Bioproduction of ochratoxin A and penicillic acid by members of the Aspergillus ochraceus group

1972 ◽  
Vol 18 (5) ◽  
pp. 631-636 ◽  
Author(s):  
Alex Ciegler

Various strains of species belonging to the Aspergillus ochraceus group (A. ochraceus, A. sclerotiorum, A. alliaceus, A. ostianus, A. melleus, and A. sulphureus) can produce two mycotoxins, ochratoxin A and penicillic acid, on liquid media and in cereal grains. The quantity of each toxin produced is influenced by temperature; low temperature (10 and 20C) favor penicillic acid synthesis and higher (28C), ochratoxin A production. Generally penicillic acid is produced in yields about one to three magnitudes greater than ochratoxin A. A simple fluorodensitometric method for concomitant quantitative analysis of the two toxins has been developed based on conversion of penicillic acid and ochratoxin A to fluorescent derivatives by treatment with ammonia fumes.

2004 ◽  
Vol 50 (11) ◽  
pp. 985-988 ◽  
Author(s):  
Maria Helena Pelegrinelli Fungaro ◽  
Marciane Magnani ◽  
Laurival Antônio Vilas-Boas ◽  
Patrícia Cristina Vissotto ◽  
Márcia Cristina Furlaneto ◽  
...  

Ochratoxin A (OA) is a mycotoxin that has been found in coffee beans and coffee beverages. Its toxicological profile includes carcinogenicity, nephrotoxicity, and immunotoxicity. Aspergillus ochraceus is the major species responsible for OA production in Brazilian coffee beans. The genetic relationships among 25 A. ochraceus strains collected from Brazilian coffee-bean samples were determined based on RAPD and internal transcribed spacer (ITS) sequence data. The isolates were resolved into 2 distinct groups, one with 4 strains (group A) and the other with 21 strains (group B). Specific nucleotide variations characterizing group A and B were found for both ITS1 and ITS2 regions. Group B is a new group proposed here to accommodate the majority of the Brazilian isolates. Each group was found to contain both toxigenic and nontoxigenic strains, indicating that there is no association between molecular genotypes and the ability to produce OA.Key words: Aspergillus ochraceus, ochratoxin A, ITS region (ITS1–5.8S–ITS2), RAPD.


2021 ◽  
Vol 9 (6) ◽  
pp. 1321
Author(s):  
Ahmed Abdel-Hadi ◽  
Bader Alshehri ◽  
Mohammed Waly ◽  
Mohammed Aboamer ◽  
Saeed Banawas ◽  
...  

This study aimed to generate predictive models for growth, sporulation, and ochratoxin A (OTA) production under abiotic climatic variables, including temperatures (15–35 °C) and water activity levels (0.99–0.90 aw) by Aspergillus ochraceus group. The data were divided into three sets: one for training, one for testing, and the third one for model validation. Optimum growth occurred at 0.95 aw and 25 °C and 0.95 aw and 30 °C for A. westerdijkiae and A. steynii, respectively. Significantly improved A. westerdijkiae and A. steynii spore production occurred at 0.95 aw and 20 °C and 0.90 aw and 35 °C, respectively. A. steynii and A. westerdijkiae produced the majority of OTA at 35 °C and 0.95 aw and 25–30 °C at 0.95–0.99 aw, respectively. The accuracy of the third-order polynomial regression model reached 96% in growth cases, 94.7% in sporulation cases, and 90.9% in OTA production cases; the regression coefficients (R2) ranged from 0.8819 to 0.9978 for the Aspergillus ochraceus group. A reliable agreement was reached between the predicted and observed growth, sporulation, and OTA production. The effects of abiotic climatic variables on growth, sporulation, and OTA production of A. ochraceus group have been effectively defined, and the models generated were responsible for adequately predicted and validated models against data from other strains within A. ochraceus group that had been published in the literature under the current treatments. These models could be successfully implemented to predict fungal growth and OTA contamination on food matrices for these strains under these conditions.


Author(s):  
Aleksandra Bocarov-Stancic ◽  
Aleksandra Miljkovic ◽  
Radmila Resanovic ◽  
Ksenija Nesic ◽  
Vesna Jacevic ◽  
...  

