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In the last decades, increasing petroleum prices, diminishing oil resources, incessant fluctuations in the oil prices and concerns about global shortage of energy resources have boosted research on production and commercialization of biofuels, e.g., ethanol and butanol, obtained from renewable resources. Besides its application as a fuel, butanol has found numerous industrial applications for the production of plasticizers, lacquers, coatings, detergents, and brake fluids. Biobutanol, together with acetone and ethanol, can be produced in industrial scale by a process called Acetone Butanol Ethanol (ABE) fermentation in anaerobic condition using Clostridium acetobutylicum bacterium. The nature of the carbohydrate and nutrients in the fermentation can affect the ratio of solvents obtained in the ABE fermentation process. In this research, influence of various nutrients and glucose concentrations on the production of butanol by this bacterium was investigated. Results showed that presence of biotin, thiamine, para-amino-benzoic acid, and yeast extract as well as several ions including Mg, Fe, Mn, phosphate, and ammonium acetate in the culture medium is essential for the production of butanol by C. acetobutylicum. Lacks of these compounds in the medium significantly reduced the production of solvents, in spite of the growth of the bacterium .also optimum concentration of glucose was 40g/l for maximum production solvent .In this concentration, maximum solvent concentration was achieved 10.5 g/l and maximum butanol concentration was achieved 6.7g/l with yield of 26.25%.

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A solid state fermentation method was developed for the production of citric acid from date pulp (obtained of date syrup production from the process) by Aspergillus niger PTCC 5010. Poor yield was obtained when potassium ferrocyanide treated date pulp were used as substrate, but methanol at a 3-4% concentration markedly increased the forma-tion of citric acid from the waste. The optimum range of pH and moisture for citric acid production were 3.5-4.5, and 70-80% respectively. This method produced about 168g cit-ric acid per kg of date pulp under optimum conditions. On the basis of reducing sugar consumed, the yield was 87% within eight days.

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 Four varieties of Iranian wheat (Chamran of Ahvaz, Rooshan of Yazd, Zarrine of Aurmieh and Zagross of Ahvaz) were selected. These varieties are selected for high production and their suitable quantity and quality of protein. Phytic acid content in whole flour of these wheat varieties was analyzed. The effects of different leavening agents (2% of yeast, 20 % of sourdough and 1.5% of soda) and various fermentation times (45, 55, 75 min and 65 min for blank) in loaf bread samples (from 70% extraction flour baked at 260 for 20 min) were investigated. Then phytic acid content of these bread samples was compared. The statistical results showed significant differences on phytic acid content for all of varieties (P<0.05). With increasing of fermentation time and using of sourdough as a leavening agent phytic acid content were decreased. The decreasing percent in four mentioned varieties of wheat was 95.5, 95.13, 91.4 and 90.96%, respectively, after 75 min fermentation. Significant differences were observed on interaction between variety, fermentation time and kind of leavening agent (P<0.05). No significant differences were observed between fermentation time and kind of leavening agent.

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In or to evaluation the effects of milk total solids on the growth of starter bacteria during fermentation, pastorizied skim milk concentrated to 4 levels of total solids(14,18,23 and 27%) using a vaccume evaporator. Concentrated milk samples inoculated with a yoghurt starter culture (CH1) and incubated at 43°C for 6 hours. At intervals of 1 hour tow samples removed from the incubator and cultured in BGWA medium. The results showed that increasing milk total solids, increased the lag phase time for both of starter bacteria but increased growth coeficiant. The acidity increased and syneresis decreased with increasing total solids. Increasing total solids to 23% had no significant effect on the flavour scores but increasing of them more than this level decreased the flavour scores significantly. The texture scores increased with increasing of total solids.

