Pretreatment of lignocellulosic biogas substrates by filamentous fungi.

Decomposition of lignocellulosic plant biomass by four filamentous fungi was carried out to facilitate subsequent anaerobic degradation and biogas formation. Agricultural side products, wheat straw and corn stover and forestry energy plant willow chips were selected as plant biomass sources. The substrates were confronted by pure cultures of Penicillium aurantiogriseum (new isolate from rumen), Trichoderma reesei (DSM768), Gilbertella persicaria (SZMC11086) and Rhizomucor miehei (SZMC11005). In addition to total cellulolytic filter paper degradation activity, the production of endoglucanase, cellobiohydrolase, ß-glucosidase enzymes were followed during the pretreatment period, which lasted for 10 days at 37 °C. The products of pretreatments were subsequently tested for mesophilic biogas production in batch reactors. All 4 strains effectively pretreated the lignocellulosic substrates albeit in varying degrees, which was related to the level of the tested hydrolytic enzyme activities. Penicillium aurantiogriseum showed outstanding hydrolytic enzyme production and highest biogas yield from the partially degraded substrates. Corn stover was the best substrate for biomass decomposition and biogas production. Scanning electron microscopy confirmed the deep penetration of fungal hyphae into the lignocellulosic substrate in all cases.

Enhancing biogas production from agroindustrial waste pre-treated with filamentous fungi.

Biogas is the product of anaerobic digestion (AD) of organic waste and is considered to be one of the most valuable natural renewable energy carriers. Plant biomass represents the most abundant eco-friendly energy reservoir on Earth. However, the tenacious and heterogeneous structure of the lignocellulose-rich elements makes it difficult for the involved microbes to digest the recalcitrant substrates. Both the degradation process and the biogas production yield can be enhanced by appropriate pre-treatment of lignocellulosic materials. Filamentous fungi have been known as proficient colonizers of lignocellulosic plant tissues and have been recognized as producers of exceptionally rich and diverse hydrolytic enzymes. We tested Aspergillus nidulans, Trichoderma reesei, Rhizomucor miehei and Gilbertella persicaria filamentous fungal strains for pre-treatment of various agricultural lignocellulosic wastes. During the pre-treatment phase, the ß-glucosidase and endoglucanase activity was measured spectrophotometrically. In the AD step, methane production was monitored by gas chromatography. The preliminary results showed that all the applied strains (Aspergillus nidulans, Trichoderma reesei, Rhizomucor miehei and Gilbertella persicaria) were highly effective in producing both ß-glucosidase and endo-(1,4)-ß-D-glucanase enzymes, which might explain the greatly improved AD results. Pre-treatment with the above-mentioned filamentous fungi positively affected the biogas production, although the effect strongly depended on the selection of the fungal partner for any given biomass substrate. Depending on the used substrate and the pre-treatment strain, overall methane yields were elevated two-fold relative to the controls.

Molecular Characteristics and Treatment of Endothelial Dysfunction in Patients with COPD: A Review Article.

Patients with chronic obstructive pulmonary disease (COPD) show systemic consequences, such as chronic systemic inflammation leading to changes in the airway, airway penetrability, and endothelial function. Endothelial dysfunction is characterized by a list of alterations of endothelium towards reduced vasodilation, proinflammatory state, detachment and apoptosis of endothelial cells, and development of atherosclerosis. COPD-induced endothelial dysfunction is associated with elevated cardiovascular risk. The increment of physical activities such as pulmonary rehabilitation (PR) training have a significant effect on COPD, thus, PR can be an integrative part of COPD treatment. In this narrative review the focus is on the function of endothelial inflammatory mediators [cytokines, chemokines, and cellular proteases] and pulmonary endothelial cells and endothelial dysfunction in COPD as well as the effects of dysfunction of the endothelium may play in COPD-related pulmonary hypertension. The relationship between smoking and endothelial dysfunction is also discussed. The connection between different pulmonary rehabilitation programs, arterial stiffness and pulse wave velocity (PWV) is presented. Endothelial dysfunction is a significant prognostic factor of COPD, which can be characterized by PWV. We discuss future considerations, like training programs, as an important part of the treatment that has a favorable impact on the endothelial function.

The effect of a preparation of minerals, vitamins and trace elements on the cardiac gene expression pattern in male diabetic rats.

