Screening of a potential probiotic Lactiplantibacillus plantarum NUC08 and its synergistic effects with yogurt starter.

This study aims to identify lactic acid bacteria (LAB) isolates possessing physiological characteristics suitable for use as probiotics in yogurt fermentation. Following acid and bile salt tolerance tests, Lactiplantibacillus plantarum (NUC08 and NUC101), Lacticaseibacillus rhamnosus (NUC55 and NUC201), and Lacticaseibacillus paracasei (NUC159, NUC216, and NUC351) were shortlisted based on intraspecies distribution for further evaluation. Their physiological probiotic properties, including transit tolerance, adhesion, autoaggregation, surface hydrophobicity, biofilm formation, and antibacterial activity, were assessed. Principal component analysis indicated that Lactiplantibacillus plantarum NUC08 was the preferred choice among the evaluated strains. Subsequent investigations revealed that co-culturing Lactiplantibacillus plantarum NUC08 with 2 yogurt starter strains resulted in a cooperative and synergistic effect, enhancing the growth of mixed strains and increasing their tolerance to simulated gastric and intestinal conditions. Additionally, when Vibrio harveyi bioluminescent reporter strain was used, the 3 cocultured strains cooperated to induce the activity of a quorum sensing (QS) molecule autoinducer-2 (AI-2), hinting a potential connection between phenotypic traits and QS in the cocultured strains. Importantly, LAB viable counts were significantly higher in yogurt co-fermented with Lactiplantibacillus plantarum NUC08, consistently throughout the storage period. In conclusion, the study demonstrates that the probiotic strain Lactiplantibacillus plantarum NUC08 can be employed in synergy with yogurt starter strains, affirming its potential for use in the development of functional fermented dairy products.

Molecular mechanisms of cadmium-induced cytotoxicity in human ovarian granulosa cells identified using integrated omics.

Epidemiological and clinical data have demonstrated that exposure to cadmium (Cd), a toxic heavy metal, is associated with an increased risk of female infertility. Granulosa cells, the main somatic cells comprising ovarian follicles, are one of the main targets of Cd in the ovaries. However, the mechanism by which Cd induces cytotoxicity in granulosa cells has not been fully elucidated. In this study, we exposed human ovarian granulosa cells (KGN cells) to Cd and conducted in vitro cell experiments and multi-omics (metabolomics and transcriptomics) methods to elucidate these mechanisms. Cd exposure was found to not only induce the apoptosis of the KGN cells but also further reduced mitochondrial function by decreasing mitochondrial membrane potential, ATP production, and respiratory chain complex activity as well as increasing mitochondrial reactive oxygen species (ROS) production. A total of 443 differentially expressed metabolites (160 upregulated and 283 downregulated) and 5200 differentially expressed genes (4634 upregulated and 566 downregulated) were observed in the Cd exposed-cells. The multi-omics data showed that Cd interfered with citric acid cycle (TCA cycle), amino acid (including alanine, glycine, serine, threonine, arginine, and proline) metabolism, and calcium signaling. These findings help to better elucidate the potential toxicity mechanisms of Cd on granulosa cells and the ovary.

Separation techniques for manufacturing fruit spirits: From traditional distillation to advanced pervaporation process.

Separation process is one of the key processes in the production of fruit spirits, including the traditional distillation method and the new pervaporation membrane method. The separation process significantly determines the constituents and proportions of compounds in the fruit spirit, which has a significant impact on the spirit quality and consumer acceptance. Therefore, it is important and complex to reveal the changing rules of chemical substances and the principles behind them during the separation process of fruit spirits. This review summarized the traditional separation methods commonly used in fruit spirits, covering the types, principles, and corresponding equipment of distillation methods, focused on the enrichment or removal of aroma compounds and harmful factors in fruit spirits by distillation methods, and tried to explain the mechanism behind it. It also proposed a new separation technology for the production of fruit spirits, pervaporation membrane technology, summarized its working principle, operation, working parameters, and application in the production of fruit spirits, and outlined the impact of the separation method on the production of fruit spirits based on existing research, focusing on the separation of flavor compounds, sensory qualities, and hazard factors in fruit spirits, along with a preliminary comparison with distillation. Finally, according to the current researches of the separation methods and the development requirement of the separation process of fruit spirits, the prospect of corresponding research is put forward, in order to propose new ideas and development directions for the research in this field.

