The ability of activated carbon which was produced by chemical activation using zinc chloride from tea industry wastes (TIWAC) to adsorb phenol molecules from aqueous solution was tested by equilibrium, kinetic, and thermodynamic parameters. Phenol adsorption on TIWAC took place with a high yield at pH values in the range 4 to 8. The optimum contact period was observed as 4.0 h and from the adsorption graphs plotted as a function of time; it was established that phenol adsorption on TIWAC conformed more to a pseudosecond-order kinetic model. Additionally, it was determined that the adsorption rate is controlled by intraparticle diffusion as well as film diffusion. It was established that phenol adsorption on TIWAC can be better defined by the Langmuir adsorption model and its adsorption capacity was 142.9 mg·g–1 from the linear Langmuir equation. Temperature had an adverse effect on adsorption yield, and hence, the adsorption process was exothermic in our case. Moreover, increasing electrolyte concentration in the medium has a positive effect on adsorption yield. From the data obtained, it was concluded that the removal of phenol from aqueous solution by TIWAC produced from tea industry wastes with a very low cost took place with an extremely high performance.

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In this study, a total of 10 bacterial strains were screened for their ability to reduce cyclohexyl(phenyl)methanone 1 to its corresponding alcohol. Among these strains, Lactobacillus paracasei BD101 was found to be the most successful biocatalyst to reduce the ketones to the corresponding alcohols.The reaction conditions were systematically optimized for the reducing agent L paracasei BD101, which showed high enantioselectivity and conversion for the bioreduction. The preparative scale asymmetric reduction of cyclohexyl(phenyl)methanone (1) by L paracasei BD101 gave (S)cyclohexyl(phenyl)methanol (2) with 92% yield and >99% enantiomeric excess. The preparative scale study was carried out, and a total of 5.602 g of (S)-cyclohexyl(phenyl)methanol in high enantiomerically pure form (>99% enantiomeric excess) was produced. L paracasei BD101 has been shown to be an important biocatalyst in asymmetric reduction of bulky substrates. This study demonstrates the first example of the effective synthesis of (S)-cyclohexyl(phenyl)methanol by the L paracasei BD101 as a biocatalyst in preparative scale.

Traditional kefir grains were collected from distinct parts of Turkey, and their microbial profile was determined. A wide bacterial biota was observed formed by distinct lactic acid bacteria (LAB) in which Lactococcus lactis strains appeared to be dominant. Yeast species were also identified in kefir grains. Significant levels of antifungal and antibacterial activities were monitored in kefir isolates. All tested LAB produced an exopolysaccharide (EPS) containing glucose and galactose, and some strains formed a fructan-type EPS. Importantly, low levels of antibiotic resistance were observed among the kefir isolates. (2016) Isolation of exopolysaccharide-producing bacteria and yeasts from Tibetan kefir and characterisation of the exopolysaccharides. International Journal of Dairy Technology 69 410-417. Demirbas ß F, _ Ispirli H, Kurnaz A A, Yilmaz M T and Dertli E (2017) Antimicrobial and functional properties of lactic acid bacteria isolated from sourdoughs. LWT-Food Science and Technology 79 361-366. Dertli E and C ß on A H (2017) Microbial diversity of traditional kefir grains and their role on kefir aroma. LWT-Food Science and Technology 85 151-157. Dertli E, Mercan E, Arıcı M, Yılmaz M T and Sa gdıc ß O (2016) Characterisation of lactic acid bacteria from Turkish sourdough and determination of their exopolysaccharide (EPS) production characteristics. LWT-Food Science and Technology 71 116-124. Dertli E, Colquhoun I J, Côt e G L, Le Gall G and Narbad A (2018) Structural analysis of the a-D-glucan produced by the sourdough isolate Lactobacillus brevis E25. Food chemistry 242 45-52. Franzetti L, Galli A, Pagani M and Noni I D (1998) Microbiological and chemical investigations on sugar kefir drink. Annali di Microbiologia ed Enzimologia. 48 67-80. Gao J, Gu F, Abdella N H, Ruan H and He G (2012) Investigation on culturable microflora in Tibetan kefir grains from different areas of China. Journal of food science 77 M425-M433. Garofalo C, Osimani A, Milanovi c V, Aquilanti L, De Filippis F, Stellato G and Ercolini D (2015) Bacteria and yeast microbiota in milk kefir grains from different Italian regions. Food Microbiology 49 123-133. Gul O, Atalar I, Mortas M and Dervisoglu M (2018) Rheological, textural, colour and sensorial properties of kefir produced with buffalo milk using kefir grains and starter culture: A comparison with cows' milk kefir. International Journal of Dairy Technology 71 73-80.