BACKGROUND: Diabetic patients have an increased risk of developing cardiovascular diseases, which are the leading cause of death in developed countries. Although multivitamin products are widely used as dietary supplements, the effects of these products have not been investigated in the diabetic heart yet. Therefore, here we investigated if a preparation of different minerals, vitamins, and trace elements (MVT) affects the cardiac gene expression pattern in experimental diabetes. METHODS: Two-day old male Wistar rats were injected with streptozotocin (i.p. 100 mg/kg) or citrate buffer to induce diabetes. From weeks 4 to 12, rats were fed with a vehicle or a MVT preparation. Fasting blood glucose measurement and oral glucose tolerance test were performed at week 12, and then total RNA was isolated from the myocardium and assayed by rat oligonucleotide microarray for 41012 oligonucleotides. RESULTS: Significantly elevated fasting blood glucose concentration and impaired glucose tolerance were markedly improved by MVT-treatment in diabetic rats at week 12. Genes with significantly altered expression due to diabetes include functional clusters related to cardiac hypertrophy (e.g. caspase recruitment domain family, member 9; cytochrome P450, family 26, subfamily B, polypeptide; FXYD domain containing ion transport regulator 3), stress response (e.g. metallothionein 1a; metallothionein 2a; interleukin-6 receptor; heme oxygenase (decycling) 1; and glutathione S-transferase, theta 3), and hormones associated with insulin resistance (e.g. resistin; FK506 binding protein 5; galanin/GMAP prepropeptide). Moreover the expression of some other genes with no definite cardiac function was also changed such as e.g. similar to apolipoprotein L2; brain expressed X-linked 1; prostaglandin b2 synthase (brain). MVT-treatment in diabetic rats showed opposite gene expression changes in the cases of 19 genes associated with diabetic cardiomyopathy. In healthy hearts, MVT-treatment resulted in cardiac gene expression changes mostly related to immune response (e.g. complement factor B; complement component 4a; interferon regulatory factor 7; hepcidin). CONCLUSIONS: MVT-treatment improved diagnostic markers of diabetes. This is the first demonstration that MVT-treatment significantly alters cardiac gene expression profile in both control and diabetic rats. Our results and further studies exploring the mechanistic role of individual genes may contribute to the prevention or diagnosis of cardiac complications in diabetes.

Anti-diabetic effect of a preparation of vitamins, minerals and trace elements in diabetic rats: a gender difference.

BACKGROUND: Although multivitamin products are widely used as dietary supplements to maintain health or as special medical food in certain diseases, the effects of these products were not investigated in diabetes mellitus, a major cardiovascular risk factor. Therefore, here we investigated if a preparation of different minerals, vitamins, and trace elements (MVT) for human use affects the severity of experimental diabetes. METHODS: Two days old neonatal Wistar rats from both genders were injected with 100 mg/kg of streptozotocin or its vehicle to induce diabetes. At week 4, rats were fed with an MVT preparation or vehicle for 8 weeks. Well established diagnostic parameters of diabetes, i.e. fasting blood glucose and oral glucose tolerance test were performed at week 4, 8 and 12. Moreover, serum insulin and blood HbA1c were measured at week 12. RESULTS: An impaired glucose tolerance has been found in streptozotocin-treated rats in both genders at week 4. In males, fasting blood glucose and HbA1c were significantly increased and glucose tolerance and serum insulin was decreased at week 12 in the vehicle-treated diabetic group as compared to the vehicle-treated non-diabetic group. All of the diagnostic parameters of diabetes were significantly improved by MVT treatment in male rats. In females, streptozotocin treatment resulted in a less severe prediabetic-like phenotype as only glucose tolerance and HbA1c were altered by the end of the study in the vehicle-treated diabetic group as compared to the vehicle-treated non-diabetic group. MVT treatment failed to improve the diagnostic parameters of diabetes in female streptozotocin-treated rats. CONCLUSION: This is the first demonstration that MVT significantly attenuates the progression of diabetes in male rats with chronic experimental diabetes. Moreover, we have confirmed that females are less sensitive to STZ-induced diabetes and MVT preparation did not show protection against prediabetic state. This may suggest a gender difference in the pathogenesis of diabetes.

Effect of a multivitamin preparation supplemented with phytosterol on serum lipids and infarct size in rats fed with normal and high cholesterol diet.

BACKGROUND: Although complex multivitamin products are widely used as dietary supplements to maintain health or as special medical food in certain diseases, the effects of these products were not investigated in hyperlipidemia which is a major risk factor for cardiovascular diseases. Therefore, here we investigated if a preparation developed for human use containing different vitamins, minerals and trace elements enriched with phytosterol (VMTP) affects the severity of experimental hyperlipidemia as well as myocardial ischemia/reperfusion injury. METHODS: Male Wistar rats were fed a normal or cholesterol-enriched (2% cholesterol + 0.25% cholate) diet for 12 weeks to induce hyperlipidemia. From week 8, rats in both groups were fed with a VMTP preparation or placebo for 4 weeks. Serum triglyceride and cholesterol levels were measured at week 0, 8 and 12. At week 12, hearts were isolated, perfused according to Langendorff and subjected to a 30-min coronary occlusion followed by 120 min reperfusion to measure infarct size. RESULTS: At week 8, cholesterol-fed rats showed significantly higher serum cholesterol level as compared to normal animals, however, serum triglyceride level did not change. VMTP treatment significantly decreased serum cholesterol level in the hyperlipidemic group by week 12 without affecting triglyceride levels. However, VMTP did not show beneficial effect on infarct size. The inflammatory marker hs-CRP and the antioxidant uric acid were also not significantly different. CONCLUSIONS: This is the first demonstration that treatment of hyperlipidemic subjects with a VMTP preparation reduces serum cholesterol, the major risk factor for cardiovascular disease; however, it does not provide cardioprotection.