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Summary: To have a better understanding of regulatory mechanism of carotenoid accumulation in sweetcorn (Zea mays L.), we analysed carotenoid profiles, expression patterns of carotenogenic genes and antioxidant activities in two genotypes of sweetcorn during kernel development. The results suggested that the expression of carotenogenic genes played an essential role in carotenoid accumulation and higher expression levels of carotenogenic genes obviously led to higher levels of total carotenoids. It was found that the expression of upstream genes (ZmPDS,ZmZDS and ZmCRTISO) had major influence on the content of total carotenoid during kernel development. The accumulation of lycopene was closely related to the coordination of upstream and downstream genes. The expression of ZmHYD and ZmZEP was influential on zeaxanthin accumulation, which was also influenced by the rate of ZmCHYB/ZmCHYE. Expression levels of ZmCHYE were still stable in order for α‐xanthophylls largely accumulated during kernel development. Lutein, zeaxanthin, α‐cryptoxanthin and β‐cryptoxanthin constituted the predominant carotenoids in sweetcorn. Two essential stages for carotenoid accumulation were found in sweetcorn during kernel development. [ABSTRACT FROM AUTHOR]

Coastal vegetation not only mitigates the damage inflicted by marine disasters on coastal area, but also plays an important role in the global carbon cycle (i.e. blue carbon). Nevertheless, detailed records of both long-term changes in coastal vegetation composition and diversity, coupled with climate change and river evolution, remain sparse. To explore vegetation dynamics and their influencing factors on the coastal area of the Bohai Sea (BS) during the Holocene, in this study, we present high-resolution pollen and grain size data obtained from a sediment core of the BS. The results reveal that two rapid and abrupt changes in salt marsh vegetation are linked with the river-system changes. Within each event, a recurring pattern - starting with a decline in Cyperaceae, followed by an increase in Artemisia and Chenopodiaceae - suggests a successional process that is determined by the close relationship between Yellow River (YR) channel shifts and the wetland community dynamics. The phreatophyte Cyperaceae at the base of each sequence indicate lower saline conditions. Unchannelized river flow characterized the onset of the YR channel shift, caused a huge river-derived sediment accumulation in the floodplain, and destroyed the sedges in the coastal depression. Along with the formation of a new channel, lateral migration of the lower channel stopped, and a new intertidal mudflat was formed. Pioneer species (Chenopodiaceae, Artemisia) were the first to colonize the bare zones of the lower and middle marsh areas. In addition, the pollen results revealed that the vegetation in the Shandong Peninsula was dominated by broadleaved trees during the early Holocene (8500-6500aBP) and by conifers and broadleaved forests in the middle Holocene (6500-3500aBP), which was followed by an expansion of broadleaved trees (3500-1000aBP). After 1000aBP, human impacts are recognized as a sudden decrease in Quercus and a marked increase in secondary vegetation Pinus. The pollen-based temperature index indicated that a warmer early and late Holocene and colder middle Holocene were consistent with previously reported temperature records for North and Northwest China. The main driving factors of temperature variation in this region are insolation, greenhouse gases and the El Niño-Southern Oscillation. [ABSTRACT FROM AUTHOR]

• Metabolite profiling of AAA-, AAB-, ABB-genome banana during postharvest ripening. • Accumulation of carotenoids and amino acids show genotype-dependent patterns. • High carotene levels are correlated with low levels of glycolysis-derived AAs. • High carotene levels are correlated with high levels of TCA cycle-derived AAs. Banana fruits have attracted considerable attention for health-promoting effects attributed to ubiquitous functional metabolites. However, genotype-dependent accumulation patterns of carotenoids in banana remain largely unclear. Here, we performed a systematic metabolomic investigation of 18 banana cultivars of the AAA, AAB, or ABB genome groups. Our results indicate that the levels of soluble sugars increase during postharvest ripening regardless of genotype, whereas amino acids (AAs) and tricarboxylic acid (TCA) cycle-derived organic acids display genotype-dependent patterns. The levels of AAs derived from the glycolytic pathway increased, whereas those derived from the TCA cycle significantly decreased during ripening. The carotenoid composition in banana pulp was genotype-specific, and the contents of α-carotene were the highest in AAA-genome bananas. Moreover, high α-carotene and β-carotene contents in banana were correlated with elevated levels of TCA cycle-derived AAs and decreased levels of glycolysis-derived AAs. Taken together, these findings provide a comprehensive understanding of genotype-associated carotenoid accumulation, thereby facilitating the breeding of future high carotenoid banana cultivars. [ABSTRACT FROM AUTHOR]

