Potential for Fourier transform infrared (FTIR) spectroscopy toward predicting antioxidant and phenolic contents in powdered plant matrices

Chrysin-functionalized gold nanoparticles and paclitaxel exhibit synergistic impact on lung cancer cell lines via regulating the AKT/PPAR-ϒ/β-catenin pathway

Lung cancer has become progressively widespread, posing a challenge to traditional chemotherapeutic drugs such as platinum compounds and paclitaxel (PTX) owing to growing resistance. Along with that, the chemotherapeutic drugs infer major side effects. The usage of natural compounds as chemosensitizers to boost the efficacy of these chemotherapeutic drugs and minimizing their toxicity is a plausible approach. In our investigation, we employed PTX as the standard chemotherapeutic agent and utilized chrysin-functionalized gold nanoparticles (CHR-AuNPs) to augment its cytotoxicity. Gold nanoparticles were chosen for their inherent cytotoxic properties and ability to enhance chrysin's bioavailability and solubility. Characterization of CHR-AuNP revealed spherical nanoparticles within the nano-size range (35-70 nm) with a stable negative zeta potential of -22 mV, confirmed by physicochemical analyses including UV-visible spectroscopy, Fourier transform infrared (FTIR) spectral analysis, and visual observation of the wine-red coloration. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay cytotoxicity studies demonstrated CHR-AuNP's superior efficacy compared to CHR alone, with synergistic effects observed in combination with PTX, validated by Compusyn software. Morphological changes indicative of apoptosis were more pronounced with combined treatment, corroborated by acridine orange/ethidium bromide (AO/EtBr) staining and Annexin V assays. Furthermore, the combination treatment amplified reactive oxygen species (ROS) production and destabilized mitochondrial membrane potential, while altering the expression of pro-apoptotic and anti-apoptotic proteins. Exploring the mechanistic pathways, we found that the drugs upregulated PPAR-γ expression while suppressing Akt and overexpressing PTEN, thereby impeding the Wnt/β-catenin pathway commonly dysregulated in lung cancer. This highlights the potential of low-dose combination therapy with PTX and CHR-AuNP as a promising strategy for addressing lung cancer's challenges.

Phytochemical Profiling, Antioxidant and Antimicrobial Potentials of Ethanol and Ethyl Acetate Extracts of Chamaenerion latifolium L

The study investigates the phytochemical profile, antioxidant capacity, and antimicrobial activities of ethanol (ChL-EtOH) and ethyl acetate (ChL-EtOAc) extracts from Chamaenerion latifolium L. (ChL) harvested in Kazakhstan. The ChL-EtOH extract exhibited higher total phenolic (267.48 ± 3.44 mg GAE/g DE) and flavonoid content (24.18 ± 1.06 mg QE/g DE) compared to ChL-EtOAc. HPLC-UV-ESI/MS identified key phenolic acids and flavonoids, including gallic acid, chlorogenic acid, and quercetin 3-glucoside. FT-IR analysis confirmed the presence of characteristic functional groups. Antioxidant assays revealed strong DPPH scavenging and FRAP activities, with ChL-EtOH showing superior results (IC50 = 21.31 ± 0.65 μg/mL and 18.13 ± 0.15 μg/mL, respectively). Additionally, ChL-EtOH displayed notable antimicrobial efficacy against Gram-positive and Gram-negative bacteria, as well as the fungal strain Candida albicans. These findings suggest that ethanol extraction is more efficient for isolating bioactive compounds from ChL, underscoring its potential for pharmaceutical and nutraceutical applications.

First ATR-FTIR Characterization of Black, Green and White Teas (Camellia sinensis) from European Tea Gardens: A PCA Analysis to Differentiate Leaves from the In-Cup Infusion

ATR-FTIR (Attenuated Total Reflectance Fourier Transform InfraRed) spectroscopy, combined with chemometric, represents a rapid and reliable approach to obtain information about the macromolecular composition of food and plant materials. With a single measurement, the chemical fingerprint of the analyzed sample is rapidly obtained. Hence, this technique was used for investigating 13 differently processed tea leaves (green, black and white) all grown and processed in European tea gardens, and their vacuum-dried tea brews, prepared using both hot and cold water, to observe how the components differ from tea leaf to the in-cup infusion. Spectra were collected in the 1800-600 cm-1 region and were submitted to Principal Component Analysis (PCA). The comparison of the spectral profiles of leaves and hot and cold infusions of tea from the same country, emphasizes how they differ in relation to the different spectral regions. Differences were also noted among the different countries. Furthermore, the changes observed (e.g., at ~1340 cm-1) due to catechin content, confirm the antioxidant properties of these teas. Overall, this experimental approach could be relevant for rapid analysis of various tea types and could pave the way for the industrial discrimination of teas and of their health properties without the need of time-consuming, lab chemical assays.

