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Sublethal effects of low and high molecular weight phthalates were assessed in Unio with a biomarker approach using gills and digestive gland as the main targets of xenobiotic uptake. Diisononyl phthalate, diisodecyl phthalate and dimethyl phthalate were studied for aquatic toxicity to nontarget freshwater mussels. Adult Unio sp. were exposed to sublethal concentrations. After 96 h exposure, total hemocyte counts in hemolymph and malondialdehyde, glutathione, superoxide dismutase, advanced oxidation protein product and protein yields in gill and digestive gland were determined. Total hemocyte counts increased significantly in the dimethyl phthalate and diisodecyl phthalate exposure groups, but decreased in diisononyl phthalate group. Malondialdehyde levels were higher in dimethyl phthalate in both tissues; whereas diisodecyl phthalate caused increase only in gills. Gill glutathione levels were lower in the diisodecyl phthalate while higher in the dimethyl phthalate in both tissues. Superoxide dismutase activities of both tissues decreased in test groups. Advanced oxidation protein product levels were higher in digestive gland than gill and in test groups compared to control. Differences in xenobiotic bioavailability may cause dissimilar responses even though these phthalates have low solubility. Changes in the biomarkers of lipid peroxidation indicate possible initial physical absorption by the mussel.

Peptones are one of the most expensive components of culture media. This study was performed to produce exopolysaccharide (EPS) and mycelial biomass from the edible mushroom Lentinus edodes by using the peptone prepared from waste sheep wool. Wool peptone I (WPI) was prepared by HCl hydrolysis and NaOH neutralization and wool peptone II (WPII) by NaOH hydrolysis and HCl neutralization. The efficiency of wool peptones in EPS and mycelia production was compared with commercial tryptone peptone (TP) and proteose peptone (PP). Protein contents of TP, PP, WPI, and WPII were measured as 83.4, 83.7, 53.6, and 66.7 g/100 g, and their ash contents as 7.4, 10.3, 41.2, and 30.4 g/100 g, respectively. Compared to TP and PP, WPI and WPII were found to be richer in minerals, especially Na and Cl. At the optimal peptone concentration, relatively higher mycelial biomass concentrations were achieved in the presence of commercial peptones. Conversely, wool peptones, especially WPI, were found to be more favorable for EPS synthesis. In WPI, WPII, PP, and TP-based cultures, the maximum concentrations of produced EPS were determined as 0.55, 0.41, 0.35, and 0.21 g/L, respectively. It was determined that EPS samples produced in the presence of wool peptones had lower molecular weight but higher antibacterial activity. This is the first report on usability of wool protein hydrolysate as peptone source for production of mycelial biomass and polysaccharides from mushrooms including L. edodes.

Peptones are one of the most expensive components of microbial culture media. The present study was conducted to test the usability of low-cost sheep wool peptone (SWP) as an organic nitrogen source in the production of six industrially important enzymes (lipase, amylase, tannase, pectinase, cellulase and invertase). SWP was prepared by alkaline hydrolysis and acid neutralization.

The quality of school leaders and teachers is critical to both school development and student achievement. Thus, quality school leaders are needed for teachers to perform their assigned roles and t...

Kernels of loquat (Eriobotrya japonica L.) fruits are rich in protein and starch contents; however, they have no significant application in world. This study was performed to produce pigments from Monascus purpureus ATCC16365 using loquat kernel powder (LKP) as a fermentation substrate and investigate the effect of four mineral salts (CaCl2, KH2PO4, MgSO4, and FeSO4) on pigment production in LKP-based medium. During the experiments, LKP was not subjected to any chemical or enzymatic hydrolysis, and it was tested directly as a substrate in shaking flask and fermenter cultures. It was found that addition of CaCl2 alone decreased red pigment production but did not cause an important change in synthesis of yellow and orange pigments. Supplementation of KH2PO4, MgSO4, or FeSO4 alone decreased the production of yellow pigment but increased the production of red pigments. When three salts (1.0 g/L KH2PO4, 0.3 g/L MgSO4, and 0.03 g/L FeSO4) were added together to the LKP-based medium, more productions of enzymes (protease and amylase) and red pigments were achieved. When experiments were performed in optimized medium (LKP and three mineral salts), maximum concentrations of red, orange, and yellow pigments were determined as 292, 193, and 171 AU/L in flask culture but 327, 241, and 204 AU/L in fermenter culture, respectively. Amylase and protease activities were 93.4 and 52.3 U/L in flask culture but 93.8 and 52.8 U/L in fermenter culture, respectively. This is the first report on the use of LKP as a substrate in production of enzymes and pigments from M. purpureus.

