Podcast
Questions and Answers
Which contaminant is not a type of algae?
Which contaminant is not a type of algae?
Maintaining a pH above 10 is beneficial for managing green algae.
Maintaining a pH above 10 is beneficial for managing green algae.
True
What is a method used to manage aquatic insects in algae cultures?
What is a method used to manage aquatic insects in algae cultures?
Nettin in situ or preharvest screening
To avoid unexpected nutrient deficiencies, regular tests on __________ concentration should be conducted.
To avoid unexpected nutrient deficiencies, regular tests on __________ concentration should be conducted.
Signup and view all the answers
Match the type of organism to its corresponding management method.
Match the type of organism to its corresponding management method.
Signup and view all the answers
What is the primary goal of culture monitoring?
What is the primary goal of culture monitoring?
Signup and view all the answers
Regular microscopic examination does not include checking for contaminating organisms.
Regular microscopic examination does not include checking for contaminating organisms.
Signup and view all the answers
What is one benefit of using pulse amplitude modulated fluorometry (PAM)?
What is one benefit of using pulse amplitude modulated fluorometry (PAM)?
Signup and view all the answers
High salinity is important for managing __________ species of Dunaliella.
High salinity is important for managing __________ species of Dunaliella.
Signup and view all the answers
Match the contaminant to its management strategy.
Match the contaminant to its management strategy.
Signup and view all the answers
What is a disadvantage of excavated ponds?
What is a disadvantage of excavated ponds?
Signup and view all the answers
Above ground concrete ponds are expensive.
Above ground concrete ponds are expensive.
Signup and view all the answers
What is a characteristic of excavated ponds?
What is a characteristic of excavated ponds?
Signup and view all the answers
PVC ponds may contain _______________ as plasticizing agents.
PVC ponds may contain _______________ as plasticizing agents.
Signup and view all the answers
What is an advantage of CPE ponds?
What is an advantage of CPE ponds?
Signup and view all the answers
Carbonator increases algae growth.
Carbonator increases algae growth.
Signup and view all the answers
Match the type of pond with its construction factor:
Match the type of pond with its construction factor:
Signup and view all the answers
Above ground concrete ponds are suitable for _______________ algae.
Above ground concrete ponds are suitable for _______________ algae.
Signup and view all the answers
What is a disadvantage of PVC ponds?
What is a disadvantage of PVC ponds?
Signup and view all the answers
What is a characteristic of Above ground concrete ponds?
What is a characteristic of Above ground concrete ponds?
Signup and view all the answers
What is a major challenge during the scale-up of Spirulina sp. cultures?
What is a major challenge during the scale-up of Spirulina sp. cultures?
Signup and view all the answers
Chlorella can be used to derive inoculum from existing culture ponds.
Chlorella can be used to derive inoculum from existing culture ponds.
Signup and view all the answers
What percentage of the total production costs do nutrients account for?
What percentage of the total production costs do nutrients account for?
Signup and view all the answers
The production of Spirulina from flask cultures to raceway ponds can take at least _____ weeks.
The production of Spirulina from flask cultures to raceway ponds can take at least _____ weeks.
Signup and view all the answers
Match the algae species with their respective characteristics concerning inoculum sourcing:
Match the algae species with their respective characteristics concerning inoculum sourcing:
Signup and view all the answers
Which type of medium is typically used for health food applications?
Which type of medium is typically used for health food applications?
Signup and view all the answers
Why is culturing microalgae in outdoor ponds a preferred method?
Why is culturing microalgae in outdoor ponds a preferred method?
Signup and view all the answers
Deep ponds are a type of outdoor pond used for culturing microalgae.
Deep ponds are a type of outdoor pond used for culturing microalgae.
Signup and view all the answers
What are the advantages of using several small ponds for culturing microalgae?
What are the advantages of using several small ponds for culturing microalgae?
Signup and view all the answers
A well-mixed, intensive system can achieve high __________ density.
A well-mixed, intensive system can achieve high __________ density.
Signup and view all the answers
Match the following microalgae species with their suitability for outdoor ponds:
Match the following microalgae species with their suitability for outdoor ponds:
Signup and view all the answers
What is a disadvantage of using a large outdoor pond?
