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Solid-state fermentation (SSF) is a sustainable method to convert food waste and plant biomass into novel foods for human consumption. Surplus bread crusts (BC) have the structural capacity to serve as an SSF scaffold, and their nutritional value could be increased in combination with perennial ryegrass (PRG), a biorefining feedstock with high-quality protein but an unpleasant sensory profile. SSF with Rhizopus oligosporus was investigated with these substrates to determine if the overall nutritional value could be increased. The BC-PRG SSFs were conducted for up to 72 h, over which time the starch content had decreased by up to 89.6%, the total amino acid (AA) content increased by up to 141.9%, and the essential amino acid (EAA) content increased by up to 54.5%. The BC-PRG SSF demonstrated that this process could potentially valorise BC and PRG, both widely available but underexplored substrates, for the production of alternative proteins., Competing Interests: Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

The first comparative pre-treatment study of Miscanthus (Mxg) and sugarcane bagasse (SCB) using steam explosion (SE) and pressurised disc refining (PDR) pretreatment to optimise xylose and xylo-oligosaccharide release is described. The current investigation aimed to 1) Develop optimised batch-wise steam explosion parameters for Mxg and SCB, 2) Scale from static batch steam explosion to dynamic continuous pressurised disc refining, 3) Identify, understand, and circumvent scale-up production hurdles. Optimised SE parameters released 82% (Mxg) and 100% (SCB) of the available xylan. Scaling to PDR, Miscanthus yielded 85% xylan, highlighting how robust scouting assessments for boundary process parameters can result in successful technical transfer. In contrast, SCB technical transfer was not straightforward, with significant differences observed between the two processes, 100% (SE) and 58% (PDR). This report underlines the importance of feedstock-specific pretreatment strategies to underpin process development, scale-up, and optimisation of carbohydrate release from biomass., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Pretreatment strategies are fundamental to effectively deconstruct lignocellulosic biomass and economically produce biofuels, biomaterials and bio-based chemicals. This study evaluated individual and combinatorial steam explosion (SE) and ionic liquid (IL) pretreatments for production of high-value oligosaccharides from a novel seed-based Miscanthus hybrid (Mx2779). The two ILs used for pretreatment were triethylammonium hydrogen sulphate [TEA][HSO 4 ] and 1-ethyl-3-methylimidazolium acetate [C 2 mim][OAc]. The results showed that each pretreatment leads to distinct effects on the fragmentation (cellulose and xylan dissolution, delignification, deacetylation) and physicochemical modification (cellulose and lignin properties) of lignocellulose. This, in turn, dictated enzymatic hydrolysis efficiencies of the cellulose pulp to glucose or gluco-oligosaccharides for downstream applications. Our findings suggest that the stand-alone SE or [C 2 mim][OAc] pretreatments may offer cost advantages over [TEA][HSO 4 ] through the production of oligosaccharides such as xylo- and gluco-oligosaccharides. This study also highlights technical and economic pretreatment process challenges related to the production of oligosaccharides from Miscanthus Mx2779 biomass., (Copyright © 2020. Published by Elsevier Ltd.)

This study investigated pilot-scale production of xylo-oligosaccharides (XOS) and fermentable sugars from Miscanthus using steam explosion (SE) pretreatment. SE conditions (200 °C; 15 bar; 10 min) led to XOS yields up to 52 % (w/w of initial xylan) in the hydrolysate. Liquid chromatography-mass spectrometry demonstrated that the solubilised XOS contained bound acetyl- and hydroxycinnamate residues, physicochemical properties known for high prebiotic effects and anti-oxidant activity in nutraceutical foods. Enzymatic hydrolysis of XOS-rich hydrolysate with commercial endo-xylanases resulted in xylobiose yields of 380 to 500 g/kg of initial xylan in the biomass after only 4 h, equivalent to ~74 to 90 % conversion of XOS into xylobiose. Fermentable glucose yields from enzymatic hydrolysis of solid residues were 8 to 9-fold higher than for untreated material. In view of an integrated biorefinery, we demonstrate the potential for efficient utilisation of Miscanthus for the production of renewable sources, including biochemicals and biofuels., (Crown Copyright © 2019. Published by Elsevier Ltd. All rights reserved.)