Dut posası (DP), geleneksel bir Türk yiyeceği olan pekmez'in üretiminden sonra ortaya çıkan bir atık maddedir. Bu çalışma, Aspergillus niger MT-4 ile sitrik asit (SA) üretimi için DP’nin substrat olarak kullanılabilirliğini test etmek için gerçekleştirilmiştir. Çalışmada ayrıca, SA üretimini artırmak için bazı kültür koşulları da optimize edilmiştir. MP’nin nem, toplam karbonhidrat, suda-çözünür karbonhidrat, protein, lipid ve kül içerikleri sırasıyla %31,1; 47,1; 1,3; 13,4; 1,8 ve 1,4 olarak belirlenmiştir. Deneyler, üretim besiyerinin 100 ml’sini içeren 250 ml'lik erlenler içerisinde gerçekleştirilmiştir. Hem fungal biyokütle (FB) hem de SA üretimi için optimum DP konsantrasyonu, 120 gr/lt olarak belirlenmiştir. DP bazlı ortama eklenen tüm KH2PO4 konsantrasyonlarının SA üretimini azalttığı fakat FB üretimini artırdığı belirlenmiştir. SA üretimi için MgSO4 ve (NH4)2SO4’ün optimal konsantrasyonları sırasıyla 1 ve 2 gr/lt olarak bulunmuştur. Diğer optimal parametreler, başlangıç pH'sı 7,0 ve inkübasyon süresi 5 gün olarak belirlenmiştir. Optimize edilmiş kültür koşulları altında, üretilen SA miktarı 24,6 gr/lt olarak belirlenmiştir. Beşinci günde, Yp/s; Yp/x ve Yx/s sırasıyla 0,2 gr SA/gr DP; 1,43 gr SA/gr FB ve 0,14 gr FB/gr DP olarak hesaplanmıştır. DP'nin SA dahil mikrobiyal metabolitlerin üretimi için fermentasyon substratı olarak kullanılabilirliği ilk kez bu çalışmada test edilmiştir., Mulberry pomace (MP) is a waste material obtained after the production of pekmez, a traditional Turkish food. This study was performed to test the usability of MP as substrate for citric acid (CA) production by Aspergillus niger MT-4 for the first time. In the study, some culture conditions were also optimized to increase CA production in MP-based medium. Moisture, total carbohydrate, water-soluble carbohydrate, protein, lipid and ash contents of MP were determined as 31.1, 47.1, 1.3, 13.4, 1.8 and 1.4%, respectively. Experiments were carried out in 250 mL flasks containing 100 mL of production medium. Optimal MP concentration for both fungal biomass (FB) and CA production was determined as 120 g/L. All concentrations of KH2PO4 added to MP-based medium were found to decrease CA production but increase FB production. Optimal concentrations of MgSO4 and (NH4)2SO4 for CA production were found as 1 and 2 g/L, respectively. The other optimal parameters were determined as an initial pH of 7.0 and an incubation period of 5 days. Under the optimized culture conditions, the amount of CA produced was determined as 24.6 g/L. On day 5, Yp/s, Yp/x and Yx/s were calculated as 0.2 g CA/g MP, 1.43 g CA/g FB and 0.14 g FB/g MP, respectively.

This study focused on investigating the effect of exogenously applied two quorum sensing molecules (tyrosol and farnesol) on the synthesis of bioactive metabolites (pigments, lactic acid, ethanol, and citric acid) in Monascus purpureus ATCC16365. None of the tested concentrations (62.5, 125, 250, and 500 µl/L) of farnesol affected the synthesis of metabolites as well as cell growth. As with farnesol application, none of the tested concentrations (3.45, 6.9, 13.8, and 27.6 mg/L) of tyrosol caused a significant change in the synthesis of lactic acid and citric acid as well as cell growth. Conversely, all of the tested concentrations of tyrosol increased pigment synthesis but reduced ethanol synthesis, compared with the control. Maximum increases (3.16-, 2.68-, and 2.87-fold increase, respectively) in yellow, orange, and red pigment production were achieved, especially when 6.9-mg/L tyrosol was added to the culture on day 3. On the contrary, 6.9-mg/L tyrosol reduced the content of citrinin by approximately 51.5%. This is the first report on the effect of tyrosol and farnesol on the synthesis of Monascus metabolites. Due to potential properties, such as low price, nonhuman toxicity, promotion of pigment synthesis, and reduction in citrinin synthesis, tyrosol can be used as a novel inducer in the fermentative production of Monascus pigments.

