Fiber fractions from processing of barley in production and conservation of a biologic control agent

Carriers are frequently used to overcome problems associated with microbial survival in soil after inoculation. Moreover, the use of carriers can prol ong the shelf lives and lessen dusting of both biofungicides and biologic f ertilizers. This study investigated the suitability of barley-based fiber f raction; as growth media and immobilization matrices in the cultivation of a Streptomyces grisoviridis biologic control agent, as well as for the cons ervation of obtained biomass in dehydrated hydrogel capsules. The second ma in ingredient in all the examined carrier matrices was alginate. The aim wa s to find a hydrogel formulation suited for a production process in which a ll individual steps, including cultivation of the organism; downstream proc essing; and formulation, storage, and application of the product (i.e., bio logic control agent), are carried out in the hydrogel matrix.. Of the teste d fractions, brewer's spent grain was the best choice, when considering the price vs the nutrient contents as well as the storage time and ease of pro cessing of the crude and the finished products. It seems that cereal fibers can be replenished with cereal fractions less rich in fiber but having a h igher content of utilizable nutrients and, hence, better suited for the pro duction of biomass. A high content of water-insoluble fiber favorably influ enced the appearance as well as the applicability of the products.