Добірка наукової літератури з теми "Microalgal bioma"

Microbial communities in the world ocean are affected strongly by oceanic circulation, creating characteristic marine biomes. The high connectivity of most of the ocean makes it difficult to disentangle selective retention of colonizing genotypes (with traits suited to biome specific conditions) from evolutionary selection, which would act on founder genotypes over time. The Arctic Ocean is exceptional with limited exchange with other oceans and ice covered since the last ice age. To test whether Arctic microalgal lineages evolved apart from algae in the global ocean, we sequenced four lineages of microalgae isolated from Arctic waters and sea ice. Here we show convergent evolution and highlight geographically limited HGT as an ecological adaptive force in the form of PFAM complements and horizontal acquisition of key adaptive genes. Notably, ice-binding proteins were acquired and horizontally transferred among Arctic strains. A comparison withTaraOceans metagenomes and metatranscriptomes confirmed mostly Arctic distributions of these IBPs. The phylogeny of Arctic-specific genes indicated that these events were independent of bacterial-sourced HGTs in Antarctic Southern Ocean microalgae.

Os antimicrobianos de uso doméstico, hospitalar, veterinário e na agricultura têm despertado crescente preocupação, devido à presença desses resíduos no ambiente aquático, mesmo em concentrações muito baixas, podem potencialmente interferir no equilíbrio da biota aquática, afetando populações de produtores primários. Dos microrganismos, as microalgas são consideradas umas das mais sensíveis, além de serem mais suscetíveis, por estarem distribuídas por todo o ambiente aquático. O objetivo deste estudo foi avaliar os efeitos de substâncias antibióticas sobre o crescimento da microalga Chlorella vulgaris. Os resultados apontam que os antibióticos, Amoxilina, Ampicilina e Cefalexina monoidratada, pertencentes ao grupo beta-lactâmicos apresenta uma densidade celular superior em relação ao tratamento controle, inibindo o crescimento de C. vulgaris. O estudo sugere a realização de monitoramentos nas matrizes ambientais, principalmente da região norte, por apresentar um baixo percentual no tratamento convencional de esgotos sanitário, evitando assim, riscos sobre a biota aquática e a saúde humana.

Heavy metals (HMs) can induce both chronic and acute harmful effects on marine and freshwater biota. The environmental impact of HMs in freshwater, seawater, soil, and wastewater can be limited using microbes, including microalgae, that are able to remove metals from environmental matrices. Indeed, they can passively adsorb and actively accumulate these persistent pollutants within their organelles, limiting their detrimental effects on cellular metabolism. The Sarno River is a 30 km long freshwater stream located in Southern Italy, polluted by partially untreated municipal, agricultural, and industrial wastewaters. In spite of this, microalgal cultures from Sarno River or Sarno River Mouth have never been established. In the present study, we isolated a green algal strain from the Sarno River Mouth and determined its ability to grow in polluted seawater containing different concentrations of cadmium, lead, or zinc. This strain was found to be able to accumulate these elements within its biomass in a dose-dependent manner. Growth inhibition experiments confirm the relatively low toxicity of Cd and Pb below 50 µM, while algal growth was seriously affected in Zn-amended media. To the best of our knowledge, this is the first study focused on the ability of microalgae from Sarno River Mouth to tolerate and uptake HMs.

Industrial waste contributes the heavy metals pollution in the environment, especially in the water. One of the heavy metals that pollute the environment is lead (Pb). Lead is a substance that is harmful to organisms, especially humans, both adults and children. Solutions to tackle Pb pollution isby remediation process. Physical and chemical remediation methods usually costly and ineffective. One of the alternative methods which is used is the bioremediation uses microalgae or called as phycoremediation. One of microalgae which is used as agents of phycoremediation is Spirulina platensis Geitler because it’s easily cultured and it’s abundant in nature. This study aims to assess the population growth and the percentage reduction of Pb after inoculated with the use of Spirulina platensis Geitler. The method which is to cultivate S. platensis Geitler in brackish watermedia with a salinity of 15 ppt which have been added Pb with a concentration of 1 mg, 3 mg, and 5 mg for 8 days and observed the population and the percentage reduction of Pb heavy metals. Environmental factors such as temperature, salinity, pH, light intensity are conditioned to remain stable. After 8 days of research, study was able to reduce Pb. Each treatment has different concentrations decrease. Treatment Pb 1 mg of 0.949 into 0.603 mg / L; Pb 3 mg of 2.894 to 2.46 mg / L; and Pb 5 mg of 4.88 to 4.31 mg / L, with each percentage decline of 36%, 15% and 12%. The Pb 3 mg treatment has higher cell population (129.367 cell / ml) than control (106.600 cell/ml) while 1 mg and 5 mg treatment has 93.700 cell / ml and 93.500 cell / ml. Keywords: Spirulina platensis, phycoremediation, waste, lead.

