Sequential Fermentation

The evaluation of plant-based feedstocks is an important aspect of biorefining. Nicotiana glauca is a solanaceous, non-food crop that produces large amounts of biomass and is well adapted to grow in suboptimal conditions. In the present article, compatible sequential solvent extractions were applied to N. glauca leaves to enable the generation of enriched extracts containing higher metabolite content comparing to direct leaf extracts. Typically, between 60 to 100 metabolite components were identified within the fractions...

The lack of vitamin B12 in unprocessed plant-based foods can lead to health problems in strict vegetarians and vegans. The main aim of this study was to investigate the potential synergy of co-culturing Bifidobacterium animalis subsp. lactis and Propionibacterium freudenreichii in improving production of vitamin B12 and short-chain fatty acids in soy whey. Different strategies including mono-, sequential and simultaneous cultures were adopted. Growth, short-chain fatty acids and vitamin B12 were assessed throughout the fermentation while free amino acids, volatiles, and isoflavones were determined on the final day...

Adaptive immunity relies on specialized effector functions elicited by lymphocytes, yet how antigen recognition activates appropriate effector responses through nonspecific signaling intermediates is unclear. Here we examined the role of chromatin priming in specifying the functional outputs of effector T cells and found that most of the cis-regulatory landscape active in effector T cells was poised early in development before the expression of the T cell antigen receptor. We identified two principal mechanisms underpinning this poised landscape: the recruitment of the nucleosome remodeler mammalian SWItch/Sucrose Non-Fermentable (mSWI/SNF) by the transcription factors RUNX1 and PU...

This study took a novel approach to address the dual challenges of enhancing the ethanol content and aroma complexity in Laiyang pear wine. It focused on sorbitol as a pivotal element in the strategic selection of yeasts with specific sorbitol-utilization capabilities and their application in co-fermentation strategies. We selected two Saccharomyces cerevisiae strains (coded as Sc1, Sc2), two Metschnikowia pulcherrima (coded as Mp1, Mp2), and one Pichia terricola (coded as Tp) due to their efficacy as starter cultures...

Anaerobic digestion in two sequential phases, acidogenesis and methanogenesis, has been shown to be beneficial for enhancing the biomethane generation from wastewater. In this work, the application of glycerol (GOH) as a fermentation co-substrate during the wastewater treatment was evaluated on the biodegradation of different pharmaceuticals and personal care products (PPCPs). GOH co-digestion during acidogenesis led to a significant increase in the biodegradation of acetaminophen (from 78 to 89%), ciprofloxacin (from 25 to 46%), naproxen (from 73 to 86%), diclofenac (from 36 to 48%), ibuprofen (from 65 to 88%), metoprolol (from 45 to 59%), methylparaben (from 64 to 78%) and propylparaben (from 68 to 74%)...

The genetic stability and metabolic robustness of production strains is one of the key criteria for the production of bio-based products by microbial fermentation on an industrial scale. These criteria were here explored in an industrial ethanol-producer strain of Saccharomyces cerevisiae able to co-ferment D-xylose and L-arabinose with glucose through the chromosomal integration of several copies of pivotal genes for the use of these pentose (C5) sugars. Using batch sequential cultures in a controlled bioreactor that mimics long-term fermentation in an industrial setting, this strain was found to exhibit significant fluctuations in D-xylose and L-arabinose consumption as early as the 50th generation and beyond...

Probiotics have been applied to a wide range of bacteria, causing gastrointestinal and vaginal infections. However, probiotics generally possess limited antimicrobial spectra and are primarily utilized as dietary supplements. Recognizing the need for more versatile probiotics, this study focuses on isolating and characterizing strains suitable for antibiotic replacement. Among these strains, Weissella sp. SNUL2, derived from a traditional fermented food in Korea (i.e., Sikhae), emerged as a promising candidate...

H2 -driven microbial electrosynthesis (MES) is an emerging bioelectrochemical technology that enables the production of complex compounds from CO2 . Although the performance of microbial fermentation in the MES system is closely related to the H2 production rate, high-performing metallic H2 -evolving catalysts (HEC) generate cytotoxic H2 O2 and metal cations from undesirable side reactions, severely damaging microorganisms. Herein, a novel design for self-detoxifying metallic HEC, resulting in biologically benign H2 production, is reported...

The establishment of sustainable processes for the production of commodity chemicals is one of today's central challenges for biotechnological industries. The chemo-autotrophic fixation of CO2 and the subsequent production of acetate by acetogenic bacteria via anaerobic gas fermentation represents a promising platform for the ecologically sustainable production of high-value biocommodities via sequential fermentation processes. In this study, the applicability of acetate-containing cell-free spent medium of the gas-fermenting acetogenic bacterium A...

BACKGROUND: Propionic acid fermentation from renewable feedstock suffers from low volumetric productivity and final product concentration, which limits the industrial feasibility of the microbial route. High cell density fermentation techniques overcome these limitations. Here, propionic acid (PA) production from glucose and a crude glycerol/glucose mixture was evaluated using Acidipropionibacterium acidipropionici, in high cell density (HCD) batch fermentations with cell recycle. The agro-industrial by-product, heat-treated potato juice, was used as N-source...