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Lovastatin is a potent agent for lowering cholesterol of blood. Since one of the main reasons of mortality in developing countries is cardiovascular disease, which is caused by precipitation of fatty acid (especially cholesterol) in blood vessels; therefore diets containing lovastatin may prevent this type of disease. In this study, Lovastatin, monacolin K or competitive inhibitor of the HMG-CoA reductase (operative enzyme for cholesterol synthesis) was produced by submerged fermentation using Monascus purpureus PTCC5303. Seven chemical and nutritional parameters including maltose, peptone, MgSO4.7H2O, MnSO4.H2O, KH2PO4, thiamin and pH screened using Plackett Burman experimental design for monacolin production. Among different parameters, maltose and MgSO4.7H2O showed significant effect on biomass and monacolin production. The concentration of these agents were optimized using response surface methodology for lovastatin production in the shaker flask. The optimized medium contained 26 g/L maltose, 5 g/L peptone, 0.1 g/L MgSO4.7H2O, MnSO4.H2O 0.5 g/L, 4 g/L KH2PO4, Vitamin B1 0.1 g/L and pH 7. After 10 days of fermentation in the shaker flask with 130 rpm agitation and 30 ºC, we achieved maximum lovastatin production which was 63 mg/l.

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  In this research diacetyl production as a buttery flavor in food industries by Lactic Acid Bacteria (LAB), Lactococcus and Leuconostoc genus was investigated. Batch fermentation process accomplished on MRS (De Man, Rogosa and Sharpe medium) broth medium, medium based on whey powder and based on skim milk powder at different conditions of temperature, agitation speed, glucose as carbon source, tri-sodium citrate as precursor of diacetyl production, inoculum, catalase enzyme, bovin blood as heme protein source and CuCl2. Optimum conditions were determined for achivement of highest production yield.  This research indicated that the optimum fermentation conditions for diacetyl production by LAB were:32º C, 180 rpm, glucose 6 g/l,tri-sodium citrate 5g/l, inoculun 5%, catalase enzyme 6 ml/l, bovin blood 4 g/l, CuCl2 15 mg/l. Finally, for production of diacetyl, a fermenter was used with 10 liter volume, inoculum size 5 % (v/v) with working volume of 6.5 liters. Agitation and temprature were maintained at 180 rpm and 32ºC, respectively. Diacetyl concentration under optimized condition in fermenter was obtained as 945 mg/l.

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In a completely randomized experiment, the effect of Daphnia magna meal on growth performance and carcass composition of rainbow trout (Oncorhynchus mykiss) larvae (body weight 0.538±0.197 g) was evaluated for a period of 60 days. Five diets with the same protein content (crude protein 52.70%) were prepared, including two diets containing fermented daphnia meal T₁ (20%), T₂ (30%), two diets containing raw meal T₃ (20%) and T₄ (30%), and a basal diet without daphnia meal as the control. The bacterial species used for fermenting included five commercial probiotic species. Fermented daphnia meal brought about significantly higher growth and the lowest feed conversion ratios, viz. T₁ (1.27 ± 0.35) and T₂ (1.31 ± 0.46), in comparison with T₃ (1.38 ± 0.37), T₄ (1.41 ± 0.42) and the control (1.84 ± 0.69) (p<0.05). The result of carcass composition analyzes showed that the highest protein percentage (68.23 ± 0.48%) was in T₂ and the highest percentage of fat and energy (11.26 ± 0.50% , 4761.63 ±48.88 Cal g^-1) were in T₄ (p<0.05). The overall results of this experiment indicated that daphnia could be considered as a suitable partial protein source in rainbow trout larval feed.

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Chitin is one of the most abundant renewable polysaccharides in nature that is widely found in the shell of the crustacean, insect cuticle and cell walls of fungi. Due to the unique properties such as biocompatibility, biodegradation and noun toxicity is widely used in various industries. In this study, we used of Banana shrimp, Penaeus merguinsis wastes (particle size 8-10 mm) to extract chitin using microbial fermentation method by Pseudomonas aeruginosa. Demineralization and deproteinization was carried out by incubating shrimp waste inoculated with bacteria at different concentration glucose (0%, 10%, 15% and 20% w/v) and inoculum (10%, 15% and 20% v/v) for 4 day in a shaking incubator (100 rpm) at 30°C. The results showed a direct correlation between the concentration of these parameters and deproteinization and demineralization rate. When studying the effect of these parameters, 20% glucose and 20% of the inoculum was determined as the optimum value, which leads to the production of chitin with a removal of minerals (76%) and protein (86%). Therefore, the microbial fermentation, as an ecofriendly and positive method, can be used to produce a high- quality chitin.

