BBM Medium Research Articles

Influence of nutrient formulations on growth, lipid yield, carbon partitioning and biodiesel quality potential of Botryococcus sp. and Chlorella sp.

The study was conducted to analyse the influence of three nutrient formulations, namely BG-11 medium, BBM and TAP medium, on growth potential and lipid yield of two microalgal genera (Botryococcus sp. and Chlorella sp.) and to study the roles of N, P and other major nutrients. The study focussed on the general patterns of starch and lipid synthesis and storage and to further assess how photosynthetic carbon partitioning into starch and lipid is altered by conditions in growth media such as N and C presence as seen in BG11 medium which are known to induce neutral lipid production and the lack of it in BBM and TAP medium. BG-11 medium performed better as compared to BBM and TAP medium in terms of biomass productivity and lipid yield. The lipid yield was highest in Botryococcus sp. (63.03% dry wt.) and Chlorella sp. (50.27% dry wt.) at 30th day of incubation. Mean biomass productivity was highest for Botryococcus in BBM medium (6.14mg/L/day) and for Chlorella in BG-11 medium (4.97mg/L/day). Mean lipid productivity (50.78% and 39.36%) was highest in BG11 medium for both Botryococcus and Chlorella species, respectively. A sharp decline in sugar content was observed in the late stationary phase of growth from 30th day to 45th day. Fatty acid methyl ester (FAME) profile of the extracted lipids showed predominantly oleic acid, followed by palmitic acid and stearic acid in both the strains when grown in BG-11 medium. The other biodiesel quality parameters were in accordance with the international standards. A complex relationship was found between chemical composition and biodiesel properties. Proximity analysis indicated that the fuel properties of biodiesels are determined by a number of parameters and by the combination of different chemical compositions. The results provide an insight into organic carbon partitioning into lipid compounds and how the organism's lipid metabolism changes due to N-deplete culturing in TAP medium and inorganic carbon source availability as seen in BG-11 and BBM medium.

Role of media composition in biomass and astaxanthin production of Haematococcus pluvialis under two-stage cultivation.

In the present study, the effects of four different culture media on the growth, astaxanthin production and morphology of Haematococcus pluvialis LUGU were studied under two-step cultivation. The interactions between astaxanthin synthesis and secondary messengers, reactive oxygen species (ROS) and mitogen-activated protein kinases (MAPK) were also investigated. In the first green vegetative cell stage, maximal biomass productivity (86.54mgL-1day-1) was obtained in BBM medium. In the induction stage, the highest astaxanthin content (21.5mgg-1) occurred in BG-11 medium, which was higher than in any other media. The expressions of MAPK and astaxanthin biosynthetic genes in BG-11 were higher than in any other media, whereas the ROS content was lower. Biochemical and physiological analyses suggested that the ROS, MAPK and astaxanthin biosynthetic gene expression was involved in astaxanthin biosynthesis in H. pluvialis under different culture media conditions. This study proposes a two-step cultivation strategy to efficiently produce astaxanthin using microalgae.

An innovative mixotrophic approach of distillery spent wash with sewage wastewater for biodegradation and bioelectricity generation using microbial fuel cell

In the present study, H-type microbial fuel cell (H-MFC) has been used to treat distillery spent wash (DSW) diluted with sewage wastewater (SWW) at different mixing ratio. Mixture of DSW and SWW was used as substrate in anaerobic environment. The cathodic compartment was filled with BBM media and microalgae (Scenedesmus abundans). CO2 generated during breakdown of organic substrates by anaerobes present in DSW was utilized by microalga Scenedesmus abundans for photosynthesis. A consortium of two bacteria (Pseudomonas aeruginosa and Bacillus cereus) was used for the 21 days period of DSW treatment. Significant reduction in chemical oxygen demand (COD) in the order of 66% to 78.66% was observed. At 50:50 ratio of DSW and SWW, total dissolved solid (TDS) of 39.66% and total suspended solid (TSS) of 97% were removed. A maximum power density (PD) of 836.81 mW/m2 and open circuit voltage (OCV) of 745.13 mV were obtained along with biomass yield of 0.74 g/L d−1 with above ratio of DSW and SWW. This study demonstrated that proper dilution of Distillery spent wash with sewage wastewater may leads to an efficient wastewater remediation and energy production.

