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Over a long period of time, humans have explored many natural resources looking for remedies of various ailments. Traditional medicines have played an intrinsic role in human life for thousands of years, with people depending on medicinal plants and their products as dietary supplements as well as using them therapeutically for treatment of chronic disorders, such as cancer, malaria, diabetes, arthritis, inflammation, and liver and cardiac disorders. However, plant resources are not sufficient for treatment of recently emerging diseases. In addition, the seasonal availability and other political factors put constrains on some rare plant species. The actual breakthrough in drug discovery came concurrently with the discovery of penicillin from Penicillium notatum in 1929. This discovery dramatically changed the research of natural products and positioned microbial natural products as one of the most important clues in drug discovery due to availability, variability, great biodiversity, unique structures, and the bioactivities produced. The number of commercially available therapeutically active compounds from microbial sources to date exceeds those discovered from other sources. In this review, we introduce a short history of microbial drug discovery as well as certain features and recent research approaches, specifying the microbial origin, their featured molecules, and the diversity of the producing species. Moreover, we discuss some bioactivities as well as new approaches and trends in research in this field.

Many thousands of years ago, humans were introduced to the toxicants of minerals and plants of microbial origin, and since that time, natural bioactive compounds have been used in traditional medicine for treating different health conditions, but also as aphrodisiacs and as a means of suicide or murder. Modern medicine acknowledges natural bioactive compounds as valuable medicinal sources for both diagnostic and curative purposes. Natural compounds serve as templates for the production of new drugs with improved pharmacological properties. This book explains the term bioactivity and deals with

Polyphenols are naturally occurring micronutrients that are present in many food sources. Besides being potent antioxidants, these molecules may also possess anti-inflammatory properties. Many studies have highlighted their potential role in the prevention and treatment of various pathological conditions connected to oxidative stress and inflammation (e.g., cancer, and cardiovascular and neurodegenerative disorders). Neurodegenerative diseases are globally one of the main causes of death and represent an enormous burden in terms of human suffering, social distress, and economic costs. Recent data expanded on the initial antioxidant-based mechanism of polyphenols' action by showing that they are also able to modulate several cell-signaling pathways and mediators. The proposed benefits of polyphenols, either as protective/prophylactic substances or as therapeutic molecules, may be achieved by the consumption of a natural polyphenol-enriched diet, by their use as food supplements, or with formulations as pharmaceutical drugs/nutraceuticals. It has also been proved that the health effects of polyphenols depend on the consumed amount and their bioavailability. However, their overconsumption may raise safety concerns due to the accumulation of high levels of these molecules in the organism, particularly if we consider the loose regulatory legislation regarding the commercialization and use of food supplements. This review addresses the main beneficial effects of food polyphenols, and focuses on neuroprotection and the safety issues related to overconsumption.

[Abstract] Mexico is one of the three areas of the world with the greatest terrestrial and cultural biological diversity. The diversity of Mexican medicinal flora has been studied for a long time and several bioactive compounds have been isolated. The investigation of marine resources, and particularly the potential of Mexican marine resources, has not been intensively investigated, even though the Yucatan Peninsula occupies 17.4% of the total of the Mexican coast, with great biological diversity in its coasts and the ocean. There are very few studies on the chemistry of natural products from marine organisms that were collected along the coasts of the Yucatan Peninsula and most of them are limited to the evaluation of the biological activity of their organic extracts. The investigations carried out on marine species from the Yucatan Peninsula resulted in the identification of a wide structural variety of natural products that include polyketides, terpenoids, nitrogen compounds, and biopolymers with cytotoxic, antibacterial, antifouling, and neurotoxic activities. This review describes the literature of bioprospecting and the exploration of the natural product diversity of marine organisms from the coasts of the Yucatan Peninsula up to mid-2019. ; This work was supported by grants RTI2018-093634-B-C22 (AEI/FEDER, EU) from the State Agency for Research (AEI) of Spain, co-funded by the FEDER Programme from the European Union, and GRC2018/039 and ED431E 2018/03 of CICA-INIBIC strategic group from Xunta de Galicia. D.P.P. received a fellowship from the program National Council of Science and Technology (CONACYT) of Mexico and the Secretariat of Research, Innovation and Higher Education (SIIES) of Yucatan (Mexico). O.A.L.R. received a financial support from MostMicro unit. Project LISBOA-01-0145-FEDER-007660 of Portugal ; Xunta de Galicia; GRC2018/039 ; Xunta de Galicia; ED431E 2018/03 ; Portugal. Fundação para a Ciência e a Tecnologia; LISBOA-01-0145-FEDER-007660