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4 lactobacillus plantarum, strains isolated from natural olive fermentation, was used as a starter culture for aerated olive (Manzanilla green olive) fermentation. Lactic acid bacteria are essential microorganisms in green olive fermentation. Inoculation with a starter culture of lactobacillus plantaru 5 – 7days after brining could standardize olive proccessing. This lactobacillus plantarum must isolated from olive fermentation that is tolerated to high levels of lactic and acetic acids and high level Nacl concentration and also oleuropein 1%. Fermentation took place in 4 glass baril (15 L) with 7 kg of olives and 7 L of brine. Baril 1,baril 2  that were treated with 8% salt and 0.1% acetic acid. Baril 3,baril 4  that were treated with 6% salt and 0.3% acetic acid. Inoculation took place in 5 days after brining for baril 2,4. Aerated condition for barils were supplied with aeration column for approximately 190 days and incubated in 28°C. The samples (olives and brines) were taken at different  fermentation phases. Physical and chemical analyses of olive during the fermentation were including salt, protein, fat, acidity, moisture,ash and in brine olive were including acidity, salt, reducing sugar, pH. In this research, the use of suitable lactobacillus plantarum starter cultures has the potential to improve the microbiological control of process, increase the lactic acid yield and, accordingly, increasing acidity in brine olive and provide the production of natural fermented green olives of consistently high quality. Thus use of inoculation lactic acid bacteria can applied as a new technology during the olive fermentation.

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Kombucha is a non-dairy fermented beverage. Traditional substrate for kombucha production is sweetened black tea. Kombucha culture can also use other carbohydrates such as inulin and oligofructose as a substrate. In this study inulin and oligofructose extracted from Jerusalem artichoke tuber at 0, 2, 4, 6, 8 and 10% were used as substrates for kombucha fermentation. The chemical changes during fermentation period were compared with those occurred during traditional substrate fermentation at the same concentrations. The rate of inulin fermentation by kombucha culture was higher than that of sucrose fermentation. The pH value in kombucha produced with inulin was higher than that of traditional product. Acetic acid and lactic acid measurements using HPLC showed that the acetic and lactic acid contents of traditional product was higher and lower than the kombucha produced with inulin, respectively. Soluble protein content and antioxidant activity was higher in kombucha produced with inulin as a substrate. Thus, using inulin as a substrate for kombucha culture decreases fermentation time and produces a product with high pH.

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One of the traditional products of southern regions of Iran is a fermented product called Mahveh. In this study, effects of garlic extract on chemical, microbial and sensory properties of Mahveh produced from fresh and dried anchovy (Stolephorus indicus), were investigated. The results showed that garlic extract had not significant effects on protein, fat, ash and moisture contents (P>0.05). The lowest values of TVN, TBA and FFA observed in Mahveh produced from the fresh anchovy with garlic extract, that were 321.82 (mg N/100g), 1.58 (mg MA/kg) and 16.95 (% oleic acid), respectively. Mahveh samples had a relatively high acidity, so that pH values of fresh and dried anchovy without and with garlic extract were 5.92, 6.02, 5.93 and 6.09, respectively. Also, antibacterial activity of garlic extract led to decrease of total viable counts in Mahveh produced from fresh and dried anchovy from 3.52 and 4.43 to 2.42 and 3.03 (log cfu/g). This decrease, were significant (P<0/05) for halophilic bacteria, too. Results of the color measurement showed no significant difference in a* and b* values for various treatments (P<0.05), but Mahveh produced from fresh anchovy  was significantly more lightness (L*) in comparison with Mahveh produced from dried anchovy (P<0/05). According to the results of the sensory analysis, the odor was a limiting factor in acceptability of Mahveh. Generally, the results of this study showed that all of four types of Mahveh products made from anchovy were acceptable in view point of the chemical, microbial and sensory quality indices. Moreover, using the garlic extract resulted in improvement of the quality indices of Mahveh.    