KERAGAMAN DAN KARAKTERISASI MIKROALGA DARI SUMBER AIR PANAS CIWALINI YANG BERPOTENSI SEBAGAI SUMBER BIODISEL

The objectives of the research were to obtain specific microalgae that are able to produce high lipid, and to determine suitable culture technique for optimum growth and maximum lipid production. Microalgae were identified, isolated, selected and then grown on IMK medium at 27-29oC under continuous light irradiation for 24 hours. The microalgae were then selected for lipid content using Nile Red. The selected microalgae were then grown under the same medium and condition as before followed by selection based on their growth rate. To find an appropriate medium for specific microalgae, the selected microalgae were then grown on various media such as BG11, Zarrouk, MBM, PHM and BBM media. When a medium was selected, it was then used as the medium for the nitrogen source and light intensity experiments. Those selected microalgae from each location were cultured on the selected medium at different nitrogen concentration (0,5, 1 and 2 M) and different light intensities (35, 70 and 140 µmol photon/m2/sec). The result showed that Ciwalini has diversity index (H) 2,21. Identification indicated that ciwalini species was Chlorophyta. In this research maximum growth rate was at 2 M nitrogen consentratiom with 140 µmol photon/m2/sec light intensity. Lipid content ranged from 11,7% - 28%. The highest lipid content was occurred on media 0,5 M nitrogen consentration and 140 µmol photon/m2/sec light intensity. Lipid Productivity ranged from 0,070,18 g/l/day.

Differential Expression of Acetyl-CoA Carboxylase (Accase) Gene in Chlorella Ellipsoidea under Nitrogen Replete and Deplete Condition Along with Growth, Lipid and Fatty Acid Profile

The present study aims at exploring the role of nitrogen on growth, lipid and fatty acid content and profile and corresponding differential Acetyl-CoA carboxylase (ACCase) gene expression in Chlorella ellipsoidea in BBM media. Chlorella ellipsoidea is a single-celled oleaginous microalgae and also a nutritious food with high protein content. C. ellipsoidea is a high quality biomass for producing algal oil. The growth of C. ellipsoidea was affected by N+ condition (maximum OD: 0.1929; maximum cell density: 6820 x105 ) and N- condition (maximum OD: 0.1284; maximum cell density: 1733x105 ). The lipid productivity of C. ellipsoidea under nitrogen repletion (N+) condition was 12% on dry weight basis while under nitrogen deplete condition (N- ) it was 17% on 23rd day of harvesting. C16 and C18 fatty acids comprised major components in both N+ and N- conditions. The main components were palmitic acid (C16:0), oleic acid (C18:1), stearic acid (C18:0) and linoleic acid (C18:2) in cultures grown under N+ condition and in N-condition the main components were palmitic acid (C16:0), oleic acid (C18:1) and linoleic acid (C18:2). However, stearic acid (C18:0) showed a sharp decline in case of cultures grown under Ncondition as compared to N+ condition. Moreover, α-linolenic acid (18:3) showed a sharp increase from 20.3% to 32.6% in N+ to N- cultures. Quantitative real time PCR (qRT-PCR) analysis of ACCase gene from nitrogen repletion (N+) and nitrogen depletion (N- ) conditions showed 0.6322 fold up regulation of ACCase gene in N- cultures of C. ellipsoidea cultures as compared to N+ cultures. The growth rate was more in nitrogen repletion condition as compared to nitrogen depletion. However, the lipid percentage was more in Nitrogen depletion condition than in repletion condition. Fatty acid methyl esters (FAME) analysis showed that the main components were C16 and C18 fatty acids in cultures grown under both the conditions, which are considered suitable for biodiesel production.