This paper deals with the biosynthetic capacity for ochratoxin A (OTA) production by Aspergillus ochraceus E'G isolate derived from A. ochraceus CBS 108.08 strain, during 2007. Preliminary analysis of fungal potential for the production of OTA were performed according to the modified method of Filtenborg et al. (1983). Toxin production was tested in the following liquid media: (i) glucose-peptone-yeast extract broth (GPY - pH 5.6), (ii) potato-dextrose broth (PDB - pH 6.9), (iii) yeast extract-sucrose broth (YES - pH 6.5), and (iv) YES broth supplemented with 0.23 mg/l ZnSO4 x 5 H2O (YESZn - pH 6.5) after stationary and submerged cultivation. Dynamics of OTA biosynthesis was tested after the cultivation of A. ochraceus E'G on natural solid substrates, such as wet sterilized rice, corn and wheat grain. Cultivations were performed during different time periods (ranging from four days to few weeks) at different temperatures (ranging from 21?C to 30?C). The presence of OTA was determined as follows: (i) in liquid media according to the method of Balzer et al. (1978) modified by Bocarov-Stancic et al. (2003), and (ii) in the solid substrates according to the Serbian official methods for sampling and analyzing of fodder (Official Gazette of SFRY, No. 15/87). After the cultivation of A. ochraceus E'G isolate in liquid media, the highest yield of OTA (6.4 mg/l) was obtained after submerged cultivation in PDB (4 days, 128 rpm, 21-23?C). In the case of cultivation on solid substrates, the highest amount of OTA (800.0 mg/kg of dry matter) was recorded after several week long cultivation on wheat grain at 30?1?C.


2021 ◽  
pp. 155335062110148
Author(s):  
Umberto Bracale ◽  
Vania Silvestri ◽  
Emanuele Pontecorvi ◽  
Immacolata Russo ◽  
Maria Triassi ◽  
...  

Background. The COVID-19 pandemic leads to several debates regarding the possible risk for healthcare professionals during surgery. SAGES and EAES raised the issue of the transmission of infection through the surgical smoke during laparoscopy. They recommended the use of smoke evacuation devices (SEDs) with CO2 filtering systems. The aim of the present study is to compare the efficacy of different SEDs evaluating the CO2 environmental dispersion in the operating theater. Methods. We prospectively evaluated the data of 4 group of patients on which we used different SEDs or standard trocars: AIRSEAL system (S1 group), a homemade device (S2 group), an AIRSEAL system + homemade device (S3 group), and with standard trocars and without SED (S4 group). Quantitative analysis of CO2 environmental dispersion was carried out associated to the following data in order to evaluate the pneumoperitoneum variations: a preset insufflation pressure, real intraoperative pneumoperitoneum pressure, operative time, total volume of insufflated CO2, and flow rate index. Results. 16 patients were prospectively enrolled. The [CO2] mean value was 711 ppm, 641 ppm, 593 ppm, and 761 ppm in S1, S2, S3, and S4 groups, respectively. The comparison between data of all groups showed statistically significant differences in the measured ambient CO2 concentration. Conclusion. All tested SEDs seem to be useful to reduce the CO2 environmental dispersion respect to the use of standard trocars. The association of AIRSEAL system and a homemade device seems to be the best solution combining an adequate smoke evacuation and a stable pneumoperitoneum during laparoscopic surgery.


Impact ◽  
2021 ◽  
Vol 2021 (8) ◽  
pp. 64-66
Author(s):  
Shuichi Sasaki

Orthoses are devices that are applied externally to help in the rehabilitation of specific bones or joints. Dr Shuichi Sasaki, Department of Rehabilitation, Kitasato University Hospital, Japan, and his team is working to develop a new orthosis for repatriating thumb arthropathies called the Kitasato thumb splint. It is designed to improve usability of the thumb joint, especially in cases of thumb carpometacarpal (CMC) arthropathy, by taking into consideration the thumb CMC joint structure. It exerts force at the base of the CMC joint to move the thumb into the correct joint alignment, improving symptoms for patients. With the Kitasato thumb splint, Sasaki and the team are also eager to provide patients with an alternative to surgery as they believe that the use of more conservative measures with orthoses can prove effective and also prevent costly surgery. The Kitasato thumb splint is made of a low-temperature thermoplastic knit material and can be assembled in as little as 10 minutes, quickly and conveniently providing patients with additional support during painful daily tasks. In his work, Sasaki and the team are looking at orthoses used to treat thumb CMC osteoarthritis and analysing the pressure on CMC joints using quantitative analysis. So far, the Kitasato thumb splint has been found to help in pain reduction and improvements in the activities of daily living in patients with mild cases (Eaton Classifications I to II) of thumb CMC joints and to also provide some improvement in severe cases (Eaton Classifications III-IV).


2003 ◽  
Vol 17 (04n06) ◽  
pp. 842-847
Author(s):  
C. CASTELLANO ◽  
F. CORDERO ◽  
R. CANTELLI ◽  
M. FERRETTI

We report anelastic spectroscopy measurements of La 1-x Ca x MnO 3 performed in order to better characterize the nature of the phase transitions and microscopic lattice relaxation processes present in these materials. A peak in the imaginary part of the elastic susceptibility presents a behaviour typical of inhomogeneous and glass-like systems. We have performed a quantitative analysis calculating the temperature dependent distribution function of the energy barriers of the fluctuations characterizing this nanostructured state.


1970 ◽  
Vol 20 (3) ◽  
pp. 452-454 ◽  
Author(s):  
Mikio Yamazaki ◽  
Yukio Maebayashi ◽  
Komei Miyaki

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