Non- albicans Candida species are growing in prominence in industrial biotechnology due to their ability to utilize hemicellulose. Here, we present the draft genome sequences of an inhibitor-tolerant Candida tropicalis strain (Y6604) and Candida boidinii NCAIM Y01308 T ., (Copyright © 2018 Somani et al.)

Premature and long-term ovarian hormone loss following ovariectomy (OVX) is associated with cognitive impairment. This condition is prevented by estradiol (E2) therapy when initiated shortly following OVX but not after substantial delay. To determine whether these clinical findings are correlated with changes in synaptic functions, we used adult OVX rats to evaluate the consequences of short-term (7-10 d, OVXControl) and long-term (∼5 months, OVXLT) ovarian hormone loss, as well as subsequent in vivo E2 treatment, on excitatory synaptic transmission at the hippocampal CA3-CA1 synapses important for learning and memory. The results show that ovarian hormone loss was associated with a marked decrease in synaptic strength. E2 treatment increased synaptic strength in OVXControl but not OVXLT rats, demonstrating a change in the efficacy for E2 5 months following OVX. E2 also had a more rapid effect: within minutes of bath application, E2 acutely increased synaptic strength in all groups except OVXLT rats that did not receive in vivo E2 treatment. E2's acute effect was mediated postsynaptically, and required Ca(2+) influx through the voltage-gated Ca(2+) channels. Despite E2's acute effect, synaptic strength of OVXLT rats remained significantly lower than that of OVXControl rats. Thus, changes in CA3-CA1 synaptic transmission associated with ovarian hormone loss cannot be fully reversed with delayed E2 treatment. Given that synaptic strength at CA3-CA1 synapses is related to the ability to learn hippocampus-dependent tasks, these findings provide additional insights for understanding cognitive impairment-associated long-term ovarian hormone loss and ineffectiveness for delayed E2 treatment to maintain cognitive functions.

Dielectric spectroscopy (DS) has been used to monitor the simultaneous saccharification and fermentation of lignocellulosic biomass by measuring its dielectric state. However, it is unknown whether following steam explosion (SE) pre-treatment, lignocellulose would still maintain a dielectric state, and, if maintained, whether the dissipation during enzymatic hydrolysis could be monitored. Distillers Dried Grains with Solubles (DDGS), pre-treated by SE, was found to have a capacitance (C = 580 kHz) of approximately 24 pF cm(-1). Following addition of full-strength cellulolytic cocktail A (CC-A; R(2) = 0.97) and 1/3 strength cocktail B (CC-B; R(2) = 0.96), a natural logarithmic decay in capacitance was determined. Furthermore, the DS biomass probes quantified the initial linear rate of dissipation in capacitance during hydrolysis. The rate of CC-B was 34% that of CC-A. These data extend scope and utility of DS biomass probes for monitoring the enzymatic hydrolysis of SE-pre-treated lignocellulosic substrates in real-time., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Increasing the extractable sugar yield from perennial crops is one strategy to generate renewable fuels such as bio-ethanol. Lolium perenne L. (perennial ryegrass) can contain significant (>30% dry matter) water-soluble sugars in the form of polymeric fructan which is readily extracted, broken down and fermented to bio-ethanol. A population of L. perenne generated from four parents which differed in water-soluble carbohydrate (WSC) content was subjected to multiple rounds of selection and recombination on the basis of early spring WSC content to produce a high WSC, and a low WSC population. A control population was generated by selecting the same number of plants at random. The alleles present at six candidate gene loci were analysed before and after selection and correlated to WSC content. Significant differences in the allele frequency of L. perenne soluble-acid invertase1:4 were observed between the three populations with one haplotype significantly associated with the high WSC C2 S+ population (after three rounds of selection and two rounds of recombination). Moreover, WSC content was also associated with biomass accumulation. Thus, in addition to a 2.84-fold increase in WSC yield, the C2 S+ population also had 1.48-fold more biomass per plant, resulting in 3.9-fold higher WSC yield per plant than the control population.

