Chromatographic assessment of biodiesel production from Peganum harmala seed oil using environmentally benign nano-catalysts

This work gives a comprehensive chromatographic assessment of biodiesel generation from plant seed oil using ecologically friendly nano-catalysts. Researchers all over the world are actively looking for new ways to satisfy the urgent need for clean and renewable energy sources. The resultant biodiesel was fully characterized utilizing modern techniques like scanning electron microscopy, energy diffraction X-ray and X-ray diffraction. The biodiesel gas chromatography/mass spectrometry analysis revealed four significant peaks of fatty acid methyl esters, indicating high-quality biodiesel production. Furthermore, the biodiesel fuel qualities were discovered to be comparable with international standards such as ASTM D-6571 and EN-14214. This indicates that the iron-modified clay nano-catalyst can be used as a catalyst for large-scale biodiesel production. This work is important because it could lead to the large-scale production of a novel, non-food feedstock. We may lessen our reliance on fossil fuels and contribute to a more sustainable and ecologically friendly energy future by leveraging the usage of biodiesel produced in this way. The chromatographic assessment of biodiesel production from non-edible seed oil using environmentally benign nano-catalysts holds significant promise in advancing sustainable and eco-friendly biodiesel production methods, contributing to a cleaner and more environmentally responsible energy sector.

Immunostimulatory and anti-inflammatory impact of Fragaria ananassa methanol extract in a rat model of cadmium chloride-induced pulmonary toxicity

Cadmium is an extremely dangerous heavy metal that can lead to disastrous consequences in all organisms. Several natural remedies reduce the toxicities of experimentally generated metals in animals. Strawberry Fragaria ananassa contains several bioactive compounds that may mitigate heavy-metal toxicity. The study aim was to evaluate the ability of a strawberry fruit methanol extract (SE) to reduce Cd toxicity and to identify and quantify the active constituents of SE. Forty Wistar rats were classified into four groups: the control group- 1 ml saline IP; SE group- 100 mg of SE/kg rats orally; cadmium (Cd) group-2 mg CdCl2/kg body weight/IP daily; and treated group- SE given 1 hour before Cd administration. Administration of Cd induced several histopathological and immunohistochemical alterations in lung sections. Biochemical analysis of lung homogenates and mRNA levels of antioxidants and inflammatory cytokines indicated significant changes to the risk profile. SE administration significantly decreased the oxidative stress, inflammation, tissue damage, the mean area percentage of collagen fibers, and positive immuno-expressions of TNF-α and NF-κB induced by CdCl2. Moreover, the MDA, TNF-α, GM-CSF, and IL-1β levels in Cd-exposed rat lung tissue were significantly lower in the SE-treated group than in the Cd-group. SE significantly augmented lung GSH, SOD, HO-1, GPx-2, and Nrf2 levels in Cd-exposed rats. SE mitigated Cd-caused oxidative stress and lung inflammation. Therefore, regularly consuming a strawberry-rich diet could benefit general health and help prevent and treat diseases.

Dietary Kynurenine Pathway Metabolites-Source, Fate, and Chromatographic Determinations

Tryptophan metabolism plays an essential role in human health. In mammals, about 95% of dietary tryptophan is metabolized through the kynurenine pathway, which is associated with the development of several pathologies, including neurodegeneration. Some of the kynurenine pathway metabolites are agonists of the aryl hydrocarbon receptor involved in metabolic functions, inflammation, and carcinogenesis. Thus, their origins, fates, and roles are of widespread interest. Except for being produced endogenously, these metabolites can originate from exogenous sources (e.g., food) and undergo absorption in the digestive tract. Recently, a special focus on exogenous sources of tryptophan metabolites was observed. This overview summarizes current knowledge about the occurrence of the kynurenine pathway metabolites (kynurenines) in food and the analytical method utilized for their determination in different food matrices. Special attention was paid to sample preparation and chromatographic analysis, which has proven to be a core technique for the detection and quantification of kynurenines. A discussion of the fate and role of dietary kynurenines has also been addressed. This review will, hopefully, guide further studies on the impact of dietary kynurenines on human health.