Peptones are widely used as complex fermentation substrate for hyaluronic acid (HA) production; however, use of peptones in HA production reduces commercial competitiveness due to their high price. The present study was conducted to test the feasibility of sheep wool peptone (SWP) (mainly organic nitrogen source) and molasses (mainly carbon source) as cheap substrates for HA production from Streptococcus zooepidemicus ATCC 35246. Six peptones (SWP I–VI) were prepared from sheep wool using different chemical hydrolysis methods. Among them, SWP-VI was determined to be more fovarable for HA production. SWP-VI was compared with commercial tryptone peptone (TP) and protease peptone (PP) in order to evaluate its effectiveness in production of HA, lactic acid (LA) and cell biomass (CB). The protein contents of SWP-VI, TP and PP were determined as 70.6, 83.1 and 83.8 g/100 g, respectively. The best peptone for HA and CB production was SWP-VI, whereas PP was found to be more favourable for LA production. Maximum HA concentrations in SWP-VI, TP and PP media were determined as 3.54, 2.58 and 2.47 g/L, respectively.

Non-sterile culture technique is currently used in some microbial processes. However, there is no study on the use of this technique in the production of microbial lipases and hydrolysis of waste f...

This study was performed to elucidate the effects of two fungal quorum sensing molecules (tyrosol and farnesol) on carotenoid synthesis in the yeast Rhodotorula glutinis and prodigioin synthesis in the bacterium Serratia marcencens. Farnesol or tyrosol was directly added to the flask cultures at the beginning (immediately after inoculation with the preculture) of day 1 or the beginning (49th h) of day 3. The results demonstrated that tyrosol supplementation increased the synthesis of carotenoids but farnesol supplementation increased the synthesis of prodigiosin. It was found that adding farnesol or tyrosol into the culture on day 3 compared to day 1 caused more increments in pigment synthesis. The maximum increase (fivefold) in the synthesis of prodigiosin was achieved with 200 μL/L farnesol supplementation, whereas the maximum increase (2.13 fold) in the synthesis of carotenoids was achieved with 4 mg/L tyrosol supplementation. This is the first report about the effects of fungal quorum sensing molecules (farnesol and tyrosol) on the synthesis of carotenoids and prodigiosin in microorganisms. Due to non-human toxicity and low price and of farnesol and tyrosol, these molecules can be used as novel inducers for large-scale production of microbial pigments.

This study was performed to investigate whether the toxicity of nanoparticles (Ag NPs or TiO2 NPs) affected mitochondrial dynamics (mitochondrial fusion and fission mechanisms) in testicular cells of mice. Animals were assigned into three groups (ten mice per group): control group (distilled water), TiO2 NP group (5 mg/kg per dose), and Ag NP group (5 mg/kg per dose). NPs were administered intravenously (via tail vein) to mice with 3-day intervals. To determine the possible toxic effect of NPs on mitochondrial dynamics, the expression levels of mitochondrial fission (Drp1)- and fusion (Mfn1, Mfn2, OPA1)-related genes were analyzed. The results showed that both Ag NPs and TiO2 NPs entered the testis via the blood–testis barier and accumulated in mouse testis tissue. Experiments showed that administration of Ag NPs neither alters testicular weight and testicular index nor causes significant toxic effect on sperm parameters. RT-PCR analysis demonstrated that Ag NP treatment did not disrupt mitochondrial dynamics in testicular cells. Conversely, administration of TiO2 NPs (anatase

International audience; This paper reports on the systems the InriaFBK Team submitted to the EVALITA 2018-Shared Task on Hate Speech Detection in Italian Twitter and Facebook posts (HaSpeeDe). Our submissions were based on three separate classes of models: a model using a recurrent layer, an ngram-based neural network and a LinearSVC. For the Facebook task and the two cross-domain tasks we used the recurrent model and obtained promising results, especially in the cross-domain setting. For Twitter, we used an ngram-based neural network and the LinearSVC-based model.; Questo articolo descrive i modelli del team InriaFBK per lo Shared Task on Hate Speech Detection in Italian Twitter and Facebook posts (HaSpeeDe) di EVALITA 2018. Tre classi di modelli differenti sono state utilizzate: un model-lo che usa un livello ricorrente, una rete neurale basata su ngrammi e un modello basato su LinearSVC. Per Facebook e i due task cross-domain, sì e scelto un modello ricorrente che ha ottenuto buoni risultati, specialmente per quanto riguarda i task cross-domain. Per Twitter, sono stati utilizzati la rete neurale basata su ngrammi e il modello basato su LinearSVC.

