The phytohormone abscisic acid increases triacylglycerol content in the green microalga Chlorella saccharophila (Chlorophyta)

Contreras-Pool, Patricia Yolanda,Peraza-Echeverria, Santy,Ku-Gonzalez, Angela Francisca,Herrera-Valencia, Virginia Aurora The Korean Society of Phycology 2016 ALGAE Vol.31 No.3

Microalgae are currently a very promising source of biomass and triacylglycerol (TAG) for biofuels. In a previous study, we identified Chlorella saccharophila as a suitable source of oil for biodiesel production because it showed high biomass and lipid content with an appropriate fatty acid methyl esters profile. To improve the TAG accumulation in C. saccharophila, in this study we evaluated the effect of abscisic acid (ABA) addition on cell concentration, lipid content and TAG production in this microalga. First, we evaluated the effects of four ABA concentrations (1, 4, 10, and 20 μM) added at the beginning of a single-stage cultivation strategy, and found that all concentrations tested significantly increased cell concentration and TAG content in C. saccharophila. We then evaluated the addition of 1 μM ABA during the second stage of a two-stage cultivation strategy and compared it with a nitrogen deficiency treatment (ND) and a combination of ND and ABA (ND + ABA). Although ABA alone significantly increased lipid and TAG contents compared with the control, ND showed significantly higher TAG content, and ND + ABA showed the highest TAG content. When comparing the results of both strategies, we found a superior response in terms of TAG accumulation with the addition of 1 μM ABA at the beginning of a single-stage cultivation system. This strategy is a simple and effective way to improve the TAG content in C. saccharophila and probably other microalgae as a feedstock for biodiesel production.

The phytohormone abscisic acid increases triacylglycerol content in the green microalga Chlorella saccharophila (Chlorophyta)

Patricia Yolanda Contreras-Pool,Santy Peraza-Echeverria,Ángela Francisca Ku-González,Virginia Aurora Herrera-Valencia 한국조류학회I 2016 ALGAE Vol.31 No.3

Microalgae are currently a very promising source of biomass and triacylglycerol (TAG) for biofuels. In a previous study, we identified Chlorella saccharophila as a suitable source of oil for biodiesel production because it showed high biomass and lipid content with an appropriate fatty acid methyl esters profile. To improve the TAG accumulation in C. saccharophila, in this study we evaluated the effect of abscisic acid (ABA) addition on cell concentration, lipid content and TAG production in this microalga. First, we evaluated the effects of four ABA concentrations (1, 4, 10, and 20 μM) added at the beginning of a single-stage cultivation strategy, and found that all concentrations tested significantly increased cell concentration and TAG content in C. saccharophila. We then evaluated the addition of 1 μM ABA during the second stage of a two-stage cultivation strategy and compared it with a nitrogen deficiency treatment (ND) and a combination of ND and ABA (ND + ABA). Although ABA alone significantly increased lipid and TAG contents compared with the control, ND showed significantly higher TAG content, and ND + ABA showed the highest TAG content. When comparing the results of both strategies, we found a superior response in terms of TAG accumulation with the addition of 1 μM ABA at the beginning of a single-stage cultivation system. This strategy is a simple and effective way to improve the TAG content in C. saccharophila and probably other microalgae as a feedstock for biodiesel production.

Antibacterial compounds in green microalgae from extreme environments: a review

Little, Shannon M.,Senhorinho, Gerusa N.A.,Saleh, Mazen,Basiliko, Nathan,Scott, John A. The Korean Society of Phycology 2021 ALGAE Vol.36 No.1

Increased proliferation of bacterial resistance to antibiotics is a critical issue that has increased the demand for novel antibacterial compounds. Antibacterial activities have been evaluated in extracts from photosynthetic green microalgae, with varying levels of subsequent potential for development based on the strain of algae, strain of bacterial pathogen, and solvent used to extract the metabolites. Green microalgae from extreme environmental conditions have had to adapt to conditions that exclude many other organisms. The production of antibacterial compounds aids directly or indirectly in the survival of green microalgae in these extreme environments, as well as potentially serve other roles. This review investigates antibacterial activities of green microalgae from both extreme in-situ environmental conditions and induced extreme laboratory conditions and highlights.