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Fermentation process of bread includes primary, middle and final sections. If dough is prepared by the traditional methods and immediately formed, in addition to the more energy consumption, the proper shape of dough will be affected and final product may have compressed texture, less porosity and specific volume and lower flavor and taste scores. Where the three section of fermentation performed, because of equal distribution of gas, more elasticity and formation and aromatic compound, the product has more porosity and taste and flavor. By considering the importance of this issue, the purpose of this study was the effect of primary fermentation time in three levels of 10, 15 and 20 minute, middle fermentation time on three levels of 5, 10 and 15 minute and final fermentation time on three levels of 25, 35 and 45 minute on crumb firmness, porosity, specific volume and sensory properties of Barbari bread. After comparing treatment with fully randomized factorial in p<0.05, the results showed the lowest firmness, the highest porosity and specific volume and the best score in sensory analysis was attribute to samples with primary fermentation time of 30 minute and final fermentation time of 45 minute. As compared to these treatments the greatest effect on improving the quality of Barbari bread was attributing to the sample with middle fermentation time of 10 minute.

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Fermented sausage is a favorite kind of meat-product that has allocated great proportions meat consumption in the world to itself. For the first time in Iran in this study, production of Fermented sausage from muscle tissue of common carp (Cyprinus carpio) was assessed by means of lactic acid bacteria at different incubation temperatures as 15, 25, 35 ˚C To prepare the fish sausage, common carp mince was grounded and mixed with NaCl (3%), glucose (3%) and lactic acid bacteria (5 log CFU/g) and incubated for 48 h. During the incubation of fish sausage, pH, microbiological tests, moisture and protein content, and TVB-N were measured. According to the results, higher temperature stimulated the rapid growth of lactic acid bacteria, resulting in a rapid decline in pH, and consequently suppressed the growth of pseudomonas, Micrococcaceae and Enterobacteriacea. Finally, apart from the TVB-N parameter, the fish sausage in which was fermented at 35 °C showed better results in terms of pH and bacterial load compared to the other incubation temperatures.    

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Quality enhancement and shelf life extension of bread as main meal in Iran is one of the particular importance to people’s health and national economy. So that the purpose of this study were planned to investigation on the effects of emulsifiers (E471, DATEM and  SYTREM) in levels of 0, 0.25, 0.5 and 0.75 % and final fermentation time in 30, 45 and 60 minute on dough rheology (Amylogram and Farinogram) and quantitative and qualitative properties (texture, volume, porosity, crust color and overall acceptability) of composite bread. Porosity and crust color were estimated and analyzed by image J software. The results showed viscosity, dough development time, stability and valometervalue increased by increasing the amount of emulsifierswhereasgelatinationtemperaturewas decreased. AlsoDATEM and SYTREM were more effective as compared tocontrols inwaterabsorption.Experiments showed that the sample with 0.5% DATEM and 45 minutes final fermentation time had the lowest firmness and the highest overall acceptability. On the other hand DATEM, E471 and SYTREM and 30, 45 and 60 min the final fermentation time respectively had the pronounce effect on increasing volume and porosity of the bread samples.  Regarding to color estimation the L* value was increased by addition of emulsifiers especially DATEM to the bread formulation. However the highest L* value was observed in samples 45, 60 and 30 min final fermentation time respectively.  

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In this research, the culture condition improvement on phytase productionby Aspergillus ficuum PTCC 5288 was investigated using submergedfermentation method in 250 ml shake flask. Four factors which influencing phytase production, including carbon source (glucose) in five level (2, 3.5, 5, 6.5 and 8 g/100 mL), nitrogen source (ammonium sulphate) five levels (1, 2, 3, 4 and 5 g/100 mL), phosphor source (wheat bran) five levels (1, 2, 3, 4 and 5 g/100 mL),and fermentation time five levels (48, 120, 192, 264 and 336 hour) were studied. The optimum levels of these significant factors were determined via response surface methodological approach as: 5.23g/100 mL glucose, 1.6 g/100 mL ammonium sulphate, 3.28 g/100 mL glucose wheat branand198.30 hours.The maximum predicted amount of phytase was 39.61 U/mL and the produced amount of phytase under these conditions was 40.21 U/mL, which indicates the efficacy of the model for prediction of phytase production content under different conditions of the medium.  