A pilot study on non-invasive in situ detection of phytochemicals and plant endogenous status using fiber optic infrared spectroscopy

Traditional methods for assessing plant health often lack the necessary attributes for continuous and non-destructive monitoring. In this pilot study, we present a novel technique utilizing a customized fiber optic probe based on attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) with a contact force control unit for non-invasive and continuous plant health monitoring. We also developed a normalized difference mid-infrared reflectance index through statistical analysis of spectral features, enabling differentiation of drought and age conditions in plants. Our research aims to characterize phytochemicals and plant endogenous status optically, addressing the need for improved analytical measurement methods for in situ plant health assessment. The probe configuration was optimized with a triple-loop tip and a 3 N contact force, allowing sensitive measurements while minimizing leaf damage. By combining polycrystalline and chalcogenide fiber probes, a comprehensive wavenumber range analysis (4000-900 cm-1) was achieved. Results revealed significant variations in phytochemical composition among plant species, for example, red spinach with the highest polyphenolic content and green kale with the highest lignin content. Petioles displayed higher lignin and cellulose absorbance values compared to veins. The technique effectively monitored drought stress on potted green bok choy plants in situ, facilitating the quantification of changes in water content, antioxidant activity, lignin, and cellulose levels. This research represents the first demonstration of the potential of fiber optic ATR-FTIR probes for non-invasive and rapid plant health measurements, providing insights into plant health and advancements in quantitative monitoring for indoor farming practices, bioanalytical chemistry, and environmental sciences.

The Use of Infrared Spectroscopy for the Quantification of Bioactive Compounds in Food: A Review

Infrared spectroscopy (wavelengths ranging from 750-25,000 nm) offers a rapid means of assessing the chemical composition of a wide range of sample types, both for qualitative and quantitative analyses. Its use in the food industry has increased significantly over the past five decades and it is now an accepted analytical technique for the routine analysis of certain analytes. Furthermore, it is commonly used for routine screening and quality control purposes in numerous industry settings, albeit not typically for the analysis of bioactive compounds. Using the Scopus database, a systematic search of literature of the five years between 2016 and 2020 identified 45 studies using near-infrared and 17 studies using mid-infrared spectroscopy for the quantification of bioactive compounds in food products. The most common bioactive compounds assessed were polyphenols, anthocyanins, carotenoids and ascorbic acid. Numerous factors affect the accuracy of the developed model, including the analyte class and concentration, matrix type, instrument geometry, wavelength selection and spectral processing/pre-processing methods. Additionally, only a few studies were validated on independently sourced samples. Nevertheless, the results demonstrate some promise of infrared spectroscopy for the rapid estimation of a wide range of bioactive compounds in food matrices.

Polyphenols in Jabuticaba (Plinia spp.) Peel Flours: Extraction and Comparative Evaluation of FTIR and HPLC for Quantification of Individual Compounds

