Lactic acid bacteria (LAB) play a crucial role in the malolactic fermentation (MLF) of wine, contributing to flavor improvement, acidity reduction, and microbial stability. However, the high alcohol concentration in wine poses a significant challenge of lactic acid bacteria. Ethanol can disrupt cell membrane integrity, inhibit metabolism, and induce oxidative stress, ultimately impairing cell growth and fermentation performance. This article provides a comprehensive review of the multi-layered defense mechanisms of lactic acid bacteria in response to ethanol stress during wine fermentation, by summarizing the key genes and proteins involved in cell membrane, intracellular metabolism, antioxidant systems, and biofilm formation. Understanding the molecular mechanisms of ethanol tolerance can help screen and cultivate strains with high ethanol tolerance, thereby improving the survival rate of lactic acid bacteria and enhancing the efficiency and reliability of the fermentation process.

Malolactic fermentation, started by lactic acid bacteria, plays a crucial role in the production of high-quality wines. As global warming increases the ethanol content in wines, the success of malolactic fermentation depends on selecting ethanol-tolerant strains, especially for wines from increasingly warm climates. Lentilactobacillus hilgardii Q19 was isolated and characterized as an indigenous malolactic bacterium with higher ethanol tolerance properties. In this study, it was indicated that ethanol stress had significant effects on ATPase activity, antioxidant system, and cell membrane of L. hilgardii Q19 by measuring the physiological indicators under stress which include H+-ATPase, Na+/K+-ATPase, Ca2+/Mg2+-ATPase activity, glutathione content, superoxide dismutase (SOD) activity and intracellular reactive oxygen species (ROS) content. The main metabolic pathways involved in ethanol stress such as ATP-binding cassette (ABC) transporters, pentose phosphate pathway, phosphotransferase system, glutathione metabolic pathway and two-component systems were screened by transcriptome sequencing analysis. The functions of the pentose phosphate pathway, pyruvate metabolic pathway and glycerolipid metabolism under ethanol stress were verified by constructing the L. hilgardii Q19 ethanol stress related key genes gntK, pyk, and glpK overexpression vectors. The above findings may contribute to our understanding of the metabolic pathways and regulatory mechanisms of L. hilgardii Q19 in response to ethanol stress.

This investigation aimed to propose and develop a colorimetric and ratiometric fluorescent probe that enables rapid detection of sulfites in preserved fruit while excluding potential interference. A convenient synthesis of the semi-cyanines was conducted from benzothiazole and the photophysical behaviors of subsequent compounds were recorded. After optimization, a practical method for determining residual sulfite was established based on the variations in Em480 nm/Em640 nm (ex. at 410 nm) (R-2 > 0.99). The sulfur content of the samples determined using this probe was found to be consistent with the results obtained from the standard method (P > 0.05), with peak recovery ranging from 96.34 % to 115.5 %. These results demonstrate that this probe can be complement standard methods, thereby ensuring food safety.

As one of the traditional pretreatments for many Chinese herbal medicines, Sulfur Fumigation might remain residual sulfites which would endanger human health when overdosage. It should be invaluable to monitor their residual content in food or medicines. Abundant novel fluorescent probes for sulfur dioxide were designed, constructed and evaluated with excellent sensitivity, but lack in specificity. One of numerous potential candidates based on semi-cyanine fluorophores, N-3-I was synthesized, characterized and identified as the satisfactory candidates for the rapid detection of sulfites (<1 min) in aqueous solution, high sensitivity (limit of detection at 4.54 nM, Na2SO3), excellent specificity (only towards sulfites) and satisfactory fluorescence variation (>500-fold, λmax = 488 nm, ex. 414 nm). Furthermore, the assay based on N-3-I was established and could quantitatively assess the accurate content of sulfites in the actual sample after optimization with the advantages of short time, less sample material required, low cost and high accuracy, which was comparable with standard method in the rapid detection of wine and solid samples, such as Chinese traditional herbs. The probe demonstrates a high potential for the accurate and rapid detection of sulfur dioxide in the real samples to assure the food safety.

