Plant growth promoting bacteria (PGPB) are used as biostimulants to improve the growth and yield as well as the quality of crops. In the present study, nine strains of PGPB and one solid mix consisting of two of them were evaluated on the cultivation of industrial tomato under specific soil and climatic conditions. The results showed that Bacillus licheniformis treatment increased dry weight of the tomato plants by 39%, and the photosynthetic rate was increased by Priestia megaterium 9.9%. The application of Bacillus subtilis, Bacillus amyloliquefaciens, Priestia megaterium, and Bacillus licheniformis increased mean fruit weight per plant 26.78–30.70% compared to that of control. Yield per plant was increased 51.94% with the use of Bacillus licheniformis compared to that of control. The quality of the fruits in nearly every bacteria strain was improved. Bacillus pumilus and the mix of Priestia megaterium and Azotobacter chroococcum (1:1) increased the most total soluble solids in the tomato fruits (4.70° Brix), and Priestia megaterium increased content in lycopene and total carotenoids by 52.8% and 25%, respectively; Bacillus pseudomycoides increased Pectin methylesterase (PME) activity (24.94 units/mL), and Bacillusmojavensis, along with the mix of Priestia megaterium and Azotobacter chroococcum, increased Poligalacturonase (PG) activity the most (30.09 and 32.53 units/mL, respectively). Most of the bacteria strains presented an increased antioxidant activity significantly better that that of the control up to 31.25%. The results of this study confirmed that the use of PGPB as biostimulants can improve the yield and the quality of industrial tomato.
The objective of the present study was to validate a kinetic model for growth of spoilage bacteria in modified atmosphere packed (MAP) gilthead seabream fillets and to select a Time Temperature Integrator (111). The temperature and CO2 dependence of the growth of lactic acid bacteria in MAP gilthead seabream fillets was expressed by an Arrhenius-type model for the range of 0-15 degrees C and 20-80% CO2, which was validated at isothermal, variable and chill chain conditions. A new UV activatable photochemical TTI was kinetically studied and the influence of the level of activation on the response of the TTI was modelled. Applying the developed models, the required charging levels were estimated so that the 111 response was tailored to monitor the shelf life of fish fillets at selected MAP conditions, during the chill chain storage. A simulation experiment of the product distribution and storage in various chill chain conditions showed the applicability of the TTIs as shelf life monitors. (C) 2010 Elsevier Ltd. All rights reserved
1 December 2014 in Innovative Food Science & Emerging Technologies