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Exposure of antimalarial herbal drugs (AMHDs) to ultraviolet radiation (UVR) affects the potency and integrity of the AMHDs. Instant classification of the AMHDs exposed to UVR (UVR-AMHDs) from unexposed ones (Non-UVR-AMHDs) would be beneficial for public health safety, especially in warm regions. For the first time, this work combined laser-induced autofluorescence (LIAF) with chemometric techniques to classify UVR-AMHDs from Non-UVR-AMHDs. LIAF spectra data were recorded from 200 ml of each of the UVR-AMHDs and Non-UVR-AMHDs. To extract useful data from the spectra fingerprint, principal components (PCs) analysis was used. The performance of five chemometric algorithms: random forest (RF), neural network (NN), support vector machine (SVM), linear discriminant analysis (LDA), and k-nearest neighbour (KNN), were compared after optimization by validation. The chemometric algorithms showed that KNN, SVM, NN, and RF were superior with a classification accuracy of 100% for UVR-AMHDs while LDA had a classification accuracy of 98.8% after standardization of the spectra data and was used as an input variable for the model. Meanwhile, a classification accuracy of 100% was obtained for KNN, LDA, SVM, and NN when the raw spectra data was used as input except for RF for which a classification accuracy of 99.9% was obtained. Classification accuracy above 99.74 ± 0.26% at 3 PCs in both the training and testing sets were obtained from the chemometric models. The results showed that the LIAF, combined with the chemometric techniques, can be used to classify UVR-AMHDs from Non-UVR-AMHDs for consumer confidence in malaria-prone regions. The technique offers a non-destructive, rapid, and viable tool for identifying UVR-AMHDs in resource-poor countries. [ABSTRACT FROM AUTHOR] more...

Differential pulse voltammetry (DPV) and spectrophotometric methods were used to evaluate the antioxidant capacity (AC) in strawberry and orange juice, soluble coffee, rosemary extract, red wine, and sparkling white wine. The AC through spectrophotometric methods showed the following trend in solid foods, coffee > rosemary extract, and red wine > strawberry juice > orange juice > sparkling white wine in liquid samples. Charge measurements by DPV, presented in equivalent units of Trolox and gallic acid, showed the same trend in liquid samples; however, for solid samples, the AC of rosemary extract was greater than that of coffee. The charge expressed in equivalent units showed a high, positive, and significant correlation (p < 0.001) with total phenols (0.7919), FRAP (0.8875), and ABTS (0.8366). The proposed electrochemical technique proves to be a fast, reliable, and environmentally friendly alternative or complement to evaluate antioxidant capacity in food, which is not affected by the turbidity or color of the samples. [ABSTRACT FROM AUTHOR] more...

In the scope of a research program with the goal of developing treatments for inflammatory diseases, the pharmacological evaluation of LQFM291, designed by molecular hybridization from butylated hydroxytoluene and paracetamol, was described. The antioxidant profile of LQFM291 was evaluated by electrochemical measurement. Also, acute or repeated treatments with equimolar doses to paracetamol were used to evaluate the antinociceptive and/or anti-inflammatory activities of LQFM291 in animal models. The toxicologic potential of LQFM291 was also evaluated and compared to paracetamol through biochemical and histopathological analysis after the repeated treatment schedule. As a result of the acute treatment, paracetamol showed a similar antinociceptive effect in formalin test compared to LQFM291. Whereas, after the repeated treatment, when carrageenan-induced hyperalgesia and edema tests were performed, paracetamol showed a delayed antinociceptive and anti-inflammatory effect compared to LQFM291. Furthermore, as other advantages the LQFM291 showed a high redox capacity, a gastroprotective activity and a safety pharmacological profile without any liver or kidney damage. These effects can be related to the prevention of oxidative stress by reduction of protein and lipid peroxidation in gastric tissue, maintenance of glutathione levels in hepatic homogenate, and a systemic reduction of pro-inflammatory cytokine levels, which may characterize the LQFM291 as a more viable and effective alternative to relief pain and inflammatory signs in patients with chronic disorders. [ABSTRACT FROM AUTHOR] more...

Turmeric is widely used as a health supplement and foodstuff in South East Asian countries because of its medicinal benefits. Like several other plants and peppers, turmeric is prone to exploitation because of its economic value, rising consumer need, and essential food element that adds colour and flavour. Due to this, quick and comprehensive testing processes are needed to detect adulterants in turmeric. In this study, pure turmeric powders were mixed with starch in proportions ranging from 0 to 50% with a 1% variation to obtain different combinations. Reflectance spectra of pure turmeric and starch mixed samples were recorded using a JASCO-V770 spectrometer from 400 to 2050 nm. The recorded spectra were pre-processed using a Multiplicative Scatter Correction (MSC) and Standard Normal Variate (SNV). The Savitzky-Golay (SG) filter was initially applied to these original (X), MSC, and SNV-corrected spectra. Secondly, the Extra Tree Regressor (ETR) feature selection method was employed to select the best features. Finally, principal component analysis (PCA) was used to reduce the dimension of the selected features. The stacked generalization method was applied to improve the performance of this work. Both regressors and classifier stacking techniques have been tested with different classification and regression methods. The K-Nearest Neighbours (KNN), Decision Tree (DT), and Random Forest (RF) models were used as base learners, and Logistic Regression (LRC) was used as a meta-model for classification and Linear Regression (LR) for regression analysis. The proposed method achieved the best regression performance with r2 of 0.999, Root Mean Square Error (RMSE) of 0.206, Ratio of Performance to Deviation (RPD) of 73.73, and Range Error Ratio (RER) of 480.58, whereas 100% F1 score and Matthew's Correlation Coefficient (MCC) classification performance. [ABSTRACT FROM AUTHOR] more...

Background: The production of red fruits, such as blueberry, has been threatened by several stressors from severe periods of drought, nutrient scarcity, phytopathogens, and costs with fertilization programs with adverse consequences. Thus, there is an urgent need to increase this crop's resilience whilst promoting sustainable agriculture. Plant growth-promoting microorganisms (PGPMs) constitute not only a solution to tackle water and nutrient deficits in soils, but also as a control against phytopathogens and as green compounds for agricultural practices. Methods: In this study, a metagenomic approach of the local fungal and bacterial community of the rhizosphere of Vaccinium corymbosum plants was performed. At the same time, both epiphytic and endophytic microorganisms were isolated in order to disclose putative beneficial native organisms. Results: Results showed a high relative abundance of Archaeorhizomyces and Serendipita genera in the ITS sequencing, and Bradyrhizobium genus in the 16S sequencing. Diversity analysis disclosed that the fungal community presented a higher inter-sample variability than the bacterial community, and beta-diversity analysis further corroborated this result. Trichoderma spp., Bacillus spp., and Mucor moelleri were isolated from the V. corymbosum plants. Discussion: This work revealed a native microbial community capable of establishing mycorrhizal relationships, and with beneficial physiological traits for blueberry production. It was also possible to isolate several naturally-occurring microorganisms that are known to have plant growth-promoting activity and confer tolerance to hydric stress, a serious climate change threat. Future studies should be performed with these isolates to disclose their efficiency in conferring the needed resilience for this and several crops. [ABSTRACT FROM AUTHOR] more...

Petroleum products are the target of fraudulent practices due to their high commercial value. The aim of this study is to provide a new analysis system to assess motor oil adulteration. For this purpose, Laser Induced Fluorescence (LIF) spectroscopy was exploited coupled with chemometric tools to detect motor oil adulteration by three types of cheap motor oils. Principal Component Analysis (PCA) was able to distinguish samples in three groups according to the type of adulterant. Besides, Partial Least Squares Regression (PLSR) was exploited to determine the percentage of adulteration. The best model was obtained with a regression coefficient of 0.96, Root Mean Square Error of Prediction (RMSEP) of 2.83, Standard Error of Prediction (SEP) of 2.83 and Bias of 0.40. The main results of this work provide new analysis system using the combination of LIF spectroscopy combined to PCA and PLS as an efficient and fast method for motor oil analysis. [ABSTRACT FROM AUTHOR] more...

In this work, the development of a disposable electrochemical device (US$ 0.02 per electrode) using a 3D printed support (3Ds) of acrylonitrile butadiene styrene (ABS) insulating filament with a composite material (CM) based on graphite and nail polish, immobilized on the support surface, was described for the electrochemical determination of diclofenac (DCF). The device was compared to the commercial glassy carbon electrode (GCE) and showed superior electroanalytical performance with approximately 1.8-fold higher current density. Additionally, an amperometric method for DCF determination in tap water, synthetic urine, and pharmaceutical formulation samples with the proposed electrode, using a flow injection analysis (FIA-AD) system, was developed. The optimized method presented excellent detectability (LOD = 0.47 µmol L−1), with excellent precision and accuracy (relative standard deviation < 5.6%) and percent recovery from spiked samples ranging from 89 to 106%. In addition, the sensor showed optimal analytical frequency with approximately 108 injections per hour, which demonstrates the potential of this system using the proposed disposable electrode for implementation in routine analysis and quality control with good selectivity and sensitivity. [ABSTRACT FROM AUTHOR] more...

The physicochemical property of water-insoluble drug piroxicam (PY) in the presence of two. ionic-mixed micellar systems was investigated. The two systems were pluronic L-81-sodium dodecyl sulfate (SDS), a nonionic-anionic; and pluronic L-81-cetyl pyridinium bromide (CPB), a nonionic-cationic. The characterizations employed were UV–visible spectroscopy, FTIR spectroscopy, conductivity, cloud point and cyclic voltammetry measurements. The results from UV spectra showed that there was different behaviour of piroxicam with anionic and cationic mixed micelles. But, the common observation for both sets was that the drug absorption with a mixed micellar system displayed an intermediate position compared to both the single micellar systems. There was short and strong bond formation in the complex formed between piroxicam and mixed micelles as evidenced by FTIR studies. The conductivity measurements revealed that the drug and mixed micelle in the produced complex have a stable and spontaneous binding. The free energy of micellization ∆Gm was observed to be -18.04 kJ/mole for piroxicam [PY + L-81] + SDSa group and -37.73 kJ/mole for piroxicam [PY + L-81] + CPBc group. The higher negative value of the nonionic-cationic system indicates greater stability of the drug in the system. The cloud point measurements corroborated this finding. The cyclic voltammetry study of piroxicam with ionic surfactant SDS/CPB displays greater electrostatic interaction in mixed micelle combination (PY/CPB/L-81) compared to single micelle combination (PY/CPB) and pure drug. The combination is novel for the hydrophobic drug piroxicam which can be used by the formulation scientist. Interaction of drug (PY) and surfactant (SDS/CPB) presence of pluronic L-81 [ABSTRACT FROM AUTHOR] more...

The versatility of immobilized enzyme systems enables rapid recovery of both product and enzyme, numerous re-uses of enzymes, continuous enzymatic processes, quick reaction termination, and a wider range of bioreactor designs. Immobilized enzymes have been the topic of significant research because of their remarkable functional characteristics such as optimal nature, reusability, and cost-effectiveness. In addition to industrial operations, enzyme immobilization technology is also utilized as component technology in the food industry, biomaterial detection, medical diagnostics, bioenergy, and therapeutics. To demonstrate its important uses, several sorts of biosensors, such as enzyme-based biosensors, enzyme-based thermistors, electrochemical biosensors, optical biosensors, DNA biosensors, immunosensors, magnetic biosensors, and thermal biosensors have been debated here. A flexible and highly functioning enzyme is utilized for analyte identification by oxidizing enzymes such as peroxidases and polyphenol oxidize such as laccases and tyrosinases. These enzymes are therefore regarded as appealing and intriguing compounds for biosensors. New systems of reliable biosensor interfaces have gathered considerable interest in recent years. This study highlights key prospects, the newest technologies and materials utilized to build robust biosensor interfaces. These materials include polymers, nanomaterials and their composites i.e. nanocomposites were used for the designation of biosensors. This review studies recent advances in stability interface solutions for biosensors, which may give researchers some references and novel approaches to further investigate new materials and methodologies in biomedical applications. [ABSTRACT FROM AUTHOR] more...

Purpose: The development biosensing technologies capable of delivering fast and reliable analysis is a growing trend in drug quality control. Considering the emerging use of plant-based polyphenol oxidases (PPO) as biological component of electrochemical biosensors, this work reports the first Solanum lycocarpum PPO biosensor and its use in the pharmaceutical analysis of paracetamol in tablet formulations. Methods: The biosensor was optimized regarding fruit maturation (immature and mature-ripe), vegetal extract volume to be used in biosensor construction as well as optimal pH of electrochemical cell fluid. Results: Results evidenced that the extract which rendered the biosensor with best analytical performance was from immature fruits, and the biosensor produced using 100 µL of crude plant extract promoted better faradaic signal gathering. Moreover, when neutral pH media was used in the electrochemical cell, the biosensor showcased best faradaic signal output from the used redox probe (catechol), suggesting thence that the method presents high sensibility for phenolic compounds detection. Furthermore, the biosensor was able to quantify paracetamol in a linear range from 50 to 300 µM, showcasing LoD and LoQ of 3 µM and 10 µM, respectively. Conclusion: after careful evaluation, this biosensor might be a low-cost alternative for conventional pharmaceutical quality control methods. [ABSTRACT FROM AUTHOR] more...

In this paper, a kind of soybean nodule-derived nitrogen-doped carbon (SNNDC) was prepared, characterized and applied to modify the assembled carbon paste electrode (CPE), to fabricate a novel chemical sensor for the detections of AA and DA. The electrochemical characteristics of SNNDC implied that it is an effective electron transfer mediator accelerating the electron transfer to CPE. The cyclic voltammetry measurements at different scan rates indicated that the electrochemical process on the electrode surface of the chemical sensor is a diffusion-controlled irreversible oxidation reaction of one-electron and one-proton for DA, and two-electron with one-proton for AA. The linear detection ranges of the chemical sensor for the detections of AA and DA were 5–3000 μM and 5–1000 μM with the detection limits of 1.90 μM and 3.18 μM, respectively, as determined by amperometric experiments. Both linear detection range and detection limit obtained are comparable or better than those of several modified electrodes reported recently. And the chemical sensor was also successfully applied to the detections of AA and DA in injection samples. This study suggested that the fabricated chemical sensor is a hopeful candidate to be used in the detection of pharmaceutical samples of AA and DA, and provides valuable reference information for the development of novel drug sensors in both clinical laboratory and food industries. [ABSTRACT FROM AUTHOR] more...

This work reports a "green" method where silver nanoparticles (AgNPs) were synthesized using silver nitrate and the aqueous extract of black currant pomaces (BCPE). LC–MS spectrum showed the presence of 16 compounds with chlorogenic acid and caffeic acid as the dominant components of BCPE. Total phenolic content and total flavonoid content of extracts were determined. Various experimental techniques including iron (III) reducing capacity, total antioxidant capacity, and DPPH radical scavenging activity were used to characterize antioxidant activity of the extract. Scanning electron microscopy (SEM) and EDX analysis showed that silver nanoparticles were pure and polydisperse. The synthesized nanoparticles might serve as a potent antioxidant as revealed by DPPH assay. The synthesized nanoparticles (BCPE–AgNPs) efficiently inhibit pathogenic organisms such as Gram-negative bacteria. [ABSTRACT FROM AUTHOR] more...

This paper reports the preparation and electrochemical properties of the PbSO4 negative electrode with polyvinyl alcohol (PVA) and sodium polystyrene sulfonate (PSS) as the binders. The results show that the mixture of PVA and PSS added to the PbSO4 electrode can significantly improve the specific discharge capacity of the PbSO4 electrode, which reaches 110 mAh g−1 and survives 700 cycles at full charge and discharge at 100 mA g−1. The mixture of PVA and PSS can also replace the short fibers used in conventional cells, and shortens the activation time of the electrode. [ABSTRACT FROM AUTHOR] more...