1.The Diversity of Filamentous Morphologies and Magnetic Sensitivity Modulated by Diverse MagR Expression in Bacteria
Ya-Fei CHANG ; Jing ZHANG ; Peng ZHANG ; Xiu-Juan ZHOU ; Meng-Ke WEI ; Tian-Tian CAI ; Pei-Qi HE ; Jun-Feng WANG ; Can XIE
Progress in Biochemistry and Biophysics 2026;53(5):1439-1456
Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe2+), whereas clMagR favors ferric iron (Fe3+) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe2+-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe2+/Fe3+ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.
2.The Diversity of Filamentous Morphologies and Magnetic Sensitivity Modulated by Diverse MagR Expression in Bacteria
Ya-Fei CHANG ; Jing ZHANG ; Peng ZHANG ; Xiu-Juan ZHOU ; Meng-Ke WEI ; Tian-Tian CAI ; Pei-Qi HE ; Jun-Feng WANG ; Can XIE
Progress in Biochemistry and Biophysics 2026;53(5):1439-1456
Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe2+), whereas clMagR favors ferric iron (Fe3+) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe2+-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe2+/Fe3+ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.
3.Yougui Pills inhibit oxidative stress-induced damage of granulosa cells by regulating Keap1/Nrf2 signaling pathway via Serpina3k.
Bei-Bei JIAO ; Tian LI ; Bei-Bei ZHOU ; Si CHEN ; Yue CHEN ; Jian ZHANG ; Pei-Juan WANG
China Journal of Chinese Materia Medica 2025;50(4):1111-1120
To investigate the effects and mechanisms of Yougui Pills(YGP) on oxidative damage induced by hydrogen peroxide(H_2O_2) in human ovarian granulosa cells(KGN). The components in serum with low-and high-doses of YGP were analyzed and compared through ultra-high performance liquid chromatography-quadrupole electrostatic field orbitrap mass spectrometry(UHPLC-QEMS), and selected the serum containing YGP high-dose group to follow-up experiments. To stimulated KGN with 200 μmol·L~(-1) H_2O_2to establish an oxidative damage model, which was divided into normal group, model group, low-, medium-, and high-dose of YGP groups, and the efficacy was further verified on the basis of silencing or overexpressing serine protease inhibitor(Serpina3k), further validating the efficacy based on the silencing or overexpression of Serpina3k. TUNEL staining was used to detect cell apoptosis,enzyme-linked immunosorbent assay(ELISA) was employed to measure the secretion levels of estradiol(E_2) and 17β-E_2 in KGN, and Western blot was utilized to assess the expression of Serpina3k and proteins related to the Keap1/Nrf2 signaling pathway. The results show that compared to the model group, each dose group of YGP not only significantly reduces granulocyte apoptosis and upregulates the secretion levels of E_2 and 17β-E_2, but also significantly upregulates Serpina3k and Nrf2 pathway. Further research has found that overexpression of Serpina3k not only enhances the therapeutic effect of YGP but also increases the expression of Nrf2 and inhibits the expression of Keap1. Conversely, interfering with Serpina3k partially reverses the therapeutic effect of YGP, while also partially. The results indicate that the mechanism by which YGP improves oxidative stress in KGN may be related to its upregulation of Serpina3k expression, which affects the conduction of the Keap1/Nrf2 signaling pathway. This study reveals the mechanism by which YGP protects granular cells, providing a certain theoretical basis for its clinical application.
NF-E2-Related Factor 2/genetics*
;
Kelch-Like ECH-Associated Protein 1/genetics*
;
Humans
;
Female
;
Signal Transduction/drug effects*
;
Oxidative Stress/drug effects*
;
Granulosa Cells/cytology*
;
Drugs, Chinese Herbal/pharmacology*
;
Apoptosis/drug effects*
;
Serpins/genetics*
4.Evolution-guided design of mini-protein for high-contrast in vivo imaging.
