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We study responses of thermally annealed ultrathin films deposited on silicon substrates and containing polyzwitterions to applied electric fields by using specular neutron reflectometry (NR). In particular, we applied 7 kV under vacuum at 150 °C on the films containing poly(1-(3-sulfonatopropyl)-2-vinylpyridinium) (P2VPPS) and its blends with either a deuterated ionic liquid (EMIMBF4-d11), potassium bromide (KBr), or deuterated sodium polystyrenesulfonate (NaPSS-d7). The voltage was applied over an air gap, and the in situneutron reflectivity measurements allowed us to measure changes in the films. In all the cases, we measured decreases in thicknesses of the films, which varied up to ∼8% depending on the added salt. PosterioriX-ray reflectivity (XRR) measurements on the same films at room temperature reveal that these films were highly hygroscopic, which led to the presence of water in these films. Analysis of the NR and the XRR revealed that the decrease in the thickness of the films in the neutron reflectivity experiments on heating resulted from the loss of water and the ionic liquid but not from electrostrictive effects. The in situNR and posterioriXRR experiments revealed not only the hygroscopic nature of these films but also depth-resolved structural rearrangements due to the applied electric fields in the films containing electrolytes and polyelectrolytes. This work shows that a combination of NR and XRR can be used to distinguish between mass loss and electrostriction in films containing charged polymers such as polyzwitterions.

There are two opposing views on the role of the melting of low-entangled polyethylenes on the obtained entanglement density in the molten state and the time required for its equilibration, namely, instantaneous recovery to the equilibrium melt state upon melting (chain explosion) versus slow recovery (melt memory effect). A series of rheological studies have shown that slow heating of low-entangled nascent ultrahigh-molecular-weight polyethylene (UHMWPE) powders to temperatures above the equilibrium melting temperature causes the formation of “the disentangled nonequilibrium melt” due to consecutive detachment of chain stems from the edges of crystals keeping the largely intact low-entangled middle part of chains in the melt. Contrary to the rheology findings, studies of several mechanical properties of recrystallized UHMWPE have found that the equilibrium entanglement density is reached instantly upon the melting of low-entangled UHMWPE, suggesting a chain explosion mechanism. To obtain additional information that can help in understanding the melt memory phenomenon better, several UHMWPE samples are studied by 1H NMR T2relaxometry. The NMR experiments are performed for melts prepared from UHMWPE powders with different entanglement densities that were molten using fast (∼10 K/min) and slow (∼0.2 K/min) heating rates. In all cases, the existence of “the disentangled nonequilibrium melt” was not observed. The results are explained by the chain explosion mechanism that leads to the equilibrium volume-average entanglement density, already at the final stage of melting. Cautious rheological experiments also do not detect “the disentangled nonequilibrium melt”. Possible artifacts of previous rheological studies of disentangled UHMWPE melts are discussed. The conclusion of the present study is supported by a large number of previous investigations that are briefly reviewed. Is the disentangled melt state fictitious or real? The answer is yes and no. Chain explosion causes instantaneous equilibration of the volume-average entanglement density upon melting by the formation of local entanglements that play a major role in several volume-average properties, i.e., modulus, drawability, adhesion, segmental mobility, and some other properties. However, the uniform distribution of topological knots between chains is a slow process that is largely governed by chain reptation. The heterogeneity of the entanglement network as well as the impurities in UHMWPE can influence (1) the local nucleation phenomenon at crystallization that does not characterize the entanglement network and (2) deformation properties at ultimate strains. Therefore, the definition of melt memory and chain explosion should be specified to properties that are used for the characterization of low-entangled and equilibrium melt states.