Identification of regionalmarkers based on the flavor molecular matrix analysis of sauce-aroma style baijiu.

BACKGROUND: Baijiu is a very complex system and its flavor substances are endogenous, influenced by raw materials, starter, production process, production region and other factors. The production region directly affects the composition of flavor substances and quality of baijiu. However, identification of baijiu region is challenging because the corresponding relationship between the production region and baijiu quality is not clear, and the identification of regionalmarkers is indeterminate. In this study, the differences in volatile components of sauce-aroma style baijiu from four representative regions were investigated. RESULTS: A total of 94 volatile compounds were identified in samples tested. Additionally, it was verified that 35 potential flavor substances had important contributions to the aroma of sauce-aroma style baijiu. Meanwhile, nine potential regionalmarkers were screened through multivariate analysis. Further, based on distribution of volatile compounds and the results of sensory evaluation combined with multivariate analysis, a molecular matrix and correlation network were established according to the results of addition experiments, which showed that six substances had a significant impact on the flavor of the tested samples. CONCLUSION: Six key flavor substances (ethyl octanoate, ethyl 2-methylpropanoate, propyl acetate, ethyl heptanoate, 2-nonanone and butyl hexanoate) were considered as important regionalmarkers to effectively identify the production region of sauce-aroma style baijiu. © 2023 Society of Chemical Industry.

Human ectopic olfactory receptors and their food originated ligands: a review.

Ectopic olfactory receptors (EORs) are expressed in non-nasal tissues of human body. They belong to the G-protein coupled receptor (GPCR) superfamily. EORs may not be capable of differentiating odorants as nasal olfactory receptors (ORs), but still can be triggered by odorants and are involved in different biological processes such as anti-inflammation, energy metabolism, apoptosis etc. Consumption of strong flavored foods like celery, oranges, onions, and spices, is a good aid to attenuate inflammation and boost our immune system. During the digestion of these foods in human digestive system and the metabolization by gut microbiota, the odorants closely interacting with EORs, may play important roles in various bio-functions like serotonin release, appetite regulation etc., and ultimately impact health and diseases. Thus, EORs could be a potential target linking the ligands from food and their bioactivities. There have been related studies in different research fields of medicine and physiology, but still no systematic food oriented review. Our review portrays that EORs could be a potential target for functional food development. In this review, we summarized the EORs found in human tissues, their impacts on health and disease, ligands interacting with EORs exerting specific biological effects, and the mechanisms involved.

CRISPR-/Cas12a-Mediated Liposome-Amplified Strategy for the Surface-Enhanced Raman Scattering and Naked-Eye Detection of Nucleic Acid and Application to Food Authenticity Screening.

Surface-enhanced Raman scattering (SERS) has been recognized as a powerful tool for biosensors due to the ultrahigh sensitivity and unique fingerprint information. However, there are some limitations in trace target nucleic acid detection for the restricted signal-transducing and amplification strategies. Inspired by CRISPR/Cas12a with specific target DNA-activated collateral single-strand DNA (ssDNA) cleavage activity and liposome with signal molecule-loading properties, we first proposed a sensitive SERS-based on-site nucleic acid detection strategy mediated by CRISPR/Cas12a with trans-cleavage activity on ssDNA linkers utilized to capture liposomes. Liposomes loading two kinds of signal molecules, 4-nitrothiophenol (4-NTP) and cysteine, could achieve the dual-mode detection of target DNA with SERS and naked eye, respectively. The promptly amplified signals were initiated by the triggered breakdown of signal molecule-loaded liposomes. Emancipated 4-NTP, a biological-silent Raman reporter, would achieve highly selective and sensitive SERS measurement. Released cysteine induced the aggregation of plasmonic gold nanoparticles, leading to an obvious red to blue colorimetric shift to realize portable naked-eye detection. With this strategy, target nucleic acid concentration was dexterously converted into SERS and visualization signals and could be detected as low as 100 aM and 10 pM, respectively. The approach was also successfully applied to determine meat adulteration, achieving the detection of a low adulteration ratio in the complicated food matrix. We anticipate that this strategy will not only be regarded as a universal platform for the on-site detection of food authenticity but also broaden SERS application for the accurate determination of diverse biomarkers.

