Mixed culture of Saccharomycopsis fibuliger and Zymomonas mobilis on starch-use of oxygen as a regulator

1983 ◽  
Vol 17 (5) ◽  
pp. 269-274 ◽  
Author(s):  
Milan Dost�lek ◽  
Margareta H. H�ggstr�m
1996 ◽  
Vol 45 (5) ◽  
pp. 580-583 ◽  
Author(s):  
C. Abate ◽  
D. Callieri ◽  
Emilio Rodríguez ◽  
Oscar Garro

2019 ◽  
Vol 12 (1) ◽  
pp. 199-210
Author(s):  
Thalisa Yuwa-Amornpitak ◽  
Pa-Nga Yeunyaw

In order to develop a procedure for production bioethanol from cassava pulp, mixed culture of Amylomyces rouxii TISTR 3667 with Zygosaccharomyces pseudorouxii TISTR 5966 or Zymomonas mobilis TISTR 550 and cellulase were evaluated. The parameters such as pH, cellulase, and cassava pulp concentration that influence on the amount of fermentable sugar were optimized by response surface methodology (RSM). Ethanol production was observed and compared to the predicted value that was calculated from the models. The models were fitted to a second-order polynomial equation. They were used to predict ethanol concentration from the use of the mixed culture of A. rouxii TISTR 3667 and Z. mobilis TISTR 550 (G2) that was higher than the amount produced using the mixed culture of A. rouxii TISTR 3667 and Zygosaccharomyces pseudorouxii TISTR 5966 (G1). The following optimum parameters were obtained: pH 6, 20% cassava pulp, and 1% cellulase for G2; and pH 4, 20% cassava pulp, and 0.55% cellulase for G1. The effect of cellulase on ethanol production, a comparative study was conducted in the fermenter by using mixed culture of A. rouxii TISTR 3667 and Z. mobilis TISTR 550. It was showed that more 15% ethanol was gained from 10% cassava pulp with 0.5% cellulase (25 g/l ethanol) compared to the system without cellulase (20 g/l). Mathematically model (equation 4) predicted the ethanol in this system near the actual value of 26.87 g/l. This study indicated that RSM is a powerful tool for optimization fermentation process by using mixed culture including cellulase. Besides these cellulase also reduced viscosity of the cassava medium and enhanced ethanol production. However this process should be more continue to study.


Rumen ciliates still have mysterious secrets and influences in ruminants. This study investigated the effect of transfaunation of pure and mixed cultures of rumen ciliates on physical clinical examination, selected serum parameters and milk profile in defaunated lactating dairy goats. A number of 8 Baladi native breed goats were randomly classified into two groups each one containing 4 goats. Pure culture group was transfaunated with 6 ml of pure culture of Holotricha spp., while mixed culture group was transfaunated with 6 ml of mixed culture of 81.85% Holotricha and 18.15% Ophryoscolex spp. once weekly for three consecutive weeks, after defaunation of both groups using 30 ml of 8% SLS for two consecutive days. Serum and milk samples were collected weekly for three successive weeks to study effect of type of ciliate culture, duration of transfaunation and their interaction. Results revealed that transfaunation of pure and mixed cultures of rumen ciliates had no effect on physical examination with minimal non-significant improvement of calcium, inorganic phosphorous, total protein and globulin in serum of defaunated goats. Transfaunation of pure or mixed cultures of rumen ciliates within three weeks could not improve significantly decreased milk fat % of defaunated goats without any effect on other measured milk profile parameters. It is concluded that further investigations on transfaunation without prior defaunation should be performed using different pure and mixed cultures of rumen ciliates for therapeutic and productive purposes.


1995 ◽  
Vol 31 (9) ◽  
pp. 101-107 ◽  
Author(s):  
Chongchin Polprasert ◽  
Charles N. Haas

Anaerobic reactors were operated in a semi-batch mode and fed with the dual substrates glucose (G) plus acetic acid (Ac) as primary organic sources to study the effect of sulfate on COD oxidation. With glucose, COD removal by methane formation was seriously inhibited, resulting in COD accumulation in the reactor. Although acetic acid can be consumed by some sulfate-reducing species, it was not a major substrate for sulfate reduction, but was largely responsible for methane formation in the anaerobic mixed culture used in this study. With dual substrates, extreme inhibition of methanogenesis did not occur as did with glucose alone. Instead, methanogens were found to work in harmony with acid formers as well as sulfate reducers to oxidise COD. Interestingly, from 12-hour monitoring, increased G/Ac COD ratios decreased COD removal rates as well as biogas production, but resulted in higher sulfate reduction. This suggests that there should be an optimal feed G/Ac COD ratio, for which removal of both organics could be maximised.


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