Jabuticabas are wild fruits native to Brazil, and their peels, the main residue from jabuticaba processing, contain significant amounts of bioactive compounds, which are mostly phenolics. Conventional methods based on the estimation of total extractable phenolics (TEP—Folin–Ciocalteau) or total monomeric anthocyanins (TMA) have limitations and may not reflect the actual antioxidant potential of these peels. Analytical methods, such as high-performance liquid chromatography (HPLC), are more appropriate for the quantification of specific phenolics, and can be used as a reference for the construction of mathematical models in order to predict the amount of compounds using simple spectroscopic analysis, such as Fourier Transform Infrared Spectroscopy (FTIR). Therefore, the objectives of this study were (i) to evaluate the composition of specific polyphenols in flours prepared from jabuticaba peels and verify their correlation with TEP and TMA results from a previous study, and (ii) to employ FTIR coupled with chemometrics to predict the concentrations of these polyphenols in jabuticaba peel flours (JPFs) using HPLC as a reference method. Cyanidin-3-glucoside (C3G), ellagic acid (EA) and delphinidin-3-glucoside (D3G) were the main polyphenols found in the samples. The C3G contents ranged from 352.33 mg/100 g (S10) to 1008.73 mg/100 g (S22), with a strong correlation to TMA (r = 0.97; p = 0.00) and a moderate correlation to TEP (r = 0.45; p = 0.02). EA contents ranged from 163.65 mg/100 g (S23) to 334.69 mg/100 g (S11), with a moderate to strong correlation to TEP (r = 0.69; p = 0.00). The D3G values ranged from 94.99 mg/100 g (S10) to 203.36 mg/100 g (S5), with strong correlations to TMA (r = 0.91; p = 0.00) and C3G levels (r = 0.92; p = 0.00). The developed partial least squares-PLS models based on FTIR data provided satisfactory predictions of C3G and EA levels, reasonably matching those of HPLC.

Biosynthesis and Characterization of Gold and Copper Nanoparticles from Salvadora persica Fruit Extracts and Their Biological Properties

Introduction

Metal nanoparticle synthesis using plant has emerged as an eco-friendly, clean, and viable strategy alternative to chemical and physical approaches.

Methods

The fruit extract of Salvadora persica (SP) was utilized as a reducing and stabilizing agent in the synthesis of gold (AuNPs) and copper (CuNPs) nanoparticles.

Results

UV-Vis spectra of the AuNPs and CuNPs showed peaks at the wavelengths of 530 nm and 440 nm, respectively. Transmission electron microscopy showed that nanoparticles exhibited a mainly spherical form, with a distribution range of 100 to 113 nm in diameter for AuNPs and of 130 to 135 nm in diameter for CuNPs. While energy-dispersive X-ray spectroscopy was able to confirm the existence of AuNPs and CuNPs. The alcoholic extract of the fruit SP was analyzed by GC-MS in order to identify whether or not it contained any active phytochemicals. Fourier-transform infrared spectra confirmed the presence capping functional biomolecules of SP on the surface of nanoparticles that acts as stabilizers. Analysis of the zeta potential revealed that NPs with high degree of stability, as demonstrated by a strong negative potential value in the range of 25.2 to 28.7 mV. Results showed that both green AuNPs and CuNPs have potential antimicrobial activity against human pathogens such gram-negative bacteria and gram-positive bacteria, with CuNPs having antimicrobial activity higher than AuNPs. In addition, AuNPs and CuNPs have promising antioxidant and anticancer properties when applied to MCF-7 and MDA-MB-231 breast cancer cells. Studies of molecular docking of SP bioactive compounds were conducted against methenyl tetrahydrofolate synthetase. Among all of them, Beta - Sitosterol was the most prominent.

Conclusion

These AuNPs and CuNPs are particularly appealing in a variety of applications in the pharmaceutical and medicinal industries due to their economical and environmentally friendly production.

Fourier transform infrared spectrum pre-processing technique selection for detecting PYLCV-infected chilli plants

Pre-processing is a crucial step in analyzing spectra from Fourier transform infrared (FTIR) spectroscopy because it can reduce unwanted noise and enhance system performance. Here, we present the results of pre-processing technique optimization to facilitate the detection of pepper yellow leaf curl virus (PYLCV)-infected chilli plants using FTIR spectroscopy. Optimization of a range of pre-processing techniques was undertaken, namely baseline correction, normalization (standard normal variate, vector, and min-max), and de-noising (Savitzky-Golay (SG) smoothing, 1st and 2 derivatives). The pre-processing was applied to the mid-infrared spectral range (4000 - 400 cm^-1) and the biofingerprint region (1800 - 900 cm^-1) then the discrete wavelet transform (DWT) was used for dimension reduction. The pre-processed data were then used as an input for classification using a multilayer perceptron neural network, a support vector machine, and linear discriminant analysis. The pre-processing method with the highest classification model accuracy was selected for the further use in the processing. It was seen that only the SG 1st derivative method applied to both wavenumber ranges could produce 100% accuracy. This result was supported by principal component analysis clustering. Thus, we have demonstrated that by using the right pre-processing technique, classification success can be increased, and the process simplified by optimization and minimization of the technique used.