Dielectric spectroscopy (DS) is routinely used in yeast and mammalian fermentations to quantitatively monitor viable biomass through the inherent capacitance of live cells; however, the use of DS to monitor the enzymatic break down of lignocellulosic biomass has not been reported. The aim of the current study was to examine the application of DS in monitoring the enzymatic saccharification of high sugar perennial ryegrass (HS-PRG) fibre and to relate the data to changes in chemical composition. DS was capable of both monitoring the on-line decrease in PRG fibre capacitance (C=580 kHz) during enzymatic hydrolysis, together with the subsequent increase in conductivity (G=580 kHz) resulting from the production of organic acids during microbial growth. Analysis of the fibre fractions revealed >50% of HS-PRG lignocellulose had undergone enzymatic hydrolysis. These data demonstrated the utility of DS biomass probes for on-line monitoring of simultaneous saccharification and fermentation (SSF)., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Although most agree that 17β-estradiol is neuroprotective via a variety of mechanisms, less is known about the role that biological sex plays in receptor-mediated estradiol neuroprotection. To address this issue we isolated primary cortical neurons from rat pups sorted by sex and assessed the ability of estradiol to protect the neurons from death induced by glutamate. Five-minute pretreatment with 10-50 nM 17β-estradiol protected female but not male neurons from glutamate toxicity 24 h later. Both estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) are expressed in these cultures. Experiments using an ERα selective agonist or antagonist indicate that this receptor is important for neuroprotection in female cortical neurons. The ERβ selective agonist conveys a small degree of neuroprotection to both male and female cortical neurons. Interestingly, we found that 17α estradiol and the novel membrane estrogen receptor (mER) agonist STX, but not bovine serum albumin conjugated estradiol or the GPR30 agonist G1 were neuroprotective in both male and female neurons. Taken together these data highlight a role for ERα in sexually dimorphic neuroprotection., (Published by Elsevier Ltd.)

Safeners enhance the selectivity of graminicidal herbicides such as fenoxaprop ethyl in cereals, by increasing their rates of detoxification in the crop. While studying the selectivity of fenoxaprop ethyl in wheat, we determined that the safeners mefenpyr diethyl and fenchlorazole ethyl also enhanced herbicide tolerance in the competing weed black-grass (Alopecurus myosuroides). Fenoxaprop ethyl was detoxified by conjugation with glutathione in both wheat and black-grass, with the resulting metabolites processed to the respective cysteine derivatives, which were then N-glycosylated. In black-grass, these detoxification pathways were only slightly enhanced by safeners, suggesting that metabolism alone was unlikely to account for increased herbicide tolerance. Instead, it was determined that safening was associated with an accumulation of glutathione and hydroxymethylglutathione and enzymes with antioxidant functions including phi and lambda glutathione transferases, active as glutathione peroxidases and thiol transferases respectively. These safener-induced changes closely mirrored those determined in two independent black-grass populations that had acquired multiple herbicide resistance (MHR) in the field. In addition to enhanced glutathione metabolism, both safener treatment and MHR resulted in elevated levels of flavonoids in the foliage of black-grass plants, notably flavone-C-glycosides and anthocyanins. Our results demonstrate that safening in a grass weed is associated with an inducible activation in antioxidant and secondary metabolism which mirrors the biochemical phenotype exhibited in plants that are resistant to multiple classes of herbicides.

Estrogen receptors can activate transcription in the nucleus, and activate rapid signal transduction cascades in the cytosol. Multiple reports identify estrogen receptors at the plasma membrane, while others document the dynamic responses of estrogen receptor to ligand binding. However, the function and identity of membrane estrogen receptors remain controversial. We have used confocal microscopy and cell fractionation on the murine hippocampus-derived HT22 cell line and rat primary cortical neurons transfected with estrogen receptor-green fluorescent protein constructs to address the membrane localization of these receptors. We observe translocation of estrogen receptor beta (beta) to the plasma membrane 5 min after exposure to 17beta-estradiol, whereas estrogen receptor alpha (alpha) localization remains unchanged. Membrane localization of estrogen receptor beta is transient, selective for 17beta-estradiol, and is not blocked by ICI182,780. Inhibition of the mitogen-activated protein kinase pathway does not block estrogen-mediated estrogen receptor beta membrane translocation, and in fact prolongs membrane localization. These data suggest that while both estrogen receptor alpha and estrogen receptor beta can be present at the neuronal membrane, their presence is differentially regulated.