In this study, Antarctic krill oil was extracted using supercritical carbon dioxide (CO2) and ethanol solvent, both with and without refinement, to assess its quality, composition, and anti-inflammatory benefits. The supercritical extracted krill oil (SKO) exhibited superior qualities, with a high yield of astaxanthin (589.00 +/- 9.85 mu g/g) and a notable content of total fatty acids (FA) and monounsaturated fatty acids (MUFA) reaching 97.06% and 29.65%, respectively, surpassing that of refined krill oil (RKO). SKO exhibited a more pronounced inhibitory effect on the NF-kappa B pathway compared to RKO.

This study investigated the dynamic profiles of microorganisms and metabolites in jaboticaba wine (JW) using metabolomic and metagenomic approaches. The free amino acids of JW decreased 9.6-fold during fermentation, and a total of 69 volatile compounds were identified, of which 15 belonged to the key aroma compounds. Metabolomic analysis showed that during the early stages of fermentation, Hanseniaspora and Pichia were the most abundant non-Saccharomyces yeasts. As fermentation progressed, Saccharomyces, Schizosaccharomyces, Saitoella, and Pseudomicrostrobilus dominated and were involved in ethanol synthesis. Metabolic network analysis showed that yeasts play a key role in substrate degradation and flavor formation, while other dominant microorganisms actively contribute to these processes. This study provides insights into the modulation of JW's flavor by microorganisms.

This study investigated the structural characteristics and anti-inflammatory potential of Tremella fuciformis stem byproduct-derived polysaccharide TFP-1. Structural analysis revealed that TFP-1 is an acetylated heteropolysaccharide composed of mannose, xylose, fucose, and glucuronic acid in a molar ratio of 6.18:1.09:2.13:1. It likely has a 3-alpha-d-Manp backbone, branched by T-alpha-l-Fucp, 2-beta-d-Xylp, and T-beta-d-GlcAp at the O-2 position, with partial acetylation at C6-OH of mannoses. The anti-inflammatory activity of TFP-1 was also assessed. It was shown to inhibit the production of inflammatory factors in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages by regulating the NF-kappa B pathway. These findings suggest TFP-1 may serve as a potential anti-inflammatory supplement.

To monitor the biological function of H2S in real time, this investigation demonstrated the design and synthesis of a novel fluorescent probe integrated with cyanine and 2,4-dinitrophenol for the qualitative and quantitative detection of H2S. An NIR sensitive sensor (FS-HS-1) was provided with a straightforward process. Spectroscopy experiments elucidated that FS-HS-1 could selectively detect H2S in a PBS solution (containing 40% acetonitrile) with a 111-fold fluorescence enhancement at 715 nm (ex. 605 nm). The response towards NaHS occurred in less than 2 min, and the detection limit was confirmed to be as low as 4.47 ± 0.11 nmol/L. Furthermore, the probe is capable of monitoring changes in exogenous H2S concentrations within living cells with confocal and 2P imaging.

Mercury, one of the various harmful metals, is particularly significant in affecting aquatic organisms, currently gaining more attentions and sparking discussions. In response to the limitations of traditional detections, fluorescent probes have emerged as a promising solution with some advantages, such as weaker background interference, shorter processing time, higher accuracy. Thus, a novel fluorescent probe, FS-Hg-1, has been developed for assessing mercury ion (Hg2+) concentrations in aquatic products. This probe displays specific recognition of mercury ions in fluorescence spectra. Notably, FS-Hg-1 exhibits a distinct color change to pink when combined with Hg2+ (with a 948-fold increase in absorption at 568 nm) and a substantial fluorescence change towards Hg2+ (361-fold increase, excitation at 562 nm, emission at 594 nm) in N, N-dimethylformamide. The probe boasts a detection limit of 0.14 mu M and rapid reaction with Hg2+ within 10 s, showing an excellent linear correlation with [Hg2+] in the range of 0 to 10 mu M. Through thorough analysis using FS-Hg-1, the results align with those from the standard method (P > 0.05), with spiked recovery rates ranging from 108.4% to 113.2%. With its precise recognition, low detection limit, and remarkable sensitivity, this fluorescent assay proves effective in mercury concentration determination in aquatic samples without interference. The potential of FS-Hg-1 is promising for speedy detection of residual Hg2+ and holds significance in ensuring food safety.

