Silicon's Influence on Polyphenol and Flavonoid Profiles in Pea (Pisum sativum L.) under Cadmium Exposure in Hydroponics: A Study of Metabolomics, Extraction Efficacy, and Antimicrobial Properties of Extracts.

The current study aimed to investigate the impact of silicon (Si) supplementation in the form of Na2SiO3 on the metabolome of peas under normal conditions and following exposure to cadmium (Cd) stress. Si is known for its ability to enhance stress tolerance in various plant species, including the mitigation of heavy metal toxicity. Cd, a significant contaminant, poses risks to both human health and the environment. The study focused on analyzing the levels of bioactive compounds in different plant parts, including the shoot, root, and pod, to understand the influence of Si supplementation on their biosynthesis. Metabolomic analysis of pea samples was conducted using a targeted HPLC/MS approach, enabling the identification of 15 metabolites comprising 9 flavonoids and 6 phenolic acids. Among the detected compounds, flavonoids, such as flavon and quercetin, along with phenolic acids, including chlorogenic acid and salicylic acid, were found in significant quantities. The study compared Si supplementation at concentrations of 1 and 2 mM, as well as Cd stress conditions, to evaluate their effects on the metabolomic profile. Additionally, the study explored the extraction efficiency of three different methods: accelerated solvent extraction (ASE), supercritical fluid extraction (SFE), and maceration (MAC). The results revealed that SFE was the most efficient method for extracting polyphenolic compounds from the pea samples. Moreover, the study investigated the stability of polyphenolic compounds under different pH conditions, ranging from 4.0 to 6.0, providing insights into the influence of the pH on the extraction and stability of bioactive compounds.

The Multifaceted Roles of Bovine Lactoferrin: Molecular Structure, Isolation Methods, Analytical Characteristics, and Biological Properties.

Bovine lactoferrin (bLF) is widely known as an iron-binding glycoprotein from the transferrin family. The bLF molecule exhibits a broad spectrum of biological activity, including iron delivery, antimicrobial, antiviral, immunomodulatory, antioxidant, antitumor, and prebiotic functions, thereby making it one of the most valuable representatives for biomedical applications. Remarkably, LF functionality might completely differ in dependence on the iron saturation state and glycosylation patterns. Recently, a violently growing demand for bLF production has been observed, mostly for infant formulas, dietary supplements, and functional food formulations. Unfortunately, one of the reasons that inhibit the development of the bLF market and widespread protein implementation is related to its negligible amount in both major sources─colostrum and mature milk. This study provides a comprehensive overview of the significance of bLF research by delineating the key structural characteristics of the protein and elucidating their impact on its physicochemical and biological properties. Progress in the development of optimal isolation techniques for bLF is critically assessed, alongside the challenges that arise during its production. Furthermore, this paper presents a curated list of the most relevant instrumental techniques for the characterization of bLF. Lastly, it discusses the prospective applications and future directions for bLF-based formulations, highlighting their potential in various fields.

Metal tolerance and Cd phytoremoval ability in Pisum sativum grown in spiked nutrient solution.

In the presented study, the effects of cadmium (Cd) stress and silicon (Si) supplementation on the pea plant (Pisum sativum L.) were investigated. The tendency to accumulate cadmium in the relevant morphological parts of the plant (roots and shoots respectively)-bioaccumulation, the transfer of this element in the plant (translocation) and the physiological parameters of the plant through indicators of oxidative stress were determined. Model studies were carried out at pH values 6.0 and 5.0 plant growth conditions in the hydroponic cultivation. It was shown that Cd accumulates mostly in plant roots at both pH levels. However, the Cd content is higher in the plants grown at lower pH. The Cd translocation factor was below 1.0, which indicates that the pea is an excluder plant. The contamination of the plant growth environment with Cd causes the increased antioxidant stress by the growing parameters of the total phenolic content (TPC), polyphenol oxidase activity (PPO), the malondialdehyde (MDA) and lipid peroxidation (LP). The results obtained showed that the supplementation with Si reduces these parameters, thus lowering the oxidative stress of the plant. Moreover, supplementation with Si leads to a lower content of Cd in the roots and reduces bioaccumulation of Cd in shoots and roots of pea plants.

Synthesis and physicochemical characterization of bovine lactoferrin supersaturated complex with iron (III) ions.