Cadmium induces apoptosis of human granulosa cell line KGN via mitochondrial dysfunction-mediated pathways.

Cadmium (Cd) is an important industrial and environmental pollutant, which is closely correlated with female infertility. Although Cd-induced developmental disorders of human ovarian follicles have been widely reported, the underlying mechanisms remain not fully elucidated. In this study, we explored the mechanism underlying Cd-triggered apoptosis in granulosa cells. Following the treatment with various levels of Cd (0, 0.625, 1.25, 2.5 and 5 µM), we found that Cd triggered the death of KGN cells (a human granulosa-like tumor cell line) in a dose- as well as time-dependent manner. The levels of expressions of Bax and Bak were significantly increased, whereas the expression levels of Mcl-1 and Bcl-2 were considerably decreased after being treated with high levels of Cd. We showed that Cd exposure remarkably triggered mitochondrial dysfunction, including increased intracellular ROS and free Ca2+ levels, and decreased ATP generation and mitochondrial membrane potential. Furthermore, we found that mitochondrial dysfunction, especially excessive ROS production and intracellular Ca2+ overload, serve a vital role in Cd-triggered apoptosis of KGN cells. After using inhibitors to block the corresponding signaling cascades, Cd-mediated apoptosis was markedly repressed by ASK1 and p38 inhibitors in contrast with the control group. This suggests the activation of downstream pathways triggered by mitochondrial dysfunction participates in granulosa cell death and may cause female reproductive toxicity after Cd exposure.

Bisphenol A induces apoptosis through GPER-dependent activation of the ROS/Ca2+-ASK1-JNK pathway in human granulosa cell line KGN.

Bisphenol A (BPA) is widely distributed in the environment and human surroundings and is closely related to the occurrence of many chronic diseases including female infertility. Although BPA-induced granulosa cell apoptosis has been widely reported, the underlying mechanisms remain unknown. In this study, we evaluated the induction effect of BPA exposure on apoptosis and mechanisms of regulation in KGN cells (a human granulosa-like tumor cell line). Our results indicated that BPA induced apoptosis of KGN cells in a dose- and time-dependent manner. BPA exposure significantly promoted the expression of pro-apoptotic proteins and decreased mitochondrial membrane potential. We also observed that high concentrations of BPA significantly promoted the generation of reactive oxygen species (ROS) and calcium ion (Ca2+) accumulation. The involvement of ROS and Ca2+ in BPA-induced KGN cell apoptosis was confirmed by pretreatment with NAC (an antioxidant) and BAPTA-AM (a calcium chelator). After inhibitors pretreatment to block the corresponding signaling pathways, it was found that BPA-induced phosphorylation of JNK and ASK1 proteins and apoptosis of KGN cells were significantly inhibited. We pretreated with G15 (a GPER inhibitor) and found that BPA-induced ROS generation and Ca2+ accumulation and apoptosis were significantly inhibited. These results suggest that BPA exposure induces KGN cell apoptosis through GPER-dependent activation of the ROS/Ca2+-ASK1-JNK signaling pathway. Our study provides mechanisms by which BPA induced apoptosis of granulosa cells and ovarian dysfunction.

