World population in 1960 was about 3 x 109; today it is 5 x 109; and in the year 2000 it is expected to be about 7 x 109. Yes, there is need for protein, vitamins, and minerals -more than can be provided by conventional means. As farmland will be at an ever-increasing premium, non-conventional food sources such as bacteria and yeasts which require organic substrates can be excluded. Photosynthetic aquatic biomass is the only practical resource awaiting general exploitation. Microalgae, with their rapid growth rate, are the most efficient producers of such biomass. And Spirulina (Arthrospira), by virtue of its high available protein and vitamin content (Clement et al., 1967), relative ease of exploitation (Becker & Venkataraman, 1982;Umesh & Seshagiri, 1984), and long history of human consumption (Furst, 1978), is the favored microalga.
Geographic locations of undernutrition coincide with climatic conditions favorable for the growth of Spirulina. Here the great majority of people live in villages. The need for Spirulina biomass cannot be met only by industrial-scale production, for this implies high technology, high overhead, publicity, distribution costs, and profit. Only village-scale production can benefit those with the least money and greatest need.
Recycling of village wastes (human, animal, and vegetal), along with a little ocean salt, can provide the nutrients essential for mass culture of Spirulina while at the same time providing energy, improving health, and increasing both real and effective agricultural output (Fox, 1984). By improving the village economy, Spirulina farming can help reduce the undesirable rush to the overcrowded cities.