Limits...
A study on the physicochemical parameters for Penicillium expansum growth and patulin production: effect of temperature, pH, and water activity.

Tannous J, Atoui A, El Khoury A, Francis Z, Oswald IP, Puel O, Lteif R - Food Sci Nutr (2015)

Bottom Line: A mathematical model allowing the estimation of the P. expansum growth rate according to temperature, a W, and pH, was also developed.An optimal growth rate of 0.92 cm/day was predicted at 24°C with pH level of 5.1 and high a W level of 0.99.The model's predictive capability was tested successfully on artificial contaminated apples.

View Article: PubMed Central - PubMed

Affiliation: Unité de Technologie et Valorisation AlimentaireCentre d'Analyses et de RechercheUniversité Saint-JosephCampus des Sciences et TechnologiesMar Roukos, Mkallès, P.O Box 11- 514, Riad El Solh1107 2050BeirutLebanon; Research Centre in Food ToxicologyINRAUMR 1331 Toxalim180 Chemin de TournefeuilleF-31027Toulouse CedexFrance; Université de Toulouse IIIENVTINPUMR 1331ToxalimF-31076ToulouseFrance.

ABSTRACT
Penicillium expansum is among the most ubiquitous fungi disseminated worldwide, that could threaten the fruit sector by secreting patulin, a toxic secondary metabolite. Nevertheless, we lack sufficient data regarding the growth and the toxigenesis conditions of this species. This work enables a clear differentiation between the favorable conditions to the P. expansum growth and those promising for patulin production. A mathematical model allowing the estimation of the P. expansum growth rate according to temperature, a W, and pH, was also developed. An optimal growth rate of 0.92 cm/day was predicted at 24°C with pH level of 5.1 and high a W level of 0.99. The model's predictive capability was tested successfully on artificial contaminated apples. This model could be exploited by apple growers and the industrialists of fruit juices in order to predict the development of P. expansum during storage and apple processing.

No MeSH data available.


Related in: MedlinePlus

Growth curves (A), radial growth rates (cm/day) (B), and patulin production (ppm) of Penicillium expansum NRRL 35695 on Czapek glucose agar medium under different temperatures. Five different temperatures were tested (4°C, 8°C, 16°C, 25°C, and 30°C) with pH and aW values fixed to 5.2 and 0.99, respectively. The results shown are the mean of three technical replicates for each condition. The standard errors of the mean (SEM) are represented by error bars: *P < 0.05; **P < 0.01; ***P < 0.001.
© Copyright Policy - creativeCommonsBy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4930504&req=5

fsn3324-fig-0001: Growth curves (A), radial growth rates (cm/day) (B), and patulin production (ppm) of Penicillium expansum NRRL 35695 on Czapek glucose agar medium under different temperatures. Five different temperatures were tested (4°C, 8°C, 16°C, 25°C, and 30°C) with pH and aW values fixed to 5.2 and 0.99, respectively. The results shown are the mean of three technical replicates for each condition. The standard errors of the mean (SEM) are represented by error bars: *P < 0.05; **P < 0.01; ***P < 0.001.

Mentions: Colony diameters were measured on a daily basis and plotted against time. For all the tested conditions, the growth curves based on colony diameters were typical of a linear fungal growth after a short lag period ranged from 1 to 7 days (Baert et al. 2007a). However, it is worth mentioning that the fungal growth was in some cases limited by the Petri plates' dimension. In such cases, growth curves lose their linear appearance just after reaching the limiting diameter value (~7 cm) (Figs. 1A, 3A). Under each culture condition, the patulin content was quantified by HPLC and expressed in ppm.


A study on the physicochemical parameters for Penicillium expansum growth and patulin production: effect of temperature, pH, and water activity.

Tannous J, Atoui A, El Khoury A, Francis Z, Oswald IP, Puel O, Lteif R - Food Sci Nutr (2015)

Growth curves (A), radial growth rates (cm/day) (B), and patulin production (ppm) of Penicillium expansum NRRL 35695 on Czapek glucose agar medium under different temperatures. Five different temperatures were tested (4°C, 8°C, 16°C, 25°C, and 30°C) with pH and aW values fixed to 5.2 and 0.99, respectively. The results shown are the mean of three technical replicates for each condition. The standard errors of the mean (SEM) are represented by error bars: *P < 0.05; **P < 0.01; ***P < 0.001.
© Copyright Policy - creativeCommonsBy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4930504&req=5

fsn3324-fig-0001: Growth curves (A), radial growth rates (cm/day) (B), and patulin production (ppm) of Penicillium expansum NRRL 35695 on Czapek glucose agar medium under different temperatures. Five different temperatures were tested (4°C, 8°C, 16°C, 25°C, and 30°C) with pH and aW values fixed to 5.2 and 0.99, respectively. The results shown are the mean of three technical replicates for each condition. The standard errors of the mean (SEM) are represented by error bars: *P < 0.05; **P < 0.01; ***P < 0.001.
Mentions: Colony diameters were measured on a daily basis and plotted against time. For all the tested conditions, the growth curves based on colony diameters were typical of a linear fungal growth after a short lag period ranged from 1 to 7 days (Baert et al. 2007a). However, it is worth mentioning that the fungal growth was in some cases limited by the Petri plates' dimension. In such cases, growth curves lose their linear appearance just after reaching the limiting diameter value (~7 cm) (Figs. 1A, 3A). Under each culture condition, the patulin content was quantified by HPLC and expressed in ppm.

Bottom Line: A mathematical model allowing the estimation of the P. expansum growth rate according to temperature, a W, and pH, was also developed.An optimal growth rate of 0.92 cm/day was predicted at 24°C with pH level of 5.1 and high a W level of 0.99.The model's predictive capability was tested successfully on artificial contaminated apples.

View Article: PubMed Central - PubMed

Affiliation: Unité de Technologie et Valorisation AlimentaireCentre d'Analyses et de RechercheUniversité Saint-JosephCampus des Sciences et TechnologiesMar Roukos, Mkallès, P.O Box 11- 514, Riad El Solh1107 2050BeirutLebanon; Research Centre in Food ToxicologyINRAUMR 1331 Toxalim180 Chemin de TournefeuilleF-31027Toulouse CedexFrance; Université de Toulouse IIIENVTINPUMR 1331ToxalimF-31076ToulouseFrance.

ABSTRACT
Penicillium expansum is among the most ubiquitous fungi disseminated worldwide, that could threaten the fruit sector by secreting patulin, a toxic secondary metabolite. Nevertheless, we lack sufficient data regarding the growth and the toxigenesis conditions of this species. This work enables a clear differentiation between the favorable conditions to the P. expansum growth and those promising for patulin production. A mathematical model allowing the estimation of the P. expansum growth rate according to temperature, a W, and pH, was also developed. An optimal growth rate of 0.92 cm/day was predicted at 24°C with pH level of 5.1 and high a W level of 0.99. The model's predictive capability was tested successfully on artificial contaminated apples. This model could be exploited by apple growers and the industrialists of fruit juices in order to predict the development of P. expansum during storage and apple processing.

No MeSH data available.


Related in: MedlinePlus