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The renewable lignocellulosic biomass is a sustainable feedstock for the production of bioethanol, which shows the potential to replace fossil fuels. Due to the recalcitrant structure of plant cell wall made of cellulose, hemicellulose, and lignin, the biomass conversion process requires the use of efficient pretreatment process before enzymatic hydrolysis and fermentation to degrade the crystallinity of cellulose fibres and to remove lignin from biomass. Proper pretreatment techniques, economical production of cellulolytic enzymes, and effective fermentation of glucose and xylose in the presence of inhibitors are key challenges for the viable production of bioethanol. Although new strains capable of fermenting xylose are being designed, they are often not resistant to toxic compounds in hydrolysates. This paper provides an in-depth review of lignocellulosic bioethanol production via biochemical route, focusing on the most widely used pretreatment technologies and key operational conditions of enzymatic hydrolysis and fermentation considering sugar/ethanol yields. In addition, this review examines the relevant detoxification strategies for the removal of toxic substances and the importance of immobilization. The review also indicates potential usage of engineered microorganisms to improve glucose and xylose fermentation, cellulolytic enzymes production, and response to stress conditions.

Gut colonization by antibiotic-resistant bacteria may underlie hard-to-treat systemic infections. There is also accumulating evidence on the immunomodulatory function of gut microbiota after allogeneic stem cell transplantation (alloSCT) and its impact on graft-versus-host disease (GVHD). We investigated the epidemiology and clinical impact of gut colonization after alloSCT and retrospectively analyzed data on 107 alloSCTs performed at a single transplant center. Pretransplant microbiology screening identified colonization in 31% of cases. Colonization had a negative impact on overall survival after alloSCT in univariate (34% versus 74% at 24 months, P

This research shows the effect of dilute acid pretreatment with various sulfuric acid concentrations (0.5-2.0% [wt/vol]) on enzymatic saccharification and fermentation yield of rye straw. After pretreatment, solids of rye straw were suspended in Na citrate buffer or post-pretreatment liquids (prehydrolysates) containing sugars liberated after hemicellulose hydrolysis. Saccharification was conducted using enzymes dosage of 15 or 25 FPU/g cellulose. Cellulose saccharification rate after rye straw pretreatment was enhanced by performing enzymatic hydrolysis in sodium citrate buffer in comparison with hemicellulose prehydrolysate. The maximum cellulose saccharification rate (69%) was reached in sodium citrate buffer (biomass pretreated with 2.0% [wt/vol] H2 SO4 ). Lignocellulosic complex of rye straw after pretreatment was subjected to separate hydrolysis and fermentation (SHF) or separate hydrolysis and co-fermentation (SHCF). The SHF processes conducted in the sodium citrate buffer using monoculture of Saccharomyces cerevisiae (Ethanol Red) were more efficient compared to hemicellulose prehydrolysate in respect with ethanol yields. Maximum fermentation efficiency of SHF processes obtained after rye straw pretreatment at 1.5% [wt/vol] H2 SO4 and saccharification using enzymes dosage of 25 FPU/g in sodium citrate buffer, achieving 40.6% of theoretical yield. However, SHCF process using cocultures of pentose-fermenting yeast, after pretreatment of raw material at 1.5% [wt/vol] H2 SO4 and hydrolysis using enzymes dosage of 25 FPU/g, resulted in the highest ethanol yield among studied methods, achieving 9.4 g/L of ethanol, corresponding to 55% of theoretical yield.

