Influence of Inoculum Preparation and Volume on Growth of Mycotoxigenic Molds

The influence of the volume and the aw of the inoculum, adjusted or not with glycerol to the aw of the medium, on growth of mycotoxigenic species of fungi was determined for Aspergillus flavus, Aspergillus ochraceus, Penicillium citrinum, Penicillium viridicatum, Fusarium tricinctum and Microdochium nivale. Statistical analysis of the data was based on the application of multivariate techniques. It was seen that at constant volumes (10 μl), P. viridicatum, A. ochraceus and M. nivale show no significant growth differences whether or not the aw of the inoculum is adjusted; but significant differences were observed with A. flavus, P. citrinum and F. tricinctum. Moreover, significant differences in growth between adjusted and unadjusted aw levels are also present when there are different inoculum volumes for A. flavus and P. citrinum. Thus, it is appropriate to adjust the inoculum to the same aw level as that of the medium or the food to be considered. In all cases, where significant differences were present, greater colony diameters were observed when the aw was adjusted. With the same inoculum preparation, different inoculum volumes also affect fungus growth, producing greater colony diameters with increments in the volume.

Download Full-text

Effect of Other Toxigenic Mold Species on Aflatoxin Production by Aspergillus flavus in Sterile Broth Shake Culture

Journal of Food Protection ◽

10.4315/0362-028x-51.6.449 ◽

1988 ◽

Vol 51 (6) ◽

pp. 449-451 ◽

Cited By ~ 9

Author(s):

PHILIP B. MISLIVEC ◽

MARY W. TRUCKSESS ◽

LEONARD STOLOFF

Keyword(s):

Aspergillus Flavus ◽

Pure Culture ◽

Aflatoxin Production ◽

Penicillium Citrinum ◽

Aspergillus Ochraceus ◽

Growth Media ◽

Shake Culture ◽

Apparent Effect ◽

Penicillium Species ◽

Heat Stable

The effect of Aspergillus ochraceus, A. versicolor, Penicillium citrinum, P. cyclopium and P. urticae on production of aflatoxin by A. flavus when grown together with A. flavus in rotary shake culture was investigated. The two aspergilli had no apparent effect on aflatoxin production, whereas all three Penicillium species substantially lowered aflatoxin production. The toxins that these penicillia produced when growing in pure culture were not found when the penicillia were grown with A. flavus. However, these toxins had no effect on aflatoxin production added to the growth media, nor did the three molds metabolize aflatoxin. When A. flavus was grown in both filter- and autoclave-sterilized filtrates of these three species, no aflatoxins were produced, although A. flavus grew well. These results suggest that although A. ochraceus and A. versicolor have no apparent effect on aflatoxin production, P. citrinum, P. cyclopium and P. urticae produce heat-stable, nonfilterable metabolite(s) which inhibit(s) aflatoxin production by actively growing A. flavus.

Download Full-text

Mycobiota and Natural Incidence of Aflatoxins, Ochratoxin A, and Citrinin in Indian Spices Confirmed by LC-MS/MS

International Journal of Microbiology ◽

10.1155/2015/242486 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 35

Author(s):

Punam Jeswal ◽

Dhiraj Kumar

Keyword(s):

Ochratoxin A ◽

Aspergillus Flavus ◽

Black Pepper ◽

Penicillium Citrinum ◽

Aspergillus Ochraceus ◽

Quantitative Detection ◽

Natural Occurrence ◽

Qualitative Detection ◽

Mycotoxigenic Fungi ◽

Natural Incidence

Nine different Indian spices (red chilli, black pepper, turmeric, coriander, cumin, fennel, caraway, fenugreek, and dry ginger) commonly cultivated and highly used in India were analysed for natural occurrence of toxigenic mycoflora and aflatoxins (AFs), ochratoxin A (OTA), and citrinin (CTN) contamination.Aspergillus flavusandAspergillus nigerwere the most dominant species isolated from all types of spices. Red chilli samples were highly contaminated with aflatoxins (85.4%) followed by dry ginger (77.7%). 56%Aspergillus flavusfrom red chilli and 45%Aspergillus ochraceusfrom black pepper were toxigenic and produced aflatoxins and ochratoxin A, respectively. Qualitative detection and quantitative detection of mycotoxins in spices were analyzed by ELISA and further confirmed by LC-MS/MS.Penicillium citrinumproduced citrinin in red chilli, black pepper, coriander, cumin, fenugreek, and dry ginger samples. The highest amount of AFs was found in red chilli (219.6 ng/g), OTA was in black pepper (154.1 ng/g), and CTN was in dry ginger samples (85.1 ng/g). The results of this study suggest that the spices are susceptible substrate for growth of mycotoxigenic fungi and further mycotoxin production. This is the first report of natural occurrence of citrinin in black pepper and dry ginger from India.