S-Adenosyl-L-Methionine and Cu(II) Impact Green Plant Regeneration Efficiency

The biological improvement of triticale, a cereal of increasing importance in agriculture, may be accelerated via the production of doubled haploid lines using in vitro culture. Among the relevant factors affecting the culture efficiency are Cu(II) or Ag(I) acting, e.g., as cofactors of enzymes. The copper ions are known to positively affect green plant regeneration efficiency. However, the biochemical basis, mainly its role in the generation of in vitro-induced genetic and epigenetic variation and green plant regeneration efficiency, is not well understood. Here, we employed structural equation modeling to evaluate the relationship between de novo DNA methylation affecting the asymmetric context of CHH sequences, the methylation-sensitive Amplified Fragment Length Polymorphism related sequence variation, and the concentration of Cu(II) and Ag(I) ions in induction media, as well as their effect on S-adenosyl-L-methionine perturbations, observed using FTIR spectroscopy, and the green plant regeneration efficiency. Our results allowed the construction of a theory-based model reflecting the biological phenomena associated with green plant regeneration efficiency. Furthermore, it is shown that Cu(II) ions in induction media affect plant regeneration, and by manipulating their concentration, the regeneration efficiency can be altered. Additionally, S-adenosyl-L-methionine is involved in the efficiency of green plant regeneration through methylation of the asymmetric CHH sequence related to de novo methylation. This shows that the Yang cycle may impact the production of green regenerants.

Bacterial cellulose films production by Kombucha symbiotic community cultured on different herbal infusions

The symbiotic community of bacteria and yeast (SCOBY) of Kombucha beverage produces a floating film composed of bacterial cellulose, a distinctive biobased material. In this work, Kombucha fermentation was carried out in six different herbal infusions, where SCOBY was able to synthesise cellulosic films. Infusions of black and green tea, yerba mate, lavender, oregano and fennel added with sucrose (100 g/l) were used as culture media. In all cultures, film production resulted in a maximum after 21 days. Yield conversion, process productivity and antioxidant activity were quantified. Macroscopic and microscopic features of films were determined based on electronic microscopy, calorimetric and mechanical properties and hydration behaviour. Native films from yerba mate had a remarkable antioxidant activity of 93 ± 4% of radical inhibition due to plant polyphenols, which could prevent food oxidation. Results revealed that films retained natural bioactive substances preserving important physicochemical properties, essential for developing active materials.

An Overview of the Successful Application of Vibrational Spectroscopy Techniques to Quantify Nutraceuticals in Fruits and Plants

Vibrational spectroscopy techniques are the most used techniques in the routine analysis of foods. This technique is widely utilised to measure and monitor the proximate chemical composition (e.g., protein, dry matter, fat and fibre) in an array of agricultural commodities, food ingredients and products. Developments in optics, instrumentation and hardware concomitantly with data analytics, have allowed for the progress in novel applications of these technologies in the field of nutraceutical and bio compound analysis. In recent years, several studies have demonstrated the capability of vibrational spectroscopy to evaluate and/or measure these nutraceuticals in a broad selection of fruit and plants as alternative to classical analytical approaches. This article highlights, as well as discusses, the challenges and opportunities that define the successful application of vibrational spectroscopy techniques, and the advantages that these techniques have to offer to evaluate and quantify nutraceuticals in fruits and plants.

Response of physiological parameters in Dionaea muscipula J. Ellis teratomas transformed with rolB oncogene

BACKGROUND

Plant transformation with rol oncogenes derived from wild strains of Rhizobium rhizogenes is a popular biotechnology tool. Transformation effects depend on the type of rol gene, expression level, and the number of gene copies incorporated into the plant's genomic DNA. Although rol oncogenes are known as inducers of plant secondary metabolism, little is known about the physiological response of plants subjected to transformation.

