Effect of calcium infiltration on ripening of avocados of different maturities

Mature but unripe Fuerte and Hass avocados harvested at 3 stages of maturity were vacuum-infiltrated with 4 and 8% calcium chloride (CaCl) solutions and stored at 20°C. The fruit were assessed for ripening and injury development and analysed for Ca content. Postharvest application of Ca to fruit harvested 2 weeks before prime harvest elicited a greater delay in ripening and caused less fruit injury than application at prime harvest or 2 weeks after prime harvest. Fruit maturity did not have a significant effect on the amount of Ca taken up by fruit when infiltrated with each CaClsolution. Vacuum infiltration with 8% CaClsolution greatly enhanced the uptake of Ca by both Hass and Fuerte fruit but did not delay ripening further than 4% CaCltreatment

Changes of postharvest quality in passion fruit (Passiflora edulis Sims) under modified atmosphere packaging conditions

Abstract The modified atmosphere packaging technique was explored in order to investigate the changes of passion fruit quality during low temperature storage. Three different types of packaging condition were used in this experiment. They were (i) P-UAP, a perforated low density polyethylene (LDPE), (ii) MAP-1, a LDPE with an oxygen transmission rate (OTR) of 14000-16000 cm 3 /m 2 •day•atm, and (iii) MAP-2, an ethylene absorber laminated LDPE with an OTR of 12000 cm 3 /m 2 •day•atm. Five fresh purple passion fruits (each fruit was about 100 g) were packaged in each type of packaging and then stored at 10±1ºC, 79-84% RH. During storage, the headspace gas concentrations, physico-chemical quality and sensory acceptability were monitored. Oxygen concentration of headspace gas in MAP-1 and MAP-2 markedly decreased during 12 hours after packaging while carbon dioxide greatly increased. The gases in MAP-1 and MAP-2 reached equilibrium within 14 and 7 days, respectively. The passion fruit in all packaging conditions showed decreased presence of total soluble solids, titratable acidity and vitamin C content over the storage period. However, plastics MAP-1 and MAP-2 significantly reduced fresh weight loss and delayed fruit wrinkling. Pulp off-flavor was observed in the fruit stored in MAP-1 and MAP-2 wrapping, and this resulted in a lack of marketability. The MAP-2 plastic showed the best results in maintaining fruit quality, gas composition, and extension of storage life (up to 51 days)

Evolution and conservation in human parechovirus genomes

Human parechoviruses (HPeVs) are frequent pathogens with a seroprevalance of over 90% in adults. Recent studies on these viruses have increased the number of HPeV types to eight. Here we analyse the complete genome of one clinical isolate, PicoBank/HPeV1/a, and VP1 and 3D protein sequences of PicoBank/HPeV6/a, isolated from the same individual 13 months later. PicoBank/HPeV1/a is closely related to other recent HPeV1 isolates but is distinct from the HPeV1 Harris prototype isolated 50 years ago. The availability of an increasing number of HPeV sequences has allowed a detailed analysis of these viruses. The results add weight to the observations that recombination plays a role in the generation of HPeV diversity. An important finding is the presence of unexpected conservation of codons utilized in part of the 3D-encoding region, some of which can be explained by the presence of a phylogenetically conserved predicted secondary structure domain. This suggests that in addition to the cis-acting replication element, RNA secondary structure domains in coding regions play a key role in picornavirus replication