The jabuticaba bark is rich in anthocyanins and fibers, and its use may be of industrial interest. In the food sector, its used as an ingredient in the production of fermented products, liqueurs or enriched flours. It also has pharmaceutical and cosmetic applications. The objective was to evaluate the effect of pretreatment and fresh use of jabuticaba peels in the extraction of total phenolic compound (TPC) and total anthocyanin (TA) contents with and without ultrasound assistance and in the sequential extraction of pectin from the residue...

The dwindling supply of the petroleum product and its carbon footprint has initiated search for a sustainable fuel and alternate feed-stocks. One such underexplored feedstock is chitin, a waste derived from sea food processing. The limitation of insolubility and crystallinity inherent in chitin is addressed with the chitin hydrolysates. In the present study, a chitinases producing marine isolate was isolated from the sediments of Arabian Sea from a depth of 20 m. In order to increase the expression of the chitinases, sequential optimisation using one factor at a time and Taguchi experimental designs were employed which resulted in a yield of 13...

In recent years, the presence of molecules derived from aromatic amino acids in wines has been increasingly demonstrated to have a significant influence on wine quality and stability. In addition, interactions between different yeast species have been observed to influence these final properties. In this study, a screening of 81 yeast strains from different environments was carried out to establish a consortium that would promote the improvement of indolic compound levels in wine. Two strains, Saccharomyces uvarum and Saccharomyces eubayanus, with robust fermentative capacity were selected to be combined with a Saccharomyces cerevisiae strain with a predisposition towards the production of indolic compounds...

BACKGROUND: Spathaspora passalidarum is a yeast with the highly effective capability of fermenting several monosaccharides in lignocellulosic hydrolysates, especially xylose. However, this yeast was shown to be sensitive to furfural released during pretreatment and hydrolysis processes of lignocellulose biomass. We aimed to improve furfural tolerance in a previously isolated S. passalidarum CMUWF1-2, which presented thermotolerance and no detectable glucose repression, via adaptive laboratory evolution (ALE)...

Glycyrrhizic acid, glycyrrhetinic acid, and their oxo, ester, lactone, and other derivatives, are known for their anti-inflammatory, anti-oxidant, and hypoglycemic pharmacological activities. In this study, chryseno[2,1-c]oxepin-12-carboxylic acid (MG) was first biosynthesized from glycyrrhizic acid through sequential hydrolysis, oxidation, and esterification using Aspergillus terreus TMZ05-2, providing a novel in vitro biosynthetic pathway for glycyrrhizic acid derivatives. Assessing the influence of fermentation conditions and variation of strains during culture under stress-induction strategies enhanced the final molar yield to 88...

Hanseniaspora vineae exhibits extraordinary positive oenological characteristics contributing to the aroma and texture of wines, especially by its ability to produce great concentrations of benzenoid and phenylpropanoid compounds compared with conventional Saccharomyces yeasts. Consequently, in practice, sequential inoculation of H. vineae and Saccharomyces cerevisiae allows to improve the aromatic quality of wines. In this work, we evaluated the impact on wine aroma produced by increasing the concentration of phenylalanine, the main amino acid precursor of phenylpropanoids and benzenoids...

The present work models the fermentation process parameters of the newly isolated, Meyerozyma caribbica CP02 for enhanced xylitol production and its fermentability study on rice straw hydrolysate. The study examined the impact of each of the process variables by one variable at a time optimization followed by statistical validation. Temperature of 32 °C, pH of 3.5, agitation of 200 rpm, 1.5% (v/v) inoculum, 80 gL-1 initial xylose was optimized. Subsequently, a sequential two-stage agitation approach was adopted for fermentation...

This study investigated the effects of co-fermentation of T. delbrueckii and S. cerevisiae on the volatile composition and sensory characteristics of blueberry wines. Mixed fermentation led to higher levels of terpenes, higher alcohols, and esters compared to wines fermented with each yeast individually. Conversely, when T. delbrueckii were physically separated from S. cerevisiae in the double-compartment fermenter, contrasting outcomes emerged. The stronger fruity aroma induced by mixed fermentation were linked to higher ester concentrations, including isoamyl acetate, ethyl isovalerate, ethyl hexanoate, and diethyl succinate...

Lactoferrin (LF) stands as one of the extensively investigated iron-binding glycoproteins within milk, exhibiting diverse biological functionalities. The global demand for LF has experienced consistent growth. Biotechnological strategies aimed at enhancing LF productivity through microbial expression systems offer substantial cost-effective advantages and exhibit fewer constraints compared to traditional animal bioreactor technologies. This study devised a novel recombinant plasmid, wherein the AOX1 promoter was replaced with a glucose-inducible G1 promoter (PG1 ) to govern the expression of recombinant porcine LF (rpLF) in Pichia pastoris GS115...

Mixed starter cultures of lactic acid bacteria and yeasts used in the production of fermented foods, including coffee, can improve the sensory quality and food safety. The objective of this study was to evaluate the effects of fermentation of coffee with inoculation of Lactiplantibacillus plantarum followed by Saccharomyces cerevisiae and the effects of fermentation time on the aroma and flavor of the coffee beverage and on the volatile composition of the roasted coffee beans. The coffee was fermented for 48 h or 96 h after inoculation of Lactiplantibacillus plantarum followed by inoculation of Saccharomyces cerevisiae or the respective controls...