RESULTS

In this study, the physiological consequences of rolB oncogene incorporation into the DNA of Dionaea muscipula J. Ellis was evaluated at the level of primary and secondary metabolism. Examination of the teratoma (transformed shoots) cultures of two different clones (K and L) showed two different strategies for dealing with the presence of the rolB gene. Clone K showed an increased ratio of free fatty acids to lipids, superoxide dismutase activity, synthesis of the oxidised form of glutathione, and total pool of glutathione and carotenoids, in comparison to non-transformed plants (control). Clone L was characterised by increased accumulation of malondialdehyde, proline, activity of superoxide dismutase and catalase, total pool of glutathione, ratio of reduced form of glutathione to oxidised form, and accumulation of selected phenolic acids. Moreover, clone L had an enhanced ratio of total triglycerides to lipids and accumulated saccharose, fructose, glucose, and tyrosine.

CONCLUSIONS

This study showed that plant transformation with the rolB oncogene derived from R. rhizogenes induces a pleiotropic effect in plant tissue after transformation. Examination of D. muscipula plant in the context of transformation with wild strains of R. rhizogenes can be a new source of knowledge about primary and secondary metabolites in transgenic organisms.

Pungent and volatile constituents of dried Australian ginger

Ginger is well known for its pungent flavour and health-benefitting properties, both of which are imparted by various gingerol derivatives and other volatile constituents. Although there has been a considerable amount of research into the chemical constituents found in fresh ginger, there is little information available on the quality of Australian-grown dried ginger, particularly that intended for processing purposes. Here, we investigate differences in the chemical composition of three samples of processing-grade ginger, ranging from very poor to good quality. Gingerols and 6-shogaol were quantified using high performance liquid chromatograph (HPLC), while gas chromatography coupled with mass spectrometry (GC-MS) was used to identify and semi-quantify the volatile constituents and other gingerol derivatives. Significant differences were found between the samples in their content of gingerols and [6]-shogaol, as well as in their total phenolic content and antioxidant capacity. A total of 100 volatile compounds were identified in the dried ginger samples, including 54 terpenoid derivatives and 35 gingerol derivatives. Several compounds are reported from ginger for the first time, including limonene glycol and neryl laurate. In addition, we provide the second report of the presence of shyobunol, geranyl-p-cymene and geranyl-α-terpinene in ginger.

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Pungent and volatile compounds studied in ginger of varying quality.

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Several volatile compounds reported from ginger for the first time.

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Samples varied significantly in gingerol, [6]-shogaol and volatile content.

Phytochemicals and Amino Acids Profiles of Selected sub-Saharan African Medicinal Plants' Parts Used for Cardiovascular Diseases' Treatment

For years, the focus on the lipid-atherosclerosis relationship has limited the consideration of the possible contribution of other key dietary components, such as amino acids (AAs), to cardiovascular disease (CVD) development. Notwithstanding, the potential of plant-based diets, some AAs and phytochemicals to reduce CVDs' risk has been reported. Therefore, in this study, the phytochemical and AA profiles of different medicinal plants' (MPs) parts used for CVDs' treatment in sub-Saharan Africa were investigated. Fourier-transform infrared analysis confirmed the presence of hydroxyl, amino and other bioactive compounds' functional groups in the samples. In most of them, glutamic and aspartic acids were the most abundant AAs, while lysine was the most limiting. P. biglobosa leaf, had the richest total branched-chain AAs (BCAAs) level, followed by A. cepa bulb. However, A. cepa bulb had the highest total AAs content and an encouraging nutraceutical use for adults based on its amino acid score. Principal component analysis revealed no sharp distinction between the AAs composition of MPs that have found food applications and those only used medicinally. Overall, the presence of medicinally important phytochemicals and AAs levels in the selected MPs' parts support their use for CVDs treatment as they might not add to the AAs (e.g., the BCAAs) burden in the human body.