Multifiber solid-phase microextraction using different molecularly imprinted coatings for simultaneous selective extraction and sensitive determination of organophosphorus pesticides.

Three types of molecularly imprinted solid-phase microextraction fibers were fabricated through sol-gel method using diazinon, parathion-methyl, and isocarbophos as templates, respectively, and assembled together to construct a multifiber for analysis of organophosphorus pesticides in complex matrices. The multifiber provided large extraction capacity and high imprinting factor up to 3.89. In contrast, the imprinting factor of a single fiber was around 1.6, and the multi-template imprinted coating showed no selectivity. The multifiber was applied to analyze pesticides in fruits and vegetables. The limits of detection, which ranged from 0.0052 to 0.23 µg/kg, were lower than those obtained by a single molecularly imprinted fiber, and much lower than those reported by other methods. The recoveries of five analytes in spiked apple, cucumber, Chinese cabbage, and cherry tomato samples were 75.1-123.2%. The study shows that the molecularly imprinted multifiber could achieve simultaneous selective extraction and sensitive determination of multiple targets in complex matrices for high-throughput analysis.

A fluorescent nanoprobe for 4-ethylguaiacol based on the use of a molecularly imprinted polymer doped with a covalent organic framework grafted onto carbon nanodots.

An efficient and rapid fluorescent nanoprobe is described for the determination of the aroma compound 4-ethylguaiacol (4-EG). A molecularly imprinted polymer was doped with a covalent organic framework (COF) grafted onto carbon nanodots that was prepared by one-pot reverse microemulsion polymerization. Amino groups at the surface of carbon nanodots coordinate to the COFs to produce a strong bond and this warrants thermal and chemical stability of the probe. Remaining free amino groups interact with the phenolic hydroxyl groups of 4-EG through acid-base pairing interactions. The probe, with excitation/emission maxima at 350/440 nm, responds to 4-EG due to the charge transfer to the carbon nanodots. Under optimized conditions, fluorescence drops linearly as the concentrations of 4-EG increase from 0.025 to 1 µg mL-1, with a detection limit of 17 ng mL-1. The probe was applied to the determination of 4-ethylguaiacol in Chinese Baijiu and wine samples after pretreatment by a single dilution step. The recoveries of spiked samples ranged from 78.4to 110.1%. Graphical abstract Schematic presentation of the synthesis of a fluorescent nanoprobe based on molecularly imprinted polymers doped with covalent organic framework grafted onto carbon nanodots. It was used as an efficient and rapid nanoprobe for 4-ethylguaiacol detection with high selectivity and sensitivity.

In Situ Real-Time Tracing of Organophosphorus Pesticides in Apples by Solid-Phase Microextraction with Developed Sampling-Rate Calibration.

An in situ tracing study based on solid-phase microextraction (SPME) was conducted to investigate the uptake and elimination of organophosphorus pesticides in apples. A matrix-compatible polydimethylsiloxane/poly(styrene-co-divinylbenzene)/polydimethylsiloxane fiber was produced to meet the needs of in situ sampling. The fiber had high extraction ability, good sensitivity and accuracy with respect to the analytes in apple pulp, and could be used 85 times. Although the sampling rate was changing over time, quantification was still achieved by the sampling rate calibration method. Some factors that affect its applicability were studied. The limits of detection were 0.18 ng/g for diazinon and 0.20 ng/g for chlorpyrifos, rather lower than the maximum residue limits of the National Food Safety Standard of China (GB 2763-2016) and the European Commission (Reg.(EU) No 834/2013, 2018/686). The accuracy of in situ SPME quantification was verified by comparing with the results obtained by the traditional liquid-liquid extraction method. In this work, the in situ sampling method is developed using apples, diazinon, and chlorpyrifos as a model system; however, this method can be used for in vivo analysis of fruits and vegetables for nutrition and safety monitoring.

Interactions between p-Cresol and Ala-Lys-Arg-Ala (AKRA) from Sesame-Flavor-Type Baijiu.