Microalgae are organisms that contain chlorophyll and other pigments so they can carry out photosynthesis. Microalgae are widespread in nature and can be found in any environment exposed to sunlight. Microalgae are micro-sized biota with a diameter of less than 2 µm. The benefits of microalgae for other living things, especially humans, are numerous, including as a source of food and ingredients in the manufacture of medicines. Dunaliella sp. is a group of green algae that contains protein, fat and carbohydrates as a good source of food. Growth rate and density of microalgae Dunaliella sp. and the effect of lead acetate with different concentrations was observed using a microscope, starting from the lag phase, the logarithmic phase, the stationary phase and the declination phase. Dunaliella sp. Experiencing an exponential phase in the observation before treatment, namely on the 9th day and then doing the treatment. Treatment with lead acetate with concentrations of 10 ppm, 50 ppm and 80 ppm is very influential in the growth of microalgae. The result is that lead acetate contains toxins that can kill microalgae cells in both low and high concentrations.Keywords: Microalgae, Dunaliella sp., Lead Acetate, Concentration

Microalgae are photosynthetic microorganisms that are widely distributed in waters. They have the potential as an alternative source of pigments, lipids, proteins, and carbohydrates. In this study, identification and isolation of single-cell microalgae from Ambon Bay were carried out by serial dilution method and inoculation of the culture by appearance/spread on the surface of the solidified agar medium. The results showed that the waters of Ambon Bay have physical parameters such as temperature, pH, salinity, and TDS, which are still within the threshold specified in the seawater quality standard for biota. The water conditions at the 10 sampling locations had different salinity, pH, temperature, and TDS. This condition affects the distribution of microalgae in the waters in Ambon Bay. The image from light microscopy shows that there are 27 species of microalgae scattered in the waters of Ambon Bay, which belong to the classes Chlorophyceae, Flagilariophyceae, Bacillariophyceae (diatoms), Coscinodiscophyceae, and Dinophyceae. Microalgae isolation obtained five species (single-cell) including four species from the class Bacillariophyta (Navicula sp, Nitzschia sp, Cyclotella sp) and one species from the class Chlorophyta (Chlorella sp).

AbstrakPengembangan obat dan kosmetik dari biota laut kini tengah terjadi di dunia farmasi. Mikroalga Thalassiosira sp merupakan jenis mikroalga yang memiliki kandungan senyawa-senyawa bioaktif. Beberapa penelitian sebelumnya menunjukkan bawa mikroalga memiliki aktivitas antibakteri. Penelitian ini bertujuan untuk mengetahui aktivitas antibakteri dari ekstrak mikroalga Thalassiosira sp terhadap 3 bakteri yaitu staphylococcus aureus, staphylococcus epidermidis dan propionibakterium Acne di fasa n-heksan, etil asetat dan etanol. Ketiga bakteri ini dapat menyebabkan infeksi kulit. Mikroalga Thalassiosira sp dikultivasi menggunakan medium walne dan di panen pada hari ke-6 setelah penanaman. Pemanen mikroalga dilakukan dengan teknik sentrifuga. Ektrak dilakukan dengan cara maserasi bertingkat selama 3 x 24 jam. Pengujian antibakteri dilakukan dengan metode difusi kertas cakram atau metode disc diffusion menurut Kirby-Bauer. Hasil ekstrak mikroalga Thalassiosira sp diperoleh paling banyak pada ekstrak etanol sebanyak 24,24%(b/b), ektrak etil asetat sebanyak 19,75%(b/b) dan paling sedikit adalah ekstrak heksan sebanyak 8,64% (b/b). Hasil uji difusi menunjukkan ekstrak n-heksan, etil asetat dan etanol mikroalga Thalassiosira sp memiliki aktivitas terhadap bakteri staphylococcus aureus, staphylococcus epidermidis dan propionibakterium Acne yang ditunjukan dengan adanya zona bening. Kata kunci: mikroalga, Thalassiosira sp, antibakteri, infeksi kulit, metode difusi Abstract Development drugs and cosmetics from marine biota is now being happened in pharmacy word. Microalgae Thalassiosira sp is a type of microalgae that has a bioactive compounds. Several previous studies have shown the existence of microalgae which have antibacterial activity. This study aimed to study the antibacterial activity of extracts of microalgae Thalassiosira sp against 3 bacteria which is staphylococcus aureus, staphylococcus epidermidis and propionibacterium acne in the n-hexane, ethyl acetate and ethanol phases. These three bacteria can cause skin infections. Microalgae Thalassiosira sp was cultivated using walne medium and harvested on the 7th day after planting. Microalgae harvesters are carried out by centrifuge techniques. The extract is done by multilevel maceration for 3 x 24 hours. Antibacterial testing was carried out by the paper diffusion method or Kirby-Bauer's disc diffusion method. The results of the crude extract of microalgae Thalassiosira sp were obtained at most in ethanol extract as much as 24.24% (w/w), extract of ethyl acetate at 19.75% (w / w) and at least hexane extract at 8.64% (w/w). The diffusion test results for n-hexane, ethyl acetate, and ethanol microalgae Thalassiosira sp extract have activity on staphylococcus aureus, staphylococcus epidermidis and propionibacterium acne which are supported by clear zones. Keywords: mikroalge, Thalassiosira sp, antibacteria, skin infection, diffusion method

