Background: Amylases are used in several industrial and biotechnological sectors, including those producing textiles, detergents, paper and bakery products. Objective: This study aimed to purify an industrially important α-amylase from Bacillus sp. For this purpose, a single and rapid α-amylase purification was performed using the starch affinity method. Methods: Characterization of the purified enzyme was determined by investigating temperature, pH stability, detergents, and metal ions. Results: The purification coefficient of 29.8-fold with a yield of 9.2% was found. The molecular weight of the purified α-amylase was determined to be 53 kDa by SDS-PAGE, and thermostability was confirmed with 100% activity at 30ºC and 40ºC after 1 h. The purified enzyme was stable over a wide range of pH values, with optimum activity at pH 6.0, 7.0 and 8.0 after 2 h. The study also investigated the effects of the metal ions and detergents on the purified amylase and found that Mg2+ and Ca2+ ions were the activators of the enzyme, while Zn²⁺, Co²⁺ and Na+ ions decreased the activity. Furthermore, Hg2+ indicated complete inhibition of amylase activity. The detergents Triton X-100 and Tween 20 increased the α-amylase activity, while sodium dodecyl sulfate inhibited the activity. Conclusion: The purified α-amylase obtained from Bacillus sp. is considered to be environmentally friendly, can be processed in a short time, and has a low cost.

Amilazlar; bitkiler, hayvanlar ve mikroorganizmalar tarafından üretilen nişastayı parçalayan enzimlerdir. Mikroorganizmalar tarafından üretilen amilazlar; eczacılık, gıda, deterjan, tekstil, kağıt ve kağıt hamuru endüstrisi gibi çok çeşitli endüstriyel uygulamalarda kullanılabilme özelliğine sahiptir. Bununla birlikte, amilaz üreten mikroorganizmaların izolasyonunda hala kısıtlamalar vardır. Işgın bitkisi tıp başta olmak üzere birçok alanda kullanılan önemli bir bitkidir. Bu çalışmanın amacı yararlı ışgın bitkisinden bakterinin izolasyonu gerçekleştirerek biyoteknolojik öneme sahip olan amilazın elde edilmesidir. Bakteri izolasyonu dilüsyon tekniği kullanılarak yapıldı. Bitki kök kısmında bulunan toprak alınarak seyreltme işlemi gerçekleştirildi. İzolasyon sonrası morfolojik, fizyolojik ve biyokimyasal testler yapıldı. Mikroorganizmanın tür teşhisi için 16 S rRNA analizi gerçekleştirildi. Bakteri sekans analiz sonucunda 864 baz çiftine sahip Bacillus atrophaeus olduğu tespit edildi. Tanımlamada etkili olan biyokimyasal testler sonucunda bakterinin gram pozitif (+), basil ve hareketsiz olduğu belirlendi. Katalaz, hemoliz ve glikoz un pozitif (+) sonuç verdiği; oksidaz, H 2 S ve indol gibi biyokimyasal testlerin negatif (-) olduğu tespit edildi. Öncelikle bakteri üremesinin optimizasyonu sağlandı. Zaman, sıcaklık ve pH gibi bakteri üremesine doğrudan etki eden önemli parametreler çalışıldı. Optimum bakteri üretimi sırasıyla 72.saat, 30 o C ve pH 6.0 belirlendi. Güçlü amilaz üretimini belirlemek amacıyla nişastalı katı besi yerinde bakteriler üretildi. İnkübasyon sonrası lügol çözeltisi kullanılarak mikroorganizmanın amilaz ürettiği tespit edildi. Amilaz sentezlendiği belirlenen bakterinin optimal üretim koşulları tespit edildi. Bacillus atrophaeus ’tan α-amilaz’ın maksimum üretim koşulları 36. saat, 35 o C ve pH 6.0 olduğu görüldü. Optimum şartlarda üretilen bakterinin süpernatant kısmı kullanılarak enzim karakterizasyonu gerçekleştirildi. Enzim sıcaklık ve pH’sı sırasıyla 40 o C ve pH 6.0 da maksimum aktivite gösterdiği tespit edildi. Bu tespitler sonucunda istenilen bakteri elde edildi. Tanımlanan ve amilaz ürettiği tespit edilen bakteri, farklı biyoteknolojik alanlarda kullanılma özelliğine sahip olduğu belirlendi.

The alpha-amylase is used extensively in many different industrial sectors and is renowned for modifying starch by rupturing 1-4 glycosidic bands. Depending on the intrinsic properties of the microorganism, several alpha-amylases with thermostable and halotolerant properties are expressed. In the current study, the bacteria were isolated from Ergani Makam Mountain. Identification and optimization of the isolated bacteria were performed. As a result of the 16S rRNA analysis, physiological, morphological and biochemical analyis were carried out for the identification of the isolated microorganism and consequently the bacterium was defined as Bacillus megaterium MD-1. Following its identification, α-Amylase, was isolated from B. megaterium. Optimal conditions for bacteria and enzyme production were determined as 48 hours, 35°C and pH 7.0. Maximum enzyme activity was optained at 40°C and pH 8.0. The effects of various carbon and nitrogen sources on enzyme production were investigated by adding to the nutrient medium. Compared to the control regarding enzyme production, it was determined that carbon sources, particularly sucrose, fructose and lactose inhibited enzyme production by 75%, no change on the other hand was observed in glucose, starch and galactose. It was also observed that urea and sodium nitrate from nitrogen sources had an inhibitory effect on enzyme production whereas other nitrogen sources did not. The highest amylase production among nitrogen sources was obtained with peptone addition. In our study, it was determined that an increase in amylase activity could be achieved by using the optimum values of physical parameters.

Wastewater from textile industries that contain methylene blue poses a serious environmental problem due to its stability and toxicity. In the current study, calf starter feed (CSF), goat feed (GF), and lamb grower feed (LGF) were investigated as potential adsorbents for methylene blue removal from aqueous solutions. For structure and surface analyses of the adsorbents, EDX analysis was performed with FTIR and SEM, respectively. Parameters such as pH, adsorbent dosage, dye concentration, and time were varied, and optimum pH values of 6.0 and 7.0 were obtained for CSF and both GF and LGF, respectively. It was noted that adsorption increased with adsorbent concentration; conversely, it decreased with an increase in initial dye concentration. Among all the isotherms examined, the Langmuir isotherm yielded the best correlation, with R² > 0.98. The maximum adsorption capacity was found to be 12.4, 11.5, and 11.01 mg g⁻¹ for CSF, GF, and LGF, respectively. Kinetic analysis showed that the pseudo-second-order model provided the best fit to the experimental data, suggesting that adsorption may involve surface interaction processes. The findings demonstrate that commercial animal feeds can serve as alternative adsorbents for methylene blue removal and provide the first evidence of their potential application in wastewater treatment.