platensis biomass production by developing a low-cost culture medium at an isolated tropical island such as Chuuk State, Federated States of Micronesia (FSM). This study set out to formulate a lowcost medium for the culture of S. platensis, by substituting nutrients of Zarrouk’s medium using fertilizer grade urea and soil extract with a different concentration of carbon source under natural weather condition. In order to select a low-cost culture medium of S. platensis, 10 culture media were prepared with different concentrations of nitrogen (urea and NaNO3) and NaHCO3. The highest maximum specific growth rate (μmax) and mass production were 0.50 day−1 and 1.05 g L−1 in modified medium (NaHCO3 7.50 g L−1, urea 2.00 g L−1 without NaNO3) among all the synthesized media. Protein (56.14%) and carbohydrate (16.21%) concentrations of the lyophilized standard samples were estimated with highest concentration of glutamic acid (14.93%). This study revealed that the use of a low concentration of urea and NaHCO3 with soil extract was an affordable medium for natural mass cultivation in the FSM.