Chapters authored
Hardwood Tannin: Sources, Utilizations, and Prospects
Tannins are found in widely distributed species of plants, and it protects plant from predators and pests. There are three major groups of tannins, that is, hydrolyzable, complex, and proanthocyanidins. Tannins are being used as a significant element for the tanning of animal hides in the leather production industry from the beginning of tannin industry. Then, these have been used for mineral absorption and protein precipitation purposes since the 1960s. Tannins are used for iron gall ink production and wood-based industry as adhesive and anticorrosive, recovering uranium from seawater and removing mercury and methylmercury from solution. In addition, tannins are considered as bioactive compound in nutrition science, and their possible effects on health are to be identified. This chapter outlines the structural and biological properties of hardwood tannins to indicate the positive utilization of them. It also describes the contemporary information on tannins.
Part of the book: Tannins
The Nanocellulose Fibers from Symbiotic Culture of Bacteria and Yeast (SCOBY) Kombucha: Preparation and Characterization
Symbiotic Culture of Bacteria and Yeast (SCOBY) is a by-product in the form of cellulose polymers produced by bacteria in the kombucha fermentation process. Until now, SCOBY products still have application limitations. Several world designers have succeeded in making works using fabrics based on SCOBY. The resulting fabric has a flexible texture and is brown like synthetic leather. Fabrics based on SCOBY are also considered cheap and more environmentally friendly with short production time. The use of SCOBY as a fabric base material still has problems, where the fabric produced from SCOBY kombucha, directly through the drying process, has the characteristic of being very easy to absorb water. Another problem is that SCOBY production in the kombucha fermentation process is difficult to achieve a uniform thickness and SCOBY production in a large surface area is also difficult to stabilize. The development of SCOBY into cellulose fibers can be done by first changing the structure of SCOBY into nanocellulose. This nanocellulose production can then be developed into nanocellulose fibers in the form of threads and then spun to become a complete fabric. The production of nanocellulose is carried out using cellulase enzymes. It is known that cellulase enzymes can be obtained through the growth of bacteria or specific fungi. One of the groups of fungi and bacteria commonly used to produce cellulase enzymes are Trichoderma and Bacillus.
Part of the book: Nanofibers