7 resultados para NANO MATERIALS
em eResearch Archive - Queensland Department of Agriculture
Resumo:
A novel method for screening bacterial isolates for their potential to inhibit the growth of ruminal methanogenic Archaea was developed using a modification of the soft agar overlay technique, formally used for the isolation of lytic bacteriophages. This method may be used in the specific, hydrogen-rich conditions required for the growth of ruminal methanogenic Archaea.
Resumo:
To collate support and extension materials to ensure the recipients of Australian cattle have, at least, a minimum understanding of animal husbandry. As the number of destination markets increases, the need will also increase to produce similar material relevant and locally sensitive for these new markets.
Resumo:
Lemon myrtle, anise myrtle, and Tasmanian pepper leaf are commercial Australian native herbs with a high volatile or essential oil content. Packaging of the herbs in high- or low-density polyethylene (HDPE and LDPE) has proven to be ineffective in preventing a significant loss of volatile components on storage. This study investigates and compares the effectiveness of alternate high-barrier property packaging materials, namely, polyvinylidene chloride coated polyethylene terephthalate/casted polypropylene (PVDC coated PET/CPP) and polyethylene terephthalate/polyethylene terephthalate/aluminum foil/linear low-density polyethylene (PET/PET/Foil/LLDPE), in prevention of volatile compound loss from the three native herbs stored at ambient temperature for 6 months. Concentrations of major volatiles were monitored using gas chromatography?mass spectrometry (GC-MS) techniques. After 6 months of storage, the greatest loss of volatiles from lemon myrtle was observed in traditional LDPE packaging (87% loss) followed by storage in PVDC coated PET/CPP (58% loss) and PET/PET/Foil/LLDPE (loss of 23%). The volatile loss from anise myrtle and Tasmanian pepper leaf stored in PVDC coated PET/CPP and PET/PET/Foil/LLDPE packaging was <30%. This study clearly indicates the importance of selecting the correct packaging material to retain the quality of herbs with high volatile content.
Resumo:
Postharvest treatments with nano-silver (NS) significantly improve water relations and therefore prolong the vase life of several cut flowers, including rose (Rosa hybrida cv. Movie Star). The efficacy of NS in alleviating bacterial related blockage in the stem-ends of cut cv. Movie Star was further investigated. Four dominant bacteria strains Pseudomonas fluorescens, Aeromonas sp., Comamonas acidovorans and Chryseomonas luteola were isolated from the stem-ends of cut roses. High numbers of the isolated bacteria at 10 8colony forming unitsmL -1 vase solution led to a sharp reduction in vase life, flower fresh weight, and water uptake. In vitro assessments of the antibacterial activity of NS against the four bacterial strains was >80% at 5mgL -1 and nearly 100% at 50mgL -1. Bacterial blockage in the stem-ends of cut cv. Movie Star roses with and without NS pulse treatments was assessed during the vase period using scanning electron microscopy. Following a 50mgL -1 NS pulse treatment, there were few bacterial cells on the cut surface of the stems even on day 7. Moreover, no obvious bacterial blockage was observed inside the xylem vessels. In contrast, the cut surface of control stems was covered with bacteria and associated amorphous substances, and numerous bacteria were found in the xylem vessels. © 2012 Elsevier B.V.
Resumo:
The relative efficacies of three chemically different nano-silver (NS) formulations were evaluated for their potential to extend the vase life of short-lived cut Acacia holosericea foliage. The novel proprietary formulations were neutral NS, acidic NS and ionic NS. They were characterised in terms of particle size, pH value, colour and odour. The NS treatments were applied as vase (lower concentrations) or pulse (higher concentrations) solutions. Among the treatments compared, neutral NS as a 4 mg L-1 vase solution or as a 40 mg L-1 24 h pulse treatment and acidic NS as a 0.5 mg L-1 vase solution or as a 5 mg L-1 24 h pulse treatment significantly (P <= 0.05) extended the vase life of A. holosericea. Vase life extensions over the deionised water (DI) controls were associated with better maintenance of relative fresh weight and vase water uptake, suppression of bacterial growth in the vase water and stem-end, and delaying stem blockage. In contrast, ionic-NS applied as a 0.5 or 1 mg L-1 vase solution treatment or as a 5 or 10 mg L-1 pulse treatment caused severe phytotoxicity to cut A. holosericea stems. The results suggest that NS treatments, especially neutral NS and acidic NS pulse treatments, could be a potential postharvest technology for commercial application to cut A. holosericea. (C) 2011 Elsevier B.V. All rights reserved.
Resumo:
Turfgrasses range from extremely salt sensitive to highly salt tolerant. However, the selection of a salt tolerant turf is not a 'silver bullet' solution to successful turf growth on salt-affected parklands. Interactions between factors such as cultivar, construction practices, establishment, and maintenance can be complex and should not be considered in isolation of one another. Taking this holistic approach, a study investigating cultivar evaluation for salt-affected sites also included a comparison of topsoil materials as turf underlay, as well as pre-treatment of the sod. The turf species and cultivars used in the study were: Cynodon dactylon, cultivar 'Oz Tuff (I) '; Paspalum vaginatum, cultivars 'Sea Isle 1 (I) ' and 'Velvetene (I) '; Zoysia matrella cultivar 'A-1 (I) '; and Zoysia japonica, cultivar 'Empire (I) '. The two underlay materials were compost (100%) or a sandy clay topsoil each applied above a coastal sand profile to a depth of 10 cm. Rooting depth or root dry weight did not significantly differ among turf cultivars. Compost profile treatment had significantly greater root mass than the topsoil among all turf cultivars. This higher root production was reflected by improved quality of all turf at the final evaluation. Turfgrass grown on compost had a higher normalised difference vegetation index (NDVI), regardless of whether full sod or bare-rooted turfgrass was used. The use of a quality underlay was paramount to the successful growth of the turf cultivars investigated. While each cultivar had superior performance in sub-optimal conditions, the key to success was the selection of the right species and cultivar for each situation combined with proper establishment and maintenance of each turf grass.