Protective Effect of Urtica dioica Extract against Oxidative Stress in Human Skin Fibroblasts

Urtica dioica is a species with well-established significance in folk medicine in many countries. It was utilized to support the treatment of arthritis, allergies, and urinary tract disorders; however, the substantial presence of antioxidants suggests that nettle extract could also have a positive impact on the skin. The objective of this study was to assess the impact of nettle extract on human skin fibroblasts subjected to oxidative stress. Various solvents were tested to prepare an extract rich in polyphenolic compounds with high antioxidant potential. The chemical composition was determined using ultra-high-performance liquid chromatography with mass spectrometry (UPLC-DAD-MS). H2O2 treatment was used to induce oxidative stress and cell viability, and the metabolism was evaluated through NR and MTT assays. Our study demonstrated that extraction with 80% ethanol, followed by the drying and re-dissolving of the extract in pure water, was more efficient than direct extraction with water. This yielded an extract rich in polyphenolic compounds, with chlorogenic acid and caffeoylmalic acid as the predominant compounds, averaging 64.9 and 114.4 µg/mL, respectively. The extract exhibited antioxidant properties in the DPPH and ABTS assays. Furthermore, it did not exhibit cytotoxicity and did not negatively affect cell metabolism. In addition, it effectively reduced ROS in the H2O2-stimulated cells, and at the highest concentration tested, the ROS levels returned to those of the untreated control. The extract also protected against H2O2-induced cytotoxicity. The cell viability was maintained at the level of the untreated control when the cells were pretreated with the extract before H2O2 exposure. These findings indicate that U. dioica extract is a valuable and safe additive in skincare products.

Development, Validation, and Two-Year Application of Rapid and Simple LC-MS/MS-Based Method for the Determination of K2MK-7 in Blood Samples

Biological properties of menaquinone-7, one of the vitamin K2 vitamers (K2MK-7), both those proven and those that remain to be investigated, arouse extensive interest that goes beyond the strictly scientific framework. The most important of them is the prevention of age-related diseases, considering that we live in the times identified as the era of aging societies and many people are exposed to the vitamin K2MK-7 deficiency. Therefore, an effective analytical protocol that can be adopted as a diagnostic and preventive analytics tool is needed. Herein, a simple sample preparation method followed by the liquid chromatography-tandem mass spectrometry-based method (LC-MS/MS), was used for the selective and sensitive determination of K2MK-7 in serum samples. Under the optimized conditions, using 500 µL of serum and the same amount of n-hexane, the reproducibility and the accuracy were obtained in the ranges of 89-97% and 86-110%, respectively, and the limit of detection value was 0.01 ng/mL. This method was used for the routine analysis. Statistical interpretation of the data from 518 samples obtained during 2 years of practice allowed for obtaining information on the content and distribution of K2MK-7 in the Polish population, broken down by the sex and age groups.

Detection of Synthetic Antioxidants: What Factors Affect the Efficiency in the Chromatographic Analysis and in the Electrochemical Analysis?

Antioxidants are food additives largely employed to inhibit oxidative reactions in foodstuffs rich in oils and fat lipids, extending the shelf life of foodstuffs and inhibiting alterations in color, flavor, smell, and loss of nutritional value. However, various research has demonstrated that the inadequate use of synthetic antioxidants results in environmental and health problems due to the fact that some of these compounds present toxicity, and their presence in the human body, in high concentrations, is related to the development of some cancer types and other diseases. Therefore, the development of analytical methods for identifying and quantifying synthetic antioxidants in foodstuffs is fundamental to quality control and in ensuring consumer food safety. This review describes the recent chromatographic and electrochemical techniques used in the detection of synthetic phenolic antioxidants in foodstuffs, highlighting the main characteristics, advantages and disadvantages of these methods, and specific typical features, which include extraction methods for sample preparation and materials used in the working electrode construction, considering chromatographic and voltammetric methods, since these specific features influence the efficiency in the analysis.

