| 1. |
- Barimah, Alberta Osei, et al.
(författare)
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Sensitive label-free Cu2O/Ag fused chemometrics SERS sensor for rapid detection of total arsenic in tea
- 2021
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Ingår i: Food Control. - : Elsevier. - 0956-7135 .- 1873-7129. ; 130
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Tidskriftsartikel (refereegranskat)abstract
- Arsenic (As) is one of the toxic, persistent, and lethal heavy metalloids and requires rapid, less costly, and sensitive detection methods. This study proposed a label-free cuprous oxide/silver (Cu2O/Ag) surface-enhanced Raman scattering (SERS) nanoprobe to detect total As in tea. Different total As spiked tea concentrations were mixed with the Cu2O/Ag SERS nanoprobe for the SERS detection. Quantitative models were established for predicting the total As in tea by comparatively applying chemometric algorithms. Amongst the algorithms, competitive adaptive reweighted sampling partial least squares (CARS-PLS) optimized the most effective spectral variables to predict the total As in tea efficiently. The CARS-PLS gave the highest correlation coefficient value (R-p = 0.9935), very low root means square error (RMSEP = 0.0496 mu g g(-1)) in the prediction set and recorded the highest RPD value of 8.819. The proposed nanoprobe achieved a lower detection limit (0.00561 mu g g(-1)), excellent selectivity, satisfactory reproducibility, and stability. No significant difference was recorded when the performance of the Cu2O/Ag total As SERS sensor was compared with the inductively coupled plasma mass spectrometry (ICP-MS) method. Therefore, this developed Cu2O/Ag coupled chemometrics SERS sensing method could be used to efficiently determine, quantify, and predict total As in tea to promote monitoring of heavy metal contaminants.
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| 2. |
- Guo, Zhiming, et al.
(författare)
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Chemometrics coupled 4-Aminothiophenol labelled Ag-Au alloy SERS off-signal nanosensor for quantitative detection of mercury in black tea
- 2020
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Ingår i: Spectrochimica Acta Part A - Molecular and Biomolecular Spectroscopy. - : Elsevier BV. - 1386-1425 .- 1873-3557. ; 242
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Tidskriftsartikel (refereegranskat)abstract
- Black tea like other food crops is prone to mercury ion (Hg2+) contamination right from cultivation to industrial processing. Due to the dangerous health effects posed even in trace contents, sensitive detection and quantification sensors are required. This study employed the surface-enhanced Raman scattering (SERS) enhancement property of 4-aminothiophenol (4-ATP) as a signal turn off approach functionalized on Ag-Au alloyed nanopartide to firstly detect Hg2+ in standard solutions and spiked tea samples. Different chemometric algorithms were applied on the acquired SERS and inductively coupled plasma-mass spectrometry (ICP-MS) chemical reference data to select effective wavelengths and spectral variables in order to develop models to predict the Hg2+. Results indicated that Ag-Au/4-ATP SERS sensor combined with ant colony optimization partial least squares (ACO-PLS) exhibited the best correlation efficient and minimum errors for Hg2+ standard solutions (R-c = 0.984, R-p = 0.974, RMSEC = 0.157 mu g/mL, RMSEP = 0.211 mu g/mL) and spiked tea samples (R-c = 0.979, R-p = 0.963, RMSEC = 0.181 mu g/g and RMSEP = 0210 mu g/g). The limit of detection of the proposed sensor was 4.12 x 10(-7) mu g/mL for Hg2+ standard solutions and 2.83 x 10(-5) mu g/g for Hg2+ spiked tea samples. High stability and reproducibility with relative standard deviation of 1.14% and 0.84% were detected. The potent strong relationship between the SERS sensor and the chemical reference method encourages the application of the developed chemometrics coupled SERS system for future monitoring and evaluation of Hg2+ in tea.
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| 3. |
- Guo, Zhiming, et al.
