Bioengineered最新文献

Substituting waste-derived Volatile Fatty Acids (VFAs) with their conventionally applied fossil-derived counterparts in a spectrum of industrial applications necessitates its proper fractionation into individual acids. This study explored a multi-stage batch adsorption approach for fractionating acidogenic fermentation VFAs effluents from food waste (FW) and chicken manure (CKM) using Diaion HP-20 and activated charcoal. Initial screening at different washing conditions and pH (3.5 and 6.5) revealed the unwashed granular-activated charcoal (GAC-Unwashed) and milli-Q water-washed Diaion (DI-MQ Washed) as the most promising candidates for VFA fractionation of a synthetic VFA mixture at 4 gL^-1. At pH 3.5 ($<p{K}_a$), GAC-Unwashed adsorbed 2-6 carbon atom VFAs completely, while DI-MQ Washed exhibited minimal adsorption of acetic acid (AA) (8%), favoring caproic (CA) and valeric acids (VA) ($>$97%). While at pH 6.5 $(>p{K}_a$), GAC-Unwashed selectively targeted VA (79%) and CA (100%). Fractionating VFAs from FW and CKM were conducted in a two-stage adsorption process with optimal results being achieved using GAC-Unwashed at FW initial pH (5.3) and DI-MQ Washed at pH below CKM $p{K}_a$ (3.5), respectively. The first adsorption stage primarily adsorbed higher molecular weight (MW) VFAs (FW:99.1% CA, CKM:72.9% butyric acid (BA)) with a minor quantity of lower ones (FW:56.5% BA, CKM:29.3% propionic acid (PA)), leaving AA intact. Subsequent stages aimed to isolate AA by adsorbing the remaining low MW VFA (FW:58.9% BA, CKM:27.8% PA, 70% BA) other than AA, indicating effluent fractionation while preserving and purifying AA. Applied selective multi-stage adsorption approach offers a promising method to broaden waste-derived VFA applications.

This article presents new data on the integrated use of colloidal solutions of nanoparticles and low-intensity laser radiation on the biosynthetic activity of the medicinal mushroom Inonotus obliquus in vitro. Traditional mycological methods, colloidal solutions of biogenic metals, and unique photobiological methods have also been used. It was found that colloidal solutions of nanoparticles of all metals used increased the growth characteristics of I. obliquus (55-60%), while irradiation of the fungal inoculum with laser light in a medium with nanoparticles reduced the growth activity of I. obliquus mycelia by 12.3-35.4%. Silver nanoparticles (AgNPs) in a nutrient medium suppressed the biosynthesis of extracellular polysaccharides, whereas laser irradiation in the same medium increased the synthesis of intracellular polysaccharides by 9.7 times. Magnesium nanoparticles (MgNPs) and iron nanoparticles (FeNPs) inhibited the synthesis of intracellular polysaccharides in the mycelial mass of I. obliquus. At the same time, laser irradiation of the inoculum with MgNPs, on the contrary, induced a sharp increase in the amount of polysaccharides in the culture liquid (20 times). Treatment of the inoculum in a medium with nanoparticles with a laser caused an intensification of the synthesis of flavonoids in the mycelial mass and an increase in the synthesis of melanin pigments (25-140%). The results obtained suggest the possibility of the complex use of colloidal solutions of Fe, Ag, and Mg nanoparticles and low-intensity laser radiation as environmentally friendly factors for regulating biosynthetic activity in the biotechnology of cultivating the valuable medicinal mushroom I. obliquus.

Irritable bowel syndrome (IBS) is a common chronic gastrointestinal disorder, with diarrhea-predominant IBS (IBS-D) as the most frequent subtype. The implication of gut microbiota in the disease's etiology is not fully understood. In vitro gut systems can offer a great alternative to in vivo assays in preclinical studies, but no model reproducing IBS-related dysbiotic microbiota has been developed. Thanks to a large literature review, a new Mucosal ARtifical COLon (M-ARCOL) adapted to IBS-D physicochemical and nutritional conditions was set-up. To validate the model and further exploit its potential in a mechanistic study, in vitro fermentations were performed using bioreactors inoculated with stools from healthy individuals (n = 4) or IBS-D patients (n = 4), when the M-ARCOL was set-up under healthy or IBS-D conditions. Setting IBS-D parameters in M-ARCOL inoculated with IBS-D stools maintained the key microbial features associated to the disease in vivo, validating the new system. In particular, compared to the healthy control, the IBS-D model was characterized by a decreased bacterial diversity, together with a lower abundance of Rikenellaceae and Prevotellaceae, but a higher level of Proteobacteria and Akkermansiaceae. Of interest, applying IBS-D parameters to healthy stools was not sufficient to trigger IBS-D dysbiosis and applying healthy parameters to IBS-D stools was not enough to restore microbial balance. This validated IBS-D colonic model can be used as a robust in vitro platform for studies focusing on gut microbes in the absence of the host, as well as for testing food and microbiota-related interventions aimed at personalized restoration of gut microbiota eubiosis.