Biogenic silver nanoparticles improve bioactive compounds in medicinal plant Juniperus procera in vitro

Bioactive compounds of medicinal plants present as natural ingredients provide health benefits beyond the basic nutritional value of these products. However, the availability of bioactive compounds in the current natural sources is limited. Hence, the induction of bioactive compound production from medicinal plants through nanoparticles (NPs) might play a vital role in industrially important medicinal compounds. Therefore, this study aimed to synthesize silver nanoparticles (AgNPs) biologically and to investigate their effect on phytochemical compound production from the callus of Juniperus procera. AgNPs were synthesized biologically using aqueous leaf extract of Phoenix dactylifera, which acted as a reducing and capping agent, and silver nitrate solution. The formation of AgNPs has been confirmed through different analytical techniques such as UV-Visible spectroscopy (UV), Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and scanning electron microscope (SEM). The impact of different concentrations (0.0, 5, 20, and 50 mg/L) of AgNPs on enzymatic and non-enzymatic antioxidants of the callus of J. procera was investigated. The obtained results showed a significant effect of AgNPs on biomass accumulation and non-enzymatic antioxidants (phenol, tannin, and flavonoid content). Additionally, total protein content and superoxide dismutase (SOD) activity were increased in response to AgNPs. Furthermore, bioactive compounds like gallic acid, tannic acid, coumarin, hesperidin, rutin, quercetin, and ferruginol were chromatographically separated and quantified using high-performance liquid chromatography (HPLC) with reference standards. These compounds were increased significantly in response to AgNPs treatments. We concluded that AgNPs could be a promising elicitor for improving the production of phytochemical compounds in medicinal plants. This work can serve asa good model for improving the production of bioactive compounds from medicinal plants in vitro. This molecular investigation should be done to understand better the metabolic mechanism leading to bioactive compound production scaling.

Determination of anthraquinones in Rhamnus purshiana using HPLC coupled to diode array detector and simple ultraviolet spectroscopic analysis

A new method based on Ultraviolet spectrophotometry was developed and compared with that based on HPLC for the determination and quantification of anthraquinones in the extracts of Rhamnus purshiana bark. A validated quantitative analysis of cascaroside A, cascaroside B, emodin, and aloe-emodin in these herbal products has been previously performed using HPLC coupled with diode array detector. In the HPLC analysis, all the anthraquinones showed satisfactory regression (r² > 0.98) within the test ranges, and the recovery was in the range of 94 to 117%. The limits of detection and quantification ranged from 0.008-0.010 (μg mL^-1 ) and 0.029-0.035 (μg mL^-1 ), respectively. Hierarchical cluster analysis and principal component analysis showed differences in the anthraquinones determined from herbal samples. Subsequently, a simple and low-cost ultraviolet spectrophotometric methodology for the quantitative analysis of the same compounds in the extracts was applied, and all the contents were determined. A paired t-test confirmed that there were no significant differences between the two methods. Our results revealed that the developed method is simple and provides the ability to discriminate and control the quality of anthraquinones in herbal products. This article is protected by copyright. All rights reserved.

Influence of Temperature on the Quantity of Bisphenol A in Bottled Drinking Water

Bisphenol A (BPA) is a component used in the production of polycarbonate plastics (PC) and epoxy resins, which are currently widely used in food and beverage packaging. Although BPA is not used in polyethylene terephthalate (PET) manufacturing, a recent study reported its presence in PET water bottles. This study was conducted to investigate the effects of storage conditions on the release of BPA from PET bottles as well as to assess health risks associated with the consumption of bottled water. Using high-performance liquid chromatography (HPLC), we measured the content of BPA in local brands of plastic bottled water sold in the Polish market. It has been established that temperature is one of the main factors that influences the migration of bisphenol A to products, as was confirmed by determination of the amount of bisphenol A in water, which was carried out without exposing the bottles to different temperatures. Despite the fact that the individual concentrations of BPA in bottled water were low (ng/L) at 0.6 mg/kg (body weight), the cumulative daily dose in the body may be much higher than the quoted concentrations due to the number of products containing BPA. Thus, prolonged usage of bottled water and beverages should be avoided to reduce the risk of human exposure to BPA through leaching. Additionally, it was found that high temperatures resulted in increased BPA leaching.