IMPORTANCE: Since bilateral simultaneous postoperative endophthalmitis (BSPOE) after immediate sequential bilateral cataract surgery (ISBCS) can be devastating for the patient, evaluating such cases in depth is important to maintaining patient safety. OBJECTIVE: To evaluate whether a systemic breach of sterility was associated with an outbreak of BSPOE after ISBCSs performed on the same day at a single community-based eye clinic. DESIGN, SETTING, AND PARTICIPANTS: This retrospective case series included all patients diagnosed with BSPOE at ophthalmology departments in Denmark following an infectious outbreak after ISBCSs performed at a single community-based eye clinic in December 2022. EXPOSURE: Bilateral simultaneous postoperative endophthalmitis acquired after ISBCS. MAIN OUTCOME AND MEASURES: Patient recovery from BSPOE after ISBCS was evaluated based on clinical and microbiological reports. RESULTS: A woman aged 71 years, a man aged 84 years, and a woman aged 79 years consecutively presented with symptoms of endophthalmitis at regional eye departments 4 to 8 days after ISBCS performed on the same date at the same eye clinic. Five of 6 infected eyes underwent vitrectomy, and all eyes received an intravitreous injection of antibiotics. The same strain of Staphylococcus epidermidis was isolated in 4 of 5 eyes that underwent vitrectomy. Contamination of viscoelastics was ruled out with repeated cultures. One eye was eviscerated due to phthisis. In another patient, the final visual acuity of the eye most severely affected was 20/63 Snellen equivalents. Visual acuity of the remaining eyes recovered to 20/25 (3 eyes in 2 patients) and 20/20 (1 eye) Snellen equivalents. CONCLUSIONS AND RELEVANCE: The finding of the same strain of S epidermidis in all patient cultures suggests a systemic breach of sterility at the clinic on the day of ISBCS. The outcome of these cases emphasizes the need to adhere to a strict surgical methodology and sterile principles during ISBCS.

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It is well known that ultra‐high molecular weight polyethylene (UHMWPE) is a polymer with long chains and very high molecular weight that poses difficulties in terms of processability due to the presence of chain entanglements. In many cases is thus necessary to treat the material in different ways after the polymerization to minimize the amount of entanglements and improve the processability. Based on observations that the use of inert condensing agents (ICA) had a noticeable impact on molecular weight and crystallinity, it was decided to develop a gas‐phase polymerization process with addition of ICA for UHMWPE with a high fraction of disentangled chains. For the optimization of this process, the comparison with slurry is important for the understanding the improvement. Thus, a clear difference between slurry and gas phase is observed in terms of crystallinity and the lamellar thickness of the crystals, molecular weight and entanglements. Characterization techniques are developed to measure the properties of the reactor powder and understand the impact of the alkanes in situ. Using solid‐state drawability, the entanglement degree of the reactor powder is analyzed. From the small‐angle x‐ray scattering and wide‐angle x‐ray scattering techniques, it is possible to find a correlation of entanglements and lamellar thickness. Moreover, crystallization kinetics measurements of the polymer in presence of ICA constitutes a powerful method to explain the phenomena of entanglement and crystal formation.

Around birth, globin expression in human red blood cells (RBCs) shifts from γ-globin to β-globin, which results in fetal haemoglobin (HbF, α2γ2) being gradually replaced by adult haemoglobin (HbA, α2β2)1. This process has motivated the development of innovative approaches to treat sickle cell disease and β-thalassaemia by increasing HbF levels in postnatal RBCs2. Here we provide therapeutically relevant insights into globin gene switching obtained through a CRISPR–Cas9 screen for ubiquitin–proteasome components that regulate HbF expression. In RBC precursors, depletion of the von Hippel–Lindau (VHL) E3 ubiquitin ligase stabilized its ubiquitination target, hypoxia-inducible factor 1α (HIF1α)3,4, to induce γ-globin gene transcription. Mechanistically, HIF1α–HIF1β heterodimers bound cognate DNA elements in BGLT3, a long noncoding RNA gene located 2.7 kb downstream of the tandem γ-globin genes HBG1and HBG2. This was followed by the recruitment of transcriptional activators, chromatin opening and increased long-range interactions between the γ-globin genes and their upstream enhancer. Similar induction of HbF occurred with hypoxia or with inhibition of prolyl hydroxylase domain enzymes that target HIF1α for ubiquitination by the VHL E3 ubiquitin ligase. Our findings link globin gene regulation with canonical hypoxia adaptation, provide a mechanism for HbF induction during stress erythropoiesis and suggest a new therapeutic approach for β-haemoglobinopathies.