Dunaliella salina and Chlorella vulgaris is a natural feed microalgae with high carotenoid content that can be increased using protoplast fusion technique. Protoplast fusion as one of the application fields of genetic engineering is a method for obtaining recombinant with the desired properties and profitable in a short time. This study aimed to see the effect of the addition of carotenoid-rich feed results from protoplast fusion recombinant D. salina and C. vulgaris on the survival rate and weight of shrimp post larvae. Mixed fusion results feed and artificial feed needed for the growth of post-larval shrimp, moulting and skin pigmentation. The results showed that the recombinant from protoplast fusion intergenera D. salina and C. vulgaris contains carotenoid pigments higher, reaching 124.6 mg / g bks from the second parent, namely D. salina reached 101.83 mg / g bks, while C. vulgaris 97.18 ug / g bks. Feed manufacturing is done by mixing pellets and 80-100x103 cells per 0.0225 g of feed. Application of feed carried on Penaeus monodon F. (tiger prawn) stadia PL-20 for a month. The results of weight measurements showed the highest prawn post larvae reached at artificial feeding plus recombinant protoplast fusion results intergenera D. salina and C. vulgaris and was able to raise the level of post-larval shrimp survival rate reached 88%. Keywords: D. salina, C. vulgaris, Protoplast Fusion, Carotenoid, Penaeus monodon F.

Microalgae is one of the marine biota that has an important role in the waters because it acts as a supplier of food in the waters. Microalgae is a biological source that needs to be exploited because it is rich in essential compounds. Dunaliella sp. is one of the many micro algae used as research. Utilization of Dunaliella sp. quite diverse and has been marketed in developed countries because of its very attractive economic value. This study aims to determine the effects of lead acetate compounds on growth and content of chlorophyll pigments microalgae Dunaliella sp. The results obtained in this study are the lead acetate compounds can affect the number of cells in the growth of microalgae and analysis results obtained with a spectrophotometer showed that the extraction concentration of control day 5 (Exponential Phase) was higher than the concentration of 15 ppm and 25 ppm, whereas extraction on day 21 (Death Phase) concentration of 15 ppm was higher than 25 ppm.Keywords : Dunalella sp., Lead Acetate, Pigment chlorophyll RingkasanMikroalga adalah salah satu biota laut yang memiliki peran penting di perairan karena berfungsi sebagai pemasok makanan di perairan. Mikroalga adalah sumber biologis yang perlu dieksploitasi karena kaya akan senyawa esensial. Dunaliella sp. adalah salah satu dari banyak mikroalga yang digunakan sebagai penelitian. Pemanfaatan Dunaliella sp. cukup beragam dan telah dipasarkan di negara maju karena nilai ekonominya yang sangat menarik. Penelitian ini bertujuan untuk mengetahui efek senyawa timbal asetat terhadap pertumbuhan dan kandungan pigmen klorofil Dunaliella sp. Hasil yang diperoleh dalam penelitian ini adalah senyawa timbal asetat dapat mempengaruhi jumlah sel dalam pertumbuhan mikroalga, penurunan jumlah sel mengikuti konsentrasi timbal asetat yang diberikan dan hasil analisis yang diperoleh dengan spektrofotometer menunjukkan bahwa konsentrasi ekstraksi kontrol hari 5 (Fase Eksponensial) lebih tinggi daripada konsentrasi 15 ppm dan 25 ppm, sedangkan ekstraksi hari 21 (Fase Kematian) konsentrasi 15 ppm lebih tinggi dari 25 ppm.Kata kunci : Dunaliella sp., Timbal Asetat, Pigmen Klorofil

