Today, scientists find useful applications for compounds from nature but their search methods have changed. Biochemists analyze plants, microorganisms, but many of the things they work with are small even to be seen with a microscope, so they use chemicals to perform experiments. Many of these new inventions are enzymes, biological molecules that are like catalysts for chemical reactions. Sometimes, the only way to get useful organic compound is to get the organism that contains it. But improvements in science, useful compounds can now often be reproduced in a laboratory and sometimes they can be made by genetic engineering. For examples, insulin is a hormone important to human digestion. Many people with diabetes must take insulin as a medicine. The top open access journals are peer reviewed scholarly journals of Biodiversity Bioprospecting and Development. The top open access journals are freely available on the public internet domain, allowing any end users to read, download, copy, distribute, prink, search or link to the full texts of the articles. These provide high quality, meticulously reviewed and rapid publication, to cater the insistent need of scientific community.