Ultrahigh molecular weight polyethylene (UHMWPE) is a high-end engineering polymer. However, the very features that lead to its exceptional properties, i.e., ultralong macromolecular chains, render joining two surfaces of this material a tedious and slow process, leading to long welding times and impeding mechanical recycling of UHMWPE. Here we report the anomalous fast joining of UHMWPE interfaces by simply depositing small amounts of nascent disentangled UHMWPE powder at the interface. The time evolution of buildup of adhesive fracture energy in the molten state and the reduction in interfacial slip between two molten UHMWPE layers reveal an orders of magnitude increase of the rate of interpenetration compared to the dynamics of a regular UHMWPE–melt interface. This ultrafast self-diffusion mechanism is insensitive to molecular weight, in contrast to reptation-driven diffusion, and provides a direct indication of the entropy-driven “chain explosion” upon melting of nascent disentangled UHMWPE. The usefulness of fast molecular stitching is demonstrated for enhanced recycling of UHMWPE.

The melting-induced change in the density of physical network junctions, which are formed by chain entanglements and network junctions due to anchoring of chain segments to crystals, is studied by 1H NMR T2relaxometry for solution- and melt-crystallized ultrahigh-molecular-weight polyethylene (UHMWPE), sc-UH, and mc-UH, respectively. The NMR results are complemented by real-time synchrotron wide- and small-angle X-ray scattering (WAXS and SAXS) analyses to extract the sizes of the crystalline lamellae and intercrystalline domains. Below the melting temperature, the network of physical junctions is denser in the amorphous phase of mc-UH than the one in sc-UH owing to a lower entanglement density and a smaller number of physical junctions from polymer crystals in sc-UH. However, the difference in the total density of physical junctions between mc-UH and sc-UH films decreases with decreasing crystallinity during melting. At the end of the melting trajectory, at vanishing crystallinity, the volume-average entanglement density, as characterized by the NMR method, is approximately the same in sc- and mc-UH. This indicates that the entanglement density in sc-UH films increases during melting owing to the fast buildup of local chain entanglements. These entanglements are formed by segments of the same chain, neighboring chains, or both due to a displacement of chain fragments upon lamellar thickening and due to the so-called “chain explosion” that occurs locally in the amorphous domains. The increase in the entanglement density in sc-UH is additionally confirmed by the solid-state drawability of sc-UH films that were annealed in the melting region but below the end of melting. The maximum draw ratio decreases and the drawing stress increases with the increasing annealing temperature.

Platelet recovery is delayed after umbilical cord blood transplant (UCBT). Romiplostim is a thrombopoietin receptor agonist that has the potential to improve platelet engraftment after UCBT. The purpose of this study was to determine the safety profile and maximum tolerated dose (MTD) of romiplostim and to investigate whether romiplostim accelerates platelet recovery post-UCBT. It was a single-center, dose-finding, safety and tolerability phase I trial of weekly romiplostim in 20 adult patients who failed to achieve an un-transfused platelet count of 20 × 109/L by day +28 post-UCBT. Romiplostim was administered at the assigned dose as 6 weekly injections beginning by day +42 post-UCBT. Four dose levels (4, 6, 8, and 10 µg/kg per dose) were evaluated. The MTD of romiplostim was determined by the continual reassessment method, with a goal to identify a dose level with desired toxicity rate of ≤20%. Median age of the patients was 59.5 years, and 60% were female. Eleven patients received nonmyeloablative (NMA) double UCBT, seven patients received myeloablative single UCBT, and two patients received NMA single UCBT. Two patients received 4 µg/kg per dose, two received 6 µg/kg per dose, four received 8 µg/kg per dose, and the remaining 12 received 10 µg/kg per dose. Only five patients completed the full six doses of treatment. Of the 15 patients who received fewer than six doses, 12 were due to a platelet count of >100 × 109/L, two were due to platelet count of >400 × 109/L, and one was due to right upper extremity edema without thrombosis. All romiplostim-treated patients achieved platelet engraftment to 20 × 109/L at a median of 45 days post-UCBT compared to 90% of controls at a median of 45 days (P = .08). Similarly, 90% of romiplostim-treated patients achieved platelet engraftment to 50 × 109/L at a median of 48 days compared to 75% of controls at a median of 52 days (P = .09). All dose levels were effective with low toxicity; therefore, the MTD of romiplostim was 10 µg/kg per dose, and romiplostim is a safe and potentially effective therapy to counter delayed platelet recovery post-UCBT.