Zbog klimatskih promjena i iscrpljivanja zaliha fosilnih goriva postoji velika potreba za pronalaskom alternative nafti kao pogonskom gorivu. U ovom je radu dan pregled proizvodnje druge generacije bioetanola, koja se od prve generacije te narednih generacija razlikuje u iskorištavanju lignoceluloze kao sirovine. Opisani su sastojci lignocelulozne biomase, kao što su celuloza, hemiceluloza i lignin, te koraci u tehnološkom postupku, uključujući prethodnu obradu, enzimsku hidrolizu, fermentaciju, destilaciju i dehidraciju. Prethodnom obradom povećala se površina ugljikohidrata potrebna za enzimsku saharifikaciju, te se smanjilo nastajanje inhibitora. Enzimskom se hidrolizom oslobađaju fermentabilni šećeri, koji se djelovanjem mikroorganizama prevode u etanol. Hidrolizati dobiveni prethodnom obradom i enzimskom hidrolizom sadržavaju različite šećere, a najviše glukoze i ksiloze. Za fermentaciju oba šećera neophodni su genetički modificiranimikroorganizmi. Suvišak štetnih inhibitora poput slabih organskih kiselina, derivata furana i fenolnih spojeva može se ukloniti iz hidrolizata detoksikacijom prije fermentacije. Za učinkovitu provedbu saharifikacije potrebno je omogućiti istodobnu aktivnost egzogenih hemicelulaza i enzima što razgrađuju celulozu. Konvencionalni sojevi destilerijskog kvasca ne mogu fermentirati pentozu u etanol, a samo nekoliko prirodnih mikroorganizama, uključujući sojeve kvasaca Candida shehatae, Pichia (Scheffersomyces) stipites i Pachysolen tannophilus, imaju sposobnost razgradnje ksiloze u etanol. Enzimska hidroliza i fermentacija mogu se provesti na nekoliko načina, uključujući zasebnu saharifikaciju i fermentaciju, te simultanu saharifikaciju i fermentaciju. Mikroorganizmi koji fermentiraju pentozu mogu se proizvesti genetičkim inženjerstvom, i to umetanjem gena za kodiranje ksiloze u metabolizam odabranog mikroorganizma radi optimiranja iskorištenja ksiloze iz hidrolizata., In the context of climate change and the depletion of fossil fuels, there is a great need for alternatives to petroleum in the transport sector. This review provides an overview of the production of second generation bioethanol, which is distinguished from the first generation and subsequent generations of biofuels by its use of lignocellulosic biomass as raw material. The structural components of the lignocellulosic biomass such as cellulose, hemicellulose and lignin, are presented along with technological unit steps including pretreatment, enzymatic hydrolysis, fermentation, distillation and dehydration. The purpose of the pretreatment step is to increase the surface area of carbohydrate available for enzymatic saccharification, while minimizing the content of inhibitors. Performing the enzymatic hydrolysis releases fermentable sugars, which are converted by microbial catalysts into ethanol. The hydrolysates obtained after the pretreatment and enzymatic hydrolysis contain a wide spectrum of sugars, predominantly glucose and xylose. Genetically engineered microorganisms are therefore needed to carry out co-fermentation. The excess of harmful inhibitors in the hydrolysate, such as weak organic acids, furan derivatives and phenol components, can be removed by detoxification before fermentation. Effective saccharification further requires using exogenous hemicellulases and cellulolytic enzymes. Conventional species of distiller’s yeast are unable to ferment pentoses into ethanol, and only a very few natural microorganisms, including yeast species like Candida shehatae, Pichia (Scheffersomyces) stipitis, and Pachysolen tannophilus, metabolize xylose to ethanol. Enzymatic hydrolysis and fermentation can be performed in a number of ways: by separate saccharification and fermentation, simultaneous saccharification and fermentation or consolidated bioprocessing. Pentose-fermenting microorganisms can be obtained through genetic engineering, by introducing xylose-encoding genes into metabolism of a selected microorganism to optimize its use of xylose accumulated in the hydrolysate.

Diarrhea constitutes a frequent and often debilitating complication of allogeneic hematopoietic cell transplantation (alloHCT). Especially when accompanied by jaundice, skin rash, and symptoms of the upper gastrointestinal tract, diarrhea strongly suggests emergence of acute graft-versus-host disease (GvHD), which is a serious immune complication of the procedure, with possible fatal consequences. However, especially when diarrhea occurs as an isolated symptom, the other causes must be excluded before initiation of GvHD treatment with immune-suppressive drugs. In this article, a broad overview of the literature of different causes of diarrhea in the setting of alloHCT is provided, revealing causes and presentations different from those observed in the general population. We discuss gastrointestinal GvHD with a special focus on biomarkers, but also uncover underlying infectious: viral, bacterial, and parasitic as well as toxic causes of diarrhea. Finally, we suggest a practical algorithm of approach to patients with diarrhea after alloHCT, which may help to establish a proper diagnosis and initiate a causative treatment.