International audience; With the increasing number of interactions, social media users have been vulnerable to intentional aggressive acts and cyberbullying instances. In this paper, first, we carry out a message-level cyber-bullying annotation on an Instagram dataset. Second, we use the correlations on the Instagram dataset annotated with emotion, sentiment and bullying labels. Third, we build a message-level emotion classifier automatically predicting emotion labels for each comment in the Vine bullying dataset. Fourth, we build a session-based bullying classifier with the use of n-grams, emotion, sentiment and concept-level features. For both emotion and bullying classifiers, we use Linear Support Vector Classification. Our results show that "anger" and "negative" labels have a positive correlation with the presence of bullying. Concept-level features, emotion and sentiment features in different levels contribute to the bullying classifier, especially to the bullying class. Our best performing bullying classi-fier with n-grams and concept-level features (e.g., polarity, averaged polarity intensity, moodtags and semantics features) reaches to an F1-score of 0.65 for bullying class and a macro average F1-score of 0.7520.

This work was conducted to examine the effect of locally isolated phosphate-solubilizing bacteria on the growth parameters of chickpea seedling cultivated in pots containing Ca3(PO4)2 (tricalcium phosphate). Among the isolated strains, the highest phosphate-solubilizing activity in the broth medium was observed for the isolate IBP26. Similarly, in the greenhouse study, the same isolate was determined to cause maximum increases in growth parameters (shoot and root length, total biomass, phosphorus, total sugar, and protein contents) of chickpea plants in the presence of Ca3(PO4)2. The isolate IBP26 was identified as Pseudomonas aeruginosa (GenBank accession number: MW092004). Experiments demonstrated that the application of the bacterium alone in the absence of Ca3(PO4)2 or the application of Ca3(PO4)2 alone in the absence of bacterium did not cause significant change in growth parameters of the chickpea plants, and that the desired increases in the growth parameters of these plants could be achieved by the co-application of bacterium and Ca3(PO4)2., Bu çalışma, lokal olarak izole edilmiş fosfat çözücü bakterilerinin, Ca3(PO4)2 (trikalsiyum fosfat) içeren saksılarda yetiştirilen nohut fidelerinin büyüme parametreleri üzerindeki etkisini incelemek için yapılmıştır. İzole edilen suşlar arasında, sıvı kültürde en yüksek fosfat çözündürücü aktivite IBP26 izolatı için gözlenmiştir. Benzer şekilde, sera çalışmasında da, aynı izolatın Ca3(PO4)2 varlığında nohut bitkilerinin büyüme parametrelerinde (sürgün ve kök uzunluğu, biyokütle, fosfor, toplam şeker ve protein içeriği) maksimum artışa neden olduğu belirlenmiştir. IBP26 izolatı Pseudomonas aeruginosa olarak teşhis edilmiştir (GenBank accession number: MW092004). Deneyler, Ca3(PO4)2' nin yokluğunda tek başına bakteri uygulamasının veya bakteri yokluğunda tek başına Ca3(PO4)2 uygulamasının nohut bitkilerinin büyüme parametrelerinde kayda değer değişime neden olmadığını, bu bitkilerinin büyüme parametrelerinde istenilen artışların bakteri ve Ca3(PO4)2' nin birlikte uygulanması sayesinde başarılabileceğini göstermiştir.

International audience; In this paper, we describe two systems for predicting message-level offensive language in German tweets: one discriminates between offensive and not offensive messages, and the second performs a fine-grained classification by recognizing also classes of offense. Both systems are based on the same approach, which builds upon Recurrent Neural Networks used with the following features: word embeddings, emoji embeddings and social-network specific features. The model is able to combine word-level information and tweet-level information in order to perform the classification tasks.