Ghee, a traditional fermented dairy product and dietary staple for inhabitants of the Tibet Plateau, has unclear lipid profiles and flavor formation mechanisms. This study aims to characterize superior ghee varieties and elucidate factors driving the production of beneficial lipids and flavor compounds. Through a comprehensive analysis of lipidomic profiles, volatile organic compound (VOC) release and microbial dynamics during ghee production from Holstein milk (HM) and Jersey milk (JM), A total of 126 differential lipids were identified, primarily associated with glycerophospholipid and sphingolipid metabolism. Additionally, 69 VOCs were detected, with 23 recognized as critical to flavor development. Key microbial species, including Lactococcus, Lactobacillus, Acetobacter, and Lacticaseibacillus, enriched during fermentation, were found to drive both VOC release and free fatty acid (FFA) production, particularly of eicosapentaenoic acid (EPA) and long-chain fatty acids. Notably, ghee derived from JM exhibited higher levels of functional lipids, beneficial FFAs, and critical VOCs compared to Holstein ghee (HG). The fermentation process, supported by microbial activity and enzyme production, significantly enriched these compounds, underscoring the pivotal role of microbes in enhancing both health benefits and flavor. These findings have potential implications for improving the quality of fermented dairy products in the food industry., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Aflatoxins (AFs) are highly carcinogenic metabolites produced by Aspergillus species that can contaminate critical food staples, leading to significant health and economic risks. The cytochrome P450 monooxygenase AflG catalyzes an early step in AF biosynthesis, resulting in the conversion of averantin (AVN) to 5'-hydroxy-averantin. However, the molecular mechanism underlying the AflG-AVN interaction remains unclear. Here, we sought to understand the structural features of AflG in complex with AVN to enable the identification of inhibitors targeting the AflG binding pocket. To achieve this goal, we employed a comprehensive approach combining computational and experimental methods. Structural modeling and microsecond-scale molecular dynamics (MD) simulations yielded new insights into AflG architecture and unveiled unique ligand binding conformations of the AflG-AVN complex. High-throughput virtual screening of more than 1.3 million compounds pinpointed specific subsets with favorable predicted docking scores. The resulting compounds were ranked based on binding free energy calculations and evaluated with MD simulations and in vitro experiments with Aspergillus flavus . Our results revealed two compounds significantly inhibited AF biosynthesis. Comprehensive structural analysis elucidated the binding sites of competitive inhibitors and demonstrated their regulation of AflG dynamics. This structure-guided pipeline successfully enabled the identification of novel AflG inhibitors and provided novel molecular insights that will guide future efforts to develop effective therapeutics that prevent AF contamination., Competing Interests: MY and DW were employed by DP Technology. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wang, Zhou, Yang, Niu, Huang, Chen, Chen, Wang, Zhang, Wu and Yan.)

Walnut (Juglans regia L.) is an abundant source of polyphenols. Although phenolic species in the walnut kernel have been studied comprehensively, their compositional profile in the internal fruit septum, a traditional nutraceutical material in China, has been rarely explored. In the current study, the methanolic extract of the walnut septum was analysed by Ultra-performance liquid chromatography coupled with Orbitrap mass spectrometry. Totally seventy-five phenolics belonging to flavonoids, tannins and phenolic acids were identified based on mass spectra, references and literatures. Among them, quercetin-3-O-galactoside, quercetin-rhamnose-pentoside, quercetin-3-O-glucoside, quercetin-rhamnose-hexoside, kaempferol-rhamnoside, and two isomers of quercetin-rhamnoside were reported for the first time in walnut. The total polyphenol content was found to be 122.78 ± 2.55 mg GAE/g dry weight in septum. This study is the first to comprehensively investigate and identify phenolic compounds in the fruit septum of walnut and indicates that the septum to be a rich resource of polyphenols., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Seeds with high oil contents are more susceptible to aflatoxin contamination after infected by Aspergillus species. However, in vitro studies showed that different types of fatty acids have striking difference on fungal growth, sporulation and aflatoxin biosynthesis in Aspergillus. Recent studies revealed that, although all fatty acids examined promote aflatoxin production, oxidized polyunsaturated fatty acids inhibit aflatoxin biosynthesis. The inhibiting effect is derived from oxylipins produced during autoxidation. In this article, we provide an overview for recent progress in fatty acids and oxylipins on fungal growth, sporulation and aflatoxin production in Aspergillus species.