Lake Aur has many aquatic biota as well as become one of the mainstay attractions in Musi Rawas Regency. Community activities and lack of awareness of tourists on the cleanliness and importance of maintaining the lake environment have an impact on water pollution. One of the organisms that can be used as an indicator of river water quality is microalgae. The purpose of this study is to determine the types of microalgae Bacillariophyta divisions that exist in the lake Aur, Musi Rawas.The type of research used is survey research. Bacillariophyta Division consists of two classes, 6 orders, 7 families, 8 genera and 11 species. Observed environmental factors: temperature: 290C, pH: 6.7, Brightness: 115 cm and dissolved oxygen amount of: 38 mg / L. Based on the results of research and discussion, we can conclude that: the type of microalgae division bacillariophyta were found in Lake Aur namely: Cylotella sp, Eunotia sp, Eunotia pectinalis, Fragilaria croronensis, Synedra acus, Nitzschia sp, Nitzschia acicularis, Surirella sp, Surirella elegans, Pinnularia sp and Stauroneis sp.

Submitted by Vasti Diniz (vastijpa@hotmail.com) on 2017-07-31T12:25:00Z No. of bitstreams: 1 arquivototal.pdf: 2557660 bytes, checksum: 4c049fddfaa1836ee5649b7be251a121 (MD5)
Made available in DSpace on 2017-07-31T12:25:00Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2557660 bytes, checksum: 4c049fddfaa1836ee5649b7be251a121 (MD5) Previous issue date: 2014-04-30
Microalgae have a varied chemical composition with many products of interest to the food, pharmaceutical, cosmetic and energy sector, which makes them a group of high biotechnological potential. In this work some species of microalgae isolated from the Caatinga biome were studied regarding the taxonomic viewpoint and its cultivation in synthetic medium viewing to assess their ability to produce fatty acids methyl esters. Promising species for biodiesel production and essential fatty acids were also cultivable in alternative medium prepared with soil extract with vinasse, chicken manure and extract of biocompound obtained from fruits and vegetables marketed in EMPASA–PB. The acceptability for use of microalgae in human and/or animals was evaluated among agricultural workers of the semi-arid region of the state of Paraiba for the exotic species Spirulina platensis. Cultures of local species were obtained from water samples collected in various aquatic environments of the Caatinga inoculated in the Zarrouk and WC mediums, and maintained for growth in a culture chamber at 25°C ± 1°C. The isolated species were encoded and embedded in the Collection of Microalgae of the LARBIM/UFPB. A total of 24 strains of microalgae were obtained, of which 21 were identified to specific level, and 14 were grown in synthetic media to produce biomass for the fatty acids methyl esters analysis. Two local strains D39Z (Planktothrix isothrix) and D115WC (Scenedesmus acuminatus) and an exotic strain D9Z (Spirulina platensis) were cultured in the alternative mediums. Growth curves were monitored by cell counts and measurements of the in vivo fluorescence, in triplicate, and all growth parameters were analyzed for each species tested. Biomass of S. platensis growing in synthetic medium was used for the preparation of cakes, biscuits and juices used in sensory analysis of acceptability test and purchase intent for Spirulina, attended by 75 agricultural workers from the city of Frei Martinho-PB. These workers were also evaluated for their attitude about S. platensis. Differences in growth parameters were observed in cultured species, with the maximum growth constant (k) recorded in D112Z strain (Synechococcus nidulans) with 0.71 divisions.day-1, the longest duration of the exponential phase (8 days) in strains D74Z (Rhabdoderma lineare) and D133WC (Lagerheimia longiseta), and the highest biomass yield (0.75 g/L) was registered in the strain D28Z (Chlorococcum cf. hypnosporum). The highest yield of fatty acids (590.8%, compared to soybean) was recorded in strain D115WC (S. acuminatus). Strains growing in