Effects of zinc oxide nanocomposites on microorganism growth and protection of physicochemical quality during maize storage

Maize moldy and spoilage due to microbial growth is a significant challenge in grain storage. This study aimed to evaluate the effectiveness of a zinc oxide nanocomposite, ZnO@mSiO2, prepared in our previous research, in inhibiting mold growth and preserving maize cell quality. The results demonstrated that ZnO@mSiO2 could effectively inhibit the growth of dominant microorganism, Aspergillus flavus, Talaromyces variabilis, Penicillium citrinum and Fusarium graminearum, in maize storage. Aspergillus flavus was selected as the model fungus, ZnO@mSiO2 effectively disrupted fungal hyphae structure, leading to reduced hyphal mass and inhibited spore germination. The inhibitory effect of ZnO@mSiO2 on mold growth was concentration-dependent. However, the ZnO@mSiO2 at an appropriate concentration (not exceeding 3.0 g/kg) preserved the integrity of maize cell membranes and enhancing the antioxidant activity within maize cells. The findings highlight the potential of ZnO@mSiO2 as an effective protectant to inhibit mold growth and preserve maize quality during storage.

[Selection of location for transcutaneous bilirubinometry in light therapy]

64 jaundiced neonates were measured with transcutaneous bilirubinometer for the jaundice index on the forehead and superciliary narch where was covered during photo therapy respectively. The result showed that the jaundice index in the uncovered place decreased greatly after the therapy was over, but the index went up again 12 hours later. The index on the covered place did not show this change. It is suggested that the covered place is a better site for measuring jaundice index because it can avoid the effect of phototherapy on the measuring result and make the result more accurate.

[Free radical scavenging and antifatigue activities of Saussurea involucrata polysaccharides]

The polysaccharides of Saussurea involucrata Kar et Kir was first isolated and identified by us. The polysaccharides scavenged superoxide anions by nitroblue tetraazolium colorimetric method with a median scavenging concentration of 22 micrograms.ml-1 and 95% confidence limit was 19.9-24.1 micrograms.ml-1. The polysaccharides inhibited the formation of thiobarbituric acid reaction substance in mouse liver homogenate and its IC50 was 2.3 mg/g fresh liver and 95% confidence limit was 2.05-2.55 mg/g fresh liver. By ip 25 mg.kg-1.d-1 x d in mice, the polysaccharides decreased oxygen consumption by 34.4% and ip same dosage x 6 d, the polysaccharide prolonged swimming time by 1.69-fold.