The aim of the study was to investigate the process of Fe3+ binding to bLTF. Moreover, the physicochemical characterization of the respective supersaturated complex was studied. The knowledge should be important for the description of processes that may take place in dairy products fortified with iron. Additionally, the synthesized complex can be utilized as a dietary supplement for the treatment of iron deficiency anemia (IDA). Finally, it was shown that formation of supersaturated iron-protein structures which include LTF often accompanies development of neurodegenerative diseases such as Alzheimer or Parkinson. Thus, the study can reveal some aspects of its pathogenesis process. The methodology of the investigation comprised the utilization of batch sorption study and applying Freundlich and Langmuir models. The complex also was characterized by numerous techniques: spectrometric (ICP-MS), spectroscopic (UV-Vis, ATR-FTIR), electron microscopy (TEM-EDX), SDS-PAGE. Based on obtained results the potential mechanisms of iron interaction with protein were described. Moreover, the molecular docking was applied to visualize possible metal binding sites. The respective complex contains ≈ 33.0 mg/g of iron which is nearly 50 Fe3+ per one protein molecule. The cytotoxicity of the obtained complex was evaluated by MTT reduction and LDH release assays on Caco-2 and nL929 cell lines.

Capillary Zone Electrophoresis in Tandem with Flow Cytometry in Viability Study of Various ATCC Bacterial Strains under Antibiotic Treatment.

The aim of this study was to develop an innovative method of examining bacterial survival using capillary zone electrophoresis (CZE) and flow cytometry (FC) as a reference method. For this purpose, standard strains of bacteria from the ATCC collection were used: Enterococcus faecalis ATCC 14506, Staphylococcus aureus ATCC 11632, Klebsiella pneumoniae ATCC 10031, Pseudomonas aeruginosa ATCC 27853, and Escherichia coli ATCC 25922, as well as seven antibiotics with different antimicrobial mechanisms of action. The ratio of live and dead cells in the tested sample in CZE measurements were calculated using our algorithm that takes into account the detection time. Results showed a high agreement between CZE and FC in the assessment of the percentage of live cells exposed to the stress factor in both antibiotic susceptibility and time-dependent assays. The applied measuring system to assess the effectiveness of antibiotic therapy in in vitro conditions is a method with great potential, and the data obtained with the use of CZE mostly correspond to the expected drug sensitivity according to EUCAST and CLSI guidelines.

Comparison Study of Cytotoxicity of Bare and Functionalized Zinc Oxide Nanoparticles.

In this paper, a study of the cytotoxicity of bare and functionalized zinc oxide nanoparticles (ZnO NPs) is presented. The functionalized ZnO NPs were obtained by various types of biological methods including microbiological (intra- and extracellular with Lactobacillus paracasei strain), phytochemical (Medicago sativa plant extract) and biochemical (ovalbumin from egg white protein) synthesis. As a control, the bare ZnO NPs gained by chemical synthesis (commercially available) were tested. The cytotoxicity was measured through the use of (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) dye as well as lactate dehydrogenase (LDH) assays against murine fibroblast L929 and Caco-2 cell lines. As a complementary method, scanning electron microscopy (SEM) was performed to assess the morphology of the tested cells after treatment with ZnO NPs. The microscopic data confirmed the occurrence of apoptotic blebbing and loss of membrane permeability after the administration of all ZnO NPs. The reactive oxygen species (ROS) concentration during the cell lines' exposure to ZnO NPs was measured fluorometrically. Additionally, the photocatalytic degradation of methylene blue (MB) dye in the different light conditions, as well as the antioxidant activity of bare and functionalized ZnO NPs, is also reported. The addition of all types of tested ZnO NPs to methylene blue resulted in enhanced rates of photo-degradation in the presence of both types of irradiation, but the application of UV light resulted in higher photocatalytic activity of ZnO NPs. Furthermore, bare (chemically synthetized) NPs have been recognized as the strongest photocatalysts. In the context of the obtained results, a mechanism underlying the toxicity of bio-ZnO NPs, including (a) the generation of reactive oxygen species and (b) the induction of apoptosis, is proposed.

Metabolic Profiling of VOCs Emitted by Bacteria Isolated from Pressure Ulcers and Treated with Different Concentrations of Bio-AgNPs.

Considering the advent of antibiotic resistance, the study of bacterial metabolic behavior stimulated by novel antimicrobial agents becomes a relevant tool to elucidate involved adaptive pathways. Profiling of volatile metabolites was performed to monitor alterations of bacterial metabolism induced by biosynthesized silver nanoparticles (bio-AgNPs). Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae and Proteus mirabilis were isolated from pressure ulcers, and their cultures were prepared in the presence/absence of bio-AgNPs at 12.5, 25 and 50 µg mL-1. Headspace solid phase microextraction associated to gas chromatography-mass spectrometry was the employed analytical platform. At the lower concentration level, the agent promoted positive modulation of products of fermentation routes and bioactive volatiles, indicating an attempt of bacteria to adapt to an ongoing suppression of cellular respiration. Augmented response of aldehydes and other possible products of lipid oxidative cleavage was noticed for increasing levels of bio-AgNPs. The greatest concentration of agent caused a reduction of 44 to 80% in the variety of compounds found in the control samples. Pathway analysis indicated overall inhibition of amino acids and fatty acids routes. The present assessment may provide a deeper understanding of molecular mechanisms of bio-AgNPs and how the metabolic response of bacteria is untangled.