Corrosion and wear pose significant challenges to equipment operating in harsh environments. Thus, protective coatings are needed. Anti-corrosion and anti-wear coatings are traditionally fossil-based and often contain environmentally harmful additives. Achieving anti-corrosion and anti-wear coatings based on environmentally benign and sustainable materials is important and a significant challenge. This work focused on the development of organosolv lignin-based polyurethane (OS_lignin-PU) coatings. The coatings were synthesised and evaluated for corrosion protection using electrochemical impedance spectroscopy (EIS) and for wear properties using nanoindentation and nano scratch measurements. EIS revealed that the optimal lignin content for corrosion protection purposes in the OS_lignin-PU coatings was 15 wt%. Moreover, addition of 15 wt% lignin to the OS_lignin-PU coatings also enhanced their wear resistance, as evidenced by reduced thickness loss during tribometer tests. The nano scratch measurements revealed that OS_lignin-PU coatings containing 15 wt% lignin exhibited the lowest scratch depth and friction coefficient. It is found that the developed lignin-containing coating exhibits remarkable corrosion and wear resistance, making it a promising sustainable material in various applications for pursuing sustainable development.

In β-thalassemia, mutations in the HBBgene cause reduced β-globin synthesis with accumulation of toxic free α-globin, leading to ineffective erythropoiesis and hemolysis. We showed previously that β-thalassemic erythroblasts can eliminate free α-globin by ULK1-mediated autophagy and that this process is stimulated by rapamycin inhibition of mTORC1, which phosphorylates ULK1 to inhibit its activity. Several studies have shown that iron restriction can reduce the accumulation of free α-globin precipitates to alleviate the pathophysiology of β-thalassemia. Considering that iron stimulates mTORC1 activity in numerous cell types including erythroblasts, we tested the hypothesis that iron restriction alleviates β-thalassemia by inhibiting mTORC1, thereby stimulating ULK1-mediated autophagy of free α-globin.

High patient radiation dose during chronic total occlusion (CTO) percutaneous coronary intervention (PCI) might lead to procedural failure and radiation skin injury.

Retinal intravascular lipid aggregates were detected in the left eye in a patient with uncontrolled diabetes and very high blood triglycerides. The patient suffered visual loss in the left eye due to retinal ischemia. Optical coherence tomography, fluorescein angiography, infrared fundus photography, and autofluorescence studies of the retina demonstrated unique findings. Slowed choroidal and retinal flow was detected on fluorescein angiography, and a prominent middle layer membrane sign was present on OCT. Intravascular lipid reflectivity was manifest on retinal infrared and autofluorescence imaging. Eventually, insulin and statin therapy proved effective in reversing the vascular lesions, although retinal atrophy finally ensued. This report of a very rare clinical condition provides unique findings on multimodal retinal imaging and confirms the need for prompt insulin and statin therapy in severe/extreme hypertriglyceridemia and dysregulated diabetes. One similar case was reported in the past when multimodal imaging studies of the retina were not available. The lesions described herein should be differentiated from the more frequently encountered lipemia retinalis as they may confer worse prognosis.