Absorption of CO2byMicroalgaeandItsConversiontoGreenDieselFuel

( Rahmania Admirasari ),( Zeily Nurrachman ),( Agusrifai ),( Sabaruddin W T Jokrokusumo ),( Arif Dwi Santoso ),( Akira Lusia ),( Listyani Purwitasari ),( Diyono ),( Kardono ) 경남대학교 신소재연구소 2012 신소재연구 Vol.24 No.-

Microalgae, microscopic organisms growing on water habitation actually contain chemical structures that can be utilized as a bio-fuel (bio-diesel). These types of plants are considered to be a potential candidate for green and renewable energy resources. Microalgae are also considered having characteristics of carbon neutral due to the high ability to absorb green house gas of carbon dioxide (CO2) during their photosynthesis. Moreover, microalgae cause no land use conflict unlike other bio-fuels based food plants. This paper presents the experimental results of biologically CO2 uptake by cultured microalgae through a pilot scale of an integrated photo-bioreactor (PBR). Besides, micro-algal biomass conversion into biodiesel fuel is also presented in this paper. Micro-algal PBR employed was a Single Tubular Airlift Photo-bioreactor (STAP) type developed by the Environmental Technology Center, Agency for the Assessment and Application of Technology (PTL-BPPT) with a volume of 40 liters. During a 10 day experiment, a 40 L- STAP could absorb 23 grams of CO2per day and produce 147.5 grams of wet basis or 29.5 grams of dry basis of micro-algal biomass. Thus, the CO2 uptake capacity by microalgae in this experiment was about 0.78 grams of CO2 per gram of dry micro-algal biomass. This micro-algal biomass was then converted to biodiesel oil through a process of extraction and trans-esterification which produced about 27 ml of oil. Uptake capacity of CO2by microalgae through STAP and ratio of micro-algal biomass conversion to biodiesel from this experiment were considered to be relatively low however the integrated processes consisting of the CO2 uptake by microalgae, micro-algal biomass harvesting technique and micro-algal biomass conversion to biodiesel have indicated a good system and therefore it is quite promising to be developed to a larger scale.

해양미세조류의 라디칼소거활성 검색

최진석,이원갑,김동수,최홍대,최재수,정지형,임광식,최원철,손병화,Choi, Jin-Seok,Lee, Won-Kap,Kim, Dong-Soo,Choi, Hong-Dae,Choi, Jae-Sue,Jung, Jee H.,Im, Kwang-Sik,Choi, Won-Chul,Son, Byeng-Wha 한국생약학회 2000 생약학회지 Vol.31 No.2

In order to screen new radical scavenging principle which is expected to be antiaging drug lead, we have investigated 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of the marine microalgae, greenalgae(10 speices), diatom (10 speices) and blue-green algae (10 speices). The significant activities$(IC_{50}:\;<100\;{mu}g/ml)$ were observed in 4 species of green algae (MA002, 006, 009, 010), 1 species of diatom (MA015) and 5 species of blue-green algae (MA017, 018, 019, 024, 025). Within the scope of family tested, MA009 $(IC_{50}:\;=78\;{mu}g/ml)$, MA015 $(IC_{50}:\;=38\;{mu}g/ml)$ and MA019 $(IC_{50}:\;=41\;{mu}g/ml)$ displayed the most significant activity. Among the marine microalgae tested at family level, cyanophycean blue-green algae was shown to be the most active family on screening of new bioactive compounds.

α-Fe2O3 anchored on porous N doped carbon derived from green microalgae via spray pyrolysis as anode materials for lithium ion batteries

권기민,김인겸,이관영,김한성,김문석,조원일,최재영,나인욱 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.69 No.-

The α-Fe2O3@nitrogen doped carbon (as donated α-Fe2O3@NC) composites derived from green microalgae was synthesized using one-pot spray pyrolysis, which showed a high discharge capacity of 1281.5 mAh g−1 at 100 mA g−1 as anode materials for lithium ion storage. They also provided good rate performance in a range of 200 mA g−1–1000 mA g−1, and maintained a capacity of 92% after 100 cycles at 200 mA g−1. It demonstrated not only improved electrical conductivity but also effective prevention of the volume expansion of iron oxide during battery charge/discharge by uniformly forming iron oxide nanoparticles on microalgae via spray pyrolysis.

Antioxidant and Anticancer Activities of Methanolic Extracts from Indigenous Freshwater Green Microalgae

Z-Hun KIM,Kyung June YIM 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.10

In this study, antioxidant and anticancer activities of methanolic extracts from newly isolated freshwater microalgae were investigated. First, four microalgal strains in Korea were identified as Mychonastes sp. 246, Mychonastes sp. 247, Mychonastes pushpae 248, and Mychonastes sp. 249 through 5.8S-ITS2 gene sequencing and their carotenoid contents were analyzed. Then, we accessed antioxidant and anticancer activities of microalgal methanolic extracts by DPPH radical scavenging and CCK-8 assay, respectively. We found that the genus Mychonastes contained 226~2,607 ㎎/g, 138~1,594 ㎎/g, and 126~339 ㎎/g of b-carotene, lutein, and zeaxanthin, respectively. All of the microalgal extracts showed increased antioxidant and anticancer activities in a dose-dependent manner. Antioxidant activities of the extracts were 31±7%, 27±8%, 23±7%, and 17±8%, respectively, when treated with 50 ㎎/mL. In addition, the microalgal extracts could effectively inhibit growth of all tested A549, BxPC-3, HepG2, and SKOV-3 cancer cells ranged from 16% to 62% when treated with 200 ㎎/mL. These results indicated the methanolic extract of four strain of genus Mychonastes could be used as a potential natural material as pharmaceutical ingredients.