Reactive oxygen species (ROS), a chemically defined group of reactive molecules derived from molecular oxygen, are involved in a variety of physiological and pathological processes, including immune defense, cellular metabolism, and other physiological processes. To access their detailed function in these processes, it is critical to establish rapid, accurate and in situ assays for these species in vivo. Among the potential assays, fluorescent probes are considered as the most promising candidate to monitor the biological ROS in vivo with great spatial and temporal resolution and are extensively used as an excellent tool in modern redox biology discovery. Recently, abundant fluorescent probes have been successively developed for in vitro or intracellular detection of ROS, but most of them could not be used for in vivo imaging due to their intrinsic shortcomings such as short emission wavelengths, phototoxicity and poor tissue penetration. Recent development of fluorescent ROS probes with near-infrared emission aim to address these concerns to develop practical assays. Herein, we review recent developments of ROS-sensitive near-infrared fluorescent probes, with an emphasis on the design, synthesis, characteristics of fluorescent probes, as well as their applications. We hope this review will aid the development of a new generation of efficient, sensitive and biocompatible fluorescent probes for in vivo ROS detection.

Nitric oxide (NO) plays an important role in multiple physiological processes of the body involved in regulation, such as cardiovascular relaxation, neural homeostasis, and immune regulation, etc. The real-time monitoring of NO is of great significance in the investigation of related disease mechanisms and the evaluation of pharmacodynamics. Fluorescent probes are considered as a highly promising approach for pharmaceutical analysis and bioimaging due to their non-invasive character, real-time detection, and high sensitivity. However, there are still some challenges in the determination of biological nitric oxide with fluorescent probes, such as low anti-interference ability, poor function modifiability, and low organ specificity. Therefore, it would be beneficial to develop a new generation of fluorescent probes for real-time bioimaging of NO in vivo after this systematic summary.

As a reactive oxygen species (ROS), excessive production of H2O2 contributes to the development of several diseases such as, inflammation, cancer, and respiratory diseases. Supplementation with endogenous or exoge-nous antioxidants can scavenge ROS and reduce the oxidation of cellular molecules, thus alleviating the gen-eration of diseases. Therefore, the determination of H2O2 content and its antioxidant activity is of great importance in disease diagnosis and treatment. In this paper, a ratiometric SERS sensor with a flexible cellulose membrane was designed for quantitative detection of H2O2 and assessment of antioxidant activity. First, gold seeds were reduced on bacterial cellulose membrane (BCM) and Au NPs were smoothly deposited on the bac-terial cellulose membrane (BCM) using halides to reduce the reduction potential in the growth solution to form a flexible BCM@Au NPs SERS substrate. Afterwards, the oxidation of H2O2 was used to convert 3-mercaptophenyl-boronic acid (3-MPBA) to the corresponding phenol form 3-hydroxyphenylethanol (3-HTP). The change of substance resulted in a good linear relationship between the intensity ratio corresponding to the two Raman shifts of 881 cm-1 and 995 cm-1 and the H2O2 concentration with a detection limit of 0.0186 mu M. This opens up a new method for the detection of H2O2 with high sensitivity and accuracy. In addition, this SERS platform was successfully used for the determination of antioxidant activity. It is promising to be applied to disease diagnosis and efficacy evaluation.