•Loss of miR-144/451in erythroid cells of Hbbth3/+mice alleviates β-thalassemia by stimulating ULK1-dependent autophagy of free α-globin.•Loss of miR-144/451stimulates ULK1 by activating the LKB1/AMPK axis and inducing erythroblast iron restriction.

There is ongoing controversy about the optimal crossing strategy selection for chronic total occlusion (CTO) percutaneous coronary intervention (PCI), especially regarding the relative merits of antegrade dissection/re-entry and the retrograde approach.

Production of bio-based chemicals nowadays is more crucial than ever. The fact that 3-Hydroxypropionic acid can serve as a building block chemical for the production of other high added value chemicals, has made it as one of the most valuable chemicals according to US DOE. Recently, researchers have turned their interest to the construction of a microbial cell factory that will be capable of producing 3-hydroxypropionic acid from renewable raw materials. Most of the work is dedicated to the utilization of glycerol as raw material by employing either Escherichia coli or Klebsiella pneumoniae strains. Several genes were tested and evaluated and different cultivation techniques were applied. During the last few years, promising levels of 3- hydroxypropionic acid were obtained, however more efforts have to be dedicated in this direction of the commercialization of the process that seems to be closer than even before.

Second‐generation bioethanol produced from various lignocellulosic materials, such as wood, agricultural, or forest residues, has the potential to be a valuable substitute for, or a complement to, gasoline. At least three major factors—rapidly increasing atmospheric CO2levels, dwindling fossil fuel reserves, and their rising costs—suggest that we now need to accelerate research plans to make greater use of plant‐based biomass for energy production and as a chemical feedstock as part of a sustainable energy economy. Optimizing the production of bioethanol to be competitive with petrochemical fuels is the main challenge for the underlying process development. The exhaustive research on enzyme technology during the latest years, resulting in significant advances in the field, show the importance of the enzymatic hydrolysis for a profitable ethanol production process. On the other hand, the persisting challenges in biomass pretreatment, which are the initial steps in most process designs, show the remarkable recalcitrance of the lignocellulosic materials to biological degradation. The recent scientific trends show toward an integrated overall bioconversion process in which fermentation technology and genetic engineering of ethanologenic microorganisms aim not only at maximizing yields and productivities but also at widening the range of fermentation products and applications. This article is categorized under: Bioenergy > Science and Materials

In this study we maximized biomass production by the basidiomycete Ganoderma australeATHUM 4345, a species of pharmaceutical interest as it is a valuable source of nutraceuticals, including dietary fibers and glucans. We used the Biolog FF MicroPlate to screen 95 different carbon sources for growth monitoring. The pattern of substrate catabolism forms a substrate assimilation fingerprint, which is useful in selecting components for media optimization of maximum biomass production. Response surface methodology, based on the central composite design was applied to explore the optimum concentrations of carbon and nitrogen sources of culture medium in shake flask cultures. When the improved culture medium was tested in a 20‐L stirred tank bioreactor, using 13.7 g/L glucose and 30.0 g/L yeast extract, high biomass yields (10.1±0.4 g/L) and productivity of 0.09 g L−1h−1were obtained. The yield coefficients for total glucan and dietary fibers on biomass formed were 94.82±6 and 341.15±12.3 mg/g mycelium dry weight, respectively.

Mushrooms comprise a vast source of new pharmaceutical and nutraceutical products. Submerged fermentation of the mycelial form of mushroom-producing fungi is promising for efficient production of their biomass and active metabolites. The aim of this study was the isolation and identification of bioactive metabolites derived from the edible mushroom Pleurotus ostreatus biomass, produced by submerged fermentation in a batch stirred tank bioreactor. The dichloromethane extract was fractioned by medium pressure liquid chromatography (MPLC) and Sephadex LH-20 column chromatography. For extracting efficiently the phenolic compounds of the methanolic extract, an adsorption-desorption process, using XAD-4 type resin, was performed. The pure compounds were elucidated with 1D/2D NMR-spectroscopic analyses, NMR data comparisons, and chemical correlations combined with GC/MS- LC/MS experiments. The compounds afforded by the dichloromethane extract were identified as linoleic acid (1), oleic acid (2), stearic acid (3), palmitic acid (4) and their corresponding methyl esters (5-8, respectively), benzoic acid (9), trans 3, 4-dihydro-3, 4, 8-trihydroxynapthalen-1(2H)-one (10), 4-hydroxy- benzaldehyde (11), indolo-3-carboxylic acid (12) and uracil (13). The investigation of the methanolic extract led to the isolation of 3-formyl-pyrrole (14), 4-hydroxy-benzoic acid (15), uridine (16), nicotinic acid (17) and nicotinamide (18). Based on existing literature data, all these compounds exhibit valuable biological properties. The information obtained is considered fundamental for further investigation of the P. ostreatus fermentation process on an industrial scale for enhanced bioactive metabolite production.