Kinetic Model of Photoautotrophic Growth of Chlorella sp. Microalga, Isolated from the Setúbal Lagoon.

In this work, a kinetic expression relating light availability in the culture medium with the rate of microalgal growth is obtained. This expression, which is valid for low illumination conditions, was derived from the reactions that take part in the light-dependent stage of photosynthesis. The kinetic expression obtained is a function of the biomass concentration in the culture, as well as of the local volumetric rate of absorption of photons, and only includes two adjustable parameters. To determine the value of these parameters and to test the validity of the hypotheses made, autotrophic cultures of the Chlorella sp. strain were carried out in a modified BBM medium at three CO2 concentrations in the gas stream, namely 0.034%, 0.34% and 3.4%. Moreover, the local volumetric rate of photon absorption was predicted based on a physical model of the interaction of the radiant energy with the suspended biomass, together with a Monte Carlo simulation algorithm. The proposed intrinsic expression of the biomass growth rate, together with the Monte Carlo radiation field simulator, are key to scale up photobioreactors when operating under low irradiation conditions, independently of the configuration of the reactor and of its light source.

Exploring the diversity of microalgal physiology for applications in wastewater treatment and biofuel production

A recently established strain collection of freshwater microalgae native to Quebec was examined for physiological diversity. The 100 strains appeared very heterogeneous in terms of growth when they were cultured at 10±2°C or 22±2°C on the secondary effluent from a municipal wastewater treatment plant (WW) and defined BBM medium. Scatterplots were used to examine the diversity in physiology that might be present in the collection. These showed a number of interesting results. There was a fair amount of dispersion in growth rates by media type independent of temperature. Surprisingly considering that all the isolates had been initially enriched on BBM, the distribution was quite symmetrical around the iso-growth line, suggesting that enrichment on BBM did not seem to bias the cells for growth on this medium versus WW. As well, considering that all the isolates had been initially enriched at 22°C, it is quite surprising that the distribution of specific growth rates was quite symmetrical around the iso-growth line with roughly equal numbers of isolates found on either side. Thus enrichment at 22°C does not seem to bias the cells for growth at this temperature versus 10°C. The scatterplots obtained when the percentage lipid of cultures grown on BBM were compared with cultures grown on WW at either 10°C or 22°C made it apparent that lipid production was favored by growth on WW at either temperature and that lipid production does not seem to be particularly favored by one temperature over the other. When the collection was queried for differences with respect to sampling location, statistical analysis showed that roughly the same degree of physiological diversity was found with samples from the two different aggregate locations.

Fresh water green microalga Scenedesmus abundans: A potential feedstock for high quality biodiesel production

Present investigation studied the potential of fresh water green microalga Scenedesmus abundans as a feedstock for biodiesel production. To study the biomass and lipid yield, the culture was grown in BBM, Modified CHU-13 and BG-11 medium. Among the tested nitrogen concentration using Modified CHU-13 medium, the highest biomass and lipid yield of 1.113±0.05g/L and 489±23mg/L respectively was found in the culture medium with 0.32g/L of nitrogen (KNO3). Different lipid extraction as well as transesterification methods were also tested. Fatty acid profile of alga grown in large scale indigenous made photobioreactor has shown abundance of fatty acids with carbon chain length of C16 and C18. Various biodiesel properties such as cetane number, iodine value and saponification value were found to be in accordance with Brazilian National Petroleum Agency (ANP255) and European biodiesel standard EN14214 which makes S. abundans as a potential feedstock for biodiesel production.

