Levilactobacillus brevis AK19B suşu ile ?-aminobütirik asit üretiminin optimizasyonu
Küçük Resim Yok
Tarih
2021
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Bayburt Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Bu çalışmada ekşi mayalı hamurdan izole edilen ve fenotipik olarak tanımlanan Levilactobacillus brevis AK19B suşunun genetik tanımlaması yapılmış ve tekno-fonksiyonel özellikleri incelenerek ?- aminobütirik asit (GABA) üretiminin optimizasyonu gerçekleştirilmiştir. Suş spot kültür yöntemi ile Escherichia coli BC 1402, Salmonella typhimurium RSSK 95091 ve Yersinia enterocolitica ATCC 27729' a karşı iyi bir antimikrobiyal aktivite ve küflere karşı antifungal aktivite göstermiştir. İzolat 25 ?' de çok iyi bir gelişim ve 45 ?' de zayıf gelişim gösterirken 4 ?' de gelişememiştir. pH 5 ve pH 8' de çok iyi gelişme gösteren izolat, %7 NaCI içeren ortamda %10 ve %15 NaCI içeren ortama göre daha iyi gelişim sergilemiştir. L. brevis AK19B suşu termotolerant olmayan, hidrofilik karakterde ve fitaz enzim aktivitesine sahip bir LAB suşu olarak karakterize edilmiştir. Bunun yanı sıra safra tuzu içeren ortamlarda canlılığını belirli bir süre koruyabildiği ve antioksidan aktivite sergilediği tespit edilmiştir. L. brevis AK19B' nin streptomisin, ampisilin, eritromisin, tetrasisin, penisilin, kanamisin ve kloramfenikole karşı direnç göstermediği belirlenmiştir. Çalışmada GABA üretiminde kullanılan monosodyum glutamat konsantrasyonu (MSG), NaCI konsantrasyonu, sıcaklık ve pH bağımsız değişkenlerinin Box-Behnken deneme desenine göre optimizasyonu Design-Expert paket programı kullanılarak gerçekleştirilmiştir. Tasarımın önerdiği deneyler sonucunda bağımsız değişkenlerin yanıtlar üzerine olan etkilerini ifade eden modeller oluşturulmuş ve modellerin uygunluğu varyasyon analizleri (ANOVA) ile değerlendirilmiştir. Elde edilen veriler sonucunda optimum koşullar pH için 4-8, inkübasyon sıcaklığı 25-40 ?, MSG konsantrasyonu 100-300 mM ve NaCl konsantrasyonu için 0-4 mM aralığında değişmektedir. Yapılan denemeler neticesinde bağımsız değişkenlerin GABA üretimi üzerine farklı etkileri olduğu belirlenmiştir. ANOVA ve RSM model istatistiklerinden hareketle quadratik modelin GABA üretimi için daha uygun olduğu ve modelin (p<0,001) önemli olduğunu göstermiştir. Maksimum düzeyde GABA eldesi için pH 5,136, MSG konsantrasyonunun 297, sıcaklığın 26 ve NaCl konsantrasyonun 2,82 olduğu optimum üretim koşullarının uygulandığı bu çalışmada GABA üretiminin 43,85 mg/mL olarak tahminlenmiştir.
In this study, genetic identification of Levilactobacillus brevis AK19B strain isolated from sourdough dough and identified phenotypically was made and ?-aminobutyric acid (GABA) production was optimized by examining its techno-functional properties. The strain showed good antimicrobial activity against Escherichia coli BC 1402, Salmonella typhimurium RSSK 95091 and Yersinia enterocolitica ATCC 27729 and antifungal activity against molds by spot culture method. The isolate grew very well at 25 ? and poorly at 45 ?, but failed at 4 ?. The isolate, which showed very good growth at pH 5 and pH 8, showed better growth in the medium containing 7% NaCl than in the medium containing 10% and 15% NaCl. L. brevis AK19B strain was characterized as a non-thermotolerant, hydrophilic LAB strain with phytase enzyme activity. In addition, it has been determined that it can maintain its vitality for a certain period of time and exhibit antioxidant activity in environments containing bile salt. It was determined that L. brevis AK19B did not show resistance to streptomycin, ampicillin, erythromycin, tetracycin, penicillin, kanamycin and chloramphenicol. In the study, the optimization of the monosodium glutamate concentration (MSG), NaCl concentration, temperature and pH independent variables used in GABA production according to the Box-Behnken experimental design was carried out using the Design-Expert package program. As a result of the experiments suggested by the design, models expressing the effects of independent variables on the responses were created and the suitability of the models was evaluated by analysis of variation (ANOVA). As a result of the data obtained, optimum conditions range from 4-8 for pH, incubation temperature 25-40 ?, MSG concentration 100-300 mM and for NaCl concentration 0-4 mM. As a result of the experiments, it was determined that the independent variables had different effects on GABA production. Based on the ANOVA and RSM model statistics, it has been shown that the quadratic model is more suitable for GABA production and the model (p<0.001) is important. For maximum GABA production, optimum production conditions of pH 5.136, MSG concentration of 297, temperature of 26 and NaCl concentration of 2.82 were applied, and GABA production was estimated as 43.85 mg/mL.
In this study, genetic identification of Levilactobacillus brevis AK19B strain isolated from sourdough dough and identified phenotypically was made and ?-aminobutyric acid (GABA) production was optimized by examining its techno-functional properties. The strain showed good antimicrobial activity against Escherichia coli BC 1402, Salmonella typhimurium RSSK 95091 and Yersinia enterocolitica ATCC 27729 and antifungal activity against molds by spot culture method. The isolate grew very well at 25 ? and poorly at 45 ?, but failed at 4 ?. The isolate, which showed very good growth at pH 5 and pH 8, showed better growth in the medium containing 7% NaCl than in the medium containing 10% and 15% NaCl. L. brevis AK19B strain was characterized as a non-thermotolerant, hydrophilic LAB strain with phytase enzyme activity. In addition, it has been determined that it can maintain its vitality for a certain period of time and exhibit antioxidant activity in environments containing bile salt. It was determined that L. brevis AK19B did not show resistance to streptomycin, ampicillin, erythromycin, tetracycin, penicillin, kanamycin and chloramphenicol. In the study, the optimization of the monosodium glutamate concentration (MSG), NaCl concentration, temperature and pH independent variables used in GABA production according to the Box-Behnken experimental design was carried out using the Design-Expert package program. As a result of the experiments suggested by the design, models expressing the effects of independent variables on the responses were created and the suitability of the models was evaluated by analysis of variation (ANOVA). As a result of the data obtained, optimum conditions range from 4-8 for pH, incubation temperature 25-40 ?, MSG concentration 100-300 mM and for NaCl concentration 0-4 mM. As a result of the experiments, it was determined that the independent variables had different effects on GABA production. Based on the ANOVA and RSM model statistics, it has been shown that the quadratic model is more suitable for GABA production and the model (p<0.001) is important. For maximum GABA production, optimum production conditions of pH 5.136, MSG concentration of 297, temperature of 26 and NaCl concentration of 2.82 were applied, and GABA production was estimated as 43.85 mg/mL.
Açıklama
Lisansüstü Eğitim Enstitüsü, Gıda Mühendisliği Ana Bilim Dalı
Anahtar Kelimeler
Gıda Mühendisliği, Food Engineering
