Evaluation of growth of Neosartorya spp. on some Nigerian fruit products     

Obeta  J. A. N.  Ugwuanyi  J. O. 《Plant foods for human nutrition (Dordrecht, Netherlands)》1997,51(4):311-320

Growth of Neosartorya fischeri, N. fischeri var. spinosa and N. quadricincta on inoculated fruit juice agars (FJAs) consisting of 1% agar and juices from mango (MJA), orange (OJA) and pineapple (PJA) containing various levels of added sucrose was studied in terms of the average number of colonies produced by their ascospores, time (days) required before colonies were formed and developed to confluent mycelial mat as well as the level of reproductive spores produced. The means of the number of colonies on PJA and OJA without added sucrose were significantly (p =0.05) higher than that of MJA. Addition of sucrose at levels of 10% to PJA, 11.5% to OJA and 9% to MJA increased the numbers of colonies whereas sucrose levels of 30% or more in PJA, 31.5% or more in OJA and 29% or more in MJA decreased the number of colonies produced. At any level of added sucrose to FJAs, a significant (p =0.05) delay occurred before the colonies were formed and developed to confluent mycelial mat except in PJA containing 10% sucrose. All cultures produced abundant cleistothecia on all FJAs without added sucrose. Addition of sucrose at levels of 30% to PJA, 31.5% to OJA and 29% to MJA resulted in the production of abundant conidial heads with a corresponding decrease in the proportion of cleistothecia.  相似文献   

Shelf life study of some Nigerian fruit juices inoculated with ascospores ofNeosartorya spp.     

J. A. N. Obeta  J. O. Ugwuanyi 《Plant foods for human nutrition (Dordrecht, Netherlands)》1997,50(4):325-331

Mango, orange and pineapple juices containing various concentrations of sucrose were dispensed in 100 ml volumes into 100 ml conical flasks with stoppers. Each juice in a flask was inoculated with ascospores of one local isolate of eitherNeosartorya fischeri, N. fischeri var.spinosa orN. quadricincta to a final concentration of 120–140 ascospores/ml of juice, and then pasteurized at 80°C for 30 min. A set of 36 inoculated flasks with 12 controls was stored at 4–5°C and two sets, one protected with 100 mg/l sodium benzoate, were stored at room temperature (25–28°C). A shelf life study was carried out on all the juices for 64 days. Only fruit juices stored at 4–5°C and those containing sodium benzoate stored at room temperature were protected from spoilage by these fungi for 64 days. Addition of sucrose at levels of 9% to mango juice, 30% to pineapple juice and 31.5% to orange juice significantly (p=0.05) protected ascospores from inactivation during cold storage.  相似文献