This review highlights the recent applications of titanocene(III) complexes in the field of natural product synthesis from the seminal precedents to the development of modern catalytic methods. The power of the titanocene(III)-based approaches is demonstrated by the straightforward syntheses of many natural products from readily available starting materials. ; We thank the Regional Government of Andalucía (project P09-FQM-4571), MICINN (project CTQ-2011.22455), and CEI-Biotic for financial support. SPM thanks the Regional Government of Andalucía for her FPI fellowship. DM and AGC thank the Regional Government of Andalucía and the MICINN ( Juan de la Cierva) for their postdoctoral contracts.

Chemical compounds isolated from natural sources offer unique opportunities to understand life on a molecular level. In this account, an overview over different natural products investigated in our research group over the last decade is presented. We have shown that protein localization in living cells can be controlled by anguinomycins and derivatives. Furthermore, a truncated analog, SB640, was discovered that retained much of the natural product potency. Detailed studies of the iron chelator anachelin led to the development of a bio-inspired platform for the generation of bioactive interfaces. The discovery of natural products isolated from cyanobacteria such as nostocarboline, aerucyclamides, cyanopetolin 1020 and various microcystins is presented and their molecular mechanisms of action were investigated. The last part describes the synthesis and evaluation of various natural products involved in neuritogenesis and synapse reconstruction such as withanolide A, militarinone, farinosone A and C and torrubiellone C. Their potential with regard to their use in regenerative medicine is discussed.

There is a tremendous level of worldwide interest in marine natural productswith therapeutic potential in industry, academia, and government resea rchlabs, largely because natural products generally continue to be viewed as o neof the few de novo sources of drug discovery, yielding unorthodox and oftenunexpected chemical st ructures that offer nove l points of de pa rture for molecularmodification leading to clinically ava il able drugs (de Souza et a l. 1982). ; Florida Atlantic University. Harbor Branch Oceanographic Institute contribution 908 ; This manuscript is an author version with the final publication available and may be cited as: McConnell, O. J., Longley, R. E., & Koehn, F. E. (1994). The discovery of marine natural products with therapeutic potential. In V. P. Gullo (Ed.), The discovery of natural products with therapeutic potential (pp. 109-174). Boston: Butterworth-Heinemann.

Abstract: The global medicine market is about 1.1 trillion US dollars. About 35 percent of medicines have originated from natural products. Brazil presents the largest biodiversity in the world, with more than 50,000 species of higher plants. However, few innovative products have been developed in Brazil from active constituents derived from the Brazilian biodiversity. Scientific evidences on plants and venoms have been internationally published by Brazilian scientists over the last 4 decades; but few examples of innovative products are commercially available. Few examples include the anti-hypertensive drug captopril first identified in the venom of the Brazilian viper Bothrops jararaca by Professor Sergio Ferreira; and some phytotherapeutic agents such as Acheflan®, Syntocalmy® and Melagrião® produced by standardized plant extracts with scientific proof of safety, efficacy and quality. Still, only Acheflan® and Melagrião® are obtained from native Brazilian plants. Several issues contribute to the lack of innovative products from the Brazilian biodiversity, but in my opinion, the most challenging ones are i) the lack of specific regulations to allow researchers and companies to access biodiversity for the purposes of scientific and technological innovation; and ii) the absence of a long-term government program to support research and innovation in this field.

During the past 20 years, marine chemical ecology has emerged as a respected field of study providing a better understanding of the role natural products play in organisms and their environments. Ample data in this book advocates the conservation of marine environments for future drug discovery efforts while sustaining their overall health. Marine chemical ecology has expanded to include research in the areas of predator–prey interactions, marine microbial chemical ecology, and seasonal and geographical distribution of marine natural products