The objective of this study was to investigate the influence of Ala-Lys-Arg-Ala (AKRA), a tetrapeptide newly identified from Chinese Sesame flavor-type Baijiu in our previous work, on its binding ability with aroma compounds. A method using headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC/MS) was employed to determine the corresponding binding ability between different concentrations of AKRA (10 - 1000 µg/L) and aromas in Baijiu. In comparison, the aroma molecules in Baijiu before and after adding AKRA were almost the same; only their volatility was altered, with mostly the esters, alcohols, and phenolic compounds being decreased. Additionally, AKRA slightly changed the whole aroma profile of Baijiu, especially with respect to p-cresol (an off-odor in sesame-flavor-type Baijiu), which was verified by systematic sensory experiments including gas chromatography-olfactometry (GC-O) and odor activity values (OAVs) analysis. The nonvolatile tetrapeptide favored the hydrogen bond interactions with p-cresol, forming the AKRA- p-cresol complex, thus reducing the headspace concentration of phenolic off-flavors as evidenced by HS-SPME-GC/MS, ultraviolet (UV) absorption spectroscopy, and nuclear magnetic resonance spectrum (1H NMR) analysis. Meanwhile, the hydrogen bond interaction was further confirmed with the intermolecular cross-peaks between the carboxyl hydrogen of AKRA and the phenolic hydroxyl of p-cresol by nuclear Overhauser effect spectroscopy (1H-1H NOESY).

The Occurrence of Propyl Lactate in Chinese Baijius (Chinese Liquors) Detected by Direct Injection Coupled with Gas Chromatography-Mass Spectrometry.

As one of the oldest distillates in the world, flavor compounds of Chinese Baijiu (Chinese liquor) were extremely complex. Propyl lactate was firstly detected by direct injection and gas chromatography-mass spectrometry (GC-MS) in 72 Chinese Baijius. The objectives were to detect the contents of propyl lactate and evaluate its contribution to the aroma of Chinese Baijiu based on odor activity values (OAVs). The levels of propyl lactate in these distillates were determined by internal standard method and selective ion monitoring (SIM), which ranged from 0.050 to 1.900 mg∙L(-1) under investigation. Its detection threshold was determined by Three-Alternative Forced-Choice (3-AFC) and curve fitting (CF), which was 0.740 mg∙L(-1) in 38% ethanol solution. The contribution of propyl lactate on the aroma of these distillate drinks was evaluated by their odor activity values (OAVs), which varied from 0.066 to 4.440. The OAVs of propyl lactate were found to exceed 1 in 13 Chinese Baijius, including 50° Jingzhi Guniang 5 years (4.440), 52° Jingzhi Guniang 10 years (3.024), Jingyanggang (2.568), Xianghe Ronghe Shaofang (2.313), and 1956 Laolang (1.431), which indicated that propyl lactate was one of odor-active components in these Chinese Baijius.

Preparation of reusable hydrogel spheres based on sodium alginate/Fe3O4 modified with carboxymethyl Huangshui polysaccharide and the efficient adsorption performance for methylene blue.

This study successfully constructed a novel multifunctional bio-adsorbent using sodium alginate (SA), ferroferric oxide (FFO), and carboxymethyl Huangshui polysaccharide (CMHSP) with rapid separation, pH sensitivity, efficient adsorption, and reusability for enhancing the removal of methylene blue (MB) in wastewater. FTIR, XRD, SEM, and VSM results indicated CMHSP improved the porosity of the hydrogel spheres, thus significantly enhancing the MB adsorption capacity with the rate-limiting controlled by chemical adsorption, intraparticle diffusion, and film diffusion. The maximum adsorption capacity obtained from Langmuir model of SA-FFO-CMHSP (186.57 mg/g) was obviously higher than that of SA-FFO (178.82 mg/g). Thermodynamic results showed that the MB adsorption process was endothermic, spontaneous, and favorable, and physical adsorption was dominant. Remarkably, MB adsorption maintained 87% ∼ 95% of the initial after four adsorption-desorption cycles, and proper carboxymethylation was conducive to MB adsorption over a broader range pH. These findings provided reference for designing new efficient bio-adsorbents and the recyclable utilization of Huangshui by-products, which was of great value.

