The Postharvest Application of Carvone, Abscisic Acid, Gibberellin, and Variable Temperature for Regulating the Dormancy Release and Sprouting Commencement of Mini-Tuber Potato Seeds Produced under Aeroponics.

This study investigated the efficacy of carvone, abscisic acid (ABA), gibberellin (GA3), and variable temperature in managing dormancy and sprouting in aeroponically grown mini-tuber potato (Solanum tuberosum L.) seeds. The results showed that carvone treatment effectively reduced the weight loss rate by 12.25% and decay rate by 3.33% at day 25 compared to control. ABA treatment significantly enhanced the germination rate, increasing it to 97.33%. GA3 treatment resulted in the longest sprouts of 14.24 mm and reduced the MDA content by 23.08% at day 30, indicating its potential in shortening dormancy and maintaining membrane integrity. The variable-temperature treatment demonstrated a balanced performance in reducing weight loss and maintaining a lower relative conductivity, indicating less cellular damage. The enzymatic activities of α-amylase, CAT, and SOD were modulated by the treatments, ensuring a balanced enzymatic environment for seed vitality. These results establish a solid basis for improving postharvest management strategies to optimize germination uniformity and preserve the quality of aeroponic potato seeds during extended dormancy, promising enhanced yield and productivity in potato cultivation.

Effects of the mashing process and macromolecule contents on the filterability of barley malt.

The filterability of barley malt is a critical quality parameter in beer brewing. The effects of two mashing processes (processes A and B) on the filterability of the three barley malts and their macromolecule contents were investigated. Filtration volume increased by 4%, 9%, and 13% for the Baudin, Ganpi, and Gangpi malts, respectively, and the final filtration volume of Gangpi was still poorer than that of Baudin. A downward mashing process (process C) was applied to measure the ß-glucan, arabinoxylans (AX), the polymeric arabinoxylan (PAX), and high molecular weight nitrogen (HMWN) content. The ß-glucan degradation rate of well-modified malt during malting was higher than that of poorly modified malt, whereas the PAX and HMWN solubilization rates during malting were lower in well-modified malt than in poorly modified malt. The filterability of poorly modified malt did not effectively improve with an initial mashing phase at 37℃. ß-Glucan degradation and PAX and HMWN solubilization during malting were critical for ensuring malt quality. Thus, the goal of predicting the filterability of malt was achieved by applying a downward mashing process. PRACTICAL APPLICATION: Quality of wort and beer as well as production efficiency is affected by the malt quality. The filterability of barley malt can affect the production efficiency and quality of wort. The change in the macromolecule contents during malting is important to ensure the production of high-quality malt. The results of this study can provide a good method for the detection of malt filtration performance, and it also may contribute to the purpose of prediction the changes in barley malt and the resulting barley malt filterability.

Combined effects of ultrasound and aqueous chlorine dioxide treatments on nitrate content during storage and postharvest storage quality of spinach (Spinacia oleracea L.).

The objectives of this study were to optimize the condition of ultrasonic treatment combined with aqueous chlorine dioxide (ClO2) on nitrate content of spinach by response surface methodology (RSM), and determine the effectiveness of ultrasound (US) and ClO2 alone and in combination, on spinach postharvest quality during 7 days' storage period. The optimal treatment parameters obtained were ultrasonic power (300 W), ClO2 concentration (50 ppm), treatment time (4 min). The combined treatments significantly reduced the nitrate content and maintained better storage quality in terms of total soluble solids (TSS) and ascorbic acid content compared with the individual treatment or untreated. For Chlorophyll content, the combined treatment was significantly higher than the control and ClO2 treatment, but lower than ultrasonic treatment. The results demonstrated that US combined with ClO2 are promising alternatives for the reduction of nitrate content, as well as preserving the quality of stored leafy vegetables.

Contribution of Disulfide Bridges to the Thermostability of a Type A Feruloyl Esterase from Aspergillus usamii.

The contribution of disulfide bridges to the thermostability of a type A feruloyl esterase (AuFaeA) from Aspergillus usamii E001 was studied by introducing an extra disulfide bridge or eliminating a native one from the enzyme. MODIP and DbD, two computational tools that can predict the possible disulfide bridges in proteins for thermostability improvement, and molecular dynamics (MD) simulations were used to design the extra disulfide bridge. One residue pair A126-N152 was chosen, and the respective amino acid residues were mutated to cysteine. The wild-type AuFaeA and its variants were expressed in Pichia pastoris GS115. The temperature optimum of the recombinant (re-) AuFaeAA126C-N152C was increased by 6°C compared to that of re-AuFaeA. The thermal inactivation half-lives of re-AuFaeAA126C-N152C at 55 and 60°C were 188 and 40 min, which were 12.5- and 10-folds longer than those of re-AuFaeA. The catalytic efficiency (kcat/Km) of re-AuFaeAA126C-N152C was similar to that of re-AuFaeA. Additionally, after elimination of each native disulfide bridge in AuFaeA, a great decrease in expression level and at least 10°C decrease in thermal stability of recombinant AuEaeA variants were also observed.