This work investigated the impact of low-pressure cold plasma (CP) as a pretreatment with polyethylene terephthalate (PET) plastic trays or open corrugated cardboard (OCC) boxes on the overall quality of "Fan Retief" guava fruits stored for 28 days at 13°C. Untreated samples placed in PET and OCC served as control. Guava fruits followed typical climacteric responses, but CP-treated samples significantly slowed down respiration (RRCO) and ethylene production rate during storage (p ≤ 0.
View Article and Find Full Text PDFThe genus is entirely endemic to Africa, and like most cycad species, the genus is at risk of extinction. One of the threats jeopardising the future of the genus is reproduction failure, a failure that is still poorly understood. Our objective was to investigate what predisposes species to seed damages through predation, a potential cause of reproduction failure.
View Article and Find Full Text PDFMarula fruit is one of the most underutilized fruits in South Africa, and it has been reported to contain a high amount of vitamin C which is regarded as the cheapest antioxidant. The fruit pulp is traditionally extracted and boiled into juice, a process that adversely affects the vitamin C and bioactive phenolic profile of the resulting juice. This study evaluated the effects of boiling and steaming on the physicochemical properties of marula fruit juice.
View Article and Find Full Text PDFspp. establish symbioses with nitrogen (N)-fixing bacteria that contribute to soil nutrition and improve plant growth. Despite the mutualistic symbioses with N-fixing bacteria, the identity of other bacteria and their contribution to soil fertility and ecosystem functioning is not well understood.
View Article and Find Full Text PDFThis study examines the effects of nanoparticle inclusion in instantaneous saccharification and fermentation (NIISF) of waste potato peels. The effect of nanoparticle inclusion on the fermentation process was investigated at different stages which were: pre-treatment, liquefaction, saccharification and fermentation. Inclusion of NiO NPs at the pre-treatment stage gave a 1.
View Article and Find Full Text PDFThis study optimized an activated charcoal (AC) detoxification method for the reduction of three different fermentation inhibitor compounds, while minimising the reducing sugar loss from acid-pretreated sorghum leaf (SL) wastes. Process optimization demonstrated a 98%, 88% and 37% removal efficiency for furfural, 5-hydroxymethylfurfural (HMF) and acetic acid respectively, with a 7% reducing sugar loss. Subsequently, the logistic and modified Gompertz models were used to comparatively evaluate the kinetics of Saccharomyces cerevisiae growth and ethanol production using the non-detoxified (NDF) and optimized detoxified (ODF) substrate.
View Article and Find Full Text PDFHeat and odour production can have profound effects on pollination in cycads. It is therefore expected that these traits would co-vary geographically with pollinator assemblages. Such intraspecific variation, may lead to the evolution of pollination ecotypes, which can be an early stage of pollinator-mediated speciation.
View Article and Find Full Text PDFThis study reports the profiling of volatile compounds generated during microwave-assisted chemical pre-treatment of sorghum leaves. Compounds including acetic acid (0-186.26ng/g SL), furfural (0-240.
View Article and Find Full Text PDFBackground And Aims: Ontogenetic patterns of odour emissions and heating associated with plant reproductive structures may have profound effects on insect behaviour, and consequently on pollination. In some cycads, notably Macrozamia, temporal changes in emission of specific odour compounds and temperature have been interpreted as a 'push-pull' interaction in which pollinators are either attracted or repelled according to the concentration of the emitted volatiles. To establish which mechanisms occur in the large Encephalartos cycad clade, the temporal patterns of volatile emissions, heating and pollinator activity of cones of Encephalartos villosus in the Eastern Cape (EC) and KwaZulu Natal (KZN) of South Africa were investigated.
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