scholarly journals A Recommendation for a Pre-Standardized Marine Microalgal Dry Weight Determination Protocol for Laboratory Scale Culture Using Ammonium Formate as a Washing Agent

Biology ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 799
Author(s):  
Yam Sim Khaw ◽  
Hui Teng Tan ◽  
Arissara Sopawong ◽  
Noor Azmi Shaharuddin ◽  
Abdul Rahman Omar ◽  
...  
Keyword(s):  
Dry Weight ◽  
Comparative Assessment ◽  
Laboratory Scale ◽  
Ammonium Formate ◽  
Critical Parameters ◽  
Microalgal Biomass ◽  
Standardized Protocol ◽  
Washing Process ◽  
Pretreatment Conditions ◽  
Microalgal Species

Microalgal biomass is one of the crucial criteria in microalgal studies. Many reported methods, even the well-established protocol on microalgal dry weight (DW) determination, vary greatly, and reliable comparative assessment amongst published results could be problematic. This study aimed to determine the best condition of critical parameters in marine microalgal DW determination for laboratory-scale culture using four different marine microalgal species. These parameters included the washing process, grades of glass microfiber filter (GMF), GMF pretreatment conditions, washing agent (ammonium formate) concentrations, culture: washing agent ratios (v:v) and washing cycles. GMF grade GF/A with precombustion at 450 °C provided the most satisfactory DW and the highest ash-free dry weight (AFDW)/DW ratio. Furthermore, 0.05 M ammonium formate with 1:2 culture: washing agent ratio and a minimum of two washing cycles appeared to be the best settings of microalgal DW determination. The present treatment increased the AFDW/DW ratio of the four respective microalgae by a minimum of 19%. The findings of this study could serve as a pivotal reference in developing a standardized protocol of marine microalgal DW determination to obtain veracious and reliable marine microalgal DW.

scholarly journals Isolation, Identification and Biotechnological Applications of a Novel, Robust, Free-living Chlorococcum (Oophila) amblystomatis Strain Isolated from a Local Pond

2020 ◽  
Vol 10 (9) ◽  
pp. 3040
Author(s):  
Nádia Correia ◽  
Hugo Pereira ◽  
Joana T. Silva ◽  
Tamára Santos ◽  
Maria Soares ◽  
...  
Keyword(s):  
Growth Performance ◽  
Protein Content ◽  
Dry Weight ◽  
High Protein ◽  
Rrna Gene ◽  
Scale Production ◽  
Free Living ◽  
Microalgal Biomass ◽  
High Protein Content ◽  
Oophila Amblystomatis

Bioprospection of novel autochthonous strains is key to the successful industrial-scale production of microalgal biomass. A novel Chlorococcum strain was recently isolated from a pond inside the industrial production facility of Allmicroalgae (Leiria, Portugal). Phylogenetic analysis based on 18S ribosomal ribonucleic acid (rRNA) gene sequences suggests that this isolate is a novel, free-living Oophila amblystomatis strain. However, as our phylogenetic data strongly suggests that the aforementioned taxon belongs to the genus Chlorococcum, it is here proposed to rename this species as Chlorococcum amblystomatis. In order to characterize the biotechnological potential of this novel isolate, growth performance and biochemical composition were evaluated from the pilot (2.5-m3) to industrial (10-m3) scale. The highest maximum areal productivity (36.56 g·m−2·day−1) was reached in a 10-m3 tubular photobioreactor (PBR), as compared to that obtained in a 2.5-m3 PBR (26.75 g·m−2·day−1). Chlorococcum amblystomatis displayed high protein content (48%–56% dry weight (DW)) and moderate levels of total lipids (18%–31% DW), carbohydrates (6%–18% DW) and ashes (9%–16% DW). Furthermore, the lipid profile was dominated by polyunsaturated fatty acids (PUFAs). The highest pigment contents were obtained in the 2.5-m3 PBR, where total chlorophylls accounted for 40.24 mg·g−1 DW, followed by lutein with 5.37 mg·g−1 DW. Overall, this free-living Chlorococcum amblystomatis strain shows great potential for nutritional applications, coupling a promising growth performance with a high protein content as well as relevant amounts of PUFAs, chlorophyll, and carotenoids.

