40 research outputs found
The Productıon And Characterızatıon Of Protease Enzyme From Straıns Of Aspergıllus And Rhızopus
No full textAraştırmada toprak örneklerinden Aspergillus ve Rhizopus izole edilmiştir. Altı Aspergillus niger, 1 Rhizopus oryzae ve Rhizopus sp 2 adlandırılmıştır. Tür tanımak için ITS gen bölgelerinin dizi analizi yapılmıştır. Fungus örneklerinin proteaz enzimi aktivitesi 2 farklı metodla çalışılmıştır. İlk olarak kalsiyum kazeinat agar ve skim milk agar,da proteaz enzim aktivitesi zon çapları tespit edilmiştir. Daha sonra Aspergillus ve Rhizopus suşlarında fermantasyon çalışılmıştır. Fermantasyon sonucunda ham proteaz enzim aktivitesi belirlenmiştir. Daha sonra Anson metodu ile proteaz enzim aktivitesi tespit edilmiştir. Sonuçta Aspergillus niger 2 örneğin proteaz enzim aktivitesi kalsiyum kazeinat agar,da optimum pH 6,6-8,7 arasında en büyük zon çapı oluşturmuştur (10-20 mm). Rhizopus örneklerinin proteaz enzim aktivitesi optimum pH 6,6-8,7 arasında en büyük zon çapı göstermiştir (30-54mm). Fermantasyonun ortamında tuzlu çözelti ve distile su kullanılarak Aspergillus ve Rhizopus suşlarından hazırlanan ham enzimden 50μL, 100μL farklı pH'larda 5, 6, 7, 8 kalsiyum kazeinat agar'da bulunan kuyucuklara ilave edilerek zon çapları ölçülerek proteoliz belirlenmiştir. Aspergillus niger suşlarının zon büyüklüğü pH 5'de 6-14 mm olarak tespit edilmiştir. Rhizopus suşların zon büyüklüğü pH 8.de 2-8 mm arasında belirlenmiştir. Anson metoduna göre proteaz aktivitesi her bir örnek için hesaplanmıştır. Aspergillus niger suşlarının distile su, tuzlu çözelti ve tam buğday unu kullanılarak yapılan fermantasyon sonucunda proteaz aktivitesi 110-265 U/mL aralığında tespit edilmiştir. Rhizopus suşlarının proteaz aktivitesi 167-325 U/mL dir. Daha sonra proteaz ayrılması için Sephadeks G 100 kolonu kullanılmıştır. Aspergillus niger 2 ve Rhizopus oryzae 1 fermantasyonun sonucu (ham enzimi) gel kolonundan geçirilmiştir ve fraksiyonlar toplanmiştir. Fraksiyonların proteaz aktiviteleri Anson metoduna göre belirlenmiş ve jel elektroforezi (SDS-PAGE) yapılmıştır. Aspergillus niger 2 suşlarında üretilen proteazın moleküler ağırlığı ≈ 33 kDa tespit edilmiştir. Rhizopus oryzae 1 fraksiyonların jel elektroforezi (SDS-PAGE) yapılmıştır jel üzerindeki bantlar net olmadığı için üretilen proteazın moleküler ağırlığı tespit edilememiştir. Sonuçta Aspergillus ve Rhizopus suşlarından proteaz enzim aktivitesi farklı metodlarla belirlenmiştir ve enzimler saflaştırılmıştır.In this study, Aspergillus and Rhizopus are isolated from soil samples. Six Aspergillus niger, 1 Rhizopus oryzae and Rhizopus sp 2 were named. In aim to recognize species, pattern analyzes of gene areas of ITS were made. Protease enzyme activities of fungal strains were studied with 2 different methods; firstly in calcium caseinate agar and skim milk agar protease enzyme activities' zone diameters were established, then fermentation in Aspergillus and Rhizopus strains was studied. As a result of fermentation, crude protease enzyme activity was determined. With Anson method, protease enzyme activity was determined. Ultimately, the protease enzyme activity of Aspergillus niger 2 strain created the biggest zone diameter (10-20 mm) in calcium caseinate agar optimum pH 6.6-8.7. The protease enzyme activity of Rhizopus strains' protease enzyme activity generated the biggest zone cap (30-54 mm) with optimum pH between 6.6-8.7. The proteolysis was determined through measuring the diameter's zone resulted from adding 50 μL, 100μL from the crude enzyme that was prepared from Aspergillus and Rhizopus in various pH 5, 6, 7, 8 on the wells of calcium caseinate agar in a fermentation environment, with the usage of salted solution and distillate water. The zone size of Aspergillus niger strain at pH 5 is determined as 6-14 mm. The zone size of Rhizopus strain at pH 8 is determined as (2-8 mm). According to Anson method, protease activity is calculated for every sample. The protease activity in the end of fermentation of Aspergillus niger strains with distillate water, salted solution and whole wheat flour is detected between 110-265 U/mL. The protease activity of Rhizopus strains is between 167-325 U/mL. Then for the separation of protease, Sephadex G 100 colon was used. Aspergillus niger 2 and Rhizopus oryzae 1 are passed on from gel column at the result of fermentation (crude enzyme) and the fractions are collected. Then protease activity of fractions were determined in respect to Anson method, and gel electrophoresis (SDS-PAGE) was performed. The bands on gel were determined. The protease produced in Aspergillus niger 2 strain; its molecular weight was determined as ≈ 33 kDa. Gel electrophoresis (SDS-PAGE) of Rhizopus oryzae 1 fractions was made. However, since the bands on gel cannot be got out well, the produced protease molecular weight was not determined. Eventually, protease enzyme activity from Aspergillus and Rhizopus strains was determined and purified in different methods
Succinic acid production from cheese whey via fermentation by using alginate immobilized Actinobacillus succinogenes