Combination of electrochemical unit and ESI-MS in fragmentation of flavonoids.

INTRODUCTION: Predictive approaches on the activity of natural compounds based on the fragmentation by instrumental techniques are important for consideration of such molecules as drug candidates and defining new structures with promising properties. Since flavonoids are well-known antioxidants, their redox properties can be related to their pharmacological activity. OBJECTIVES: In this work, the potential of electrochemical unit coupled to electrospray ionisation mass spectrometry (ESI-MS) was assessed for fragmentation activity relationships studies of selected flavonoids. METHODOLOGY: Methodology of this research included electrochemical conversion of standards of flavonoids at different pH values and their further analysis with the use of ESI-MS. In addition, signals obtained from the blank samples were also identified and used for interpretation due to electrochemical nature of the ESI source. Half maximal inhibitory concentration (IC50 ) values of flavonoids for 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant activity assays were analysed for possible correlation with the structures of flavonoids and products of electrochemical conversion. RESULTS: Fragmentation activity relationships were suggested using the proposed approach and for some of the flavonoids it was not specific enough to determine the input of a particular structural feature to the activity, but for others they were in agreement with those found in the literature. Obtained results showed potential of the proposed approach for application in plant sciences as a fast pre-screening tool for newly isolated bioactive compounds.

Interactions of Whey Proteins with Metal Ions.

Whey proteins tend to interact with metal ions, which have implications in different fields related to human life quality. There are two impacts of such interactions: they can provide opportunities for applications in food and nutraceuticals, but may lead to analytical challenges related to their study and outcomes for food processing, storage, and food interactions. Moreover, interactions of whey proteins with metal ions are complicated, requiring deep understanding, leading to consequences, such as metalloproteins, metallocomplexes, nanoparticles, or aggregates, creating a biologically active system. To understand the phenomena of metal-protein interactions, it is important to develop analytical approaches combined with studies of changes in the biological activity and to analyze the impact of such interactions on different fields. The aim of this review was to discuss chemistry of ß-lactoglobulin, α-lactalbumin, and lactotransferrin, their interactions with different metal ions, analytical techniques used to study them and the implications for food and nutraceuticals.

Effect of solvent and extraction technique on composition and biological activity of Lepidium sativum extracts.

The aim of this study was to evaluate chemical and biological potential of garden cress (Lepidium sativum L.) to receive valuable plant extracts with potential application in pharmacy or food industry. Four techniques of extraction and three environmentally friendly solvents such as water, supercritical CO2 and ethanol have been tested. Biological activity and chemical profile were evaluated in obtained extracts. GC/MS analysis showed that SFE extract from dried sprouts of L. sativum was especially rich in such glucosinolate derivatives as benzyl cyanide and benzyl thiocyanate. However, the extract obtained from freeze-dried sprouts by SFE with addition of 96% ethanol as co-solvent was especially rich in flavonoids and simultaneously exhibited the best antimicrobial activity. Comparison of MALDI-TOF-MS spectra of all obtained extracts clearly indicates that both SFE and maceration with water are the most selective techniques of extraction due to the lowest level of interfering substances with high molecular masses.

New approach for fast identification of cyclitols by MALDI-TOF mass spectrometry.

INTRODUCTION: Alfalfa (Medicago sativa L.) is the subject of many studies due to its numerous chemical constituents and beneficial properties. Among these constituents are cyclitols, which have attracted attention due to the variety of biological properties they have. OBJECTIVE: A rapid and sensitive analytical procedure based on matrix-assisted laser desorption ionisation technique with time-of-flight and mass spectrometry (MALDI-TOF-MS) analysis was used for the first time for the identification of three cyclitols from different parts of alfalfa. METHODOLOGY: Plant extracts were prepared and purified using Soxhlet extraction and solid-phase extraction (SPE). Then, samples were dissolved in α-cyano-4-hydroxycinnamic acid (HCCA) matrix, and subjected to MALDI-TOF-MS analysis. RESULTS: The ion at m/z 524.0 was distributed in all standards and in leaves and stem extracts. In turn, the signal at m/z 335.1 was found in all standards and all alfalfa extracts. The ion at m/z144.1 was found just for d-chiro-inositol and distributed in all extracts. Both signals at m/z 265.9 and 250.0 were found only in l-chiro-inositol standard and the extract of stem. However, the ion at m/z 177.1 was found in d-pinitol standard and the extract of leaves. Based on molecular weights, information on fragment ions obtained by MALDI-TOF-MS, and the chemistry of cyclitols, we successfully identified three cyclitols (d-chiro-inositol, l-chiro-inositol, d-pinitol) in different parts of alfalfa (leaves, stem, flowers). CONCLUSION: The obtained results in this study proved that MALDI-TOF-MS is a rapid, sensitive and very powerful tool for identification of cyclitols within plants and has the potential to differentiate between enantiomers.