Nongyu HUANG ; Yang CAO ; Guangjun XIONG ; Suwen CHEN ; Juan CHENG ; Yifan ZHOU ; Chengxin ZHANG ; Xiaoqiong WEI ; Wenling WU ; Yawen HU ; Pei ZHOU ; Guolin LI ; Fulei ZHAO ; Fanlian ZENG ; Xiaoyan WANG ; Jiadong YU ; Chengcheng YUE ; Xinai CUI ; Kaijun CUI ; Huawei CAI ; Yuquan WEI ; Yang ZHANG ; Jiong LI
Acta Pharmaceutica Sinica B 2025;15(10):5327-5345
Traditional development of small protein scaffolds has relied on display technologies and mutation-based engineering, which limit sequence and functional diversity, thereby constraining their therapeutic and application potential. Protein design tools have significantly advanced the creation of novel protein sequences, structures, and functions. However, further improvements in design strategies are still needed to more efficiently optimize the functional performance of protein-based drugs and enhance their druggability. Here, we extended an evolution-based design protocol to create a novel minibinder, BindHer, against the human epidermal growth factor receptor 2 (HER2). It not only exhibits super stability and binding selectivity but also demonstrates remarkable properties in tissue specificity. Radiolabeling experiments with 99mTc, 68Ga, and 18F revealed that BindHer efficiently targets tumors in HER2-positive breast cancer mouse models, with minimal nonspecific liver absorption, outperforming scaffolds designed through traditional engineering. These findings highlight a new rational approach to automated protein design, offering significant potential for large-scale applications in therapeutic mini-protein development.
5.Accurate Machine Learning-based Monitoring of Anesthesia Depth with EEG Recording.
Zhiyi TU ; Yuehan ZHANG ; Xueyang LV ; Yanyan WANG ; Tingting ZHANG ; Juan WANG ; Xinren YU ; Pei CHEN ; Suocheng PANG ; Shengtian LI ; Xiongjie YU ; Xuan ZHAO
Neuroscience Bulletin 2025;41(3):449-460
General anesthesia, pivotal for surgical procedures, requires precise depth monitoring to mitigate risks ranging from intraoperative awareness to postoperative cognitive impairments. Traditional assessment methods, relying on physiological indicators or behavioral responses, fall short of accurately capturing the nuanced states of unconsciousness. This study introduces a machine learning-based approach to decode anesthesia depth, leveraging EEG data across different anesthesia states induced by propofol and esketamine in rats. Our findings demonstrate the model's robust predictive accuracy, underscored by a novel intra-subject dataset partitioning and a 5-fold cross-validation method. The research diverges from conventional monitoring by utilizing anesthetic infusion rates as objective indicators of anesthesia states, highlighting distinct EEG patterns and enhancing prediction accuracy. Moreover, the model's ability to generalize across individuals suggests its potential for broad clinical application, distinguishing between anesthetic agents and their depths. Despite relying on rat EEG data, which poses questions about real-world applicability, our approach marks a significant advance in anesthesia monitoring.
Animals
;
Machine Learning
;
Electroencephalography/methods*
;
Ketamine/administration & dosage*
;
Rats
;
Male
;
Propofol/administration & dosage*
;
Rats, Sprague-Dawley
;
Anesthesia, General/methods*
;
Brain/physiology*
;
Intraoperative Neurophysiological Monitoring/methods*
6.Hippocampal Extracellular Matrix Protein Laminin β1 Regulates Neuropathic Pain and Pain-Related Cognitive Impairment.