Multiple mechanisms mediate the effects of estrogen in the central nervous system, including signal transduction pathways such as protein kinase A, protein kinase C, and phosphatidylinositol 3-kinase (PI3K) pathways. Previously we demonstrated that estrogen regulates a number of PI3K-related genes in the hypothalamus, including the PI3K p55gamma regulatory subunit. We hypothesized that PI3K activation is critical for the effects of estrogen and that the p55gamma subunit may be more prevalent than the p85alpha regulatory subunit in the hypothalamus. Therefore, in the present study, we compared the mRNA distribution of the p55gamma and p85alpha regulatory subunits by using in situ hybridization in guinea pig. Expression level of p55gamma mRNA was greater than p85alpha in most hypothalamic nuclei. Twenty-four hours of estrogen treatment increased p55gamma mRNA expression in the paraventricular, suprachiasmatic, arcuate, and ventromedial nuclei, and little or no change was observed for p85alpha mRNA. Quantitative real-time PCR confirmed the in situ hybridization results. Next, we investigated the general role of PI3K signaling in the estrogen-mediated changes of arcuate proopiomelanocortin (POMC) neuronal excitability by using whole-cell recording. One cellular mechanism by which estrogen increases neuronal excitability is to desensitize (uncouple) gamma-aminobutyric acid type B (GABA(B)) receptors from their G-protein-gated inwardly rectifying K(+) channels in hypothalamic neurons. We found that the PI3K inhibitors wortmannin and LY294002 significantly reduced the estrogen-mediated GABA(B) receptor desensitization in POMC arcuate neurons, suggesting that PI3K signaling is a critical downstream mediator of the estrogen-mediated rapid effects. Collectively, these data suggest that the interplay between estrogen and PI3K occurs at multiple levels, including transcriptional and membrane-initiated signaling events that ultimately lead to changes in homeostatic function., (Copyright 2007 Wiley-Liss, Inc.)

Numerous preclinical studies suggest that gonadal steroids, particularly estrogen, may be neuroprotective against insult or disease progression. This paper reviews the mechanisms contributing to estrogen-mediated neuroprotection. Rapid signaling pathways, such as MAPK, PI3K, Akt, and PKC, are required for estrogen's ability to provide neuroprotection. These rapid signaling pathways converge on genomic pathways to modulate transcription of E2-responsive genes via ERE-dependent and ERE-independent mechanisms. It is clear that both rapid signaling and transcription are important for estrogen's neuroprotective effects. A mechanistic understanding of estrogen-mediated neuroprotection is crucial for the development of therapeutic interventions that enhance quality of life without deleterious side effects.

Physiological doses of 17-beta Estradiol (E2) rapidly induce mitogen-activated protein kinase (MAPK) phosphorylation in a variety of cell culture and tissue explant preparations. Rapid MAPK phosphorylation has been implicated as a critical step in estrogen's effects on neuronal activity, gene transcription and neuroprotection. The present series of in vivo experiments were designed to determine whether acute administration of estrogen rapidly increased extracellular signal-regulated protein kinase (ERK) 2 phosphorylation. Brains were harvested 20 min after a single i.p. injection of 15 microg/kg of 17-beta or 17-alpha estradiol. Twelve brain structures were micro-dissected, homogenized and processed for Western blotting. E2-treated rats exhibited a statistically significant increase in ERK2 phosphorylation in the diagonal band of Broca, rostral nucleus accumbens, paraventricular nucleus, arcuate nucleus and anteromedial visual cortex. Administration of the same dose of 17-alpha estradiol did not enhance ERK phosphorylation in any of the brain regions examined. The in vivo data presented here extend previously published in vitro data indicating that E2 rapidly activates MAPK in primary neuronal cultures, explants and cell lines. These data also indicate that MAPK activation is a potential mediator of estrogens effects in some but not all estrogen receptor containing regions of the brain.

We have examined the effect of elevated CO2 on the vasculature and phenolic secondary metabolism on clones of the maritime plant Plantago maritima (L.). Plants were exposed to either ambient (360 micromol CO2 mol(-1)) or elevated (600 micromol CO2 mol(-1)) atmospheric CO2 within a Solardome facility and harvested after 12 months' growth. Histochemical analysis of the leaves identified increases in the diameter of the minor leaf vein and associated lignified vessels in plants exposed to elevated CO2. In the roots the number of lignified root vessels and stele width were also increased, but overall the lignified vessel-wall thickness was reduced in plants exposed to elevated CO2, compared to those grown under ambient CO2. To investigate whether or not these subtle changes in lignification were associated with perturbations in phenolic metabolism, aromatic natural products were analysed by HPLC-MS after treatment with cellulase to hydrolyse the respective glycosidic conjugates. The phenylpropanoids p-coumaric acid, caffeic acid, ferulic acid and the flavone luteolin were identified, together with the caffeoyl phenylethanoid glycosides, verbascoside and plantamajoside which were resistant to enzymatic digestion. Exposure to enhanced CO2 resulted in subtle changes in the levels of individual metabolites. In the foliage a one-year exposure to enhanced CO2 resulted in an increased accumulation of caffeic acid, whilst in the roots p-coumaric acid and verbascoside were enhanced. Our results suggest that significant changes in the vasculature of P. maritima on exposure to increased CO2 are associated with only minor changes in the leaves of specific lignin-related metabolites.

The authors have described a subregion of the hamster hypothalamic suprachiasmatic nucleus (SCN) containing cells that are immunopositive for the cytosolic calcium-binding protein, Calbindin-D28K (CaBP). Several lines of evidence indicate that this region may constitute the site of the pacemaker cells that are responsible for the regulation of circadian locomotor rhythms. First, 79% of the CaBP-immunoreactive (ir) neurons express Fos in response to photic stimulation, indicating that they are close to or part of the input pathway to pacemakers. Second, at the light microscopy level, retinal terminals innervate the CaBP subnucleus. Finally, destruction of this subnucleus renders animals arrhythmic in locomotor activity. In this study, the authors examined the ultrastructural relationship between cholera toxin (CTbeta) labeled retinal fibers and the CaBP-ir subregion within the hamster SCN. CTbeta-ir retinal terminals make primarily axo-somatic, symmetric, synaptic contacts with CaBP-ir perikarya. In addition, retinal terminals form synapses with CaBP processes as well as with unidentified profiles. There are also complex interactions between retinal terminals, CaBP perikarya, and unidentified profiles. Given that axo-somatic synaptic input has a more potent influence on a cell's electrical activity than does axo-dendritic synaptic input, cells of the CaBP subregion of the SCN are ideally suited to respond rapidly to photic stimulation to reset circadian pacemakers.

During normal olfaction, stimulation is dependent upon nasal inhalation. When collecting chemosensory event-related potentials (CSERPs), inhalations may produce artifacts such as respiration-related brain potentials that confound interpretation of the data. To avoid this type of artifact, CSERPs have often been collected using stimulation that is independent of respiratory cycle. It is possible, however, that inspirations prime the olfactory tract for odor input, and traditional CSERP data acquisition techniques, obscure this neural preparation. To investigate this question, twelve subjects were tested using two different approaches to stimulation. Odorants (butanol 2% and 4%) were introduced into a warmed and humidified air stream and delivered to one nostril through a cannula. In one condition, subjects mouth-breathed and stimuli occurred asynchronously with respiratory cycle (passive). In the other condition, subjects inhaled through the nose and stimuli were delivered synchronously with nasal inhalations (active). CSERP data were collected from thirty scalp sites for 3 s following stimulation. Data were corrected for eye movements, smoothed, and averaged. Maximal amplitudes for an early negativity (N1) and later positivity (P2) were determined and submitted to separate analyses of variance. These analyses indicated that administration technique interacted with both odor concentration and recording site. Additionally, amplitude of P2 was greater in the passive condition. Such results suggest that the two administration techniques produce different neural processing of olfactory stimuli and that the passive technique may be better suited for determination of the integrity of the olfactory tract for single subjects because of its greater amplitude.