Green remediation of nitrate and phosphate pollution using microalgae (Scenedesmus regularis): NMR fingerprinting of metabolites shift for downstream application of microalgae

Meng Shien GOH,Nyuk Ling MA 대한환경공학회 2019 대한환경공학회 학술발표논문집 Vol.2019 No.-

Offshore Cultivation of a Green Microalga, Tetraselmis sp. MBEyh04Gc, in Tubular Module Photobioreactors with CO₂

조용희,신동우,박재훈,임상민,이철균 한국공업화학회 2018 한국공업화학회 연구논문 초록집 Vol.2018 No.0

The production of biofuels using microalgae can reduce inappropriate usage of fossil fuels to results in environment problems such as air pollution and global warming. Also, microalgal cultivation in the ocean could reduce large portion of energy needed to regulate mixing, light, and temperature condition. In this study, Tetraselmis sp. MBEyh04Gc was cultivated and the effect of CO₂ filling frequency was investigated in offshore cultivation using tubular module photobioreactors (TMPBRs). As the results, biomass concentration and biomass productivity were 0.78 g L^-1 and 6.8 g m-2 d^-1 in the PBRs filled with CO₂ every 3 days. In the PBRs filled with CO₂ every 6 days, biomass concentration and biomass productivity were significantly increased to 3.18 g L^-1 and 12.6 g m^-2 d^-1. The results indicate that CO₂ filling frequency should be considered to improve the biomass concentration by maintaining the pH of culture within optimal range for maximal biomass productivity.

신규 분리된 담수미세조류 Parachlorella sp.의 지방산 생산성 향상을 위한 배지 조성 연구

박한울 ( Hanwool Park ),임경준 ( Kyung June Yim ),민지호 ( Ji-ho Min ),강성모 ( Sung-mo Kang ),한찬우 ( Chan-woo Han ),이창수 ( Chang-soo Lee ),정지영 ( Ji Young Jung ),홍성주 ( Seong-joo Hong ),이철균 ( Choul-gyun Lee ),김지훈 ( 한국미생물 · 생명공학회 2020 한국미생물·생명공학회지 Vol.48 No.3

본 연구에서는 국내 낙동강 수계에서 신규하게 분리된 미세조류인 Parachlorella sp. 종의 바이오매스 및 지방산 생산성에 대한 배지의 영향을 연구하였다. 미세조류 배양에 통상적으로 사용되는 BG-11, TAP, BBM 배지를 사용하여 바이오매스 생산성은 TAP 배지에서, 지방산 축적은 BBM 배지에서 가장 잘 일어나는 것으로 확인되었고, 지방산 생산성을 향상시키기 위해 암모니아와 아세트산을 사용하는 TAP 배지의 조성을 변화하여 BBM 배지처럼 지방산 축적을 유도하며 바이오매스 생산성을 증가시킨 MTAP 배지를 개발하였다. 전체적인 바이오매스와 지방산 생산성을 높이기 위해서는 MTAP-1 배지가 적합하여 바이오매스 생산성과 지방산 생산성은 기존의 TAP 배지 대비 각각 14%, 45% 증가하였다. 생리 활성 효과로 인해 관심도가 높은 오메가-3 지방산의 생산에는 MTAP-4 배지가 가장 적합하여 바이오매스 생산성과 오메가-3 지방산 생산성이 기존 BBM 배지 대비 각각 18%, 39% 증가하여 목표 중점 생산물질(바이오매스, 총 지방산, 또는 오메가-3 지방산)의 생산성을 향상시킬 수 있는 신규 배지 2종의 조성을 개발하였다. Parachlorella sp. is an efficient fatty acid producer that can be used in the production of biofuels, feeds, and fertilizers. Microalgae show varying responses to culture conditions, even those within the same species. In this study, growth and fatty acid composition of a newly isolated Parachlorella sp. from the Nakdong river of Korea in different culture media were investigated. The microalga was cultivated in 400 ml bubble column photobioreactors using BG-11, BBM, TAP, and modified TAP (MTAP) media. It was shown that using BBM led to greater fatty acid accumulation (34%), while using TAP medium led to greater biomass productivity (0.34 g/l/day). Composition of the TAP medium was modified to have the N:P ratio of BBM while also varying concentrations of N and P to improve fatty acid productivity. One of the modified TAP media, MTAP-1 (104.8 mgN/l, 135.2 mgP/l, N:P ratio = 0.77), showed the highest fatty acid concentration of 0.69 ± 0.04 g/l, while those from TAP and BBM were 0.48 ± 0.06 g/l and 0.40 ± 0.02 g/l, respectively. The results showed that microalgal fatty acid productivity could be enhanced by changing the N:P ratio and concentrations.