Bisphenol A and its structural analogues exhibit differential potential to induce mitochondrial dysfunction and apoptosis in human granulosa cells.

Bisphenol A (BPA) is an endocrine disruptor strongly associated with ovarian dysfunction. BPA is being substituted by structurally similar chemicals, such as bisphenol S (BPS), bisphenol F (BPF), and bisphenol AF (BPAF). However, the toxicity of these analogues in female reproduction remains largely unknown. This study evaluated the effects of BPA and its analogues BPS, BPF, and BPAF on the mitochondrial mass and function, oxidative stress, and their potential to induce apoptosis of human granulosa cells (KGN cells). BPA and its analogues, especially BPA and BPAF, significantly decreased mitochondrial activity and cell viability. The potential of bisphenols to reduce mitochondrial mass and function differed in the following order: BPAF > BPA > BPF > BPS. Flow cytometry revealed that exposure to bisphenols significantly increased mitochondrial ROS levels and increased mitochondrial Ca2+ levels. Thus, bisphenols exposure causes mitochondrial stress in KGN cells. At the same time, bisphenols exposure significantly induced apoptosis. These results thus emphasize the toxicity of these bisphenols to cells. Our study suggests the action mechanism of BPA and its analogues in damage caused to ovarian granulosa cells. Additionally, these novel analogues may be regrettable substitutes, and the biological effects and potential risks of BPA alternatives must be evaluated.

Preparation, Structural Analysis, and Intestinal Probiotic Properties of a Novel Oligosaccharide from Enzymatic Degradation of Huangshui Polysaccharide.

Huangshui polysaccharide (HSP) has attracted more and more interest due to its potential health benefits. Despite being an excellent source for the preparation of oligosaccharides, there are currently no relevant research reports on HSP. In the present study, a novel oligosaccharide (HSO) with a molecular weight of 1791 Da and a degree of polymerization of 11 was prepared through enzymatic degradation of crude HSP (cHSP). Methylation and NMR analyses revealed that the main chain of HSO was (1 → 4)-α-d-glucose with two O-6-linked branched chains. Morphological observations indicated that HSO exhibited smooth surface with lamellar and filamentary structure, and the glycan size ranged from 0.03 to 0.20 µm. Notably, HSO significantly promoted the proliferation of Bifidobacterium, Bacteroides, and Phascolarctobacterium, thereby making positive alterations in intestinal microbiota composition. Moreover, HSO markedly increased the content of short-chain fatty acids during in vitro fermentation. Metabolomics analysis illustrated the important metabolic pathways primarily involving glucose metabolism, amino acid metabolism, and fatty acid metabolism.

Based on metabolomics, chemometrics, and modern separation omics: Identifying key in-pathway and out-pathway points for pesticide residues during solid-state fermentation of baijiu.

By collecting real samples throughout the entire production process and employing chemometrics, metabolomics, and modern separation omic techniques, it unveiled the patterns of pesticide transfer during solid-state fermentation. The results indicated that 12 types of pesticide residues were prevalent during baijiu production, with organochlorine and carbamate pesticides being the most abundant in raw materials. After fermentation, organochlorine pesticides and pyrethroid pesticides exhibited higher content, while carbamate pesticides dominated in the final product. The pathways for pesticide input and elimination were identified, and the intricate mechanisms underlying these changes were further elucidated. Additionally, key control points were defined to facilitate targeted monitoring. The results indicated that pesticide residue primarily originates from raw materials and Daqu, whereas both solid-state fermentation and distillation processes were effective in reducing pesticide residues. The study offers valuable guidance for establishing pesticide residue standards in the context of baijiu production.