notoginseng extracts, and pharmacology in recent five years]

As a famous and precious Chinese medicinal material, Panax notoginseng(PN) has been commonly used for a long history in China. As reported, PN exhibits significant pharmacological actions in protecting cardiocerebral vascular system and nervous system and suppressing tumors. In recent years, with the innovation in ideas, as well as the development of methods and equipment, PN has been extensively investigated, and notable progress has been made. This paper reviewed the advancements of PN in recent five years from chemical components, chromatographic analysis, P. notoginseng extracts, and pharmacology, in which the application of PN extracts in quality control was first summarized. The present study aims to provide a theoretical basis for quality control, product development, and rational medication of PN.

Molecular docking analysis of mTOR protein kinase with chromatographically characterized compounds from Clerodendrum inerme L. leaves extract

The mTOR protein is known to be linked with cancer. Therefore, it is of interest to document the molecular docking analysis of mTOR protein kinase with chromatographically characterized compounds from Clerodendrum inerme L. leaves extract. The GC-MS analysis suggested that, totally 25 bioactive compounds were present in the extract of Clerodendrum inerme. Molecular docking analysis show that the bioactive compounds such as Triethoxysilanol, Piperazine dihydrochloridehydrate, 2,4(1H,3H)-Pyrimidinedione, 5-methyl and 4',7-Dihydroxyflavanone showed good glide score and glide energy within the acceptable and permissible limits of ADME properties for further consideration in drug discovery.

The Power of Carbon Nanotubes on Sensitive Drug Determination Methods

Nowadays, carbon nanotubes (CNTs) due to their inorganic conducting, semiconducting, and organic π-π stacking properties are becoming innovative materials. CNTs have an adjustable size, large surface area, and other significant chemical properties. Due to their excellent electrical, optical, and mechanical properties, CNTs play an important role in various application fields. In the past decade, many unique intrinsic physical and chemical properties have been intensively explored for pharmaceutical, biological, and biomedical applications. The functionalization of CNTs results in a remarkably reduced cytotoxicity and at the same time increased biocompatibility. The toxicity studies reveal that highly water-soluble and serum stable nanotubes are biocompatible, nontoxic, and potentially useful for biomedical applications. Ultrasensitive drug determination from its dosage form and/or biological samples with carbon nanotubes can be realized after surface modification. The main purpose of this review is to present recent achievements on CNTs which are investigated in electrochemical and chromatographically sensing technologies.

Genotype and Successive Harvests Interaction Affects Phenolic Acids and Aroma Profile of Genovese Basil for Pesto Sauce Production

Basil (Ocimum basilicum L.) is an essential ingredient of the Mediterranean cuisine due to its distinctive aroma. Genovese basil leaves are used to prepare "pesto", a condiment that has always caught the interest of consumers and producers. Usually, basil for industrial processing is harvested more than once to extract a higher yield. However, successive cuts can affect quality traits that play a crucial role in defining the product's final sensory profile. This research was aimed to evaluate the impact of cut on the quantitative and qualitative properties of three Genovese basil cultivars (Aroma 2, Eleonora and Italiano Classico) grown in an open field. Nitrate content, phenolic acids and aromatic profile were determined by ion chromatography (IC), high-performance liquid chromatography (HPLC), and gas chromatography coupled to a mass spectrometer (GC/MS) analysis, respectively. The second harvest increased fresh biomass and total phenolic acids content by 172% and 413%, respectively, with Italiano Classico recording the highest values. The combination of second-cut Aroma 2 yielded the lowest nitrate (473.8 mg kg-1 of fresh weight) and Eugenol (2.4%) levels. In the second harvest, Eleonora showed an increase in eugenol and trans-α-bergamotene of 75.3% and 48.2%, respectively; whereas, eucalyptol and β-cis-ocimene decreased by 34.4% and 51.6%, respectively. Although successive harvests may increase basil yield and quality overall, the cultivar-dependent response to successive cuts needs to be accounted for in order to accomplish standardization of industrial "pesto" sauce.