The abundantly available industrial waste product Morus alba L. pomace (MAP) is one of the cost-effective biosorbent for removal of metal ions from aqueous solutions. Hence, in the present study, we aimed to test the ability of MAP to remove Cd(II) ions through batch biosorption process. Firstly, MAP was characterized using several techniques, and then the influence of various experimental parameters such as initial pH of the aqueous solution, initial Cd(II) concentration, contact time, MAP concentration, and temperature were evaluated upon the biosorption process. It was found that the maximum uptake of Cd(II) ions occurred at initial pH 6.0 and optimum contact time was observed as 60 min. Cd(II) ions adsorption on MAP analyzed by the Langmuir and Freundlich isotherm models and the maximum monolayer biosorption capacity of MAP was found to be 21.69 mg g(-1) by using the Langmuir isotherm model. The pseudo-first-order, pseudo-second-order, Elovich, and intraparticle diffusion models were employed to describe the biosorption kinetics. In order to investigate the thermodynamic properties of the biosorption process, the changes in the Gibbs free energy (∆G), enthalpy (∆H), and entropy (∆S) were also evaluated and it has been concluded that the process was feasible, spontaneous, and endothermic in the temperature range of 5-40 °C.

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Bu çalışmada, Artvin İli'nde yetişen kuşburnu (Rosa canina L.), kızılcık (Cornus mas L.), çakal eriği (Prunus spinosa) ve Ahlat armudu (Pyrus elaeagrifolia) meyvelerinden geleneksel olarak üretilen marmelatların toplam ve suda çözünür kuru madde, titrasyon asitliği, glikoz, früktoz, sakaroz, toplam şeker ve hidroksimetilfurfural (5-HMF) miktarları, pH, renk ve su aktivitesi değerleri ile antioksidan aktivite ve fenolik bileşen kompozisyonları belirlenmiştir. Araştırmada, tüm marmelat örneklerinin toplam ve suda çözünür kurumadde içeriklerinin %55, su aktivitesi değerlerinin 0.79, toplam şeker içeriklerinin 47 g/100g'ın üzerinde olduğu; HMF içeriklerinin ise 10.95 ile 1094.11 mg/kg arasında değişim gösterdiği belirlenmiştir. Örnekler farklı oranlarda gallik asit, kateşin, epikateşin, vanillin, klorojenik asit, kafeik asit, kumarik asit, p-kumarik asit, hesperidin, rutin, elajik asit ve kuersetin içermektedir. Marmelat örneklerinin fenolik madde içeriklerinin 64.67-205.75 µg GAE/g arasında değiştiği; kızılcık marmelatının en yüksek DPPH radikal giderme aktivitesi (%3.72±0.09) gösterdiği tespit edilmiştir. Çeşitli fenolik maddeleri yüksek miktarlarda içermeleri ve antioksidan aktivitelerinin yüksek olması nedeniyle kuşburnu, çakal eriği, kızılcık ve Ahlat armudu marmelatlarının insan sağlığı açısından önemli oldukları ve çeşitli fonksiyonel ürünlerin geliştirilmesinde kullanılabilecekleri düşünülmektedir. Ayrıca, çakal eriği ve Ahlat armudu marmelatlarında belirlenen yüksek HMF miktarının ürünlerin geleneksel üretimi sırasında yüksek sıcaklıkta uzun süre kaynatma işlemine maruz kalmaları nedeniyle oluştuğu düşünülmekte olup, halkımızın bu konuda bilinçlendirilmesinin faydalı olacağı anlaşılmaktadır.

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