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.
Overview. The slave trade began with Portuguese, and some Spanish, traders taking African slaves to the American colonies they had conquered in the 15th century.British sailors became involved in the trade in the 16th century, and the Treaty of Utrecht (1713) gave them the right to sell slaves in the Spanish Empire.he slave trade began with Portuguese, and some Spanish, traders taking African slaves to the American colonies they had conquered in the 15th century.