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Human milk is universally regarded as the gold standard to fulfill nutrition needs of infants. Lactoferrin (LF) is a major multiple bioactive glycoprotein in human milk but little is presented in infant formula. LF can resist digestion in the infant gastrointestinal tract and is absorbed into the bloodstream in an intact form to perform physiological functions. Evidence suggest that LF prevents pathogen infection, promotes immune system development, intestinal development, brain development and bone health, as well as ameliorates iron deficiency anemia. However, more clinical studies of LF need to be further elucidated to determine an appropriate dosage for application in infant formula. LF is sensitive to denaturation induced by processing of infant formula such as heat treatments and spay drying. Thus, further studies should be focus on maximizing the retention of LF activity in the infant formula process. This review summarizes the structural features of LF. Then the digestion, absorption and metabolism of LF in infants are discussed, followed by the function of LF for infants. Further, we summarize LF in infant formula and effects of processing of infant formula on bioactivities of LF, as well as future perspectives of LF research. [ABSTRACT FROM AUTHOR]

Human milk is the gold standard for the nutrition of infants. Human milk oligosaccharides (HMOs) are structurally diverse sugars highly abundant in human milk but not present in infant formula. The interest in HMOs has gradually increased in recent years due to their beneficial functions on infants. Here we summarize the structures and composition of HMOs, and compare the differences of oligosaccharides in human and other mammals. The absorption and metabolism of HMOs are discussed. Then we discuss existing studies on the functional biology of HMOs. Additionally, the structure-function relationships of HMOs are presented. Finally, this review summarizes the oligosaccharides in recent infant formula as well as limitations and future perspectives of HMOs research. The structures and composition of HMOs are affected by many factors. Large amounts of HMOs are metabolized by gut microbiota, and few are absorbed into circulation to perform physiological functions. Evidences from in vitro and in vivo studies, as well as clinical trials suggest that HMOs modulate gut microbiota, reduce pathogen adhesion, modulate epithelial cell and immune responses, reduce the risk of necrotizing enterocolitis and promote brain development and cognition. The specific structure determines different functions. Currently two HMOs, 2′-fucosyllactose and Lacto- N -Neotetraose, have been demonstrated safe and well-tolerated to be added into infant formula. However, the application in HMOs has been limited due to their insufficient availability. Thus, basic and clinical studies of HMOs need to be further elucidated. • The structures and composition of human milk oligosaccharides are summarized. • The absorption and metabolism of human milk oligosaccharides are discussed. • The biological functions of human milk oligosaccharides are reviewed. • The structure-function relationships of human milk oligosaccharides are presented. • The limitations and future perspectives of HMOs research are outlined. [ABSTRACT FROM AUTHOR]

Black spot rot caused by Alternaria alternata is one of the main postharvest diseases on jujube fruit. The aim of this study was to investigate the antifungal activity of methyl p -coumarate (MpCA) against A. alternata , and to elucidate the underlying mechanism involved. MpCA treatments significantly inhibited the development of black spot rot on the jujube fruit inoculated with A. alternata . Moreover, MpCA exhibited pronounced antifungal activity against mycelial growth and spore germination of A. alternata , with half-inhibition concentration of 242.5 mg L −1 . MpCA treatments caused a great leakage of intercellular electrolytes, soluble proteins, sugars and nucleotides of A. alternata during incubation, indicating that MpCA is targeted to plasma membranes of the pathogen. Furthermore, count of cells dyed with propidium iodide by flow cytometer suggested that MpCA treatments destroyed the plasma membrane integrity of spores of A. alternata . Ultrastructural observations evidenced MpCA damaged the plasma membranes and impeded the morphogenesis and growth of A. alternata , which resulted in distortion, shriveling and lysis of spores and mycelia of the pathogen. In addition, observations by confocal laser scanning microscopy and quantitative determinations confirmed that the MpCA treatments induced the formation of intercellular endogenous reactive oxygen species in the spores of A. alternata , which would lead to oxidative stress to cellular membranes and organelles. These results indicated that MpCA exerts antifungal activity through membrane damage and oxidative stress against A. alternata , and MpCA is a promising candidate for the control of postharvest diseases of jujube fruit. [ABSTRACT FROM AUTHOR]

The fungus Alternaria alternata can cause food contamination by black spot rot and food safety issues due to the production of mycotoxins. In particular, A . alternata can infect many fresh fruits and vegetables and lead to considerable postharvest decay during storage and processing. The use of plant-derived products in postharvest disease management may be an acceptable alternative to traditional chemical fungicides. The aim of this study was to assess the antifungal activity of ethyl p -coumarate (EpCA) against Alternaria alternata in vitro and in vivo , and to determine the underlying mechanism. Results indicated that EpCA exhibited pronounced antifungal activity against in vitro mycelial growth of A . alternata , with half-inhibition concentration of 176.8 μg/mL. Spore germination of the pathogen was inhibited by EpCA in a dose-dependent manner. Moreover, in vivo test confirmed that both 100 and 800 μg/mL EpCA significantly reduced disease development of black spot rot in jujube fruit caused by A . alternata . The EpCA treatments increased plasma membrane permeability as great leakage of intercellular electrolytes, soluble proteins and sugars of A . alternata occurred during incubation. The EpCA treatments also caused increase of the influx of propidium iodide, a fluorescence dye binding nucleus DNA, into the affected spores, indicating the disrupted plasma membrane integrity. Observations of ultrastructure further evidenced the damage to plasma membrane and morphology of A . alternata caused by EpCA, which resulted in distortion, sunken and shrivelled of spores and mycelia of the pathogen. In addition, fluorometric assay by confocal laser scanning microscopy confirmed that the EpCA treatments induced endogenous reactive oxygen species (ROS) formation in the spores of A . alternata , with stronger and more stable accumulation of ROS at higher concentration of EpCA. Therefore, heavy oxidative damage to cellular membranes and organelles might happen as demonstrated by the severe occurrence of lipid peroxidation of the pathogen treated with EpCA. Taken together, these results indicated that EpCA exerts antifungal activity via membrane-targeted mechanism and it would be a promising candidate to control postharvest diseases of fruits. [ABSTRACT FROM AUTHOR]

