Fungal-Mediated Biotransformation of Soybean Supplemented with Different Cereal Grains into a Functional Compound with Antioxidant, Anti-Inflammatory and Antitumoral Activities
BIOINTERFACE RESEARCH IN APPLIED CHEMISTRY
Authors: do Prado, Fernanda Guilherme; Miyaoka, Mitiyo Fukuda; de Melo Pereira, Gilberto Vinicius; Binder Pagnoncelli, Maria Giovana; Machado Prado, Maria Rosa; Ribeiro Bonatto, Sandro Jose; Spier, Michele Rigon; Soccol, Carlos Ricardo
Abstract
The aim of this study was to select fungal strains and alternative substrates to increase the production of bioactive compounds by solid-state bioprocessing using soybeans. Initially, from a total of 17 fungi strains, R. oligosporus NRRL 3267, R. oligosporus NRRL 2710, and R. arrhizus NRRL 2582 were pre-selected for presenting the greatest antioxidant activities during soybean fermentation. The three Rhizopus strains were cultured in soybeans supplemented with different cereal grains (brown rice, wheat, corn, and oat) aiming to achieve a higher antioxidant activity. Soybean supplementation with brown rice increased the concentration of phenolic compounds (0.697 to 6.447 mg GAE g-1) significantly compared with the only use of soybean (1.792 to 3.10 mg GAE g(-1)), using R. oligosporus NRRL 2710. The improved fungal-mediated biotransformation process (R. oligosporus NRRL 2710 with soybeans and brown rice) generated an isoflavone aglycone-rich product, containing different antioxidant compounds, such as trans-cinnamic acid, gallic acid, myricetin, quercetin, and kaempferol. The fermented substrate also showed great potential to inhibit hyaluronidase enzyme (anti-inflammatory activity) and against CaCo-2 tumor cells growth (antitumor activity). The resulting compound could serve as a value-added food and/or feed ingredient and a rich source of bioactive compounds.
Transparent exopolymer particles (TEPs)-associated protobiofilm: A neglected contributor to biofouling during membrane filtration
FRONTIERS OF ENVIRONMENTAL SCIENCE & ENGINEERING
Authors: Meng, Shujuan; Wang, Rui; Zhang, Kaijing; Meng, Xianghao; Xue, Wenchao; Liu, Hongju; Liang, Dawei; Zhao, Qian; Liu, Yu
Abstract
Transparent exopolymer particles (TEPs) are a class of transparent gel-like polysaccharides, which have been widely detected in almost every kind of feed water to membrane systems, including freshwater, seawater and wastewater. Although TEP have been thought to be related to the membrane fouling, little information is currently available for their influential mechanisms and the pertinence to biofouling development. The present study, thus, aims to explore the impact of TEPs on biofouling development during ultrafiltration. TEP samples were inoculated with bacteria for several hours before filtration and the formation of "protobiofilm" (pre-colonized TEP by bacteria) was examined and its influence on biofouling was determined. It was observed that the bacteria can easily and quickly attach onto TEPs and form protobiofilms. Ultrafiltration experiments further revealed that TEP-protobiofilms served as carriers which facilitated and accelerated transport of bacteria to membrane surface, leading to rapid development of biofouling on the ultrafiltration membrane surfaces. Moreover, compared to the feed water containing independent bacteria and TEPs, more flux decline was observed with TEP-protobiofilms. Consequently, it appeared from this study that TEP-protobiofilms play a vital role in the development of membrane biofouling, but unfortunately, this phenomenon has been often overlooked in the literature. Obviously, these findings in turn may also challenge the current understanding of organic fouling and biofouling as membrane fouling caused by TEP-protobiofilm is a combination of both. It is expected that this study might promote further research in general membrane fouling mechanisms and the development of an effective mitigation strategy. (c) Higher Education Press 2020