Identification of Phenolic Compounds and Determination of Antioxidant Activity in Extracts and Infusions of Salvia Leaves

The influence of harvest period and drying method of Salvia officinalis L. leaves on the content of essential oils, polyphenols and antioxidant properties was investigated. Sage leaves were collected twice during plant blossoming (in June and July) and dried traditionally in natural conditions and at 35 °C. Antioxidant activity was assayed in methanol-acetone extracts and infusions of dried leaves with the use of free radical scavenging activity (DPPH) and ferric reducing antioxidant power (FRAP) technique. Total phenolic content in extracts as well as in infusions was determined by the means of Folin-Ciocalteu method. Based on the LC/MS analysis, the polyphenol compounds present in both extracts and in infusions were identified. The extracts contained more polyphenols and were characterized by higher antioxidant activity than infusions. In the extracts significant amount of ferulic acid was found, which was influenced both by the harvest period and drying method. The amount of ferulic acid found in extracts obtained from the June leaves dried traditionally was three times lower (6.185 μg/g DW) than in extracts from July leaves dried in the same conditions. Harvest period had a significant effect on the essential oils' content, leaves collected in July contained 15% more oils than those collected in June.

In Vitro Anthelminthic Efficacy of Aqueous Pomegranate (Punica granatum L.) Extracts against Gastrointestinal Nematodes of Sheep

The worldwide increased difficulty to counteract gastrointestinal nematode (GIN) infection in sheep, due to progressing anthelmintic resistance, has led to the evaluation of other alternative helminth control options, mainly from plants. The anthelmintic efficacy of an aqueous Punica granatum macerate was evaluated in sheep naturally infected by GIN in southern Italy. The macerate was chemically characterized by chromatographic analysis coupled with high-resolution mass spectrometry (LC/HRMS) and an aliquot was concentrated to obtain a dry extract. A part was characterized, the remaining washed with methanol to obtain an insoluble residue and methanol phase. In the methanol fraction, the quantitatively predominant gallic acid was purified to obtain the pure molecule. The three fractions thus obtained were used for in vitro studies (i.e., egg hatch test) to verify anthelmintic efficacy. For this purpose, fecal samples were collected from sheep naturally infected by GINs. Fractions were diluted in H₂O/DMSO 0.5% at 1.00, 0.5, 0.25, 0.125, 0.05, and 0.005 mg/mL concentrations. Thiabendazole (0.25 and 0.5 mg/mL) and deionized water were used as positive and negative controls, respectively. Egg hatch test results indicated that all fractions caused a significant (p < 0.05) egg hatch inhibition within 48 h of exposure highlighting a high (>82%) efficacy in vitro at all tested doses. Maximal egg hatching inhibition effect was exhibited by the methanol fraction (99.3% and 89.3% at 1 and 0.005 mg/mL concentrations), followed by the insoluble residue and gallic acid (94.7% and 85.3% and 94.0% and 82.7% at 1 and 0.005 mg/mL, respectively). The current study validated the anthelmintic potential of traditional P. granatum macerate against GIN infection in sheep, thus highlighting the role of gallic acid as principal component and justifying a need to undertake further in vivo studies on these ethno-veterinary remedies.

Recovery of Bioactive Compounds from Hazelnuts and Walnuts Shells: Quantitative-Qualitative Analysis and Chromatographic Purification

Hazelnut (HS) and walnut (WS) shells, an abundant by-product of the processing industries of these edible nuts, are traditionally considered as a low-value waste. However, they are a source of valuable compounds with an interesting chemical profile for the chemical and pharmaceutical sectors. In this study, the lipophilic and hydrophilic extracts present in HS and WS were quantified and identified, then the polar fractions were chromatographically separated, and their antioxidant capacity was studied. The experimental work includes the isolation of crude lipophilic and hydrophilic extracts by an accelerated extraction process, chromatographic analysis (gas chromatography-flame ionization (GC-FID), GC-mass spectroscopy (GC-MS), high-performance size-exclusion chromatography (HPSEC), thin-layer chromatography (TLC)), and quantification of the components. In addition, a thorough compositional characterization of the subgroups obtained by flash chromatography and their antioxidant capacity was carried out. The gravimetric concentrations showed different lipophilic/hydrophilic ratios (0.70 for HS and 0.23 for WS), indicating a higher proportion of polar compounds in WS than in HS. Moreover, the lipophilic extracts were principally composed of short-chain fatty acids (stearic, palmitic, and oleic acid), triglycerides, and sterols. The polar fractions were screened by thin-layer chromatography and then separated by flash chromatography, obtaining fractions free of fatty acids and sugar derivatives (97:3 in HS and 95:5 in WS), and mixtures richer in phenolic compounds and flavonoids such as guaiacyl derivatives, quercetin, pinobanksin, and catechin. The most polar fractions presented a higher antioxidant capacity than that of the crude extracts.