Ying-Chun LI ; Pei-Yang LIU ; Hai-Tao LI ; Shuai WANG ; Yun-Xin SHI ; Zhen-Zhen LI ; Wen-Guang CHU ; Xia LI ; Wan-Neng LIU ; Xing-Xing ZHENG ; Fei WANG ; Wen-Juan HAN ; Jie ZHANG ; Sheng-Xi WU ; Rou-Gang XIE ; Ceng LUO
Neuroscience Bulletin 2025;41(12):2127-2147
Patients suffering from nerve injury often experience exacerbated pain responses and complain of memory deficits. The dorsal hippocampus (dHPC), a well-defined region responsible for learning and memory, displays maladaptive plasticity upon injury, which is assumed to underlie pain hypersensitivity and cognitive deficits. However, much attention has thus far been paid to intracellular mechanisms of plasticity rather than extracellular alterations that might trigger and facilitate intracellular changes. Emerging evidence has shown that nerve injury alters the microarchitecture of the extracellular matrix (ECM) and decreases ECM rigidity in the dHPC. Despite this, it remains elusive which element of the ECM in the dHPC is affected and how it contributes to neuropathic pain and comorbid cognitive deficits. Laminin, a key element of the ECM, consists of α-, β-, and γ-chains and has been implicated in several pathophysiological processes. Here, we showed that peripheral nerve injury downregulates laminin β1 (LAMB1) in the dHPC. Silencing of hippocampal LAMB1 exacerbates pain sensitivity and induces cognitive dysfunction. Further mechanistic analysis revealed that loss of hippocampal LAMB1 causes dysregulated Src/NR2A signaling cascades via interaction with integrin β1, leading to decreased Ca2+ levels in pyramidal neurons, which in turn orchestrates structural and functional plasticity and eventually results in exaggerated pain responses and cognitive deficits. In this study, we shed new light on the functional capability of hippocampal ECM LAMB1 in the modulation of neuropathic pain and comorbid cognitive deficits, and reveal a mechanism that conveys extracellular alterations to intracellular plasticity. Moreover, we identified hippocampal LAMB1/integrin β1 signaling as a potential therapeutic target for the treatment of neuropathic pain and related memory loss.
Animals
;
Laminin/genetics*
;
Hippocampus/metabolism*
;
Neuralgia/metabolism*
;
Cognitive Dysfunction/etiology*
;
Male
;
Peripheral Nerve Injuries/metabolism*
;
Extracellular Matrix/metabolism*
;
Integrin beta1/metabolism*
;
Pyramidal Cells/metabolism*
;
Signal Transduction
7.Alterations in striatal functional connectivity in schizophrenia patients with predominant negative symptoms
Yao ZHNAG ; Qin-yu LYU ; Xin-xin HUANG ; Chong-ze WANG ; Qi YAN ; Pei-juan WANG ; Zheng-hui YI
Fudan University Journal of Medical Sciences 2025;52(4):492-499
(rsFC)and their relationship with negative symptoms in schizophrenia patients with predominant negative symptoms(PNS).Methods Fifty-four schizophrenia patients with PNS and sixty-one healthy controls underwent resting-state functional magnetic resonance imaging(fMRI)scans.Data were collected on general demographic information,the Positive and Negative Syndrome Scale(PANSS),the Scale for the Assessment of Negative Symptoms(SANS),and the Temporal Experience of Pleasure Scale(TEPS).Twelve striatal subregions were selected as regions of interest(ROIs)to analyze the rsFC between each ROI and whole-brain voxels.The rsFC values of areas with significant differences were extracted for Pearson correlation analysis with negative symptoms.Results Compared with healthy controls,schizophrenia patients with PNS exhibited decreased rsFC between the right dorsal caudal putamen(DCP)and right insula,left middle frontal gyrus(MFG),right median cingulate and paracingulate gyri(MCC);between the left DCP and right putamen,left insula,left MFG;between the right dorsal rostral putamen(DRP)and bilateral MFG,left insula,right MCC;between the left DRP and right insula,left rolandic operculum;between the right ventral rostral putamen(VRP)and bilateral putamen,left MFG,right MCC;between the left VRP and right insula,left putamen,bilateral MFG,right MCC,left inferior parietal gyrus,excluding supramarginal and angular gyri.Decreased rsFC was also observed between the left ventral caudate/nucleus accumbens(inferior)and right insula,left anterior cingulate cortex,supracallosal,bilateral precuneus(a threshold of P<0.001 in voxel-level with P<0.05 in cluster-lever,corrected for family-wise error,PFWE<0.05/12=0.004).No regions showed increased rsFC in schizophrenia patients with PNS relative to healthy controls.And no significant correlations were found between striatal rsFC and negative symptoms(PBonferroni>0.05).Conclusion Schizophrenia patients with PNS exhibited widespread cortical-striatal functional connectivity abnormalities,particularly reduced rsFC between the putamen and the MFG,MCC and insula.