The feasibility of biodiesel production by microalgae using industrial wastewater

This study investigated nitrogen and phosphorus assimilation and lipid production of microalgae in industrial wastewater. Two native strains of freshwater microalgae were evaluated their biomass growth and lipid production in modified BBM medium. Chlamydomonas sp. TAI-2 had better biomass growth and higher lipid production than Desmodesmus sp.TAI-1. The optimal growth and lipid accumulation of Chlamydomonas sp. TAI-2 were tested under different nitrogen sources, nitrogen and CO2 concentrations and illumination period in modified BBM medium. The optimal CO2 aeration was 5% for Chlamydomonas sp. TAI-2 to achieve maximal lipid accumulation under continuous illumination. Using industrial wastewater as the medium, Chlamydomonas sp. TAI-2 could remove 100% NH4+-N (38.4mg/L) and NO3−-N (3.1mg/L) and 33% PO43−-P (44.7mg/L) and accumulate the lipid up to 18.4%. Over 90% of total fatty acids were 14:0, 16:0, 16:1, 18:1, and 18:3 fatty acids, which could be utilized for biodiesel production.

Ettlia oleoabundans growth and oil production on agricultural anaerobic waste effluents

The feasibility of growth and oil production by Ettlia oleoabundans fed with anaerobic digester effluents of three agriculture wastes from the Arkansas Delta, catfish processing waste, soybean field waste, and rice hulls, was studied. Compared to standard BBM medium, all three effluents were deficient in phosphate and nitrate, but rich in ammonia and urea. Best growth was on 2% (v/v) soy effluent, but scant oil was produced on any of the effluents. When the three effluents were mixed, growth did not substantially increase, but oil content increased up to sixfold, depending on age of the effluent. Similar to growth in BBM, the main fatty acids produced were palmitic, oleic, and linoleic. These results show that anaerobically digested agricultural wastes can potentially support both growth and high oil productivity in E. oleoabundans.

Biodegradation of Phenanthrene by the Green AlgaScenedesmus obliquus ES-55

While the degradation of polycyclic aromatic hydrocarbons by bacteria and fungi has been broadly investigated, less is known about the metabolism of these compounds by algae. The goal of the experiments was to test the degradability of phenanthrene by the green alga Scenedesmus obliquus ES-55 (Chlorophyceae) and to identify the metabolites. It was shown that S. obliquus ES-55 metabolized phenanthrene. Under light conditions, phenanthrene (14 mg/L) inhibits cell division by more than twice. However, the metabolic processes in the cells affected by phenanthrene continued because the content of chlorophyll increased. In the exponential phase under phototrophic conditions the alga degraded phenanthrene. Phenanthrene was removed by algae up to 42 % in BBM medium and up to 24 % in Kuhl medium. Dihydroxy-dihydro-phenanthrene, a degradation metabolite in fungi, bacteria and cyanobacteria, could also be detected as a transformation product of S. obliquus ES-55. Further detected common metabolites foster the assumption that both phototrophic and non-photothrophic organisms metabolize phenanthrene via a similar pathway. The present study is the first evidence of the ability of an axenic culture of the green alga S. obliquus to biotransform phenanthrene into other metabolites.

Activities of superoxide dismutase (SOD) isoforms during growth of Scenedesmus (chlorophyta) species and strains grown in batch-cultures

Growth of Scenedesmus species and strains, grown for 28 days in mineral BBM medium in batch-cultures, displayed sigmoidal kinetics that comprised a lag, exponential and declining growth phases. Total SOD activity in these autotrophically cultured organisms, which oscillated within 0.6 – 1.4 Umg protein−1, was rather species-specific and only to some extent depended on the growth phase. Contrary, three S. obliquus strains: wild type 276-6, mutant with blocked PS I (strain 56.80) and mutant with blocked PS II (strain 57.80), cultured for 7 days on BBM medium supplemented with bacto-tryptone and yeast extract (BBM+) turned out to be time-dependent and to have several times higher total SOD activity than one obtained for Scenedesmus grown autotrophically. Regardless of the media composition, the phase of growth and studied organism, dominant isoforms of total SOD were together determined Fe- and Mn-SOD.