Effects of C/N ratio on nitrous oxide production from nitrification in a laboratory-scale biological aerated filter reactor

2016 ◽  
Vol 75 (6) ◽  
pp. 1270-1280 ◽  
Author(s):  
Qiang He ◽  
Yinying Zhu ◽  
Leilei Fan ◽  
Hainan Ai ◽  
Xiaoliu Huangfu ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Wastewater Treatment ◽  
Dna Analysis ◽  
Denaturing Gradient Gel Electrophoresis ◽  
N2o Emission ◽  
Laboratory Scale ◽  
Critical Parameters ◽  
Biological Aerated Filter ◽  
N2o Production ◽  
Aerated Filter

Emission of nitrous oxide (N2O) during biological wastewater treatment is of growing concern. This paper reports findings of the effects of carbon/nitrogen (C/N) ratio on N2O production rates in a laboratory-scale biological aerated filter (BAF) reactor, focusing on the biofilm during nitrification. Polymerase chain reaction–denaturing gradient gel electrophoresis (PCR-DGGE) and microelectrode technology were utilized to evaluate the mechanisms associated with N2O production during wastewater treatment using BAF. Results indicated that the ability of N2O emission in biofilm at C/N ratio of 2 was much stronger than at C/N ratios of 5 and 8. PCR-DGGE analysis showed that the microbial community structures differed completely after the acclimatization at tested C/N ratios (i.e., 2, 5, and 8). Measurements of critical parameters including dissolved oxygen, oxidation reduction potential, NH4+-N, NO3−-N, and NO2−-N also demonstrated that the internal micro-environment of the biofilm benefit N2O production. DNA analysis showed that Proteobacteria comprised the majority of the bacteria, which might mainly result in N2O emission. Based on these results, C/N ratio is one of the parameters that play an important role in the N2O emission from the BAF reactors during nitrification.

scholarly journals An Innovative Low-Cost Equipment for Electro-Concentration of Microalgal Biomass

2020 ◽  
Author(s):  
Edwar M. Sanchez-Galvis ◽  
Ingri Y. Cardenas-Gutierrez ◽  
Jefferson E. Contreras-Ropero ◽  
Janet B. García-Martínez ◽  
Andrés F. Barajas-Solano ◽  
...  
Keyword(s):  
Research And Development ◽  
Low Cost ◽  
Laboratory Scale ◽  
Suitable Method ◽  
Innovative Approach ◽  
Mixing Rate ◽  
Microalgal Biomass ◽  
Biomass Quality ◽  
The World ◽  
Different Parts

Microalgal harvesting is one of the most challenging processes in the development of algal research and development. Several methods, such as centrifugation, flocculation, and filtration, are available at the laboratory scale. However, the requirement of expensive pieces of equipment and the possibility of biomass contamination are recurring gaps that hinder the development of microalgae I+D in different parts of the world. Recently, the electroflotation has been proved as a suitable method for the harvesting of different species of microalgae and cyanobacteria. To this day, there are no companies that sell laboratory-scale electroflotation equipment; this is mainly due to the gap in the knowledge on which factors (time, mixing rate, number of electrodes, and others) will affect the efficiency of concentration without reducing the biomass quality. This paper aims to build an innovative low-cost electroflotation system under 300 USD with cheap and resistant materials. To achieve our goal, we test the interaction of three variables (time, mixing rate, and amount of electrodes) were evaluated. Results showed that an efficiency closer to 100% could be achieved under 20 minutes using >10 electrodes and 150 rpm. We hope this innovative approach can be used by different researchers to improve our knowledge of the concentration and harvesting of algae and cyanobacteria.

scholarly journals Real-Time Monitoring of Microalgal Biomass in Pilot-Scale Photobioreactors Using Nephelometry

Processes ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1530
Author(s):  
Eli S. J. Thoré ◽  
Floris Schoeters ◽  
Jornt Spit ◽  
Sabine Van Miert
Keyword(s):  
Real Time ◽  
Continuous Cultivation ◽  
Dry Weight ◽  
Pilot Scale ◽  
Light Scatter ◽  
Biomass Density ◽  
Porphyridium Purpureum ◽  
Microalgal Biomass ◽  
Non Invasive ◽  
Microalgae Biomass

The increasing cultivation of microalgae in photobioreactors warrants efficient and non-invasive methods to quantify biomass density in real time. Nephelometric turbidity assessment, a method that measures light scatter by particles in suspension, was introduced already several decades ago but was only recently validated as a high-throughput tool to monitor microalgae biomass. The light scatter depends on the density of the suspended particles as well as on their physical properties, but so far there are hardly any accounts on how nephelometric assessment relates to classic methods such as dry weight and spectrophotometric measurement across a broad biomass density range for different microalgae species. Here, we monitored biomass density online and in real time during the semi-continuous cultivation of three commercial microalgae species Chloromonas typhlos, Microchloropsis gaditana and Porphyridium purpureum in pilot-scale photobioreactors, and relate nephelometric turbidity to dry weight and optical density. The results confirm a relatively strong (R2 = 0.87–0.93) and nonlinear relationship between turbidity and biomass density that differs among the three species. Overall, we demonstrate how nephelometry can be used to monitor microalgal biomass in photobioreactors, and provide the necessary means to estimate the biomass density of the studied species from turbidity data to facilitate automated biomass monitoring.

