Search

Key message: Hydrogen sulfide improved cold resistance of tomato fruits by regulating energy metabolism and delaying cell wall degradation, thereby alleviating the damage of cold storage on fruits. Postharvest cold storage in tomato fruits extended shelf life but caused the appearance of chilling injury (CI), appeared by softness and spots on the surface of the fruits. These changes were linked closely with energy and cell wall metabolisms. Hydrogen sulfide (H2S), as the gaseous fresh-keeping regulator, was used in the present study to investigate the effects of H2S on energy and cell wall metabolisms in tomato fruits during cold storage. Fruits after harvest were fumigated with different concentrations (0, 0.5, 1, 1.5 mM) of sodium hydrosulfide (NaHS) solution as H2S honor for 24 h and stored at 4 °C for 25 days. The results showed that 1 and 1.5 mM NaHS solution fumigation promoted the accumulation of endogenous H2S, followed by the increase in L-cysteine desulfurase (LCD) and D-cysteine desulfurase (DCD) activities in fruits during cold storage. It was also found that 1 and 1.5 mM NaHS treatments improved H+-ATPase, Ca2+-ATPase, cytochrome C oxidase (CCO), and succinic dehydrogenase (SDH) activities. Moreover, the contents of cellulose and hemicellulose were increased by 1 and 1.5 mM NaHS, following down-regulated activities of cellulase (CL), pectin lyase (PL), α-mannosidase (α-man) and β-Galactosidase (β-Gal) and down-regulated expression of PL1, PL8, MAN4 and MAN7 genes. Thus, H2S alleviates CI led by cold storage in tomato fruits via regulating energy and cell wall metabolisms. [ABSTRACT FROM AUTHOR]

Functional gastrointestinal disorders (FGIDs) are common among the aircrew due to their arduous working environment. This study investigated the prevalence of FGIDs in Chinese male pilots and assessed the effects of trigger factors on the FGIDs. A cross-sectional study including 212 male pilots was performed in a Chinese large civil airline company. FGIDs were diagnosed according to the Rome IV diagnostic criteria. The psychological performance, dietary pattern, sleep situation, and physical activity of the respondents were assessed. Logistic regression analysis and structural equation modeling were used to explore the association between these trigger factors and FGIDs. FGIDs were observed in 83 (39.22%) respondents, of which 31 (37.35%) had overlap syndromes. Age, flight level, flight time, high-salt food pattern, anxiety, and sleep performance were found to be associated with FGIDs (all P < 0.05). Stepwise logistic regression analysis revealed that the flight level (OR 0.59, 95% CI 0.31–0.080), high-salt food pattern (OR 2.31, 95% CI 1.28–4.16), and sleep performance (OR 2.39, 95% CI 1.11–5.14) were the influencing factors associated with FGIDs. Structural equation modeling confirmed the correlations between FGIDs and the occupational, dietary, and psychological factors with a reasonable fit. The preventive strategies were necessitated according to occupational and psychological characteristics. [ABSTRACT FROM AUTHOR]