In the textile industry, the jacquard weaving industry is an important branch. Jacquard weaving industry offers rich varieties thanks to computer-aided design system used in pattern design. In parallel to changing fashion trends and consumer perceptions, design of the jacquard fabric is as important as the technology used in design. In researches to determine fabric-designing trends, the cultural perceptions embraced by the society are used. Accordingly, the themes that reflect the experiences and practices of the society are incorporated in the fabric designs. The fact that the designer emphasizes the culture of society and uses it in fabric designs emphasizes the culturally rich design concept. The aim of this research is to emphasize the social phenomena by making new designs inspired by the life stories of Ottoman sultans in jacquard fabric designing. This study was performed by scanning method. The population of the study was the life stories of the Ottoman Sultans, while the sample of the study was the study of the life story of the Ottoman Sultan “Mehmed the Conqueror”. Stories from the life of Fatih Sultan Mehmed were compiled based on the resources available within the scope of the study. Rumeli Fortress and the Map to which the Sultan attached importance, were determined as the theme. Jacquard weaving technique and the fabric patterns are created from in line with the themes and designed in detail from sketching phase to digital design phase and produced as jacquard fabric. In this study, the fabric designs and the images of the fabrics produced are included.

In this study the lipid production potential of the isolated yeast Rhodotorula glutinis TR29 in molasses medium under non-aseptic culture conditions was investigated. Different molasses concentrations and initial pH values were tested to make R. glutinis TR29 cells more dominant population in the medium, thereby preventing undesired microbial contaminants. Contamination could be prevented by selecting the high molasses concentration (20%) and low initial pH (5.0). When these parameters were kept constant, the optimum temperature, additional nitrogen source concentration and incubation time for the lipid production were found to be 25 °C, 4 g/L and 168 h, respectively. Under these culture conditions, the cell mass and lipid concentration were determined as 16.2 and 10.5 g/L, respectively. The lipid content was determined as 64.8%. The main cellular fatty acids of the yeast were oleic (63.5%), politic acid (15.4%), stearic acid (9.1%) and palmiteloic acid (7.2%). The yeast lipids seems to be a promising feedstock for biodiesel production due to a high content of C16 and C18 fatty acids. To our best knowledge, this is the first work on lipid production by yeasts in non-sterile molasses medium.

Deproteinized whey was used as a substrate for the production of lipids by cold-adapted yeast Yarrowia lipolytica B9 under non-sterile culture conditions. Undesired microbial contamination in non-sterile whey medium could be prevented when appropriate culture parameters (inoculum size of 3 mL/100 mL, initial pH of 5.5 and incubation temperature of 15°C) were selected. In contrast to additional nitrogen (ammonium sulfate) and phosphorus (potassium dihydrogen phosphate) sources, additional carbon source (lactose) increased lipid accumulation. Under optimized culture conditions, biomass and lipid concentrations of the yeast were found as 7.4 g/L and 4.29 g/L, respectively. Lipid content was determined as 58% of total cell biomass. Fatty acids of the yeast were oleic acid (18:1), cis-10-heptadecenoic acid (C17:1), palmitoleic acid (16:1) and palmitic acid (16:0). The yeast was found to contain no polyunsaturated fatty acids. The content of C16 and C18 fatty acids was found to be 91.98% of total lipids. Monounsaturated fatty acids accounted for 80.54% of total lipids. Due to rich monounsaturated fatty acid composition, biomass of Y. lipolytica B9 may be used as feedstock for biodiesel production, especially operating in winter conditions. This is the fi rst report on the use of cheese whey as a lipid production substrate for cold-adapted microorganisms including Y. lipolytica yeast. Besides, lipid production potential of Y. lipolytica under non-sterile culture conditions was inves- tigated for the fi rst time in this study. © 2015 Society of Chemical Industry and John Wiley & Sons, Ltd

The present study was performed to produce the protease using free and immobilized cells of locally isolated cold-adapted psychrotolerant yeast Cryptococcus victoriae CA-8. Cell immobilization was performed using sodium alginate as entrapping agent. The best conditions for enzyme production by both free and immobilized cells of the yeast were temperature of 15°C and initial pH of 8.0. The optimal incubation times were 72 and 96 h for immobilized and free cells, respectively. Immobilized cells were reused in 3 successive reaction cycles without any loss in the maximum protease activity. Little decreases in the protease activity were observed in 4 and 5 cycles. Under the optimized conditions, the maximum enzyme activities were determined as 12.1 and 13.5 U/mL for free and immobilized cells, respectively. This is a first attempt on cold-active alkaline protease production by free and/or immobilized cells of yeasts. Besides, the protease activity of the yeast C. victoriae CA-8 was investigated for the...

