Publications by authors named "Pao Li"

Unscrupulous merchants sell the mold-damaged (CRP) after removing the mold. In this study, an accurate and non-destructive strategy was developed for the discrimination of mold-damaged CRPs using portable near-infrared (NIR) spectroscopy and chemometrics. The outer surface and inner surface spectra were obtained without destroying CRPs.

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An automatic, rapid and non-targeted detection method for multi-pesticides in plant-derived foods was developed by gas chromatography-mass spectrometry and chemometrics. In this method, a novel algorithm named moving window iterative target transformation factor analysis was proposed. Although there are challenges of peak overlapping and background interference, the retention time and corrected mass spectra of unknown pesticides can be automatically obtained through iteration calculation in the 'moving window' with reference to the pesticide mass spectral library.

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Regulatory T cells (Tregs) are critical mediators of immune tolerance and play a diametric role in cancer and autoimmunity. Tumor-infiltrating Tregs are often associated with poor prognosis in solid tumors because their enrichment in the tumor microenvironment contributes to immunosuppression. Conversely, dysregulation in the Treg compartment can disrupt self-tolerance, leading to autoimmunity.

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Color is one of the important indicators affecting the quality of fermented pepper sauces, and it is closely related to carotenoid composition. This study systematically analyzed the changes in carotenoids and related physiochemical indices during the fermentation of yellow lantern pepper sauce. The CIELab color values indicated that L* and C* displayed a significant decreasing trend during fermentation.

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Understanding the formation mechanism of the flavor compounds in stinky tofu brine is crucial for controlling the flavor quality of Changsha stinky tofu. Dynamic changes in associated bacteria, enzymes, and differential metabolites in the metabolic pathway of aromatic amino acids in brine were investigated. Results showed that phenol (0.

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An adsorbent-magnetic molecularly imprinted polymers nanoparticles (MMIPs NPs) were synthesized for the extraction of 6-benzylaminopurine (6-BA) using FeO as magnetic core. The MIPs were prepared with methacrylic acid and sodium p-styrene sulfonate as bifunctional monomers. The adsorbents were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffractometer, thermogravimetric analysis and vibrating sample magnetometer.

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There has been no study on using near-infrared spectroscopy (NIRS) to predict the hotness of fresh pepper. This study is aimed at developing a non-destructive and accurate method for determining the hotness of fresh peppers using portable NIRS and the variable selection strategy. Spectra from different locations on samples were obtained non-destructively with a single scan.

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In this paper, a novel strategy of "pick the best of the best" was proposed for the nondestructive identification of different-origin and adulterated Poria cocos with near-infrared spectroscopy. First, various preprocessing methods were divided into three classes: baseline correction, scattering and trend correction, and scaling. The single preprocessing methods with the best predictions in each class were selected.

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The present study investigates volatile organic compound (VOC) compositional changes in Liuyang Douchi during fermentation via a HS-GC-IMS and HS-SPME-GC-MS combination approach. A total of 115 VOCs were identified from Douchi, most of which were accumulated during pile fermentation. Notably, most alcohols and acids decreased with fermentation, while esters, ketones, pyrazines, and phenols accumulated during pile fermentation.

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Chopped pepper is one of the traditional fermented pepper products in China. At present, the industrial production method is mainly to preserve the peppers with high salt about 1 year, and then make the product after desalination and seasoning when it is processed. However, the composition and succession of the bacterial community involved in the long-term preservation of salted pepper was complex.

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The magnetic molecular imprinting polymers nanoparticles (MMIPs NPs) for the extraction of norfloxacin (NOR) were prepared by self-polymerization of dopamine onto the surface of (3-Aminopropyl)triethoxysilane (APTES)-modified FeO NPs. The MMIPs NPs were characterized by FT-IR spectroscopy, XRD, VSM and TEM. The characterization results show that the MMIPs NPs possess superparamagnetic characteristic with the saturated magnetization value of 38.

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The quality of Citri Reticulatae Pericarpium (CRP) is closely correlated with the aging time. However, CRPs in different storage ages are similar in appearance, and the young CRP may be labeled as the aged one to obtain the excess profit by some unscrupulous traders. Most traditional analysis methods are laborious and time-consuming, and they can hardly realize the nondestructive classification.

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This study reports the optimization of culture conditions and medium components of M9, an endophytic strain of Bacillus amyloliquefaciens, which we had previously isolated from kiwifruit, and evaluation of its effect on kiwifruit postharvest protection against soft rot. The method of one-factor-at-a-time was used to determine the optimum culture conditions, and response surface methodology was applied to optimize the medium constituents. After optimization, a high rate of antifungal activity (73.

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A simple and nondestructive method for the analysis of soluble solid content in citrus was established using portable visible to near-infrared spectroscopy (Vis/NIRS) in reflectance mode in combination with appropriate chemometric methods. The spectra were obtained directly by the portable Vis/NIRS without destroying samples. Outlier detection was performed by using leave-one-out cross-validation (LOOCV) with the 3σ criterion, and the calibration models were established by partial least squares (PLS) algorithm.

