Usporedno ispitivanje metode odzivnih površina, umjetne neuralne mreže i genetskog algoritma radi optimiranja hidratacije zrna soje

The present investigation deals with the modelling and optimization of soybean hydration for facilitating soybean processing and it focuses on maximization of mass gain, water uptake and protein retention in the bean. Process variables considered for optimization were: soybean to water ratio (1:2.48 obtained with response surface methodology, RSM, and 1.19 obtained with artificial neural network and genetic algorithm, ANN/GA), time (2.0 h using RSM and 8.0 h using ANN/GA) and temperature (40.0 °C using RSM and 45.1 °C using ANN/GA). The findings in this first report on optimization of soaking conditions for soybean hydration employing response surface methodology, hybrid artificial neural network and genetic algorithms reveal a substantially better alternative to the time-consuming soaking process, extensively practiced in industries, in terms of process time economy. Reasonably accurate neural network model (regression coefficient of 0.9443) was obtained based on the experimental data. The optimized set of process conditions was predicted through genetic algorithm, and the effectiveness of the ANN/GA model, validated through experiments, was indicated by significant correlations (R2 and mean squared error (MSE) being 0.9380 and 5.9299, respectively). RSM also resulted in accurate models for predicting percentage mass gain, percentage water uptake and percentage protein retention (R2 and MSE in the range of 0.889–0.9297 and 0.80–4.94, respectively).U radu je modelirana i optimirana hidratacija zrna radi ubrzavanja prerade soje, pri čemu se pokušao ostvariti maksimalni prinos mase, usvajanje vode i retencija proteina. Metodom odzivnih površina te umjetnom neuralnom mrežom i genetskim algoritmom optimirane su sljedeće varijable procesa: omjer zrna soje i vode (optimalni omjer od 1:2,48 i 1:1,19), vrijeme (2 odnosno 8 sati) i temperatura (40 i 45, 1 °C). Tako je pronađena bolja alternativa klasičnom postupku namakanja zrna soje koji se učestalo koristi u industriji, a zahtijeva veliki utrošak vremena. Na osnovi rezultata razvijen je vrlo precizan model neuralne mreže (koeficijent regresije od 0,9443). Genetskim su algoritmom predviđeni optimalni uvjeti prerade, a učinkovitost je modela umjetne neuralne mreže i genetskog algoritma potvrđena ispitivanjem (koeficijent determinacije R2=0,938 i srednja kvadratna pogreška MSE=5,9299). Metodom odzivnih površina također je razvijen točan model procjene prinosa mase, usvajanja vode i retencije proteina (R2=0,8890–0,9297 i MSE=0,80–4,94)

AVERMECTIN PRODUCTION BY SOLID STATE FERMENTATION-A NOVEL APPROACH

Objective: The present study was carried out to evaluate SSF process for the production of avermectin by Streptomyces avermitilis NRRL 8165 using easily available grains, millets and some agricultural by-product.Methods: Various substrates were screened for their ability to support avermectin production. Different parameters to maximize the yield of avermectin by S. avermitilis NRRL 8165 under SSF were optimized by conventional one factor at a time approach and parameters optimized earlier were adopted for the subsequent study.Results: Sorghum seeds used as solid substrate supported maximum growth and total avermectin production (4.6 mg g-1 dry substrate). The optimum values for maximum avermectin production were: moistening medium containing g l-1 KH2PO4 1; MgSO4.7H2O 0.4, inoculum size 20 % (24 h old culture in yeast extract-malt extract dextrose medium) v/w of initial dry substrate, substrate particle size 0.5 to 4 mm, incubation temperature 28 °C, initial moisture level 105%, incubation period of 15 d, 8 % w/w sucrose and 5% w/w soyameal. The avermectin yield with optimized fermentation condition was 5.8 mg g-1 dry substrate which is 1.3 fold higher as compared to non-optimized condition.Conclusion: Avermectin produced by S. avermitilis are widely used as an anthelmintic agent in the medical, veterinary and agricultural applications. In comparison with submerged fermentation, SSF can become an alternative cost-effective method for the production of avermectin. This report demonstrates the feasibility of employing agro-based substrate, that could reduce antibiotics production cost

QUANTIFICATION OF EXEMESTANE ACCUMULATION DURING MICROBIAL BIOCONVERSION BY TLC IMAGE ANALYSIS

Objective: The present study was aimed at developing a rapid, cost effective and accurate method for quantification of exemestane using thin layer chromatography (TLC) separation followed by image analysis and to test it for monitoring the accumulation of exemestane during microbial bioconversion.Methods: After microbial bioconversion and TLC separation of products formed, exemestane was quantified using ImageQuant TL v2003 image analysis software and the results were compared with high performance liquid chromatography (HPLC) analysis.Results: The percentage error between TLC and HPLC analyses was ranged from (-) 5.18 to (+) 5.51. Bacterial strains Arthrobacter simplex IAM 1660, Nocardia sp. MTCC 1534, Pseudomonas putida MTCC 1194 and Rhodococcus rhodochorus MTCC 291 respectively yielded 79.7 (72 h), 63.9 (72 h), 69.8 (96 h) and 83.2 (96 h) mole percent bioconversion of 6-methylene androstenedione to exemestane. Conclusion: Rhodococcus rhodochorus MTCC 291 was found to be the most suitable organism for the bioconversion and may be used to develop an eco-friendly route to replace chemical synthesis that eliminates the use of toxic chemicals and side products