BackgroundHyperleukocytosis is observed in 5% to 20% of patients with newly diagnosed acute myeloid leukemia (AML) and is associated with an increased risk of early complications and mortality. While being used frequently in patients with AML and hyperleukocytosis, the clinical utility of leukapheresis has not been conclusive. Low-dose chemotherapy has also been used recently as a cytoreduction method in these patients, but the data are limited.

Pui: Adaptive Biotechnologies: Membership on an entity's Board of Directors or advisory committees; Novartis: Other: Data Monitoring Committee.

The increasing environmental impact of fuels and chemicals from non-renewable fossil-based resources, as well as possible depletion of the latter, has spurred interest in sustainable alternatives. Fuels and chemicals can be produced in a carbon-neutral manner from renewable feedstock via biological processes. Short-and medium-chain fatty acids (SCCA and MCCA, respectively) have potential applications in the food, pharmaceutical, chemical, and biofuel industries. Microbial production of valuable elongated MCCA from SCCA requires an electron donor. The present study investigated the influence of ethanol as an electron donor for the mixed microbial fermentation of SCCA (C2-C5) and MCCA (C6) from brewery spent grains as feedstock. Chain elongation of SCCA to MCCA was evaluated under different ethanol concentrations (3, 6, 9, 12, 15, and 18 g/L) and compared with a non-ethanol control. Acidogenic fermentation successfully converted brewery spent grains to SCCA, reaching 19.66 gCOD/L (15 g/L ethanol supplementation) along with bio-hydrogen production of 41%. Accumulated SCCA were elongated to MCCA in a reverse βoxidation pathway to 9.1 gCOD/L of caproic acid (9 g/L ethanol). Ethanol consumption displayed a good correlation with MCCA formation, confirming the chain elongation capability of mixed cultures. Volatile solids were reduced by more than 70%. Continuous hydrolysis of the substrate with the release of sugars points to the beneficial role of mixed culture fermentation for the production of renewable fuels and chemicals.

Microbial Electrosynthesis (MES) is emerging as a promising technology for the decarbonization of the economy. The use of CO2as a feedstock, i.e. through carbon capture and utilization, can create attractive business opportunities for the production of third generation biofuels. Achieving highly efficient electron transfer from the cathode to microbes is one of the main challenges hindering the development of MES reactors. It is, therefore, essential to improve biofilm growth for enhanced electron-transfer during bioconversion.

A 32central composite experimental design was performed with the aim of optimizing the production of xylanase by Sporotrichum thermophilegrown on corn cobs in submerged cultures. Various carbon and nitrogen sources were consecutively optimized, and corn cobs and ammonium phosphate concentrations were selected as substrates to test the effect of two variables, i.e., both substrate concentrations, on xylanase production. A second‐order quadratic model and a response surface method showed that the optimum conditions for xylanase production were 2.7 % [w/v] corn cobs and 0.7 % [w/v] ammonium phosphate. These optimum conditions were transferred to 7 L bioreactors, where activities as high as 56 U/mL were obtained.

