Abstract The use of biopolymers in the preparation of clay mineral-based nanocomposites paves the way for development of an emerging class of bio-nanohybrid systems consisting of unique structural and/or functional properties. Natural polymers such as polysaccharides, polypeptides and proteins, nucleic acids, etc. involved in clay mineral assemblies have key advantages. For example, their character as non-toxic, biodegradable and biocompatible materials leads to hybrid systems that can be considered as green nanocomposites . The terms “polymer-clay” or “biopolymer-clay” are more widely employed in the open and patent literature than the term “clay mineral-based polymer nanocomposite” This latter term is more appropriate nomenclature for clay science and used in this volume. Compared to conventional clay mineral-based polymer nanocomposites, i.e. those involving synthetic polymers, the availability and biocompatibility of natural polymers are quite advantageous. For instance, the polysaccharides starch, cellulose and chitin are some of the most widespread biopolymers in Nature. In order to reduce the environmental impact of plastic waste, certain biopolymers are replacing synthetic non-biodegradable polymers in the preparation of biocomposites (in some cases known as “bioplastics”), which are principally based on starch ( Avella et al. , 2005 ), cellulose ( Park et al. , 2004a and 2004b) and poly(lactic acid) ( Ray and Okamoto, 2003 ). This represents a significant benefit because biopolymers produce environmentally friendly and renewable nanocomposites that reduce the use of synthetic polymers, i.e. those based on petroleum, and consequently reduce the dependence on fossil fuel. Biocompatibility is an additional feature that makes biopolymers very attractive for tissue engineering and

Abstract Similarities can be found in molecular mechanisms operating in biologic cells and those in modern sediments. Organic geochemical data indicate that mineral systems are capable of synthesizing organic monomers such as amino acids, sugars, and urea from CO 2 and ammonia. This fact suggests that minerals in sediments can act as catalysts, in a manner similar to the function of enzymes in cellular systems. Minerals also are capable of synthesizing polypeptides, polysaccharides, or lipids from basic monomers; in brief, like certain macromolecules, minerals function as templates. Interaction mechanisms in sediments introduce coordination changes that can lead to organized structures. Findings from Black Sea sediments support the concept that the lithosphere, and not the atmosphere or hydrosphere, has generated the key components of life. Concentrations of organic carbon, organic nitrogen, phosphorus, amino acids, amino sugars, sugars, ammonia, CaCOs, and other constituents present in Biack Sea sediments are related to regional geologic problems.