Identification of microorganisms associated with castor waste (Ricinus communis)

The aim of this article is to isolate and to identify microorganisms present in the fruit and cake waste of castor (Ricinus communis). Selective culture media for morphological and biochemical characterization were used. For molecular identification, PCR technique was performed with universal primers RM and RB from the bacterial 16S gene and the ITS5 and ITS4 intergenic sequences from molds and yeasts. Sequences were analyzed identifying 9 fungal species being predominant Penicillium brevicompactum; 12 species of bacteria, where genus Bacillus sp. was the most recurrent; and two species of yeast Pichia burtonni and Rhodosporidium paludigenum. The identification of this native microbiota in the waste of castor is very promising, providing a broad knowledge of the metabolic versatility of each of the isolates. The majority of isolates were obtained from the cake by the high content of nutrients in the waste.