Background Patients with blood disorders colonized with antibiotic-resistant bacteria (ARB) are prone to systemic infections that are difficult to treat. Reintroduction of commensal bacteria in a murine model of enterococcal colonization of the gut can lead to eradication of enterococci. We hypothesized that fecal microbiota transplantation (FMT) could be used to eradicate ARB in humans. Methods Participants colonized with ARB were treated with intraduodenal FMT according to a prospective protocol (NCT02461199). The primary endpoint was complete ARB decolonization at 1 month after FMT. Secondary endpoints included safety assessment and partial ARB decolonization. Microbiome sequencing was performed to investigate the influence of microbial composition of the transplanted material on the outcome of FMT. Results Twenty-five FMTs were performed in 20 participants (including 40% who had neutropenia) who were colonized by a median of 2 (range, 1-4) strains of ARB. The primary endpoint was reached in 15/25 (60%) of the FMTs and more frequently in cases in which there was no periprocedural use of antibiotics (79% vs 36%, P < .05). Among participants, 15/20 (75%) experienced complete ARB decolonization. There were no severe adverse events, and partial ARB decolonization was observed in 20/25 (80%) of the FMTs. The microbiota composition analysis revealed higher abundance of Barnesiella spp., Bacteroides, and Butyricimonas and greater bacterial richness in the fecal material, resulting in eradication of Klebsiella pneumoniae compared with nonresponders. Conclusions FMT in patients with blood disorders is safe and promotes eradication of ARB from the gastrointestinal tract. Clinical Trials Registration NCT02461199.

Type 1 diabetes mellitus belongs to the diseases most often appearing in the developmental age. The incidence of this disease is characterized by the constant dynamic increase.The purpose of this work was to estimate the value and the dynamics of the incidence of type 1 diabetes mellitus in children from Bydgoszcz region and its analysis according to sex, age, place of residence and season of diabetes diagnosis.In the period from 1997 to 2002 type 1 diabetes mellitus was recognized in 161 children (80 boys and 81 girls) up to the 14th age of life in separate age groups: 0-4 years: 20; 5-9 years: 68; 10-14 years: 73. The incidence was estimated with the help of an index which was the number of new-recognized type 1 diabetes mellitus cases during one year in the population of 100 000. The number of population was taken from Demographic Yearbook of Provincial Office.The average annual index of the incidence for the six-year period being analyzed was 13.55, it balanced in the following years from 9.44 (1997) up to 15.28 (2002). The highest index of incidence (16.34) was noted in 2000 year. The increase in number of falling ill was observed in groups: 5-9 years old and 10-14 years old. Rarely the diabetes was recognized in the youngest children. The diabetes was almost twice more often recognized in children living in towns (16.30) in comparison with those living in the country (8.84). Revelation of the diabetes takes place mainly in the autumn and winter months. The least number of falling ill was noted in June. The seasonal incidence was observed mainly in children over 5 years.1. The index of the type 1 diabetes mellitus incidence among 0-14 year old children was 13.55. 2. During the years 1997-2002 this index increased from 9.44 to 15.28. 3. The diabetes was almost twice more often recognized in children living in towns. 4. The number of becoming ill depends on the season of the year.

The aim of study was analysis of type 1 diabetes mellitus symptoms at admission to hospital.Thirty-seven patients (21 boys and 16 girls) aged from 1.87 to 19.75 years with admitting diagnosis of diabetes mellitus in the year 2000 (the greatest count of patients) were analyzed. In statistical analysis the t-Student test was used.The most frequent symptoms was dry sensation in mouth 95% of patients, polydypsia 84%, polyuria 65%, lose on weight 49%, nocturia - 27% children. Nine children were admitted to hospital in serious ketoacidosis. Twenty-eight children were admitted to hospital in good condition. There were not essential abnormalities in the blood. Observation period in poor general condition group was shortest for children living in the country - on the average 9 days versus patient from cities - 18 days. There was not difference in good general condition group. HbA1c, pH, HCO3 values were statistically significant. In 3 cases diagnosis of diabetes mellitus was preceded by an eliminating others diseases. In 2 children hyperglycemia was established by chance.1) Ketoacidosis symptoms and serious state was observed in 1/4 patient admitted to hospital. 2) It is necessary to take diabetes mellitus into consideration more often in differentiation in pediatric practice. 3) Short observation period of severe ketoacidosis symptoms in-patient from country origin and dismiss preliminary diagnosis may indicate insufficient healthy education - especially in the field of diabetes mellitus. 4) Less than half of patients report to family doctors.

Colonization of the gastrointestinal tract with multidrug-resistant (MDR) bacteria is a consequence of gut dysbiosis. We describe the successful utilization of fecal microbiota transplantation to inhibit Klebsiella pneumoniae MBL(+) and Escherichia coli ESBL(+) gut colonization in the immunocompromised host as a novel tool in the battle against MDR microorganisms. ClinicalTrials.gov identifier NCT02461199.