Effect of pH on the Mycelial Growth of Aspergillus niger and Aspergillus flavus

Aspergillus fungus is well-known for causing a number of secondary plant and food rots that can result in the buildup of mycotoxins, despite their significant economic contribution to the fermentation industries. In the past, even the most fundamental influences on the development and inhibition of significant mycotoxigenic fungi were only partially understood. To overcome this issue, an investigation on the impact of pH on the mycelial development of Aspergillus species was conducted. A. niger and A. flavus were inoculated in PDA medium with a range of pH values from 4.0 to 9.0 under in vitro conditions and then cultured for 7 days at room temperature. Results revealed that, the mycelial growth of A. niger and A. flavus was increased with increase in pH level up to 6 and then became static up to pH level 9 and there was no mycelial growth in pH 4. Hence, it was concluded that the use of alkaline compounds as a way of preventing their proliferation and reproductive processes may be used to inhibit the development and spore production of A. niger and A. flavus, which can affect the crops.

Potential of giant reed (Arundo donax L. ) for second generation ethanol production

Background The production of second generation ethanol from lignocellulosic biomasses that have not had their potential fully explored as feedstock is of great importance. Arundo donax is one these biomasses. It is a promising grassy plant to be used as a renewable resource for the production of fuels and chemicals, because of its fast growth rate, ability to grow in different soil types and climatic conditions. The present study evaluated its use as feedstock for the production of second generation ethanol. Results Initially its chemical characterization was carried out, and a protocol for fractioning the biomass through diluted acid pretreatment followed by alkaline pretreatment was developed, providing a solid fraction which was undergone to enzymatic hydrolysis reaching 42 g/L of glucose, obtained in 30 h of enzymatic hydrolysis. This partially delignified material was subjected to a simultaneous saccharification and fermentation (SSF) process, resulting in an ethanol concentration of 39 g/L at 70 h. Conclusions The fermentability of the pretreated biomass was performed successfully through the conception of simultaneous saccharification and fermentation resulting in approximately 75 L of ethanol per ton of cellulose.

The influence of different types of cardioplegic solutions on homeostasis during open heart surgery / Монголын Анагаах Ухаан

BackgroundOpen cardiac surgery in CPB condition has increased dramatically in the recent 5 years. Therefore,multidisciplinary researches are needed on this new technological method. The surgical results andperioperative complications depends on keeping normal level of homeostasis parameters during CPBin the open heart surgery.Materials and MethodsTo study the influence of blood cardioplegic and Del Nido’s solution on homeostasis duringcardiopulmonary bypass, we concluded retrospective sample survey using CPB reports from 535 patients,who underwent cardiac surgery with CPB between 2008 and 2012, in 3rd Hospital’s cardiovascularsurgery department.We calculated average parameters of homeostasis, and studied an aortic cross clamp, CPB time,hemodilution and heart recovery process, on three stages of the surgery.We did comparative study on 21 cases of children, who went under congenital heart disease surgery;using Del Nido’s and blood cardioplegic solution.ResultIn recent 5 years, artery blood indicators were pH=7.45±0.06, paCO2=28.8±5.86 mm.Hg,paO2=398.3±99.33 mm.Hg, BE=-4.15±2.51 mmol/l, HCO¯3=20.57±2.18 mmol/l, Ht=28.15±5%,K+=4.12±0.87 mmol/l and Na+=140±3.22 mmol/l during open cardiac surgery in CPB condition(n=535).In case group (n=21), these indicators were pH=7.33±0.09, paCO2=37.49±12.11 mm.Hg,paO2=465.76±77.54 mm.Hg, BE=-6.2±2.78 mmol/l, HCO¯3=20.44±2.46 mmol/l, Ht=27.38±5.12%,K+=3.65±0.46 mmol/l and Na+=141.22±2.64 mmol/l. In control group (n=21), above results werepH=7.40±0.07, paCO2=28.52±6.34 mm.Hg, paO2=394±88.92 mm.Hg, BE=-5.52±2.37 mmol/l,HCO¯3=18.84±2.39 mmol/l, Ht=27.66±3.52%, K+=3.86±0.66 mmol/l and Na+=141.2±3.22 mmol/l.Conclusions:1. When acid and alkaline balance was normal during CPB, hyperoxia and hypocapnia are appearedthrough gas analysis (p=0.0001). Metabolic acidity and hyperoxia showed up in the case group, whohad used Del Nido’s solution (p=0.0001).2. As the beginning of CPB, patient’s hematocrit is reduced by 10.26% (p=0.0001). The influences ofboth Del-Nido and blood cardioplegic solutions are the same on hemodilutes (p=0.26).3. While blood cardioplegic solution is used, heart is refreshed with 80.3% sinusial rhythm(p=0.0001).4. Aortic cross clamp time and increases repetition of cardioplegic solutions are correlated with cardiacrecovery time positively (r=0.445, p=0.0001, n=520).