FABRICATION AND EVALUATION OF LABORATORY SCALE MINIGRANULATOR USING THE CONCEPT OF DESIGN OF EXPERIMENTS

INDIAN DRUGS ◽  
2014 ◽  
Vol 51 (08) ◽  
pp. 15-21
Author(s):  
M. C Gohel ◽  
◽  
S. A. Mansuri ◽  
V. T. Thakkar ◽  
L. H. Baldania ◽  
...  
Keyword(s):  
Research And Development ◽  
Laboratory Scale ◽  
The Other ◽  
Critical Parameters ◽  
Wet Granulation ◽  
Granulation Process ◽  
Manual Method ◽  
Box And Behnken Design ◽  
Binder Concentration ◽  
Development Department

The main objective of the present work was to design, fabricate and evaluate a laboratory scale mini granulator for applications in the research and development department. The Box and Behnken design was adopted to identify the critical parameters in the wet granulation process. The granules and tablets were characterized. The spherical granules obtained by using the fabricated mini granulator were of size 600 to 750 μ. On the other hand, the manual method (mortar and pestle) resulted in the formation of larger granules (800-950 μ). Recovery of granules by both the manual method and laboratory scale mini granulator were 71 and 90%, respectively. From the Box and Behnken design, an optimized formula was achieved with granulation time of 10 min, binder concentration 2.35 % and impeller speed 3000 rpm. Use of the mini granulator is recommended for screening of various formulations at R&D centers and also at colleges where the availability of drug is a few grams.

Activated sludge as a possible source of biodegradable plastic

1998 ◽  
Vol 38 (2) ◽  
pp. 103-109 ◽  
Author(s):  
H. Satoh ◽  
Y. Iwamoto ◽  
T. Mino ◽  
T. Matsuo
Keyword(s):  
Activated Sludge ◽  
Dry Weight ◽  
Laboratory Scale ◽  
Biodegradable Plastic ◽  
Anaerobic Conditions ◽  
Aerobic Conditions ◽  
Aerobic Process ◽  
Aerobic Processes ◽  
Anaerobic Zone

Polyhydroxyalkanaote (PHA) is known to be temporarily stored by microorganisms in activated sludge especially in the anaerobic-aerobic processes. When PHA is extracted from activated sludge, it is a thermoplastic with the remarkable characteristics of biodegradability. We investigated the possibility of using activated sludge for the production of PHA, focusing on increasing the PHA content of activated sludge. Activated sludge from laboratory scale anaerobic-aerobic reactors accumulated PHA of around 20% under anaerobic conditions and up to 33% under aerobic conditions. In order to further increase the PHA content of activated sludge, we introduced the “microaerophilic-aerobic” process, where a limited amount of oxygen is supplied into the anaerobic zone of the anaerobic-aerobic process. Activated sludge acclimatized in the microaerophilic-aerobic process accumulated PHA of as much as 62% of sludge dry weight. The “microaerophilic-aerobic” process was demonstrated to be an effective process for the enrichment of PHA-accumulating microorganisms.

scholarly journals Extraction of Astaxanthin and Lutein from Microalga Haematococcus pluvialis in the Red Phase Using CO2 Supercritical Fluid Extraction Technology with Ethanol as Co-Solvent

Marine Drugs ◽  
2018 ◽  
Vol 16 (11) ◽  
pp. 432 ◽  
Author(s):  
Antonio Molino ◽  
Sanjeet Mehariya ◽  
Angela Iovine ◽  
Vincenzo Larocca ◽  
Giuseppe Di Sanzo ◽  
...  
Keyword(s):  
Supercritical Fluid Extraction ◽  
Supercritical Fluid ◽  
Haematococcus Pluvialis ◽  
Dry Weight ◽  
Fluid Extraction ◽  
Extraction Technology ◽  
Experimental Activity ◽  
Extracting Solvent ◽  
Scale Reactor ◽  
Microalgal Species