No full text© 2021 Elsevier LtdThe production of succinic acid from cheese whey was studied with immobilized and free cells of Actinobacillus succinogenes. Alginate was used as immobilizing agent, the durability of alginate beads was assessed and improved. Batch fermentations with free cells were conducted using cheese whey, lactose and glucose, highest succinic acid production was achieved with cheese whey (24.9 g L−1) with 35 g L−1 starting lactose concentration. For immobilized batch fermentations, 74.9% yield and 1.09 g L−1 h−1 productivity achieved with cheese whey. Repeated-batch fermentations conducted with whey using the same beads in 5 repeated cycles (144 h) and 0.89 g L−1 h−1 of productivity was achieved. For continuous fermentations with whey and immobilized cells, maximum 0.84 g/g yield was achieved. In this work, it is suggested that immobilizing A. succinogenes with alginate-whey mixture is an effective technique and cheese whey is a valuable resource for the production of succinic acid
Enzymatic hydrolysis of orange bagasse and effect of filtration on lactic acid fermentation
No full textAlong with the general trend of reducing waste in the agro-industrial sector, new methods are sought to utilize side or waste products. With this purpose, we examined the utilization of orange bagasse (OB) for Ca-lactate production via enzymatic hydrolysis and fermentation. The hydrolysis of OB was carried in both dried and fresh forms with cellulolytic and pectinolytic enzymes to obtain a reasonable amount of fermentable sugars for further lactic acid fermentation. A novel industrial approach was studied to increase the hydrolysis yield by reusing the former hydrolysate media. Meanwhile, lactic acid fermentation was performed with optimal OB hydrolysate by Lactobacillus delbrueckii subsp. bulgaricus OZZ4 and Lactobacillus plantarum OZH8. One of the main problems in OB utilization via fermentation was the inhibition observed on microorganisms. It was found that either by drying of the biomass prior to enzymatic hydrolysis or by filtration of the hydrolysate prepared with fresh biomass could be done in order to overcome the inhibitory effects. After treatments, lactic acid with yields around 0.95 g/g and levels of 45 g/L was produced with the fermentation of OB hydrolysate
The simultaneous saccharification and fermentation of malt dust and use in the acidification of mash
No full textIn brewing, the mash or wort is frequently acidified by the addition of lactic acid or the bioacidification of the mash. The present study provides an alternative approach for mash or wort acidification by the simultaneous saccharification and fermentation (SSF) of malt dust. In this method, fermentable carbohydrates released by the enzymatic breakdown of the cellulosic portion of the malt dust are converted to lactic acid by lactic acid bacteria. The effect of temperature, ranging between 45 and 51 degrees C, solid loading of malt dust at 2, 5 and 10% (w/v) on a dry basis, and enzyme loading at 0.65, 2.6 and 6.5 filter paper units (FPU) per gram malt dust on SSF and change in pH in mash acidification were examined. The final pH and lactic acid concentration and final glucose concentration of the SSF media were significantly affected by the temperature of the process (p < 0.05). The highest lactic acid titre (9.7 g/L) and the lowest pH (3.12) were obtained by SSF of 10% (w/v) malt dust at 45 degrees C with 6.5 FPU/g. The pH of the mashing solution [containing 20% (w/v) ground malt] decreased to around 5.4 and 5.2 after adding 1.9 and 2.9% of SSF media with pH 3.39. (C) 2019 The Institute of Brewing & Distillin
Effect of different stresses on trehalose levels in Rhizopus oryzae
No full textRhizopus oryzae accumulates and degrades trehalose in response to environmental stress conditions such as heat, osmotic stress, nitrogen starvation and pH. When heat stress was applied to R. oryzae, the trehalose content of the cells was increased from 0.9 to 4.8 mg/g dw and when the stress was relieved it decreased back to 1.1 mg/g dw. Under osmotic stress and nitrogen starvation, trehalose content was increased by 3.5 and 3 fold, respectively. The decrease in external pH increased trehalose level up to 2.6 mg/g dw from 1.1 mg/g dw. Increased trehalose level decreased back to normal after pH stress was relieved. These results indicate that trehalose accumulates and acts as a stress protectant in R. oryzae
Rheological properties of lactose-free dairy desserts
No full textPeople suffering from lactose intolerance cannot digest milk or lactose-containing foods. Lactose-free diet is essential for them since they do not have the ability to produce lactase to breakdown milk sugar. Physical properties of lactose-free dairy desserts will most probably be different than that of lactose containing ones because of lactose hydrolysis. In this study, it was aimed to analyze the rheological and textural behaviors of different lactose-free dessert formulations containing different gum types and different waxy maize starch and sucrose concentrations. Waxy maize starch was used at concentrations of 0.032gmL(-1), 0.040gmL(-1), and 0.048gmL(-1). In addition to waxy maize starch, guar gum, gum arabic, or -carrageenan at two different concentrations (1.0% w/w and 0.5% w/w) was added. Sucrose was added at concentrations of 0.14gmL(-1) and 0.10gmL(-1) in lactose-free desserts. Power law model was found to be suitable to explain the flow behavior of desserts. The storage and loss modulus of lactose-free desserts were higher than that of lactose-containing desserts. The -Carrageenan was found to be the most effective gum for structure build-up
