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B1 Production (b1 + production)
Kinds of B1 Production Selected AbstractsControl of Aspergillus growth and aflatoxin production using antioxidants at different conditions of water activity and pHJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2003A. Nesci Abstract Aims: The effect of butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), trihydroxybutyrophenone (THB) and propyl paraben (PP) (at concentrations of 1, 10 and 20 mmol l,1) on germination, growth and aflatoxin B1 production by Aspergillus section Flavi was evaluated. Methods and Results: Studies on the percentage of spore germination, elongation rate, growth rate and aflatoxin B1 production were carried out in vitro in relation to water activity (aw) at 0·982, 0·937, 0·809 and 0·747 values. At 0·809 and 0·747aw values none of the isolates was able to germinate. Overall, PP and BHA were the antioxidants most effective at inhibiting germination of both species. In the presence of the lowest concentration of BHA and PP (1 mmol l,1) the conidial germination percentage ranged from 2 to 19% after 15 h of incubation at the highest water activity tested. BHA and PP at 10,20 mmol l,1 completely inhibited conidial germination. The antioxidants more efficient in controlling Aspergillus elongation rate were PP, BHT and BHA. All strains were much more sensitive to all antioxidants tested on the percentage of spore germination and growth rate at 0·937aw. The antioxidants PP and BHA completely inhibited aflatoxin B1 production by all strains when added at 1 mmol l,1. Decreased aflatoxin B1 levels in comparison with the control, were observed with BHT at 1, 10 and 20 mmol,1 with the strain T20 at 0·982aw. In contrast, stimulation was observed with the antioxidant THB at 10 and 20 mmol l,1 at 0·937aw with the strains T20 and T23. The effect of BHA and PP at 1 mmol l,1 on lag phase and growth rate was maintained in the pH range between 6 and 8. At all pH values the inhibitory effect of BHA was higher than PP. No aflatoxin B1 was detected at all pH values. Conclusions: The data show that BHA and PP could be considered as effective fungitoxicants for A. flavus and A. parasiticus. Significance and Impact of the Study: The information obtained show promise for controlling growth and aflatoxin B1 in stored maize. Futher studies should be carried out to examine the potential for antioxidants, such as BHA and PP to effectively control both growth and aflatoxin production. [source] Essential Oil of,Aegle marmelos,as a Safe Plant-Based Antimicrobial Against Postharvest Microbial Infestations and Aflatoxin Contamination of Food CommoditiesJOURNAL OF FOOD SCIENCE, Issue 6 2009Priyanka Singh ABSTRACT:, The essential oil of,Aegle marmelos,L. Correa (Rutaceae) showed strong fungitoxicity against some storage fungi-causing contamination of foodstuffs. The oil also showed efficacy as aflatoxin suppressor at 500 ,L/L as it completely arrested the aflatoxin B1 production by the toxigenic strains (Navjot 4NSt and Saktiman 3NSt) of,Aspergillus flavus,Link. Keeping in view the side effects of synthetic fungicides,,A. marmelos,oil may be recommended as an antimicrobial of plant origin to enhance the shelf life of stored food commodities by controlling the fungal growth as well as aflatoxin secretion. This is the 1st report on aflatoxin B1 inhibitory nature of this oil.,A. marmelos,oil may be recommended as a novel plant-based antimicrobial in food protection over synthetic preservatives, most of which are reported to incite environmental problems because of their nonbiodegradable nature and side effects on mammals. The LD50 of,Aegle,oil was found to be 23659.93 mg/kg body weight in mice (Mus musculus,L.) when administered for acute oral toxicity showing nonmammalian toxicity of the oil. GC-MS analysis of the oil found DL-Limonene to be major component. [source] Impact of environment and interactions of Fusarium verticillioides and Fusarium proliferatum with Aspergillus parasiticus on fumonisin B1 and aflatoxins on maize grainJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2001Sonia Marín Abstract Fusarium verticillioides and F proliferatum isolates were inoculated in mixed cultures with Aspergillus parasiticus on irradiated maize grain at two different inoculum concentrations (2,×,105 and 2,×,102 conidia g,1 dry maize). The treatments were 0.93,0.98 water activity (aw) and 15 and 25,°C for 28 days. A complex relationship was found between aw, temperature, inoculum concentration and the interactions which took place between fumonisin and aflatoxin producers. In general, A parasiticus reduced F verticillioides and F proliferatum populations (by 6,36%) but did not affect fumonisin B1 production by these species. In contrast, while the Fusarium species were not able to decrease A parasiticus populations, they significantly reduced aflatoxin B1 accumulation (by 30,93%). © 2001 Society of Chemical Industry [source] Inhibition of aflatoxin B1 production of Aspergillus flavus, isolated from soybean seeds by certain natural plant productsLETTERS IN APPLIED MICROBIOLOGY, Issue 5 2006Y.L. Krishnamurthy Abstract