As the main consumed meat of Chinese residents, pork has a unique flavor, but the internal volatile organic compounds that cause the flavor differences between pork muscles are not clear at present. In this study, four muscles of Duroc × (Landrace × Yorkshire) pigs (loin, ham, shoulder and belly) were used as experimental subjects. Through the analysis of volatile organic compounds in four muscles of pork, the internal volatile organic compounds of different muscles of pork were discussed. Gas chromatography-ion mobility spectrometry was employed to analyze the four muscles, and volatile organic compounds in these muscles were analyzed and identified. A total of 65 volatile organic compound peaks were obtained by gas chromatography-ion mobility spectrometry. From the qualitative database, a total of 49 volatile organic compounds were identified, including aldehydes, alcohols and ketones. With the variable importance for the projection greater than 1 and significance level less than 0.05 as the criterion, the organic compounds with significant differences were screened by partial least squares-discriminant analysis and significance difference analysis. It was determined that 2-pentylfuran, 2-butanone (M), pentanal (M), butanal (D), (E)-2-hexenal, (E)-2-heptenal (D), 1,2-propanediol and 2-methylpropanal were the differential organic compounds that distinguish the four pork muscles. [ABSTRACT FROM AUTHOR]

The lipids and volatile compounds in pork from different parts, including the loin, belly, shoulder and hind leg were analyzed by triple quadrupole tandem time-of-flight mass spectrometer (Q-TOF/MS) and gas chromatography-olfactometry-mass spectrometry (GC-O-MS), respectively. Partial least squares regression (PLSR) and Pearson correlation analysis were utilized to establish the relationship between the lipids and volatile compounds. A total of 8 main flavour substances, 38 main phospholipids, and 32 main fatty acids were identified. The results showed that the key flavour compounds were mainly derived from unsaturated fatty acids and phospholipids containing unsaturated fatty acids, including oleic acid (C18:2n6c), α-Linolenic acid (C18:3n3), arachidonic acid (C20:4n6), PE O (18:1/20:4), PE O (18:2/20:4), and PE O (18:2/18:2), etc. Understanding the relationship between flavour compounds and lipids of pork will be helpful to control the quality of pork. • Non–targeted lipidomics for the identification of phospholipids. • PLS-DA analysis of the phospholipids in the four pork parts. • GC–O–MS to analyze flavour of pork from different parts. • ROAV for the key flavour compounds of pork. • The correlation of the key flavour with both fatty acids and phospholipids. [ABSTRACT FROM AUTHOR]

[Display omitted] • −30 °C is the appropriate temperature for preserving human milk at home. • Freezing at −30 °C and lower can effectively retain microorganisms in human milk. • Freezing at −30 °C and lower reduces the loss of active proteins in human milk. • Freezing at −30 °C and lower reduces lipid hydrolysis degree. • −18 °C quick freezing has no significant advantage in preserving human milk. Human milk is the best source of nutrition for infants. Lower freezing temperatures and faster freezing rates allow for better preservation of human milk. However, research on the freezing conditions of human milk is limited. This study investigated the effectiveness of quick freezing and suitable freezing conditions for home preservation. Human milk was stored under different freezing conditions (−18 °C, −18 °C quick freezing, −30 °C, −40 °C, −60 °C, and − 80 °C) for 30, 60, and 90 days and then evaluated for changes in the microbial counts, bioactive protein, and lipid. The results showed that the total aerobic bacterial and Bifidobacteria counts in human milk after storage at freezing temperatures of − 30 °C and lower were closer to those of fresh human milk compared to − 18 °C. Furthermore, the lysozyme loss, lipid hydrolysis degree, and volatile organic compound production were lower. However, −18 °C quick freezing storage was not markedly different from −18 °C in maintaining human milk quality. Based on the results, for household and environmental reasons, the recommended temperature for storing human milk is suggested as −30 °C. [ABSTRACT FROM AUTHOR]

Alternaria alternata is the major threat to postharvest storage of jujube (Ziziphus jujuba Mill.) fruit. We found that natural A. alternata infection can cause very typical phenotype of 'green ring' and 'red ring' surrounding the disease spot on the jujube fruit. The phenotype was successfully modeled and constructed on jujubes by artificial inoculation with the pathogen. Furthermore, the pathogenic infection is evidenced essential to the onset of the phenotype. The 'red ring' circle is proved to be pre-fixed to block the 'green ring' area as a battlefield combating the pathogen's attack. We monitored the global transcriptomic profiling of 'green ring' and 'red ring' tissues from jujubes infected with A. alternata, in comparison with the mock-inoculated fruit and the control intact fruit. Large amount of differentially expressed genes were obtained in 'green ring', followed by 'red ring'. Transcriptional alterations associated with the core and peripheral phenylpropanoid and lignin pathways, plant hormonal metabolisms were greatly influenced in the 'green ring' and 'red ring' by the A. alternata infection. The integrated analysis of transcriptomic profiling and metabolic changes revealed the differentially but delicately coordinated activation of these biological processes in the 'green ring' and 'red ring' on jujubes in defensing the fungal infection. [ABSTRACT FROM AUTHOR]