The aim of the present study was to investigate the potential of isolated fungus Aspergillus flavipes MA-25 to decolorize the textile dye reactive black 5. The fungus was found to be capable of removing the dye from the culture in a wide pH range (not only acidic but also neutral and alkaline pHs) at high salt concentrations (0–50 g/L) and low temperatures (5–35°C) under non-sterile conditions. It was also observed that the fungus could tolerate the dye at high initial concentrations up to 1 g/L. Especially, no significant inhibitory effect on dye removal and fungal growth was seen at the initial dye concentrations of ≤0.4 g/L. At initial dye concentration of 0.2 g/L, complete removal of dye was achieved with 4.71 g/L biomass production in 80 h. The bioadsorption was the principle mechanism involved in dye removal by the fungus. Therefore, it was assumed that the fungus had a great potential for the treatment of dye-bearing textile effluents which are alkaline, cold, and saline.

The present study was performed to produce citric acid (CA) from partly deproteinized cheese whey (DPCW) under non-sterile culture conditions using immobilized cells of the cold-adapted and lactose-positive yeast Yarrowia lipolytica B9. DPCW was prepared using the temperature treatment of 90°C for 15min. Sodium alginate was used as entrapping agent for cell immobilization. Optimum conditions for the maximum CA production (33.3g/L) in non-sterile DPCW medium were the temperature of 20°C, pH 5.5, additional lactose concentration of 20g/L, sodium alginate concentration of 2%, number of 150 beads/100mL and incubation time of 120h. Similarly, maximum citric acid/isocitric acid (CA/ICA) ratio (6.79) could be reached under these optimal conditions. Additional nitrogen and phosphorus sources decreased CA concentration and CA/ICA ratio. Immobilized cells were reused in three continuous reaction cycles without any loss in the maximum CA concentration. The unique combination of low pH and temperature values as well as cell immobilization procedure could prevent undesired microbial contaminants during CA production. This is the first work on CA production by cold-adapted microorganisms under non-sterile culture conditions. Besides, CA production using a lactose-positive strain of the yeast Y. lipolytica was investigated for the first time in the present study.

The objective of this work was to perform production of L-lactic acid from starch-rich waste loquat kernels by newly isolated Rhizopus oryzae MBG-10 fungus. Loquat kernel flour (LKF) was used as substrate (mainly as carbon source). The most favorable conditions for L-lactic acid production were LKF concentration of 80 g/L, CaCO3 concentration of 20 g/L, ammonium sulfate concentration of 3 g/L and incubation time of 108 h. Under these conditions, L-lactic acid and biomass concentrations were 45.4 and 8.2 g/L, respectively, and α-amylase activity was 81.6 U/mL. No significant pH changes were observed in the medium thanks to the buffering capacity of LKF. L-lactic acid could be produced in a single-stage from starch-rich LKF without prior saccharification by the fungus with high amylolytic enzyme activity. This is the first report on use of waste loquat kernels as a lactic acid production substrate.

The aims of the present study were to isolate new yeasts with high extracellular (exo) invertase activity and to investigate the usability of buffer systems as invertase production media by immobilized yeast cells. Among 70 yeast isolates, Cryptococcus laurentii MT-61 had the highest exo-invertase activity. Immobilization of yeast cells was performed using sodium alginate. Higher exo-invertase activity for immobilized cells was achieved in tris-sucrose buffer system (TSBS) compared to sodium acetate buffer system and potassium phosphate buffer system. TSBS was prepared by dissolving 30 g of sucrose in 1 L of tris buffer solution. The optimum pH, temperature, and incubation time for invertase production with immobilized cells were determined as 8.0, 35 °C and 36 h in TSBS, respectively. Under optimized conditions, maximum exo-invertase activity was found to be 28.4 U/mL in sterile and nonsterile TSBS. Immobilized cells could be reused in 14 and 12 successive cycles in sterile and nonsterile TSBS without any loss in the maximum invertase activity, respectively. This is the first report which showed that immobilized microbial cells could be used as a biocatalyst for exo-invertase production in buffer system. As an additional contribution, a new yeast strain with high invertase activity was isolated.