(författare)
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Classification for Penicillium expansum Spoilage and Defect in Apples by Electronic Nose Combined with Chemometrics
- 2020
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Ingår i: Sensors. - : MDPI AG. - 1424-8220. ; 20:7
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Tidskriftsartikel (refereegranskat)abstract
- It is crucial for the efficacy of the apple storage to apply methods like electronic nose systems for detection and prediction of spoilage or infection by Penicillium expansum. Based on the acquisition of electronic nose signals, selected sensitive feature sensors of spoilage apple and all sensors were analyzed and compared by the recognition effect. Principal component analysis (PCA), principle component analysis-discriminant analysis (PCA-DA), linear discriminant analysis (LDA), partial least squares discriminate analysis (PLS-DA) and K-nearest neighbor (KNN) were used to establish the classification model of apple with different degrees of corruption. PCA-DA has the best prediction, the accuracy of training set and prediction set was 100% and 97.22%, respectively. synergy interval (SI), genetic algorithm (GA) and competitive adaptive reweighted sampling (CARS) are three selection methods used to accurately and quickly extract appropriate feature variables, while constructing a PLS model to predict plaque area. Among them, the PLS model with unique variables was optimized by CARS method, and the best prediction result of the area of the rotten apple was obtained. The best results are as follows: Rc = 0.953, root mean square error of calibration (RMSEC) = 1.28, Rp = 0.972, root mean square error of prediction (RMSEP) = 1.01. The results demonstrated that the electronic nose has a potential application in the classification of rotten apples and the quantitative detection of spoilage area.
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| 4. |
- Guo, Zhiming, et al.
(författare)
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Identification of the apple spoilage causative fungi and prediction of the spoilage degree using electronic nose
- 2021
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Ingår i: Journal of food process engineering. - : John Wiley & Sons. - 0145-8876 .- 1745-4530. ; 44:10
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Tidskriftsartikel (refereegranskat)abstract
- Apple is resistant to storage, but it is susceptible to fungal infection during transportation and storage, resulting in serious losses after harvest. A convenient and nondestructive monitoring method for fungi-inoculated apples was proposed in this research. Four dominant spoilage fungi, including Aspergillus niger, Penicillium expansum, Penicillium chrysogenum, and Alternaria alternata, were inoculated on apple samples. The volatile information of samples with different degrees of spoilage was obtained by gas sensors. The pattern recognition methods were compared to classify the fungi and degrees of spoilage. Back propagation-artificial neural networks (BP-ANN) had the best identification model result with the highest recognition rates of 95.62 and 99.58% for fungi and spoilage degrees, respectively. The variable selection methods were employed, and variables of the gas sensors data for the prediction of apple spoilage area were optimized. The best prediction models of Aspergillus niger, Penicillium expansum, Penicillium chrysogenum, and Alternaria alternata were 0.854, 0.939, 0.909, and 0.918, respectively. The results show that the gas sensors can be used as a nondestructive technique in apple fungi infection evaluation. This proposed fruit spoilage detection technology is expected to provide a reference for the early detection of apple spoilage to promote food quality and safety inspection.Practical ApplicationsThis research used gas sensors to identify the four main spoilage fungi of apples and predicted the spoilage degree of apples using established prediction models. The apple spoilage detection method adopted in this research provides a reference for the early detection of fruit spoilage, which is helpful for apple storage and reduces the economic loss caused by corruption. It is an important measure to help ensure the economic benefits of apple and provide consumers with a large number of high-quality apple products.
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| 5. |
- Khalifa, Shaden A. M., et al.
