Rhizopus is a genus of molds that includes cosmopolitan filamentous fungi found in soil, decaying fruit and vegetables, animal feces, and old bread.
Schematic diagram of Rhizopus spp.
Rhizopus species produce both asexual and sexual spores. The asexual sporangiospores are produced inside a pinhead-like structure, the sporangium, and are genetically identical to their parent. In Rhizopus, the sporangia are supported by a large apophysate columella, and the sporangiophores arise among distinctive rhizoids. Dark zygospores are produced after two compatible mycelia fuse during sexual reproduction. They give rise to colonies that may be genetically different from their parents.
Some Rhizopus species are opportunistic agents of human zygomycosis. They may cause serious (and often fatal) infections in humans and animals because of their rapid growth rate and growth at relatively high temperatures. Some species are plant pathogens. Two are used in food fermentation: Rhizopus oligosporus, is used in the production of tempeh, a fermented food derived from soybeans and, oncom; R. oryzae is used in the production of alcoholic beverages in parts of Asia and Africa
