BIOTECHNOLOGY - V. H. Gerasymenko - 2006

Part II. Special Biotechnologies

Chapter 24. BIOTECHNOLOGY FOR THE PRODUCTION OF BIOMASS FROM THE UNICELLULAR ALGA SPIRULINA

Spirulina is a blue-green alga widely distributed in nature. Belonging to some of the most ancient plants on Earth, it is over 500 million years old. Global experience demonstrates that cultivating Spirulina for biomass accumulation—with its subsequent use as a food product, animal and poultry feed additive, and raw material for the pharmaceutical industry—is highly viable. In terms of yield and protein output, Spirulina outperforms wheat, corn, and soybeans (Table 24.1).

Class="center">Table 24.1.

Comparative evaluation of Spirulina yield with other crops

(after Albert Sasson, 1987)

The earliest accounts of Spirulina being used for human consumption date back to 1521 in Mexico. It was consumed by ancient Egyptian priests and pharaohs, and highly developed Mayan and Aztec civilizations utilized it in their diets. To this day, Spirulina biomass remains a traditional food source for local populations in Mexico, East Africa, parts of Central America, and India.

Currently, Spirulina is cultivated and utilized in more than 60 countries worldwide. Its annual production in 1995 was as follows:

Mexico - 133 thousand kg of dry matter, USA - 118 thousand kg, Thailand - 110 thousand kg, Japan - 140 thousand kg, Taiwan - 43 thousand kg, India and China - 110 thousand kg each.

In nature, Spirulina grows in freshwater, brackish, and alkaline Water bodies. In the highly alkaline waters (pH up to 11) of Lake Texcoco (Mexico) and the ponds surrounding Lake Chad, Spirulina rapidly multiplies and grows as a monoculture. Spirulina growth continues until The surface of the body of water becomes so dense that it blocks out the light essential for its development.

During an experiment conducted in 1967 by the French Petroleum Institute in cooperation with the Mexican company Sosa Texcoco, Spirulina biomass doubled every 3–4 days in a 900-hectare area of Lake Texcoco. By 1982, the company's production of Spirulina flour reached up to 1,000 tons, valued at $15 million. The primary importers of Mexican Spirulina flour are Japan, the United States, and European countries. The company distributes its products in the form of flour, tablets, and capsules, sold exclusively in health food stores. Spirulina biomass flour is used to manufacture high-protein crackers and confectionery products.

In India, Spirulina is harvested from freshwater ponds and dried water bodies for human consumption. In Israel, it is cultivated in marshes covering up to 12,000 m² (Hills Cure Production Ltd., Haifa). In 1982, the company produced 50 tons of flour, which was used for animal feed and as a human food Supplement.

In Italy, a facility has been built where Spirulina is cultivated in a closed system consisting of polyethylene tubes functioning as solar collectors, which extends the productive season. Experiments in Florence demonstrated that the active growth period for Spirulina in ponds and lakes runs from June to September, whereas in tubular systems, it extends from April to mid-November.

In Ukraine, industrial production of Spirulina for the pharmaceutical industry has been established by the company Spirulina LTD (Mykolaiv). For this purpose, a greenhouse complex was retrofitted to accommodate microalgae cultivation technology. The firm has organized and funded scientific research to investigate biological properties, as well as to develop novel technologies for the cultivation and application of Spirulina in human medicine and Nutrition.

The Feed Institute of the UAAS (Vinnytsia) summarized the experience of Spirulina production and The Use of its biomass for food and feed purposes (Kyryiachenko S.P., Prokopenko L.S., 1995), while the joint-stock company "Rus" in the Zolotonosha district of Cherkasy region developed a facility for the industrial CULTIVATION OF SPIRULINA under artificial conditions using mineral nutrient media in open troughs to utilize the biomass in farm animal feeding (Kyryiachenko S.P., 1994, 1997).

Multi-trough systems for microalgae biomass scaling are widely used in practice. Significant contributions to the improvement of technology and equipment were made by a group of scientists from Kishinev University (Rudykh V.F. et al., 1991).

Spirulina is also cultivated in wastewater to transform residual organic and Mineral Substances, as well as in the liquid fraction of fermented manure (following biogas plant Processing). Some researchers consider it feasible to use Spirulina for wastewater decontamination from heavy metals (mercury, copper, manganese, iron, zinc).