One of the main challenges faced in food safety is the accumulation of toxic heavy metals from environmental sources, which can sequentially endanger human health when they are consumed. It is invaluable to establish a practical assay for the determination of heavy metals for food safety. Among the current detection methods, technology based on fluorescent probes, with the advantages of sensitivity, convenience, accuracy, cost, and reliability, has recently shown pluralistic applications in the food industry, which is significant to ensure food safety. Hence, this review systematically presents the recent progress on novel fluorescent probes in determining heavy metals for food safety over the past five years, according to fluorophores and newly emerging sensing cores, which could contribute to broadening the prospects of fluorescent materials and establishing more practical assays for heavy metal determinations.

A colorimetric and ratiometric fluorescence probe FS-wine with near-infrared emission for rapid detection of sulfites was proposed and developed. In addition, a practical assay for determining residual sulfites (R2 > 0.99) was established with the variation of Em480 nm/Em650 nm (ex. at 410 nm). The assay was effective in detecting sulfites in wine samples with the exclusion of potential interference. The results achieved using FS-wine were consistent with those obtained using the standard method (P > 0.05), with the spiked recovery rate ranging from 99.9% to 110.3%. We also monitored the residual sulfites in the wine samples, which were mainly in the form of HSO3−, indicating that FS-wine could analytically detect HSO3−, SO32−, and S2O52− in derivatives with different linear characterizations. These findings show that FS-wine can be used to detect sulfites in food more than wines.

文章设计合成了 一种新型基于罗丹明B的增强型荧光探针以定性定量检测Cr3+.探针通过1H、13C和LC-MS进行结构表征,利用荧光分光光度法对光谱特性进行研究.结果表明,在乙腈溶液中,探针可选择性识别Cr3+,诱发肉眼可见的颜色变化(从无色变为亮粉色)以及剧烈的荧光开启(81904.30倍).反应时间为4 min,检测限可达0.059 μmol/L.此外,探针在实际样品检测中也表现良好,加标回收率为100.21％～100.69％.

近年,预制菜发展趋势迅猛,随着消费者对食品品质需求逐步提高,食品个性化需求日益突出.文章对大数据进行采集和归纳,分析预制菜的基本发展现状,阐述"反向C2M模式+电商平台+预制菜"模式的构想,提出"群性化定制"逐步发展为"个性化定制"的建议.

A colorimetric and ratiometric fluorescence probe FS-wine with near-infrared emission for rapid detection of sulfites was proposed and developed. It is evident that FS-wine could clarify the uncertain content of sulfites in some colorless or translucent wine within the rapid detection. In addition, a practical assay for determining residual sulfites (R-2 > 0.99) was established with the variation of Em480 nm/Em650 nm (excited at 410 nm). The assay was effective in detecting sulfites in wine samples with the exclusion of potential interference. The results achieved using FS-wine were consistent with those obtained using the standard method (P > 0.05), with the spiked recovery rate ranging from 99.9% to 110.3%. In addition, the dominant residual sulfite could be confirmed as HSO3- in the wine samples with this assay, which was consistent with the interpretation supposed from the native chemical characterization of sulfites. These results affirmed that FS-wine could efficiently detect sulfites in the food to assure food safety when sulfites were used as preservation agent.

Jaboticaba is a tropical plant and its fruit rich in nutrients, volatile compounds, and biological activities, which considered to be an edible health benefits plant. Despite its popularity for fresh consumption, jaboticaba is rarely used in intensive processing in China. The content of nutrients and antioxidant in jaboticaba greatly impacts how it is processed healthy food. In this study, we evaluated the nutrients, antioxidant capacity, and volatile compounds of three jaboticaba cultivars including Sabara, Argentina, and Fukuoka, respectively. Our results revealed each variety has its merits. Sabara had an abundance of volatile compounds, a suitable acid-sugar ratio, and a slightly lower antioxidant capacity, making it suitable for fresh consumption. Argentina is the richest in volatile compounds in ripe fruit, but slightly lighter in taste and acid-sugar ratio, making it suitable for dry products. The large size, juicy flesh, low acid-sugar ratio, and less volatile compounds content of Fukuoka also make it suitable for juice processing. Three cultivars of jaboticaba berry exhibited different characteristics, providing reference evidence for the manufacturing and processing of jaboticaba health food.