Using GC-O-MS, GC-IMS, and chemometrics to investigate flavor component succession regularity in the Niulanshan Erguotou Baijiu brewing process.

The volatile compounds in Dacha liquor (DL) and Ercha liquor (EL) from Niulanshan Erguotou Baijiu (NEB) were analyzed. The results demonstrated that a total of 34 odorants were identified. For the first time, the products of different brewing stages were analyzed using temperature-programmed headspace gas chromatography-ion mobility spectrometry (TP-HS-GC-IMS). The 3D fingerprint obtained revealed that the compounds exhibited different change patterns during the brewing process. Furthermore, the results of principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) revealed that hexanal, 3-hydroxy-2-butanone, trans-2-pentenal, and ethyl hexanoate could be used to distinguish different types of fermented grains; and hexanal, 1-pentanol, methyl isovalerate, isoamyl acetate, 3-hydroxy-2-butanone, ethyl hexanoate, ethyl acetate, ethyl 2-methylbutanoate, and ethyl pentanoate could be used to distinguish different types of distilled spirits. This study serves as a useful reference for enhancing quality control measures in the production of NEB.

Rapid, simple, and simultaneous electrochemical determination of cadmium, copper, and lead in Baijiu using a novel covalent organic framework based nanocomposite.

It is of great significance to develop a simple and rapid electrochemical sensor for simultaneous determination of heavy metal ions (HMIs) in Baijiu by using new nanomaterials. Here, graphene (GR) was utilized to combine with covalent organic frameworks (COFs) that was synthesized via the aldehyde-amine condensation between 2, 5-dimethoxyterephthalaldehyde (DMTP) and 1, 3, 5-tris(4-aminophenyl) benzene (TAPB) to prepare a new GR/COFDPTB/GCE sensor for electrochemical sensing multiple HMIs. Compared with the glass carbon electrode (GCE), GR/GCE and COFDPTB/GCE, the developed sensor exhibited excellent electrochemical analysis ability for the simultaneous detection of Cd2+, Pb2+, and Cu2+ owing to the synergistically increased the specific surface area, the periodic porous network and plenty of effective binding sites, as well as the enhanced conductivity. Under the optimized experimental parameters, the proposed sensor showed good linearity range of 0.1-25 µM for Cd2+, and both 0.1-11 µM for Pb2+ and Cu2+ with the detection limits of Cd2+, Pb2+, and Cu2+ being 0.011 µM, 8.747 nM, and 6.373 nM, respectively. Besides, the designed sensor was successfully applied to the simultaneous detection of the three HMIs in Baijiu samples, suggesting its good practical application performance and a new method for the rapid detection of HMIs being expended.

Optimisation and characterisation of KOH-activated carbon obtained from Baijiu spent grains for the mitigation of risk factors in alcoholic beverages.

This study aims to repurpose waste grain from the Baijiu brewing process into activated carbon for mitigating risk factors in alcoholic beverages, enhancing quality and ensuring safety. For attaining the most effective activated carbon, tailored carbon synthesis conditions were identified for diverse alcoholic beverages, optimising strategies. For beverages with low flavour compound content, optimal conditions include 900 °C calcination, 16-hour activation and a 1:2 activation ratio. In contrast, for those with abundant flavour compounds, 800 °C calcination, 16-hour activation and a 1:1 activation ratio are recommended. Post-synthesis analyses, employing nitrogen physisorption-desorption isotherms, FT-IR and SEM, validated a significant BET surface area of 244.871 m2/g for the KOH-activated carbon. Critical to adsorption efficiency, calcination temperature showcased noteworthy micro-porosity (0.8-1 nm), selectively adsorbing higher alcohols (C3-C6) and acetaldehyde while minimising acid and ester adsorption. Sensory evaluations refined optimal parameters, ensuring efficient spent grain management and heightened beverage safety without compromising aroma.