Natural Nanoparticles: A Particular Matter Inspired by Nature

Abstract

During the last couple of decades, the rapidly advancing field of nanotechnology has produced a wide palette of nanomaterials, most of which are considered as “synthetic” and, among the wider public, are often met with a certain suspicion. Despite the technological sophistication behind many of these materials, “nano” does not always equate with “artificial”. Indeed, nature itself is an excellent nanotechnologist. It provides us with a range of fine particles, from inorganic ash, soot, sulfur and mineral particles found in the air or in wells, to sulfur and selenium nanoparticles produced by many bacteria and yeasts. These nanomaterials are entirely natural, and, not surprisingly, there is a growing interest in the development of natural nanoproducts, for instance in the emerging fields of phyto- and phyco-nanotechnology. This review will highlight some of the most recent—and sometimes unexpected—advances in this exciting and diverse field of research and development. Naturally occurring nanomaterials, artificially produced nanomaterials of natural products as well as naturally occurring or produced nanomaterials of natural products all show their own, particular chemical and physical properties, biological activities and promise for applications, especially in the fields of medicine, nutrition, cosmetics and agriculture. In the future, such natural nanoparticles will not only stimulate research and add a greener outlook to a traditionally high-tech field, they will also provide solutions—pardon—suspensions for a range of problems. Here, we may anticipate specific biogenic factories, valuable new materials based on waste, the effective removal of contaminants as part of nano-bioremediation, and the conversion of poorly soluble substances and materials to biologically available forms for practical uses.

PlantCrystals—Nanosized Plant Material for Improved Bioefficacy of Medical Plants

“…In recent studies by Griffin et al it was shown that various plant materials can be rendered into nanosized particles by using a combination of high speed stirring (HSS) and high pressure homogenization techniques (HPH) [ 3 , 4 , 5 , 6 , 7 , 8 , 9 ]. Diminution of plant materials to sizes < 10 µm means that all plant cells, which typically possess sizes > 10 µm, are destroyed.…”

“…The equipment required is low-cost, freely available and meanwhile established in many laboratories world-wide [ 10 , 11 , 12 , 13 , 14 ]. The feasibility of the PlantCrystal technology was proven in previous studies, where PlantCrystals were shown to increase the antimicrobial and antifungal activity of various plant materials [ 3 , 4 , 5 , 6 , 7 , 8 , 9 ]. Their feasibility to improve antioxidative capacity has not yet been investigated and a systematic study investigating the influence of plant material and process parameters on PlantCrystal size and properties is also not yet available.…”

“…The study was conducted in three steps. In the first step PlantCrystals were produced by using the previously applied production techniques, i.e., a combination of high speed stirring and high-pressure homogenization and subsequent freeze drying [ 3 , 4 , 5 , 6 , 7 , 8 , 9 ]. Different plant materials (leaves, seeds) with well-known antioxidative properties were selected and rendered into PlantCrystals.…”

Inspired by Nature: Redox Modulators and Natural Nanoparticles

“…It is now possible to produce nanoparticles of the relevant plant materials with comparable ease, for instance by milling or fermentation. These nanosized materials are entirely "natural" as far as their chemical composition is concerned, and often exhibit an amazing release profile for active ingredients and therefore also considerable biological activity [11][12][13][14]. Nanosized plant materials rich in biologically active ingredients may therefore unlock the considerable potential of many food items, and possibly also of materials which so far have been considered as "waste", such as the spent coffee ground, grape seeds and various shells, leftovers and peels [15].…”

A distinct pattern of sterile inflammation induced by zinc oxide nanowires.

“…The naturally occurring nanoparticles include volcanic ash soot from forest fires or diesel engines [3][4][5][6]. These naturally occurring nanomaterials are usually physically and chemically heterogeneous [7]. On the other hand, engineered nano-materials (ENMs) are created by the manipulation of matter at the nano-scale to produce new materials and structures [8,9].…”