Download Full-text

Proteolytic and Lipolytic Activities of some Toxigenic and Nontoxigenic Aspergilli and Penicillia

Journal of Food Protection ◽

10.4315/0362-028x-43.5.354 ◽

1980 ◽

Vol 43 (5) ◽

pp. 354-355 ◽

Cited By ~ 3

Author(s):

S. M. EL-GENDY ◽

E. H. MARTH

Keyword(s):

Proteolytic Activity ◽

Aspergillus Flavus ◽

Aspergillus Parasiticus ◽

Lipolytic Activity ◽

The Other ◽

Aspergillus Ochraceus ◽

Penicillium Roqueforti ◽

Two Cultures ◽

Penicillium Cyclopium ◽

Penicillium Patulum

Eighteen strains of Aspergillus flavus or Aspergillus parasiticus, one of Aspergillus ochraceus and 12 strains or species of Penicillium, many of them isolated from cheese, were evaluated for their proteolytic and lipolytic activities. Strains of A. flavus exhibited considerable proteolytic and little lipolytic activity, whereas the reverse was true for strains of A. parasiticus. Of the Penicillium cultures tested, 10 exhibited considerable lipolytic activity, but only five had marked proteolytic activity. Two cultures, Penicillium patulum M59, and Penicillium cyclopium No. 8, were markedly lipolytic and proteolytic. Of the other cultures, greatest lipolytic activity was associated with Penicillium roqueforti 849, Penicillium puberulum No. 33, A. parasiticus NRRL 3145 and NRRL 465 and A. ochraceus NRRL 3174, whereas greatest proteolytic activity of all the cultures was associated with P. patulum M59, P. cyclopium No. 25 and A. flavus WB500, 4018, 4098 and NRRL 5565.

Download Full-text

ANTIFUNGAL ACTIVITIES OF CLOVE OIL AGAINST RHIZOPUS NIGRICANS, ASPERGILLUS FLAVUS AND PENICILLIUM CITRINUM IN VITRO AND IN WOUNDED FRUIT TEST

Journal of Food Safety ◽

10.1111/j.1745-4565.2011.00347.x ◽

2011 ◽

Vol 32 (1) ◽

pp. 84-93 ◽

Cited By ~ 35

Author(s):

YAGE XING ◽

QINGLIIAN XU ◽

XIHONG LI ◽

ZHENMIN CHE ◽

JUAN YUN

Keyword(s):

Aspergillus Flavus ◽

Penicillium Citrinum ◽

Clove Oil ◽

Rhizopus Nigricans ◽

Antifungal Activities

Download Full-text

Effect of Moisture and Incubation Time on Ochratoxin A Production by an Isolate of Aspergillus ochraceus

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/53.1.89 ◽

1970 ◽

Vol 53 (1) ◽

pp. 89-91

Author(s):

A F Schindler ◽

Stanley Nesheim

Keyword(s):

Statistical Analysis ◽

Moisture Content ◽

Ochratoxin A ◽

Incubation Time ◽

Maximum Yield ◽

Water Levels ◽

Aspergillus Ochraceus ◽

Ambient Temperatures ◽

Incubation Periods ◽

Transfer Needle

Abstract Experiments were conducted to determine the culture requirements that would insure a probability of high ochratoxin production with a given isolate. Experiments at ambient temperatures (72 ± 2°F) determined the levels of the two most readily controlled variables, time and moisture content, during the growth of a high toxin-producing isolate (M298) of Aspergillus ochraceus. Tests were conducted in 2.8 L - Fernbach flasks containing 100 g shredded wheat and inoculated with spores on a transfer needle. Amounts of ochratoxin A/flask were determined by comparison against standards on TLC after chloroform extraction. Statistical analysis showed a relation between ochratoxin yield, water levels, and incubation periods. A water level of 40–70 ml/flask with an incubation period of 19-21 days at ambient temperatures should give a near to maximum yield of ochratoxin A.