Astaxanthin and lutein, antioxidants used in nutraceutics and cosmetics, can be extracted from several microalgal species. In this work, investigations on astaxanthin and lutein extraction from Haematococcus pluvialis (H. pluvialis) in the red phase were carried out by means of the supercritical fluid extraction (SFE) technique, in which CO2 supercritical fluid was used as the extracting solvent with ethanol as the co-solvent. The experimental activity was performed using a bench-scale reactor in semi-batch configuration with varying extraction times (20, 40, 60, and 80 min), temperatures (50, 65, and 80 °C) and pressures (100, 400, and 550 bar). Moreover, the performance of CO2 SFE with ethanol was compared to that without ethanol. The results show that the highest astaxanthin and lutein recoveries were found at 65 °C and 550 bar, with ~18.5 mg/g dry weight (~92%) astaxanthin and ~7.15 mg/g dry weight (~93%) lutein. The highest astaxanthin purity and the highest lutein purity were found at 80 °C and 400 bar, and at 65 °C and 550 bar, respectively.

scholarly journals Bioflocculation of Euglena gracilis via direct application of fungal filaments: a rapid harvesting method

2021 ◽  
Author(s):  
Danielle Bansfield ◽  
Kristian Spilling ◽  
Anna Mikola ◽  
Jonna Piiparinen
Keyword(s):  
Euglena Gracilis ◽  
Low Cost ◽  
Dry Weight ◽  
Fungal Species ◽  
Cell Integrity ◽  
Microalgal Biomass ◽  
Cell Counts ◽  
Penicillium Restrictum ◽  
Harvesting Method ◽  
Ca 50

AbstractThe high cost and environmental impact of traditional microalgal harvesting methods limit commercialization of microalgal biomass. Fungal bioflocculation of microalgae is a promising low-cost, eco-friendly method but the range of fungal and microalgal species tested to date is narrow. Here, eight non-pathogenic, filamentous fungi were screened for their ability to self-pelletize and flocculate Euglena gracilis (ca.50 µm motile microalga) in suspension. Self-pelletization was tested under various rotational speeds, and species which formed pellets (Ø > 0.5 cm) were selected for harvesting tests. Filaments of each species were combined with E. gracilis at various ratios based on dry weight. Harvesting efficiency was determined by measuring the change in cell counts over time, and settling of the flocs was evaluated by batch settling tests. Three fungal species, Ganoderma lucidum, Pleurotus ostreatus, and Penicillium restrictum, were able to reliably flocculate and harvest 62–75% of the microalgae while leaving it unharmed. The results demonstrated that self-pelletization, harvesting, and settling were dependent on the fungal species. The fungi to algae ratio also had significant but contrasting effects on harvesting and settling. In balancing the needs to both harvest and settle the biomass, the optimal fungi to algae ratio was 1:2. The application of fungal filaments to microalgae in suspension produced readily settling flocs and was less time-consuming than other commonly used methods. This method is especially attractive for harvesting microalgal biomass for low-value products where speed, low cost, and cell integrity is vital.

scholarly journals EFFECTS OF DEPTH AND CONCENTRATION OF DIGESTATE ON GROWTH OF THREE MICROALGAL SPECIES

2016 ◽  
Vol 54 (5) ◽  
pp. 591 ◽  
Author(s):  
Nguyen Tran Thien Khanh
Keyword(s):  
Specific Growth ◽  
Low Cost ◽  
Middle Layer ◽  
Bottom Layer ◽  
Cell Number ◽  
Continuous Illumination ◽  
Microalgal Biomass ◽  
Specific Growth Rates ◽  
Counting Cell ◽  
Microalgal Species

In order to design a culture system for microalgal biomass production with a low cost and convenient cell collection, growth performance of mixtures of microalgal cells, including Euglena gracilis, Chlorella vulgaris, and Dunaliella tertiolecta cultured in a volume of 1 L were investigated at a PPFD of 300 µmol m-2 s-1 at the surface of the solution with continuous illumination at 30 °C. Each culture container contained diluted digestate at concentrations of 5, 10, 15, 20, and 50 %. Sample cells for counting cell number were collected daily at three depths: 0–50 mm (the surface layer), 10–15 mm (the middle layer), and 25–30 mm (the bottom layer). Pseudo-specific growth rates (ms) of each species at each depth were calculated as cellular multiplication rates using number of cells per time. In each layer, the average ms of each species was highest in 5 % digestate. The average ms of all three microalgal species (0.035 h-1) was observed in all layers in 5 % digestate solution. The ms of each species was highest in the bottom layer in 5% digestate (0.048 h-1, 0.041 h-1, and 0.022 h-1, respectively for C. vulgaris, E. gracilis, and D. tertiolecta). In conclusion, E. gracilis, C. vulgaris, and D. tertiolecta showed the highest specific growth rate in 5 % digestate in all layer.

Sign in / Sign up

Export Citation Format

Share Document