What is a disadvantage of using a large outdoor pond?
Signup and view all the answers
The source and quality of water are important factors to consider when selecting a site for an outdoor pond.
The source and quality of water are important factors to consider when selecting a site for an outdoor pond.
Signup and view all the answers
A natural source of __________ is desirable for outdoor ponds.
A natural source of __________ is desirable for outdoor ponds.
Signup and view all the answers
Why is it important to consider the final product when culturing microalgae in outdoor ponds?
Why is it important to consider the final product when culturing microalgae in outdoor ponds?
Signup and view all the answers
What is an advantage of using raceway ponds?
What is an advantage of using raceway ponds?
Signup and view all the answers
Study Notes
Culturing Microalgae in Outdoor Ponds
- Outdoor ponds are a cost-effective method for culturing microalgae, particularly in tropical climates.
- Suitable microalgae species for outdoor pond culture include Spirulina platensis, Chlorella vulgaris, Haematococcus pluvialis, Dunaliela salina, and Phaeodactylum tricornutum.
Pond Design and Construction
- Shallow, unlined, and unmixed ponds are used for microalgae culture.
- Pond size and shape can vary, including circular, raceway, and deep ponds.
- Several small ponds can be used to avoid culture problems and reduce the impact of contamination.
- Pond size and climatic conditions, such as temperature, rainfall, and sunlight, must be considered in pond design.
Pond Mixing
- Turbulent flow is necessary to prevent cell settling and thermal and oxygen stratification.
- Velocities of 5.0 cm/s are sufficient for small ponds, but higher velocities (20-30 cm/s) are required for larger ponds to maintain mixing.
- Paddle wheels can be used to create mixing in raceway cultures.
- Higher energy inputs are required for more intense mixing, increasing operational costs.
Relationship between Pond Mixing and Depth
- Algae require light, and high cell density can lead to light absorption in the upper layers of the pond.
- Shallow ponds are desirable for uniform light intensity, but may not be suitable for all species.
- A balance between optimizing culture depth for photosynthetic efficiency and enhancing mixing/turbulence is necessary for maximum productivity.
Pond Construction Materials
- Excavated ponds are cheap but have sloping walls that can lead to contamination.
- Above-ground concrete ponds are expensive but provide a constant depth.
- PVC linings can inhibit algae growth and may contain harmful chemicals.
- CPE linings do not inhibit algae growth but may not be approved for food use in some countries.
Strain Selection
- Microalgae strains should be selected based on their biochemical composition, temperature tolerance, and resistance to mechanical and physiological stress.
Scale-Up
- Scale-up of microalgae cultures involves diluting the inoculum through successive volumes up to the production pond.
- Two methods for scale-up include using small laboratory flask cultures and deriving the inoculum from existing culture ponds.
- Spirulina and Dunaliela can be scaled up using existing culture ponds, while Chlorella and Haematococcus require axenic cultures.
Culture Medium
- Culture medium should be designed to meet the specific requirements of the microalgae species being cultured.
- Cost of nutrients can account for 10-30% of total production costs.
- Recycling medium with remaining nutrients can reduce environmental problems and costs.
Pond Management
- Control and management of contaminants, such as bacteria, viruses, fungi, other algae, zooplankton, insects, and airborne material, is essential.
- Operating the culture system as a batch culture, restarting with fresh inoculum, and providing conditions favorable to the desired species can help manage contaminants.
Contaminant Management
- Contaminants can include green algae, non-carotenogenic species, unicellular green algae, aquatic insects, brine shrimps, and amoeba.
- Management strategies include maintaining specific conditions, such as pH and salinity, and using methods like netting, screening, and ammonia treatment to control contaminants.
Culture Monitoring
- Regular microscopic examination can detect abnormal morphological changes and contaminating organisms.
- Routine testing of nutrient concentrations and monitoring pH and oxygen levels can provide an early warning system for nutrient deficiencies or other issues.
- Pulse amplitude modulated fluorometry (PAM) can determine the physiological state of the algae.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz covers the basics of culturing microalgae in outdoor ponds, including the advantages and disadvantages of different pond types and algae species. Learn about the benefits and challenges of outdoor microalgae cultivation.