Download Full-text

Effects of physical preservation methods on sclerotial germination in Aspergillus flavus and Aspergillus ochraceus in stored grain

Canadian Journal of Botany ◽

10.1139/b92-151 ◽

1992 ◽

Vol 70 (6) ◽

pp. 1206-1210 ◽

Cited By ~ 4

Author(s):

M. Menasherov ◽

N. Paster ◽

R. Nitzan

Keyword(s):

Gamma Irradiation ◽

Aspergillus Flavus ◽

Combined Treatment ◽

Aspergillus Ochraceus ◽

Combined Treatments ◽

Stored Grain ◽

Modified Atmospheres ◽

Irradiation Dosage ◽

Different Levels ◽

Sclerotial Germination

Germination of sclerotia of Aspergillus flavus and Aspergillus ochraceus was assessed following gamma irradiation during exposure to different levels of relative humidities or to various modified atmospheres. The effect of combined treatments on germination was also studied. No sclerotia of either fungi germinated following irradiation with 2.5 kGy. At 80% relative humidity, germination was almost completely inhibited during 50 days of exposure. Sclerotia of A. flavus were found to tolerate higher levels of CO2 than those of A. ochraceus, and 100% germination of the former, but not the latter, occurred at 80% CO2 (given with either 20 or 5% O2). Germination of A. flavus sclerotia was markedly reduced only at modified atmospheres of 40% CO2 and 1% O2. Working with two sublethal dosages of gamma irradiation, 1.0 and 1.5 kGy, it was demonstrated that less CO2 was needed in the atmosphere (with 20% O2) to reduce germination as the irradiation dosage increased. The advantages of the combined treatment compared with each treatment applied alone are discussed. Key words: sclerotia, germination, Aspergillus, inhibition, physical methods.

Download Full-text

A GIS methodology to support sea water quality assessment in coastal areas

Global NEST Journal ◽

10.30955/gnj.002385 ◽

2018 ◽

Vol 20 (1) ◽

pp. 122-127 ◽

Cited By ~ 3

Keyword(s):

Water Quality ◽

Statistical Analysis ◽

Spatial Analysis ◽

Sea Water ◽

Rapid Development ◽

Coastal Areas ◽

Geographical Information ◽

Multivariate Techniques ◽

Analysis Methods ◽

Wide Range

The development of methodologies for assessing water quality in coastal areas including mapping of eutrophication levels is a research area of high interest. A wide range of methodological approaches can be found in the literature, including multivariate techniques, since marine eutrophication is a multi-parametric phenomenon. In this context, statistical analysis and in particular Principal Component Analysis (PCA) have been widely applied. However, no attempt has been presented so far for mapping eutrophication levels based on information acquired from PCA results in integration with spatial analysis methods. The rapid development of Geographical Information Systems provides the appropriate framework for the development and application of methodologies integrating statistical analysis, spatial analysis methods and mapping techniques. This paper proposes such a methodological approach for assessing sea water quality in coastal areas. The methodology is clearly described and the Strait of Mytilene at the east of the Island of Lesvos in the NE Aegean Sea, Greece is used as a case study.

Download Full-text

Effect of moulding on the changes in chemical composition of tabacco leaves

Acta Mycologica ◽

10.5586/am.1980.018 ◽

2014 ◽

Vol 16 (2) ◽

pp. 247-253

Author(s):

Krystyna Florczak

Keyword(s):

Chemical Composition ◽

Aspergillus Flavus ◽

Specific Protein ◽

Carbohydrate Content ◽

Aspergillus Ochraceus ◽

Penicillium Expansum ◽

Soluble Carbohydrate ◽

Aspergillus Repens

The process of moulding caused by the fungi: Aspergillus repens (Cda.) De Bart, Aspergillus flavus Link, Aspergillus ochraceus Wilhelm, Penicillium expansum (Link) Thom, VPenicillium commune Thom and Penicillum spinulosum Tom influenced the decrease in soluble carbohydrate content with the simulataneous increase in the percentage of specific protein. It had an effect on the deterioration of technological and taste values of raw tabacco.

Download Full-text