Spectroscopy NIR and MIR toward predicting simultaneous phenolic contents and antioxidant in red propolis by multivariate analysis

Conventional methods for determining phenolics and their bioactive properties are expensive, time-consuming, and laborious. This hinders the quality control of red propolis, recognized for having different types of phenolic constituents with different bioactive properties, for example, its antioxidant properties. In this sense, we present a new application of near and medium infrared spectroscopy to predict phenolic constituents, total flavonoids, gallic acid, kaempferol, pyrocatechin, quercetin, and different antioxidant tests (DPPH radical, reducing power and protection of the β-carotene: linoleic acid system) of red propolis using chemometry. The optimized models showed good predictive capacity with a minimum correlation coefficient of 0.70, low associated error, and figures of merit that indicate the good predictive capacity in the validation of the models. These data show infrared spectroscopy as efficient to simultaneously predict nine quality analyzes of red propolis quickly and simply. This also avoids tedious procedures for traditional chromatographic and spectrophotometric tests.

A cut above the rest: oxidative stress in chronic wounds and the potential role of polyphenols as therapeutics

OBJECTIVES

The pathophysiology of chronic wounds typically involves redox imbalance and inflammation pathway dysregulation, often with concomitant microbial infection. Endogenous antioxidants such as glutathione and tocopherols are notably reduced or absent, indicative of significant oxidative imbalance. However, emerging evidence suggests that polyphenols could be effective agents for the amelioration of this condition. This review aims to summarise the current state of knowledge surrounding redox imbalance in the chronic wound environment and the potential use of polyphenols for the treatment of chronic wounds.

KEY FINDINGS

Polyphenols provide a multi-faceted approach towards the treatment of chronic wounds. Firstly, their antioxidant activity allows direct neutralisation of harmful free radicals and reactive oxygen species, assisting in restoring redox balance. Upregulation of pro-healing and anti-inflammatory gene pathways and enzymes by specific polyphenols further acts to reduce redox imbalance and promote wound healing actions, such as proliferation, extracellular matrix deposition and tissue remodelling. Finally, many polyphenols possess antimicrobial activity, which can be beneficial for preventing or resolving infection of the wound site.

SUMMARY

Exploration of this diverse group of natural compounds may yield effective and economical options for the prevention or treatment of chronic wounds.

Aerogels based on corn starch as carriers for pinhão coat extract (Araucaria angustifolia) rich in phenolic compounds for active packaging

The objective of this study was to produce renewable aerogels from native and anionic corn starches loaded with pinhão coat extract (PCE) with water absorbent capacity, antioxidant activity and controlled release of phenolic compounds in a hydrophilic food simulant media. Starch aerogels were produced with different concentrations of PCE, 5 and 10%, and evaluated for FT-IR spectra, relative crystallinity, thermal properties, water absorption capacity (WAC), density, antioxidant activity and in vitro release. Thermal stability of the compounds was improved by the incorporation of PCE. The aerogels presented high WAC of 541 to 731% and low-density values of 0.03 g.cm^-1. The highest inhibition of DPPH and ABTS radicals was presented to anionic starch aerogels with 10% PCE rendering 26% of inhibition of ABTS and 24% of DPPH. The maximum in vitro releases for native and anionic starch aerogels with 5% of PCE were 28.70 and 29.44%, respectively, and for aerogels with 10% of PCE they were 34.27 and 35.94%, respectively. The anionic starch aerogels had the highest amount of phenolic compounds released when compared to the native starch aerogels. The starch-based bioactive aerogels showed potential to be applied in food packaging as water absorbent and as a carrier of phenolic compounds.

Determination of the Dependence of Thermal Diffusivity with Moringa Concentration by Thermal Lens as a Sensitive Experimental Technique

The use of photothermal techniques has become of special importance due to their versatile application in the thermal characterization of materials. Therefore, the thermal lens technique in the mismatched dual-beam mode is an alternative, sensitive and non-evasive tool that was used in this research to determine the thermal diffusivity of Moringa oleifera. The dual arrangement of the thermal lens technique is based on the use of an Ar+Xe excitation laser (422 nm) and a He-Ne laser (632 nm) test laser. Moringa solutions were prepared by green synthesis with different concentrations ranging from 1.56 mg·mL-1, 3.12 mg·mL-1, 6.25 mg·mL-1 to 12.50 mg·mL-1. Different optical techniques (UV-vis, FTIR, XPS and EDS) were used to characterize the Moringa leaf powders. Results showed that the increase of thermal diffusivity could be related to the presence of functional groups and metallic elements in Moringa elemental composition. In this work, it was found that the thermal diffusivity of Moringa increases with increasing concentration. This study will be useful for application in heat transport and drug release.