A 32central composite experimental design was performed with the aim of optimizing xylanase production by Thermomyces lanuginosusgrown on corn cobs in submerged cultures. Xylanase production was first tested on different nitrogen sources (tomato skin, tomato seed meal, corn steep liquor, meat peptone, bacto-tryptone and yeast extract). Tomato seed meal was the selected substrate to test the effect of two variables on xylanase production (corn cobs and tomato seed meal concentrations). A second-order quadratic model and a response surface method showed that the optimum condition for xylanase production was corn cobs 4.6% (w/v) and tomato seed meal 2.1% (w/v). The optimum conditions found were transferred to 7-l bioreactors, where activities as high as 1630 U/ml were obtained.A 32central composite experimental design was performed with the aim of optimizing xylanase production by Thermomyces lanuginosusgrown on corn cobs in submerged cultures. Xylanase production was first tested on different nitrogen sources (tomato skin, tomato seed meal, corn steep liquor, meat peptone, bacto-tryptone and yeast extract). Tomato seed meal was the selected substrate to test the effect of two variables on xylanase production (corn cobs and tomato seed meal concentrations). A second-order quadratic model and a response surface method showed that the optimum condition for xylanase production was corn cobs 4.6% (w/v) and tomato seed meal 2.1% (w/v). The optimum conditions found were transferred to 7-l bioreactors, where activities as high as 1630 U/ml were obtained.

Production of β-fructofuranosidase from the thermophilic fungus Thermoascus aurantiacuswas enhanced by optimization of the type of nitrogen source as well as the type and concentration of carbon source. Submerged batch cultivation in a laboratory bioreactor (7 l) using the optimized medium allowed the production of 85 mU/ml of β-fructofuranosidase. The enzyme showed both transfructosylating and hydrolytic activities and was optimally active at 60 °C and pH 5.0. The enzyme showed the ability to catalyse the synthesis of 1-kestose and the reaction was maximized at 30% (w/v) initial sucrose concentration.

Corn cobs are important by‐products of the sweet corn processing industry. A large quantity of corn cobs thus generated remains unused as cellulosic wastes in fields and factories or used as animal feed. As in the field of other agro‐industrial plant cell‐wall waste materials, academic and industrial researchers are putting more and more effort into obtaining high‐value compounds from this waste, which can be converted into novel consumer goods by the industries involved.

Production of feruloyl esterases (FAEs) by Fusarium oxysporumwas enhanced by optimization of initial pH of the culture medium, the type and concentration of nitrogen and carbon source. Submerged batch cultivation in a laboratory bioreactor (17 l) produced activity at 82 nkat g−1dry substrate (corn cobs) which compared favorably to those reported for the other microorganisms. Use of de-esterified corn cobs as carbon source decreased FAE production by 5.5-fold compared to untreated corn cobs even though ferulic acid (FA) was added to the concentration found in alkali-extracts of corn cobs. Production of FAE does not therefore, require FA, however, production is diminished by the removal of esterified FA from the growth substrate. Optimal FAE activity was observed at pH 7 and 50 °C with 68 and 55% activity at pH 8 and pH 9, respectively. The esterase was fully stable at pH 5–8 and up to 40 °C and retained 72 and 40% of its activity after 6 h at pH 9 and pH 10, respectively. After separation by isoelectric focusing electrophoresis, a zymogram indicated one major FAE activity exhibiting pI value of 10.5.

A number of factors affecting production of xylanase, by the thermophilic fungus Sporotrichum thermophileunder solid state fermentation (SSF) were investigated. Initial moisture content and type of carbon source were consecutively optimized. Solid state fermentation in a laboratory horizontal bioreactor using the optimized medium allowed the production of 320 U g−1of carbon source which compared favourably with those reported for other microorganisms. Optimal xylanase activity was observed at pH 5 and 70 °C. Chromogenic (fluorogenic) 4-methylumbelliferyl β-glycoside of xylobiose (MUX2) was used to characterize the xylanase multienzyme component, after separation by isoelectric focusing and native PAGE electrophoresis. The zymograms indicated one major xylanase fraction exhibiting pI and molecular mass values 4 and 90–120 kDa, respectively.