Study on the effect of fengycin on the respiration and metabolic mechanism of Penicillium expansum

This study investigate the inhibiting effect of fengycin on respiration and nutrient utilization of Penicillium expansum. The respiratory inhibition rate of the P. expansum was determined by the test of dissolved oxygen fengycin, The effect of fengycin treatment on the activity of P. expansum mitochondrial complex enzyme was detected by mitochondrial enzyme activity assay. The ability of fengycin treatment to P. expansum the utilization of total sugar and total protein was determined by DNS colorimetric method and biuret method. After fengycin treatments, the TCA pathway of respiratory metabolism in P. expansum was inhibited. Besides, fengycin could block the gene expression in P. expansum by binding P. expansum mitochondrial complex enzyme II and III related genes. Therefore, the activity of mitochondrial enzymes was affected. With the increasement of fengycin concentration, the absorption and utilization capacity of P. expansum to total sugar and total protein decreased significantly. Fengycin could inhibit the respiratory metabolism and reduce the biochemical metabolism level in P. expansum and finally caused the growth inhibition.

Hypoventilation Yoga Exercises: Effects on Respiratory Metabolism

Aim. Assessment of changes in respiratory metabolism and parameters of external respiration during hypoventilation yoga exercises. Material and methods. 22 experienced volunteers (18 men and 4 women, mean age 42.95 ± 8.14 years) performed yoga breathing exercises with a frequency of 3 times per minute, 1.5 times per minute, 1 time per minute, as well as free breathing for 2 minutes. Respiratory rate (RR), minute ventilation (MV), tidal volume (TV), partial pressure of CO2 in expired air at the end of exhalation (PetCO2), percentage of O2 in expired air (FeO2) and hemoglobin saturation (SpO2) were recorded. Results and discussion. The breathing regimen with RR = 3 times / min is hyperventilating, accompanied by a statistically significant increase in respiratory minute volume (RMV) and a decrease in PetCO2; hemoglobin saturation indices are not changed. Breathing with a frequency of 1.5 times/min is accompanied by a statistically significant decrease in RMV compared to the rest state, as well as an increase in PetCO2 and a decrease in FeO2, that is, it is hypoventilating, although there is a certain heterogeneity within this subgroup depending on the recruited tidal volume. Indicators of hemoglobin saturation with a given breathing mode do not change. The breathing regimen with RR = 1 time / min is accompanied by a statistically significant decrease in the RMV, an increase in PetCO2 and a decrease in FeO2; the average values of hemoglobin saturation do not change, but the minimum saturation values (observed once during each respiratory cycle) are statistically significantly lower than at the rest state. These results suggest that hypoventilating yoga exercises may have a positive effect on cerebral blood flow and cerebrovascular reactivity. Conclusion. Performing yoga breathing exercises at the respiration rate of 1.5 and 1 times per minute is accompanied by statistically significant hypoventilation, alveolar hypercapnia and hypoxia.

Hydro-Electro Hybrid Priming Promotes Carrot (Daucus carota L.) Seed Germination by Activating Lipid Utilization and Respiratory Metabolism

Carrot (Daucus carota L.) is widely cultivated as one of the most important root crops, and developing an effective presowing treatment method can promote the development of modern mechanized precision sowing. In the present study, a novel seed priming technology, named hydro-electro hybrid priming (HEHP), was used to promote the germination of carrot seeds. Seed germination experiments showed that HEHP was able to increase the germination index (GI) and vigor index (VI) by 3.1-fold and 6.8-fold, respectively, and the effect was significantly superior to that of hydro-priming (HYD) and electrostatic field treatment (EF). The consumption and utilization rate of seed storage reserves were also greatly improved. Meanwhile, both glyoxysomes and mitochondria were found to appear ahead of time in the endosperm cells of HEHP through observations of the subcellular structure of the endosperm. Activities of isocitrate lyase (ICL), NAD-dependent malate dehydrogenase (MDH), pyruvate kinase (PK), and alcohol dehydrogenase (ADH) were significantly increased by HEHP. From transcriptome results, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to the glyoxylate cycle, glycolysis, gluconeogenesis, and the citrate cycle were significantly enriched and real-time quantitative PCR (qRT-PCR) analysis confirmed the expression pattern of 15 critical differentially expressed genes (DEGs) in these pathways. All DEGs encoding MDH, phosphoenolpyruvate carboxykinase (PEPCK), and PK were upregulated in HEHP; thus, it is reasonable to infer that the transformation of malate, oxalacetate, phosphoenolpyruvate, and pyruvate in the cytoplasm may be pivotal for the energy supply during early germination. The results suggest that the optimal effect of HEHP is achieved by initiating stored lipid utilization and respiratory metabolism pathways related to germination.