Dietary fiber or roughage is the indigestible portion of food derived from plants. It has two main components: 1  Soluble fiber, which dissolves in water, is readily fermented in the colon into gases and physiologically active byproducts, and can be prebiotic and viscous.ietary fiber or roughage is the indigestible portion of food derived from plants. It has two main components: 1  Soluble fiber, which dissolves in water, is readily fermented in the colon into gases and physiologically active byproducts, and can be prebiotic and viscous.
The Portuguese were the first to engage in the New World slave trade in the 16th century. Between 1418 and the 1470s, the Portuguese launched a series of exploratory expeditions that remapped the oceans south of Portugal, charting new territories that one explorer described as oceans where none have ever sailed before.
Africa, Portugal. Portuguese trading stations in West Africa and the slave trade. Portuguese expansion into Africa began with the desire of King John I to gain access to the gold-producing areas of West Africa.ortuguese trading stations in East Africa and the Slave trade. A map drawn in Spain dated 1375, showing the king of Mali holding a gold nugget. Source: British Library. Well-established gold and ivory trade network existed between African kingdoms in the interior and cities on the east coast of Africa.