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Citri Reticulatae Pericarpium (CRP), has been used in China for hundreds of years as a functional food and medicine. However, some short-age CRPs are disguised as long-age CRPs by unscrupulous businessmen in order to obtain higher profits. In this paper, a rapid and nondestructive method for the classification of different-age CRPs was established using portable near infrared spectroscopy (NIRS) in diffuse reflectance mode combination with appropriate chemometric methods.

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This study evaluated the interaction of (CI) flavonoids (luteolin, acacetin, and buddleoside) with α-amylase. Surface plasmon resonance (SPR) assay showed their equilibrium dissociation constants ( ) are 1.9695 ± 0.

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A method is reported for in-situ detection of the antibiotic tetracycline (TC). It is based on a combination of extraction of TC by magnetic molecularly imprinted polymers nanoparticles (MMIPs NPs) and detection by surface plasmon resonance (SPR). The TC-captured MMIPs NPs were flowed over the surface of the SPR chip that was modified with mercaptoethylamine.

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Intensive study of the metabolome during the Douchi fermentation can provide new knowledge for optimizing the fermentation process. In this work, the metabolic characterization throughout the fermentation of Douchi was investigated using gas chromatography with time-of-flight mass spectrometry. A total of 511 peaks were found, and 114 metabolites were identified.

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It is difficult to produce southern stinky tofu, a famous traditional Chinese snack, at industry scale due to the complex composition of its brine. In this study, the fingerprints of organic volatile flavor compounds in the southern stinky tofu brine samples from five manufacturers were studied using headspace solid-phase microextraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS) with the aid of chemometric methods. The fingerprints were obtained by HS-SPME/GC-MS and analyzed with the time shift alignment method, Shannon entropy, correlation coefficient, and principal component analysis.

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This study optimized the headspace solid phase microextraction (HS-SPME) conditions for the analysis of the volatile flavor compounds of Chinese south stinky tofu brine by gas chromatography-mass spectrometry (GC-MS). The optimum HS-SPME conditions established were as follows: polar column CD-WAX, white 85 μm polyella extractor, extraction temperature 60 °C, equilibrium time 20 min, extraction time 40 min. Under these conditions, a total of 63 volatile flavor compounds in five stinky tofu brines were identified.

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Objective: To investigate the effects of different mechanical stretch conditions on the differentiation of rat tendon stem cells (TSCs), to find the best uniaxial cyclic stretching for TSCs tenogenic differentiation, osteogenic differentiation, and adipogenic differentiation.

Methods: TSCs were isolated from the Achilles tendons of 8-week-old male Sprague Dawley rats by enzymatic digestion method and cultured. The TSCs at passage 3 were randomly divided into 5 groups: group A (stretch strength of 4% and frequency of 1 Hz), group B (stretch strength of 4% and frequency of 2 Hz), group C (stretch strength of 8% and frequency of 1 Hz), group D (stretch strength of 8% and frequency of 2 Hz), and group E (static culture).

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Objective: To explore the effect of different intensity treadmill training on the repair of micro-injured Achilles tendon induced by collagenase in rats.

Methods: Seventy-two 8-week-old male Sprague Dawley rats (weighing, 200-250 g) were selected. After adaptive treadmill training for 1 week, rats were injected with 30 μL type I collagenase solution (10 mg/mL) into both Achilles tendons to make micro-injured Achilles tendon models.

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Flavonoids, a class of natural drugs with broad biological activity, exhibit inhibitory effect on α-amylase. Citrus peel is a good source of flavonoids. The real-time interactions between three Citrus flavonoids (naringin, neohesperidin, hesperidin) and α-amylase were investigated by surface plasmon resonance biosensor, and were compared with the α-amylase inhibitors, acarbose.

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Objective: To investigate whether mechanical stretch stimulation affects the expression of the immediate early gene c-fos mRNA in rat Achilles-derived tendon stem cells (TSCs) .

Methods: TSCs were isolated from the Achilles tendons of 8 weeks old male Sprague Dawley rats by enzymatic digestion method and cultured for 3 passages. The TSCs were stimulated by a uniaxial cyclic stretching loading system under the condition of 1 Hz, respectively with 4% or 8% stretch intensity for 0, 5, 15, 30, 60, and 120 minutes.

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In chromatographic analysis of multicomponent real samples, peak overlapping, high level of noise and background are frequently encountered, making the qualitative and quantitative analysis difficult or even impossible. In this work, an algorithm named as generalized window factor analysis (GWFA) was proposed for quantitative analysis of the target components in the samples with complex matrices by gas chromatography-mass spectrometry (GC-MS). The theory and calculation of GWFA are just similar with the conventional window factor analysis (WFA), but the "window" is defined as the selected channels (mass-to-charge ratios) in the mass spectral dimension of the data matrix, instead of a continuous region in chromatographic dimension along the retention time.

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