Documenting the latest research in the field of different pathogenic organisms, this book presents the current scenario about promising antimicrobials in the following areas: Part I. Plants as source of antibacterials, Part II. Naturally occurring antifungal natural products, Part III. Antiparasitic natural products, Part IV. Antiviral natural products. Renowned scientists from the globe have been selected as authors to contribute chapters. Use of plants for various ailments is as old as human civilization and continuous efforts are being made to improve medicinal plants or to product their bioactive secondary metabolites in high amounts through various technologies. About 200,000 natural products of plant origin are known and many more are being identified from higher plants and micro-organisms. Some plants based drugs are used since centuries and there is no alternative medicine for many such drugs as cardiac glycosides. Drug discovery from medicinal plants or marine micro-organisms continues to provide an important source of new drug leads. Research on new antibacterials represents a real and timely challenge of this century, particularly for the treatment of infections caused by clinical isolates that show multidrug resistance. The main microorganisms involved in the resistance process have been identified and given the acronym ESKAPE for Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa and Enterobacteriaceae. Multidrug resistant Mycobacterium tuberculosis including highly drug-resistant strains (XDR-TB) has also emerged as one of the most important clinical challenges of this century. Plants of diverse taxa and marine micro-organisms are rich source of these antimicrobials. An attempt has been made to compile the recent information about natural sources of antibacterials and their sustainable utilization. Increased panic of these pathogens warrants a growing demand for research to undertake the threat of multidrug resistance. The search for new antifungal, antiparasitic and antiviral natural products is far from devoid of interest. According to the WHO report in 2013, malaria still represents some 207 million cases worldwide and more than 3 billion of people are still exposed to this risk. Similarly, about 350 million people are considered at risk of contracting leishmaniasis. The fight against some viruses also requires that the research on natural products continue. For example, even if an antiretroviral with direct action was recently approved in Europe in 2013, its high cost does not allow to offer it to an exposed population in countries where the cost of drugs remains a problem for a large part of the population. These books are useful to researchers and students in microbiology, biotechnology, pharmacology, chemistry and biology as well as medical professionals.

Part I. Plants as source of antibacterials.- 1. New antimicrobials and resistance modifying agents.- 2. Anti-staphylococcal plant natural products.- 3. Natural products in the fight against gram-negative bacteria.- 4. Multidrug resistance Mycobacterium and natural products.- Part II. Natural occurring antifungal natural products.- 5. Antifungal natural products from marine sources.- 6. Antifungal activities of essential oils from Himalayan plants.- 7. Antifungal activity of Citrus essential oils.- 8. Antifungal compounds from Lactobacillus Part III. Antiparasitic natural products.- 9. Antiplasmodial natural products.- 10. Antitrypanosomal natural products.- 11. Antileishmanial natural products.- 12. Anthelmintic natural products.- Part IV. Antiviral natural products.- 13. Anti-HIV natural products.- 14. Natural products and hepatitis C.- 15. Natural stilbenoids from grapevine against HIV-1 Integrase.- 16. Antiviral products from marine sources.

Prof Merillon agreed to Dr. Kishan Ramawat's (series editor) request to prepare a few books under the series "Sustainable development and Biodiversity". They have discussed these books one by one and this is first book under the series. Dr. Ramawat and Prof Merillon have been collaborating for the past 30 years on various aspects of medicinal plants and produced several books, including one "Plant defence: Biological control" with our group in 2011. He is senior professor at the Bordeaux University.

Dr Céline Rivière is an assistant professor in pharmacognosy at the University of Lille. She belongs to Charles Viollette Institute. She worked in the team of Prof. Mérillon from 2009 to 2011 and she has specialized for afew years in the research of antimicrobials of plant origin.