Aims:, The inhibitory effect of cowdung fumes, Captan, leaf powder of Withania somnifera, Hyptis suaveolens, Eucalyptus citriodora, peel powder of Citrus sinensis, Citrus medica and Punica granatum, neem cake and pongamia cake and spore suspension of Trichoderma harzianum and Aspergillus niger on aflatoxin B1 production by toxigenic strain of Aspergillus flavus isolated from soybean seeds was investigated. Methods and Results:, Soybean seed was treated with different natural products and fungicide captan and was inoculated with toxigenic strain of A. flavus and incubated for different periods. The results showed that all the treatments were effective in controlling aflatoxin B1 production. Captan, neem cake, spore suspension of T. harzianum, A. niger and combination of both reduced the level of aflatoxin B1 to a great extent. Leaf powder of W. somnifera, H. suaveolens, peel powder of C. sinensis, C. medica and pongamia cake also controlled the aflatoxin B1 production. Conclusions:, All the natural product treatments applied were significantly effective in inhibiting aflatoxin B1 production on soybean seeds by A. flavus. Significance and Impact of the Study:, These natural plant products may successfully replace chemical fungicides and provide an alternative method to protect soybean and other agricultural commodities from aflatoxin B1 production by A. flavus. [source] Control of Aspergillus growth and aflatoxin production using natural maize phytochemicals under different conditions of water activityPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 8 2006Andrea V Nesci Abstract The effects of the natural phytochemicals trans -cinnamic acid (CA) and ferulic acid (FA) alone at concentrations of 1,25 mM and in 16 combinations (M: mixtures) on growth and aflatoxin B1 production by Aspergillus flavus Link and A. parasiticus Speare were evaluated. Studies on growth rate and aflatoxin B1 production were carried out in vitro in relation to a water activity aw of 0.999, 0.971, 0.955 and 0.937. Overall, CA at concentrations of 10 and 20 mM and FA,CA mixtures M3 (20 + 5 mM respectively), M8 (25 + 5 mM), M9 (1 + 10 mM), M10 (10 + 10 mM), M11 (20 + 10 mM), M12 (25 + 10 mM), M13 (1 + 20 mM), M14 (10 + 20 mM), M15 (20 + 20 mM) and M16 (25 + 20 mM) were the treatments most effective at inhibiting growth of the four species assayed. All strains were much more sensitive to all natural phytochemicals tested on growth rate at aw = 0.937. CA and the FA,CA mixtures M1 (1 + 1 mM respectively), M4 (25 + 1 mM), M5 (1 + 5 mM), M6 (10 + 1 mM), M7 (20 + 1 mM), M8 (25 + 5 mM), M9 (1 + 10 mM), M10 (10 + 10 mM), M11 (20 + 10 mM), M12 (25 + 10 mM), M13 (1 + 20 mM), M14 (10 + 20 mM), M15 (20 + 20 mM) and M16 (25 + 20 mM) completely inhibited aflatoxin B1 production by all strains at aw = 0.999, 0.971, 0.955 and 0.937. Decreased aflatoxin B1 levels in comparison with the control were observed with FA at 1, 10, 20 and 25 mM with the strains RCM89, RCM108 and RCM38 at aw = 0.971, 0.955 and 0.999 respectively. The data show that CA and FA can be considered as effective fungitoxicants for A. flavus and A. parasiticus in in vitro assay. The information obtained is part of an ongoing study to determine their application at the storage level. Copyright © 2006 Society of Chemical Industry [source] Modeling kinetics of a large-scale fed-batch CHO cell culture by Markov chain Monte Carlo methodBIOTECHNOLOGY PROGRESS, Issue 1 2010Zizhuo Xing Abstract Markov chain Monte Carlo (MCMC) method was applied to model kinetics of a fed-batch Chinese hamster ovary cell culture process in 5,000-L bioreactors. The kinetic model consists of six differential equations, which describe dynamics of viable cell density and concentrations of glucose, glutamine, ammonia, lactate, and the antibody fusion protein B1 (B1). The kinetic model has 18 parameters, six of which were calculated from the cell culture data, whereas the other 12 were estimated from a training data set that comprised of seven cell culture runs using a MCMC method. The model was confirmed in two validation data sets that represented a perturbation of the cell culture condition. The agreement between the predicted and measured values of both validation data sets may indicate high reliability of the model estimates. The kinetic model uniquely incorporated the ammonia removal and the exponential function of B1 protein concentration. The model indicated that ammonia and lactate play critical roles in cell growth and that low concentrations of glucose (0.17 mM) and glutamine (0.09 mM) in the cell culture medium may help reduce ammonia and lactate production. The model demonstrated that 83% of the glucose consumed was used for cell maintenance during the late phase of the cell cultures, whereas the maintenance coefficient for glutamine was negligible. Finally, the kinetic model suggests that it is critical for B1 production to sustain a high number of viable cells. The MCMC methodology may be a useful tool for modeling kinetics of a fed-batch mammalian cell culture process. © 2009 American Institute of Chemical Engineers Biotechnol. 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