The homeostasis during cardiopulmonary bypass / Монголын Анагаах Ухаан

BackgroundOpen cardiac surgery in CPB condition has increased dramatically in the recent 5 years. Therefore,multidisciplinary researches are needed on this new technological method. The surgical results andperioperative complications depends on keeping normal level of homeostasis parameters during CPBin the open heart surgery.Materials and MethodsTo study the parameters of homeostasis during cardiopulmonary bypass, we concluded retrospectivesample survey using CPB reports from 535 patients, who underwent cardiac surgery with CPB between2008 and 2012, in 3rd Hospital’s cardiovascular surgery department.We calculated average parameters of homeostasis, and studied heart recovery process.ResultIn recent 5 years, artery blood indicators were pH=7.45±0.06, paCO2=28.8±5.86 mm.Hg,paO2=398.3±99.33 mm.Hg, BE=-4.15±2.51 mmol/l, HCO¯3=20.57±2.18 mmol/l, Ht=28.15±5%,K+=4.12±0.87 mmol/l and Na+=140±3.22 mmol/l during open cardiac surgery in CPB condition(n=535).80.3% of patients’ heart spontaneously recovered and stabilized with sinus rhythm. 16.4% of them wererecovered with fibrillation while 2.1% of them were recovered with adrenomimetic support and 1.2% ofthem were recovered with strong adrenomimetic support and defibrillation.Conclusions:1. When acid and alkaline balance was normal during CPB, hyperoxia and hypocapnia are appearedthrough gas analysis (p=0.0001).2. While blood cardioplegic solution is used, heart is refreshed with 80.3% sinusial rhythm(p=0.0001).

Acid and Alkaline Hydrolysis Studies of Stevioside and Rebaudioside A.

Hydrolysis studies of the two diterpene glycosides stevioside and rebaudioside A that were isolated from Stevia rebaudiana were performed using acid and alkaline conditions. Acid hydrolysis was carried out using H2SO4 whereas alkaline hydrolysis was performed using NaOH. Using these methods, partial hydrolyzed glycosides of stevioside and rebaudioside A and their sugar residues were identified from the alkaline and acid hydrolysis studies respectively. The structures of the acid and alkaline hydrolysis products were achieved on the basis of extensive NMR and high resolution mass spectral data, and in comparison with the data reported in the literature as well as TLC comparison with their corresponding standard compounds.

Effect of hydroxyurea on subcellular activities of thymidine kinase in developing and aging rat brain.

Hydroxyurea, when injected intraperitoneally at a dose of 1 mg/g body weight, inhibited thymidine kinase activity in developing rat cerebrum (16-day-embryonic) and cerebellum (7-day-postnatal) within a few hours of administration. The inhibition was timedependent and both cytosolic and mitochondrial thymidine kinases were affected. Under the same conditions, the activities of certain other enzymes concerned with DNA metabolism, viz., DNA polymerase, and acid and alkaline DNases were not inhibited. Further, the addition of hydroxyurea in vitro had no effect on the activity of any of the enzymes studied. However, similar treatment given to 2-year-old rat failed to exert any inhibition on either the mitochondrial or soluble thymidine kinase activities in grey and white matter regions of cerebrum and cerebellum. It is inferred that hydroxyurea, apart from its already known effect on ribonucleotide reductase of replicating cells, also affects thymidine kinase.