Volume 58, Issue No. 1

https://doi.org/10.17113/ftb.58.01.20.6544

Evaluation of Process Conditions for Ultrasonic Spray Freeze Drying of Transglutaminase

Hilal Isleroglu* and Izzet Turker

Tokat Gaziosmanpasa University, Faculty of Engineering and Architecture, Food Engineering Department, Tasliciftlik Campus, 60150 Tokat, Turkey

Article history:

Received: 16 October 2019

Accepted: 11 March 2020

Key words:

spray freeze drying, ultrasonication, transglutaminase, enzyme activity, flow behaviour, particle morphology

Summary:

In this study, a commercial transglutaminase enzyme was dried using an ultrasonic spray freeze drying method and the effects of the process conditions were optimized to maximize the final transglutaminase activity. Accordingly, process parameters affecting enzyme activity were selected, such as nozzle frequency (48 and 120 kHz), flow rate (2, 5 and 8 mL/min) and plate temperature for secondary drying (25, 35 and 45 °C). Moreover, the effects of different pH values (pH=2.0 and 9.0) and high temperature (80 °C) on enzyme activity, physical properties and particle morphology of transglutaminase were discussed. According to the results, transglutaminase preserved its activity despite ultrasonic spray freeze drying. Sonication enhanced the enzyme activity. Using the desirability function method, the optimum process conditions were determined to be flow rate 3.10 mL/min, plate temperature 45 °C and nozzle frequency 120 kHz. The predicted activity ratio was1.17, and experimentally obtained ratio was 1.14±0.02. Furthermore, enzyme produced by ultrasonic spray freeze drying had low moisture values (2.92-4.36 %) at 8 h of drying. When the morphological structure of the transglutaminase particles produced by ultrasonic spray freeze drying under the optimum conditions was examined, spherical particles with pores on their surfaces were observed. In addition, flow properties of the transglutaminase powders were considered as fair under most conditions according to the Carr index.

https://doi.org/10.17113/ftb.58.01.20.6187

Supplement

Development of Efficient, Reproducible and Stable Agrobacterium-Mediated Genetic Transformation of Five Potato Cultivars

Allah Bakhsh*

Department of Agricultural Genetic Engineering, Faculty of Agricultural Sciences and Technologies, Nigde Omer Halisdemir University, 51240 Nigde, Turkey

Article history:

Received: 25 December 2018

Accepted: 6 March 2020

Key words:

potato genetic transformation, genotypes, plant growth regulators, cost-effective protocol

Summary:

The developments in transformation technology have enabled the scientists to incorporate, mutate or substitute gene(s) leading to a particular trait; advancing it to a point where only few technical limitations remain. Genotype dependency and explant types are important factors affecting transformation efficiency in potato. In the present study, a rapid, reproducible and stable Agrobacterium-mediated transformation procedure in potato was developed by a combination of different plant growth regulators. Leaf discs and internodal explants of five cultivars of potato, i.e. Lady Olympia, Granola, Agria, Désirée and Innovator were infected with Agrobacterium tumefaciens strain LBA4404 containing pBIN19 expression vector with β-glucuronidase gusA gene under the control of 35S CaMV promoter. Kanamycin was used as plant selectable marker for screening of primary transformants at concentration of 100 mg/L. Both explants responded positively; internode being more suitable explant for better transformation efficiency. Based on GUS histochemical assay, the transformation efficiency was 22, 20, 18.6, 15 and 10 % using the internodal explant, and 15, 12, 17, 8 and 6 % using leaf discs as explant in Lady Olympia, Granola, Agria, Désirée and Innovator respectively. Furthermore, PCR assays confirmed the presence of gusA and nptII genes in regenerated plants. The molecular analysis in succeeding progeny showed proper integration and expression of both genes. The results suggest Lady Olympia as the best cultivar for future transformation procedures. Overall, the short duration, rapidity and reproducibility make this protocol suitable for wider application of transgenic potato plants.

https://doi.org/10.17113/ftb.58.01.20.6531

Supplement

Identification of Durum Wheat Cultivars and Their Tetraploid Relatives with Low Cadmium Content

Mehmet Tekin¹, Ahmet Cat², Sahriye Sönmez³and Taner Akar¹*

¹Akdeniz University, Faculty of Agriculture, Department of Field Crops, 07059 Antalya, Turkey

²Akdeniz University, Faculty of Agriculture, Department of Plant Protection, 07059 Antalya, Turkey

³Akdeniz University, Faculty of Agriculture, Department of Soil Science, 07059 Antalya, Turkey

Article history:

Received: 8 October 2019

Accepted: 29 March 2020

Key words:

durum wheat characterization, low Cd content, tetraploid wheat, marker-assisted breeding

Summary:

In this study, 71 durum wheat cultivars (Triticum durum Desf.), 22 emmer wheat (Triticum dicoccum L.) and 11 wild emmer (Triticum dicoccoides L.) genotypes were genetically characterized to determine the alleles associated with high cadmium (Cd) content. After genotypic characterization, 14 cultivars selected among all genotypes with low and high Cd content were phenotyped by a pot experiment to verify the genotypic data. Identification of 32 durum wheat, one emmer wheat and four wild emmer genotypes showed that they have alleles associated with high Cd content, while 68 genotypes of which 39 durum wheat, 21 emmer wheat and 7 wild emmer cultivars had alleles associated with low Cd content. Moreover, phenotypic data obtained from pot experiment were similar to the molecular data. To sum up, the marker successfully classified durum wheat cultivars into either high or low accumulators and these results can be safely used in breeding programs to improve new durum wheat cultivars with alleles associated with low Cd content. Due to routine use of phosphorus fertilizers in agricultural areas and other anthropogenic factors related to Cd toxicity, new durum wheat cultivars with low Cd content should be urgently developed for safe production of macaroni or other types of wheat products for human and animal consumption.