the alternative media exhibited distinct patterns of growth with higher yields in the extract of biocompounds. Acceptability rates of S. platensis higher than the expected (70%) were observed for all tested attributes (appearance, odor and texture) in three versions (wet biomass, dry biomass and foods), except for odor as “in natura” (66.12%). Regarding the intention of purchase, 88% of respondents said they would buy the product if they found them in the trade. The tests showed a positive index of internal consistency in relation to the attitudes about Spirulina, indicating that the tested farmers are open to technological innovations.
Microalgas apresentam uma composição química variada com muitos produtos de interesse à indústria alimentícia, farmacêutica, de cosméticos e setor energético, o que as tornam um grupo de elevado potencial biotecnológico. Neste trabalho foram estudadas espécies de microalgas isoladas do Bioma Caatinga do ponto de vista taxonômico, e avaliando sua capacidade de produção de ésteres metílicos de ácidos graxos mediante o cultivo das diferentes cepas em meios sintéticos. Cultivos de espécies promissoras à produção de biodiesel e de ácidos graxos essenciais também foram desenvolvidos em meios alternativos preparados com extrato de solo com vinhaça, esterco de galinha e extrato de biocomposto obtido com resíduos de hortifrutigranjeiros comercializados na EMPASA–PB. A aceitabilidade quanto ao uso de microalgas na alimentação humana e/ou animal entre trabalhadores rurais da região semiárida do estado da Paraíba foi avaliado para a espécie exótica Spirulina platensis. Os cultivos das espécies locais foram obtidos a partir de amostras de água coletadas em diversos ambientes aquáticos da Caatinga, inoculadas nos meios Zarrouk e WC e mantidas em câmara de cultura a 25°C±1ºC. As espécies isoladas foram codificadas e incorporadas ao Banco de Microalgas do LARBIM/UFPB, obtendo-se 24 cepas de microalgas, das quais 21 foram identificadas ao nível de espécie e 14 foram cultivadas em meios sintéticos visando à produção de biomassa e análises de ácidos graxos. Duas cepas locais D39Z(Planktothrix isothrix) e D115WC (Scenedesmus acuminatus) e uma cepa exótica D9Z( Spirulina platensis) foram cultivadas em meios alternativos. As curvas de crescimento foram acompanhadas por meio de contagens celulares e de medidas da fluorescência in vivo, em triplicatas, e todos os parâmetros de crescimento foram analisados para cada espécie testada. Biomassa de S. platensis cultivada em meio sintético foi usada na preparação de bolos, sucos e biscoitos utilizados na análise sensorial do teste de aceitabilidade e intenção de compra de produtos à base de Spirulina, do qual participaram 75 trabalhadores rurais do município de Frei Martinho-PB. Estes trabalhadores também foram avaliados quanto sua atitude frente à S. platensis. Diferenças nos parâmetros de crescimento foram observadas nas espécies cultivadas, sendo o valor máximo da constante de crescimento (k) registrado na cepa D112Z (Synechococcus nidulans) com 0,71 divisões/dia, a maior duração da fase exponencial (8 dias) nas cepas D74Z (Rhabdoderma lineare) e D133WC (Lagerheimia longiseta) e o maior rendimento em biomassa (0,75 g/L) na cepa D28Z (Chlorococcum cf. hypnosporum). O maior rendimento de ácidos graxos (415,65 mg/g em relação à soja) foi registrado na cepa D115WC (S. acuminatus). As cepas cultivadas em meios alternativos exibiram padrões de crescimento distintos com melhores rendimentos em extrato de biocomposto. Índices de aceitabilidade de S. platensis superiores ao esperado (70%) foram observados para todos os atributos testados (aparência, odor e textura) nas três versões (biomassa úmida, seca e em alimentos), exceto para odor na forma “in natura” (66,12%). Quanto à intenção de compra, 88% dos entrevistados afirmaram que comprariam os produtos caso os encontrassem no comércio. Os testes de atitudes evidenciaram um índice de consistência interno positivo frente à Spirulina, indicando que os agricultores testados são abertos a inovações tecnológicas.