8.Alterations in striatal functional connectivity in schizophrenia patients with predominant negative symptoms
Yao ZHNAG ; Qin-yu LYU ; Xin-xin HUANG ; Chong-ze WANG ; Qi YAN ; Pei-juan WANG ; Zheng-hui YI
Fudan University Journal of Medical Sciences 2025;52(4):492-499
(rsFC)and their relationship with negative symptoms in schizophrenia patients with predominant negative symptoms(PNS).Methods Fifty-four schizophrenia patients with PNS and sixty-one healthy controls underwent resting-state functional magnetic resonance imaging(fMRI)scans.Data were collected on general demographic information,the Positive and Negative Syndrome Scale(PANSS),the Scale for the Assessment of Negative Symptoms(SANS),and the Temporal Experience of Pleasure Scale(TEPS).Twelve striatal subregions were selected as regions of interest(ROIs)to analyze the rsFC between each ROI and whole-brain voxels.The rsFC values of areas with significant differences were extracted for Pearson correlation analysis with negative symptoms.Results Compared with healthy controls,schizophrenia patients with PNS exhibited decreased rsFC between the right dorsal caudal putamen(DCP)and right insula,left middle frontal gyrus(MFG),right median cingulate and paracingulate gyri(MCC);between the left DCP and right putamen,left insula,left MFG;between the right dorsal rostral putamen(DRP)and bilateral MFG,left insula,right MCC;between the left DRP and right insula,left rolandic operculum;between the right ventral rostral putamen(VRP)and bilateral putamen,left MFG,right MCC;between the left VRP and right insula,left putamen,bilateral MFG,right MCC,left inferior parietal gyrus,excluding supramarginal and angular gyri.Decreased rsFC was also observed between the left ventral caudate/nucleus accumbens(inferior)and right insula,left anterior cingulate cortex,supracallosal,bilateral precuneus(a threshold of P<0.001 in voxel-level with P<0.05 in cluster-lever,corrected for family-wise error,PFWE<0.05/12=0.004).No regions showed increased rsFC in schizophrenia patients with PNS relative to healthy controls.And no significant correlations were found between striatal rsFC and negative symptoms(PBonferroni>0.05).Conclusion Schizophrenia patients with PNS exhibited widespread cortical-striatal functional connectivity abnormalities,particularly reduced rsFC between the putamen and the MFG,MCC and insula.
9.Antimicrobial resistance and related risk factors of carbapenem-resistant Klebsiella pneumoniae isolated from blood
Pei-Juan TANG ; Peng-Wen OUYANG ; Sheng LONG ; Na PENG ; Zi-Han WANG ; Qiong LIU ; Wen XU ; Liang-Yi XIE
Chinese Journal of Infection Control 2024;23(1):49-57
Objective To explore the antimicrobial resistance of carbapenem-resistant Klebsiella pneumoniae(CRKP)isolated from blood and the related risk factors for infection in patients.Methods Clinical data of 383 KP-infected patients from whose blood Klebsiella pneumoniae(KP)were isolated during hospitalization period in a hos-pital from January 2018 to December 2021 were retrospectively analyzed.Patients were divided into CRKP group(n=114)and non-CRKP group(n=269)based on antimicrobial resistance.According to the prognosis,114 patients in the CRKP group were subdivided into the death group(n=30)and the survival group(n=84).General informa-tion,underlying diseases,antimicrobial use,and infection outcomes of two groups of patients were compared,and risk factors for infection and death after infection were analyzed.Results The resistance rates of KP to tigecycline and compound sulfamethoxazole showed upward trends,with statistically significant differences(both P=0.008).The CRKP group had higher resistance rates to amikacin,aztreonam,compound sulfamethoxazole,ciprofloxacin,cefepime,cefoperazone/sulbactam,piperacillin/tazobactam,tigecycline,ceftazidime,tobramycin,and levofloxacin,as well as higher in-hospital mortality than the non-CRKP group,with statistically significant differences(all P<0.05).Acute pancreatitis prior to infection(OR=16.564,P<0.001),hypoalbuminemia(OR=8.588,P<0.001),stay in in-tensive care unit prior to infection(OR=2.733,P=0.017),blood transfusion(OR=3.968,P=0.001),broncho-scopy(OR=5.194,P=0.014),surgery within 30 days prior to infection(OR=2.603,P=0.010),and treatment with carbapenems(OR=2.663,P=0.011)were independent risk factors for the development of CRKP blood-stream infection(BSI).Cardiac insufficiency before infection(OR=11.094,P=0.001),combined with pulmonary infection(OR=20.801,P=0.010),septic shock(OR=9.783,P=0.002),disturbance of consciousness(OR=11.648,P=0.001),and receiving glucocorticoid treatment(OR=5.333,P=0.018)were independent risk factors for mortality in patients with CRKP BSI.Conclusion The resistance rate of KP from BSI to tigecycline and com-pound sulfamethoxazole presents upward trend.Underlying diseases,invasive procedures,and carbapenem treat-ment are closely related to CRKP BSI.Cardiac insufficiency,pulmonary infection,septic shock,disturbance of con-sciousness,and glucocorticoid treatment can lead to death of patients with CRKP BSI.