(författare)
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Cyanobacteria-From the Oceans to the Potential Biotechnological and Biomedical Applications
- 2021
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Ingår i: Marine Drugs. - : MDPI AG. - 1660-3397. ; 19:5
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Forskningsöversikt (refereegranskat)abstract
- Cyanobacteria are photosynthetic prokaryotic organisms which represent a significant source of novel, bioactive, secondary metabolites, and they are also considered an abundant source of bioactive compounds/drugs, such as dolastatin, cryptophycin 1, curacin toyocamycin, phytoalexin, cyanovirin-N and phycocyanin. Some of these compounds have displayed promising results in successful Phase I, II, III and IV clinical trials. Additionally, the cyanobacterial compounds applied to medical research have demonstrated an exciting future with great potential to be developed into new medicines. Most of these compounds have exhibited strong pharmacological activities, including neurotoxicity, cytotoxicity and antiviral activity against HCMV, HSV-1, HHV-6 and HIV-1, so these metabolites could be promising candidates for COVID-19 treatment. Therefore, the effective large-scale production of natural marine products through synthesis is important for resolving the existing issues associated with chemical isolation, including small yields, and may be necessary to better investigate their biological activities. Herein, we highlight the total synthesized and stereochemical determinations of the cyanobacterial bioactive compounds. Furthermore, this review primarily focuses on the biotechnological applications of cyanobacteria, including applications as cosmetics, food supplements, and the nanobiotechnological applications of cyanobacterial bioactive compounds in potential medicinal applications for various human diseases are discussed.
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| 6. |
- Algethami, Jari S., et al.
(författare)
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Bee Pollen : Clinical Trials and Patent Applications
- 2022
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Ingår i: Nutrients. - : MDPI AG. - 2072-6643. ; 14:14
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Forskningsöversikt (refereegranskat)abstract
- Bee pollen is a natural cocktail of floral nectar, flower pollen, enzymes, and salivary secretions produced by honeybees. Bee pollen is one of the bee products most enriched in proteins, polysaccharides, polyphenols, lipids, minerals, and vitamins. It has a significant health and medicinal impact and provides protection against many diseases, including diabetes, cancer, infectious, and cardiovascular. Bee pollen is commonly promoted as a cost-effective functional food. In particular, bee pollen has been applied in clinical trials for allergies and prostate illnesses, with a few investigations on cancer and skin problems. However, it is involved in several patents and health recipes to combat chronic health problems. This review aimed to highlight the clinical trials and patents involving bee pollen for different cases and to present the role of bee pollen as a supplementary food and a potential product in cosmetic applications.
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| 7. |
- Barimah, Alberta Osei, et al.
(författare)
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SERS nanosensor of 3-aminobenzeneboronic acid labeled Ag for detecting total arsenic in black tea combined with chemometric algorithms
- 2022
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Ingår i: Journal of Food Composition and Analysis. - : Elsevier. - 0889-1575 .- 1096-0481. ; 110
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Tidskriftsartikel (refereegranskat)abstract
- Detrimental health effects caused by the intake of food contaminated with heavy metals have drawn concerns on effective monitoring using rapid and benign methods. This work presented a novel surface-enhanced Raman scattering (SERS)-based 3-Aminobenzeneboronic acid (ABBA) labeled silver (Ag) nanosensor combined with chemometric algorithms to detect and predict total arsenic (TAs) in acid digested spiked black tea leaves. The sensor recognizes TAs through the partial detachment of ABBA and the chemical formation of As-O-Ag linkage between the TAs and the Ag nanoparticles, which caused a SERS-on signal enhancement effect. SERS combined with competitive adaptive reweighted sampling partial least squares algorithm predicted the TAs with higher correlation coefficient (R-p) results (R-p = 0.9750) and a detection limit of 0.0273 mu g/g. Good recoveries of 83.84-109.53% and the excellent agreement with the inductively coupled plasma-mass spectrometry method (R-2 = 0.999) revealed this developed rapid method could be deployed for fast-tracking of As in food samples.
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| 8. |
- Cai, Jianrong, et al.
(författare)
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Characterization and recognition of citrus fruit spoilage fungi using Raman scattering spectroscopic imaging
- 2023
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Ingår i: Vibrational Spectroscopy. - : Elsevier. - 0924-2031 .- 1873-3697. ; 124
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Tidskriftsartikel (refereegranskat)abstract
- Citrus fruit is cultivated globally with a high production every year. However, it is easily infected by spoilage fungi with toxic metabolites. The mechanism of changes in peel tissues of mandarins was revealed by Raman microscopic imaging. Single Raman spectra, multiple Raman spectra and microscopic images of fresh fruits and infected fruits by spoilage fungi were acquired by confocal Raman microscopy. Intensity reduction of Raman characteristic peaks at 1008 cm(-1),1154 cm(-1) and 1525 cm(-1) indicated the content of carotenoids in citrus fruit peels decreased significantly during the periods of fruit spoilage. The distribution and composition of carotenoids in the mandarins were directly illustrated on the visualized microscopic images. Classification algorithms were operated in discrimination on fresh and spoilage samples based on Raman spectra. Classification on fresh fruits and all spoiled fruits were better than that of identification on four levels (fresh samples, slight spoilage samples, medium spoilage samples and serious spoilage samples). Liner discriminant analysis (LDA) of mandarins infected by A. alternate achieved the optimal result, with correlation coefficients of calibration set and prediction set both reaching 100%. The correlation coefficients of samples infected by A. niger achieved 0.925 for calibration set and 0.900 for prediction set. Meanwhile, infected samples by P. italicum reached 0.842 and 0.800. Raman microscopic imaging was confirmed to be a powerful tool to identify compositional changes in fruits caused by spoilage fungi without chemical treatments.
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| 9. |
- Chen, Ping, et al.
(författare)
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Green reduction of silver nanoparticles for cadmium detection in food using surface-enhanced Raman spectroscopy coupled multivariate calibration
- 2022
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Ingår i: Food Chemistry. - : Elsevier. - 0308-8146 .- 1873-7072. ; 394
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Tidskriftsartikel (refereegranskat)abstract
- Cadmium (Cd) causes pervasive harm on human health as a poisonous heavy metal. This study proposed a surface-enhanced Raman spectroscopy (SERS) approach using sodium alginate (SA) as green reductant in combination with edge enrichment and chemometrics to build label-free Cd quantitative models. The silver nanoparticles synthesized by SA had good dispersion and enhancement factor (3.48 x 105). The optimal detection system was established by optimizing the concentration of specific molecules (trimercaptotriazine) and the droplet volume of measured liquid. Partial least squares models based on preprocessing methods and selection algorithms were compared. The results indicated that the model combined with first-order derivative preprocessing and competitive adaptive reweighted sampling algorithms achieved the best performance (R-p = 0.9989, RMSEP =1.6225) with the limit of detection of 2.36 x 10(-5) mu g L-1 in food. The SERS approach combined with edge enrichment and chemometrics holds promise for rapid and label-free determination of Cd in food.
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| 10. |
- El-Garawani, Islam M., et al.
(författare)
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In Vitro Induction of Apoptosis in Isolated Acute Myeloid Leukemia Cells : The Role of Anastatica hierochuntica Methanolic Extract
- 2022
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Ingår i: Metabolites. - : MDPI AG. - 2218-1989 .- 2218-1989. ; 12:9
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Tidskriftsartikel (refereegranskat)abstract
- Anastatica hierochuntica L. (Cruciferae) has been known in Egyptian folk medicine as a remedy for gastrointestinal disorders, diabetes and heart diseases. Despite the wide usage, A. hierochuntica research provides insufficient data to support its traditional practice. The cytotoxicity of A. hierochuntica methanolic extract was investigated on acute myeloid leukemia blasts (AML) and normal human peripheral leucocytes (NHPL). The phytochemical identification of bioactive compounds using 1H-NMR and LC-ESI-MS was also performed. A. hierochuntica extract caused non-significant cytotoxicity on NHPL, while the cytotoxicity on AML was significant (IC50: 0.38 ± 0.02 μg/mL). The negative expression of p53, upregulation of Caspase-3 and increase in the BAX/BCL-2 ratio were reported at the protein and mRNA levels. The results suggest that A. hierochuntica extract induced AML cell death via the p53-independent mitochondrial intrinsic pathway and further attention should be paid to this plant as a promising natural anticancer agent.
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