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In this reasearch, optimal condition on oil and arachidonic acid production by mortierella alpina CBS 754.68 was investigated using response surface methodology. Tow factors which influencing arachidonic acid and oil production; including carbon source (glucose) in five levels (45.8, 50, 60, 70 and 74.14 gl) and nitrogen source (soybean meal) in five levels (7.92, 10, 15, 20 and 22.07 gl) were studied. Arachidonic acid and oil yield varied msignificantly in response to changes in concentration of soybean meal and glucose. The model predicted that, maximum production of AA (that is, up to %56.40) and oil (that is, up to %50.13) could be achieved using the medium containing (glucose 50.35 and soybean 18.30 gl) and (glucose 70 and soybean 10 gl), respectively. In the next stage change the medium composition and biomass during fermentation was investigated in two medium optimized. The results showed that oil and arachidonic acid production significant increase with fungi and storage oil stopped respectively. Phenolic compounds are directly related with cell growth rate and the amount of fungi oil.  

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  Sourdough fermentation by lactic acid bacteria and baker's yeast with acidification of dough and producing lactic acid and acetic acid has significant effects on quality characteristics of bread. Application of liquid sourdough in bakery industry has attracted much attention due to higher dough yield, ease of transition and one-step process in order to achieve desired texture and flavor characteristics in final product. In the research, Response surface liquid methodology was used to optimize sourdough fermentation for increased acidification. Fermentation time (5.3- 18.7 hrs.), temperature (21.6- 38.4 °C), and dough yield (249.6- 350.4) were considered as independent factors according to central composite design and their effects were studied in liquid sourdoughs fermented with Lactobacillus casei subsp casei, Lactobacillus fermentum and Saccharomyces cerevisiae. lactic acid and acetic acid contents and total titrable acidity (TTA) were considered as the main responses. The second order polynomial models satisfactory predicted the effects of variables on acidification properties (R²_adj> 0.80). Statistical analysis showed that all the responses were significantly (P<0.01) correlated to fermentation time and temperature. Increase in fermentation time and temperature was associated with an increase in lactic acid, acetic acid and TTA and fermentation time was the most affecting factor on acidification. Lactic acid was not affected by dough yield but the lower dough yield caused in high acetic acid content and acidity. Based on response surface and contour plots, the optimum conditions for maximum acidification were: fermentation time (21 hrs.), temperature (38°C) and dough yield (DY: 325).  

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 Reduce the quality of traditional breads in recent years related to the type of flour and bread production process is not hidden from anyone. Traditional Iranian breads are prepared from flour with high extraction rate, which contains high amount of minerals, vitamins and fibers, but the presence of high levels of phytic acid prevent absorbing precious minerals in the body and are irreparable harm to the consumers. The purpose of this study was to assess the level of phytic acid in the flour marketed in Ahwaz to bake traditional flat breads, Lavash, Taftoon, Sangak and Barbari, and effect of processing on the content of the primary phytic acid. The results showed that phytic acid of flours was high (91.464 mg/100 gr. flour) and prepared dough and baking bread conditions had not a significant reduction in phytic acid so that the maximum reduction was observed in Barbari bread (33.4 %) and the lowest decrease in Lavash bread (15.79 %), respectively. On the other hand, the mean level of zinc was 592 mg in hundred grams of flour and average of phytic acid mole ratio to zinc was shown 63.67, so bioavailability of zinc was deteriorating. The results indicated that the present baking procedures had not an appreciable effect on reduction of the amount of phytic acid in breads. Due to the high level phytic acid in flours is recommended to considering the amount and type of fertilization in field conditions, baking conditions of bread to be reformed in Ahwaz.