Note. Nutrient composition of the biomass of the microalga Porphyridium cruentum

Nutritional composition of biomass of several stationary phases of the red microalga Porphyridium cruentum cultured in an external tubular photobiorea ctor is analyzed. The proximate composition (moisture, ash, protein, availa ble carbohydrates, fiber, ARN, lipids and energy), mineral elements (Na, K, Ca, Mg, Fe, Cu, Zn, Mn, Cr, Mn, Co, S), C/N ratio and fatty acids were dete rmined. The mean values of different biomass analyses indicated high propor tions of available carbohydrates (33.2 g/ 100 g d.w.) and protein (34.4 g/1 00 g d.w). Mineral elements content was high, especially Ca (1248 mg /100 g ), K (1219 mg/100 g), Na (1170 mg/100 g), Mg (63.0 mg/100g) and Zn (37.4 mg /100 g). The composition of fatty acids expressed as mg/100 g (dry biomass) was: C16:0 1.73; C18:2 omega 6 0.51; C20:4 omega 6 1.92; C20:5 omega 3 1.6 8. Principal components analyses showed a group of variables formed by lipi ds, ash, Fe,Ca and Zn; and another group formed by available carbohydrates, external irradiance and C/N ratio. According to these, Porphyridium cruent um biomass could be used for nutritional purposes, due to the amount and di versity of nutrients computed and the absence of toxic factors.