SUBSTRATE CARRIERS FOR C-1(2)-DEHYDROGENATION OF 6-METHYLENE ANDROSTENEDIONE TO EXEMESTANE BY GROWING AND IMMOBILIZED ARTHROBACTER SIMPLEX NCIM 2449

Objective: Permeability of hydrophobic steroid substrates across cell membrane is a critical factor during microbial bioconversion. To increase substrate intake, the feasibility of some organic solvents and emulsifiers as substrate carrier on the bioconversion of 6-methylene androstenedione to exemestane was assessed.Methods: Androstenedione, a commonly available steroid precursor, was chemically converted 6-methylene androstenedione. The time course of exemestane accumulation was estimated after addition of 6-methylene androstenedione dissolved in some organic solvents or dispersed with emulsifiers by growing and immobilized cells of Arthrobacter simplex NCIM 2449 in shake flask cultures.  Results: The use of substrate carriers for addition of 6-methylene androstenedione enhanced the bioconversion several folds. With growing bacterium in triplicate flasks, a peak mol % bioconversion recorded was- ethanol (67.25, 72 h); soybean oil + tween 80 (50.37, 48 h); acetone (38.84, 48 h); soybean oil (38.36, 48 h); lecithin (32.73, 48 h), methanol (32.71, 48 h) and tween 80 (10.37, 48 h). As compared to the growing cells, the bioconversion with Ca-alginate immobilized cells was delayed and peak mol % bioconversion was recorded as ethanol (60.78, 120 h); soybean oil + tween 80 (42.98, 120 h);  methanol (40.50,  72 h);  soybean oil (38.36, 48 h);  acetone (31.18, 72h ) and lecithin (33.67, 120 h); tween 80 (13.87, 120 h).Conclusion: The use of substrate carriers for addition of 6-methylene androstenedione increased the permeability of substrate and may be used to increase the yield of exemestane and reduce incubation time

Bioconversion of 16-dehydropregnenolone Acetate to Exclusively 4-androstene-3,17-dione by Delftia acidovorans MTCC 3363

Delftia acidovorans MTCC 3363 was found to convert 16-dehydropregnenolone acetate (16-DPA) exclusively to 4-androstene-3, 17-dione (AD). Addition of 9α-hydroxylase inhibitors was not required for preventing the accumulation of byproducts. The effect of pH, tempera­ture, substrate concentration, surfactants and carrier solvents on this bioconversion has been studied. 16-DPA was maximally converted in buffered medium at pH 7.0, at temperature 30°C and 0.5 mg ml–1 substrate concentration. Detergent addition and temperature above 35°C had deleterious effect on bioconversion. Dioxan was found to be the best carrier solvent for biotransformation of 16-DPA to AD

Charge Delocalization in Self-Assembled Mixed-Valence Aromatic Cation Radicals

The spontaneous assembly of aromatic cation radicals (D+•) with their neutral counterpart (D) affords dimer cation radicals (D2+•). The intermolecular dimeric cation radicals are readily characterized by the appearance of an intervalence charge-resonance transition in the NIR region of their electronic spectra and by ESR spectroscopy. The X-ray crystal structure analysis and DFT calculations of a representative dimer cation radical (i.e., the octamethylbiphenylene dimer cation radical) have established that a hole (or single positive charge) is completely delocalized over both aromatic moieties. The energetics and the geometrical considerations for the formation of dimer cation radicals is deliberated with the aid of a series of cyclophane-like bichromophoric donors with drastically varied interplanar angles between the cofacially arranged aryl moieties. X-ray crystallography of a number of mixed-valence cation radicals derived from monochromophoric benzenoid donors established that they generally assemble in 1D stacks in the solid state. However, the use of polychromophoric intervalence cation radicals, where a single charge is effectively delocalized among all of the chromophores, can lead to higher-order assemblies with potential applications in long-range charge transport. As a proof of concept, we show that a single charge in the cation radical of a triptycene derivative is evenly distributed on all three benzenoid rings and this triptycene cation radical forms a 2D electronically coupled assembly, as established by X-ray crystallography

Lactate-Mediated Epigenetic Reprogramming Regulates Formation of Human Pancreatic Cancer-Associated Fibroblasts

Even though pancreatic ductal adenocarcinoma (PDAC) is associated with fibrotic stroma, the molecular pathways regulating the formation of cancer associated fibroblasts (CAFs) are not well elucidated. An epigenomic analysis of patient-derived and de-novo generated CAFs demonstrated widespread loss of cytosine methylation that was associated with overexpression of various inflammatory transcripts including CXCR4. Co-culture of neoplastic cells with CAFs led to increased invasiveness that was abrogated by inhibition of CXCR4. Metabolite tracing revealed that lactate produced by neoplastic cells leads to increased production of alpha-ketoglutarate (aKG) within mesenchymal stem cells (MSCs). In turn, aKG mediated activation of the demethylase TET enzyme led to decreased cytosine methylation and increased hydroxymethylation during de novo differentiation of MSCs to CAF. Co-injection of neoplastic cells with TET-deficient MSCs inhibited tumor growth in vivo. Thus, in PDAC, a tumor-mediated lactate flux is associated with widespread epigenomic reprogramming that is seen during CAF formation

Effect of remote ischaemic conditioning on clinical outcomes in patients with acute myocardial infarction (CONDI-2/ERIC-PPCI): a single-blind randomised controlled trial.

BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden