Handbook of Marine Microalgae

Biotechnology Advances

Se-Kwon Kim

• Publisher: Academic Press
• Year: 2015
• Print ISBN: 9780128007761
• eBook ISBN: 9780128011249
• Topic: Biological Sciences
• Subtopic: Marine Biology
• Index: Biological Sciences

Handbook of Microalgae: Biotechnology Advances offers complete coverage of marine microalgae, including biology, production techniques, biotechnological applications, economic perspectives of applications, and environmental effects of marine microalgae blooms. With contributions from world experts, Handbook of Microalgae: Biotechnology Advances focuses on microalgae from an organism perspective to offer a complete picture from evolution to biofuel. - Focuses on a comprehensive approach from an organism point of view - Contains full coverage of all aspects of microalgae from biology through biotechnological and biomedical applications - Includes biological properties of commercial algal species - Provides microalgae screening and identification methods, culturing methods and new aspects of processing

Chapter 1

Marine Microalgae Biotechnology

Present Trends and Future Advances

Jayachandran Venkatesan, Panchanathan Manivasagan, and Se-Kwon Kim Pukyong National University, Department of Marine-Bio Convergence Science and Marine Bioprocess Research Center, Busan, South Korea

Abstract

In recent years, considerable interest has been paid to marine microalgae research in the fields of nutraceuticals, pharmaceuticals, cosmeceuticals, and production of biofuels. This chapter gives a brief overview of this book's content. We discuss isolation, culture techniques, collection, and open pond and photobioreactor systems of growing microalgae. In addition, fatty acid, biological, and biomedical applications of marine microalgae are explored. Biofuels such as bioethanol, biohydrogen, and biodiesel are also briefly discussed.

Keywords

Biofuels; Marine microalgae; Nutraceuticals; Open pond; Pharmaceuticals; Photobioreactor

1. Introduction

Microalgae are unicellular species, commonly found in marine and freshwater with the size ranging from a few micrometers to a few hundreds of micrometers. It has been estimated that 2 × 10⁵ to 8 × 10⁵ species exist. Microalgae are a promising source for several bioactive compounds (Cardozo et al., 2007; Norton et al., 1996). Polymers, peptides, fatty acids, carotenoids, toxins, and sterols are important bioactive products produced by microalgae. Microalgae do not contain stems and roots as do higher plants. The three most important classes of microalgae in terms of abundance are the diatoms (Bacillariophyceae), the green algae (Chlorophyceae), and the golden algae (Chrysophyceae). The cyanobacteria or blue-green algae (Cyanophyceae) are also referred to as microalgae, i.e., Spirulina (Arthrospira platensis and Arthrospira maxima).

2. Isolation and Culture

Isolation, production, and culture of microalgae are important steps to producing a commercial product in sufficient amounts. Microalgae growths are dependent on light, water temperature, nutrient concentration, salinity, and pH (Brennan and Owende, 2010; Mutanda et al., 2011). Collection, sampling, and preservation techniques must be optimized to grow a high-quality microalgae sample. Three important isolation techniques are commonly used for microalgae collection:

1. Streaking

2. Serial dilution

3. Single-cell isolation (He et al., 2012).

Different kinds of culture techniques are available to culture microalgae; culture media and culture conditions are the main aspects to be considered in microalgae cultivation. Several important nutrients (nitrate, urea, ammonium, vitamins, phosphorous, nitrogen, iron, manganese, selenium, cobalt, nickel, and zinc) are required for the production of any microalgae species (Andersen, 2005; Harrison and Berges, 2005).

Microalgae can be cultured mainly in two different kinds of systems:

1. Open cultivation

2. Photobioreactor.

The traditional open cultivation method (lakes and ponds) has been used since 1950. The photobioreactor system has more advantages than open cultivation, avoiding several issues such as contamination and environmental disturbance. There are three distinct algae production mechanisms: photoautotrophic, heterotrophic, and mixotrophic.

3. Applications of Marine Microalgae

Microalgae have been widely used for various applications including human and animal nutrition, cosmetics, pharmaceuticals, CO₂ capture, bioenergy production, and nutrient removal from wastewater. Biological properties of algae and their components are well studied in the following areas of research: antioxidants, antimicrobials, anticancer agents, anti-inflammatory and cardiovascular health, anti-obesity, and antidiabetic activity (Dominguez, 2013).

3.1. Animal Feed

Microalgae have been investigated as human and animal foods for over six decades (Liu et al., 2014). Although several hundreds of microalgae species have been investigated for food applications, only a few have been used in aquaculture. The most common species are Chlorella, Tetraselmis, Isochrysis, Pavlova, Phaeodactylum, Chaetoceros, Nannochloropsis, Skeletonema, and Thalassiosira genera (Brown et al., 1996; Spolaore et al., 2006). Marine algae have been used as food additives, for bivalve mollusks (oysters, scallops, clams, and mussels) and fishmeal. There is a promising work in the area of using microalgae as a food additive to increase weight, oil content, and protein deposition in muscle. The nutritional composition of microalgae is made up of carbohydrates, proteins, vitamins, lipids, antioxidants, and other trace elements. Kang et al. (2012) reported the nutritional composition of microalgae (Navicular incerta): crude lipids–8.76%, crude proteins–50.38%, and carbohydrates–10.84%, respectively. A general overview of microalgae in food usage is explained in Figure 1.

3.2. Fatty Acids

Microalgae are traditionally considered good sources of fatty acids (Benemann, 1989; Borowitzka, 2013). The accumulation of fatty acids by microalgae is well developed and presented elsewhere (Griffiths and Harrison, 2009; Rodolfi et al., 2009). The presence of eicosapen...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Contributors
• Preface
• Acknowledgments
• Chapter 1. Marine Microalgae Biotechnology: Present Trends and Future Advances
• Chapter 2. An Introduction to Microalgae: Diversity and Significance
• Chapter 3. Microalgal Classification: Major Classes and Genera of Commercial Microalgal Species
• Chapter 4. Microalgae Isolation and Basic Culturing Techniques
• Chapter 5. Mass Production of Microalgae
• Chapter 6. Microalgal Biotechnology: The Way Forward
• Chapter 7. Stability of Valuable Components during Wet and Dry Storage
• Chapter 8. Application of Microalgae Protein to Aquafeed
• Chapter 9. From the Ancient Tribes to Modern Societies, Microalgae Evolution from a Simple Food to an Alternative Fuel Source
• Chapter 10. Biofuel Production from Microalgae
• Chapter 11. Biohydrogen from Microalgae, Uniting Energy, Life, and Green Future
• Chapter 12. Bioethanol Production from Microalgae
• Chapter 13. Medicinal Effects of Microalgae-Derived Fatty Acids
• Chapter 14. Innovative Microalgae Pigments as Functional Ingredients in Nutrition
• Chapter 15. Application of Diatom Biosilica in Drug Delivery
• Chapter 16. Microalgal Nutraceuticals
• Chapter 17. Microalgae as a Novel Source of Antioxidants for Nutritional Applications
• Chapter 18. Production of Biopharmaceuticals in Microalgae
• Chapter 19. Nutritional and Pharmaceutical Properties of Microalgal Spirulina
• Chapter 20. Applications of Microalgae-Derived Active Ingredients as Cosmeceuticals
• Chapter 21. Supercritical Fluid Extraction of Microalgae (Chlorella vulagaris) Biomass
• Chapter 22. Exploiting the Molecular Genetics of Microalgae: From Strain Development Pipelines to the Uncharted Waters of Mass Production
• Chapter 23. Microalgal Systems Biology Through Genome-Scale Metabolic Reconstructions for Industrial Applications
• Chapter 24. Genetic Engineering of Marine Microalgae to Optimize Bioenergy Production
• Chapter 25. Genetic Optimization of Microalgae for Biohydrogen Production
• Chapter 26. Genetic Engineering of Microalgae for Production of Value-added Ingredients
• Chapter 27. Genetic Engineering of Microalgae for Production of Therapeutic Proteins
• Chapter 28. An Expressed Sequence Tag Database Analysis of Fatty Acid Genes in Stichococcus bacillaris Strain Siva2011
• Chapter 29. Microalgae-based Wastewater Treatment
• Chapter 30. Bioremediation of Heavy Metals by Microalgae
• Chapter 31. Bioremediation with Microalgae: Toward Sustainable Production of Biofuels
• Chapter 32. Phycoremediation-Coupled Biomethanation of Microalgal Biomass
• Chapter 33. N2-Fixing Cyanobacteria: Ecology and Biotechnological Applications
• Chapter 34. An Overview of Harmful Algal Blooms on Marine Organisms
• Chapter 35. Microalgae-Derived Toxic Compounds
• Chapter 36. Toxicity Bioassays on Benthic Diatoms
• Chapter 37. Ciguatera: Tropical Reef Fish Poisoning
• Chapter 38. Dunaliella Identification Using DNA Fingerprinting Intron-Sizing Method and Species-Specific Oligonucleotides: New Insights on Dunaliella Molecular Identification
• Index