10.Exploring Scientific Connotation of "Fried Charcoal Survivability" of Lonicerae Japonicae Flos Based on Color-composition Correlation
Ting ZOU ; Jing WANG ; Xu WU ; Kai YANG ; Ming DANG ; Xiuchu GUO ; Lin WANG ; Chenxi LUO ; Juan PEI ; Chongbo ZHAO
Chinese Journal of Experimental Traditional Medical Formulae 2024;30(4):175-182
ObjectiveTo explore the scientific connotation of fried charcoal survivability of Lonicerae Japonicae Flos(LJF) by analyzing the correlation between the color change and the intrinsic components during the processing of LJF Carbonisata(LJFC), and taking pH, charcoal adsorption and microscopic characteristics as indexes. MethodLJFC samples with different degrees of processing were prepared according to the stir-frying time of 0.0, 1.5, 3.0, 4.5, 6.0, 7.5, 9.0, 10.5 min(numbered S1-S8), and the contents of gallic acid, chlorogenic acid, cryptochlorogenic acid, rutin, luteoloside, isochlorogenic acid A and isochlorogenic acid C were determined by high performance liquid chromatography(HPLC), and the L*(brightness), a*(red-greenness) and b*(yellow-blueness) of LJFC samples with different degrees of processing were determined by spectrophotometer, and the correlation analysis and principal component analysis(PCA) between the contents of seven representative components and the color of the samples were carried out by SPSS 26. 0 and SIMCA-P 14.1. Then pH, adsorption force and characteristic structure of different samples of LJFC were detected and the processing pattern of LJFC was analyzed. ResultThe results of quantitative analysis revealed that the contents of luteoloside, rutin, chlorogenic acid and isochlorogenic acid A gradually decreased, and the contents of cryptochlorogenic acid, isochlorogenic acid C and gallic acid firstly increased and then decreased. The L* and b* of the sample powders decreased, and a* showed a trend of increasing and then decreasing. The L* and b* were positively correlated with the contents of chlorogenic acid, rutin, luteoloside, isochlorogenic acid A, b* was positively correlated with the content of gallic acid, and a* was positively correlated with the contents of cryptochlorogenic acid and isochlorogenic acid C. PCA revealed that samples could be clearly divided into 3 groups, S1-S2 as one group, S3-S5 as one group, and S6-S8 as one group, with S3 having the highest score. The results of regression analysis showed that only isochlorogenic acid C could be used to predict the contents of components by colorimetric values combined with regression equations. Physicochemical analysis showed that pH of LJFC increased with the increase of degree of charcoal stir-frying, while adsorption force showed a tendency of increasing and then decreasing, with the highest adsorption force in the S5 sample, and the non-glandular hairs, calcium oxalate clusters and pollen grains had a varying degree of decreasing with the deepening of processing degree, and the microstructures of S6-S8 samples were obviously charred with pollen grains almost invisible. ConclusionThe changes in chemical composition and color characteristics of LJFC during the processing have certain correlations, combined with the changes in physicochemical properties, S5 sample is found to be the optimal processed products, which can provide a reference for the processing standardization and quality evaluation of LJFC, and enrich the scientific connotation of fried charcoal survivability of LJF.

Result Analysis
Print
Save
E-mail