Influence of environmental and nutritional factors in the production of astaxanthin from Haematococcus pluvialis

Astaxanthin extracted from green algae is desirable in the food and pharmaceutical industries due to its antioxidant properties. The green unicellular clear water microalga Haematococcus pluvialis has a high production rate of astaxanthin; indeed, it contains more than 80% astaxanthin content in its cells. This remarkable astaxanthin production is commonly obtained under stress conditions such as nutrient deficiency (N or P), high NaCl concentrations, variations of temperature, and other factors. In this vein, a great research effort has been oriented to determine optimal conditions for astaxanthin production by H. pluvialis.The objective of the present study was the analysis of environmental factors, such as light intensity, aeration and nutrients on the growth and astaxanthin production of H. pluvialis. Maximum growth of H. pluvialis obtained was 3.5×105 cells/ml in BBM medium at 28 °C under continuous illumination (177 μmol photon m−2s−1) of white fluorescent light, with continuous aeration (1.5 v.v.m.). Meanwhile, maximal astaxanthin production was 98 mg/g biomass in BAR medium with continuous illumination (345 μmol photon m−2s−1), with 1 g/l of sodium acetate and without aeration.

<i>Pediastrum</i> in Lake Sediment and Its Mineralization

A lot of algae fossils were found in Cenozoic lake sediments, especially Pediastrum fossil sedimentary deposits in some places of China and also in some nearby seacoasts. For imitating Pediastrum mine ralization in lake sediments, several species of Pediastrum are cultured using BBM medium and sea water with 18% salt. By optical and electronic microscope observation and photosyntheic pigment analysis, we found that Pediastrum boryanum, P.duplex var clathratum and P.tetras , etc. cannot grow well in sea water. If cultured in saline medium, the specimen will die in a short period of time. We consider that probably the Pediastrum fossil that appeared in marine sediments were transported to the sea by river. In order to prove the mineralization condition of in living organism and fossils of Pediastrum, the following analysis is made. The fat soluble substances are high and they contain a small amount of alkane, alkene fatty acid and a great deal of plant pigments. Pediastrum has high H/C and low O/C (atom number ratio) value. Therefore, it is a good resource of oil formation. The products of oxidative degradation of the insoluble cell wall of Pediastrum are similar to the production obtained by kerogen, which is known to be of algal origin. So, the insolable materials of cell wall are probably a source of kerogen during the deposition.

The effects of crude and fuel oils on the growth, chlorophyll 'a' content and dry matter production of a green alga Scenedesmus quadricauda (Turp.) bréb.

The growth of Scenedesmus quadricauda algae in a batch culture was examined in the presence of crude oil and fuel oil, added to the cultivation medium in the form of a water-soluble fraction (WSF), water extract (WE) and oil-water dispersion (OWD). On applying various concentrations of oils, a decrease in the number of cells, dry matter and chlorophyll 'a' production, with respect to the cell population, was observed. The extent of this decrease depended on the kind and concentration of the soluble and dispersed hydrocarbon fractions and on the proportions in which these occurred in the culture medium. On the other hand, the water extracts of both oils stimulated dry mass and chlorophyll 'a' content with respect to a single cell. This effect was accompanied by increased size of the algal cells. The WSF, WE and OWD of fuel oil, prepared from 200, 50 and 1 cm(3) of oil per dm(3) of BBM medium, respectively, had a similar inhibitory effect, which points to the dominant role of oil dispersion in the reduction of algal growth. Chemical analysis of the water extracts of fuel oil revealed the presence of 35 hydrocarbons of various kinds, mainly n-alkanes and polycyclic aromatic hydrocarbons.

A NEW HOMOTHALLIC VARIETY OF CHLAMYDOMONAS MOEWUSH (CHLOROPHYCEAE)1

SUMMARYA new homothallic variety of Chlamydomonas moewusii Gerloff var. monoica is described. When first isolated, the alga exhibited a very strong mating reaction (80–90% zygotes on 2 wk BBM agar slants), but after 2 mo in axenic culture, the reaction was significantly reduced in intensity. Attempts were made to restore the initial mating intensity by varying environmental conditions, but met with limited success. The alga did not grow heterotrophically in carbon‐supplemented BBM medium.