Residues and dissipation kinetic of abamectin, chlorfenapyr and pyridaben acaricides in green beans (Phaseolus vulgaris L.) under field conditions using QuEChERS method and HPLC

The current study estimated the dissipation rates of abamectin, chlorfenapyr and pyridaben acaricides in pods of green beans (Phaseolus vulgaris L.) under field conditions in Egypt. Pesticides were extracted and cleaned-up by QuEChERS method and were analyzed by HPLC. The dissipation of these acaricides followed the first order kinetics model with half-life (t_1/2) values 1.00, 3.50 and 1.50 days for abamectin, chlorfenapyr and pyridaben, respectively. The lowest residues, at different time intervals of field application rate of each pesticide, were observed with abamectin followed by pyridaben and then chlorfenapyr. Pre-harvest intervals (PHIs) were 10.00, 13.50 and 6.00 days for abamectin, chlorfenapyr and pyridaben, respectively and were below the established European maximum residue limits (EU MRLs) 10-14, 14-21 and 7-10 days after application, respectively. If the fresh pods will be consumed after harvest, it is expected that the presence of these pesticides in the food will have a negative impact on human health. Therefore, the elimination of the residues of these harmful pesticides must be carried out.

[A brief history of the development of chromatography and its enlightenment to us]

This article describes the brief history of chromatography and clarifies a few confusions in some Chinese publications on the history of chromatography. Based on the analysis of several milestones in the development of chromatographic techniques, we summarized the enlightenment that the history tell us:(1) fundamental research has always been the source of advancements in science and technology, including chromatography; (2) the needs of social development have been the main driving force for the innovations in chromatographic methods; (3) interdisciplinary study has been an important approach to technological innovation; and (4) an unremitting persistence and courage to explore are the necessary conditions for technical innovation. Finally, the future development prospects of chromatography are also briefly discussed.

Chromatographic Analyses, In Vitro Biological Activities, and Cytotoxicity of Cannabis sativa L. Essential Oil: A Multidisciplinary Study

Due to renewed interest in the cultivation and production of Italian Cannabis sativa L., we proposed a multi-methodological approach to explore chemically and biologically both the essential oil and the aromatic water of this plant. We reported the chemical composition in terms of cannabinoid content, volatile component, phenolic and flavonoid pattern, and color characteristics. Then, we demonstrated the ethnopharmacological relevance of this plant cultivated in Italy as a source of antioxidant compounds toward a large panel of enzymes (pancreatic lipase, α-amylase, α-glucosidase, and cholinesterases) and selected clinically relevant, multidrug-sensible, and multidrug-resistant microbial strains (Staphylococcus aureus, Helicobacter pylori, Candida, and Malassezia spp.), evaluating the cytotoxic effects against normal and malignant cell lines. Preliminary in vivo cytotoxicity was also performed on Galleria mellonella larvae. The results corroborate the use of this natural product as a rich source of important biologically active molecules with particular emphasis on the role exerted by naringenin, one of the most important secondary metabolites.

The Dissipative Potential of Gamma Irradiation in Residues of Imidacloprid and Thiamethoxam in the Postharvest of Common Beans

Gamma irradiation (⁶⁰ Co) in postharvest of common beans (Phaseolus vulgaris L.), has already proven beneficial, regarding the prolongation of shelf life and physical, chemical, and organoleptic aspects of grains. However, few prior studies have investigated the effect of gamma irradiation on the dissipation of pesticides in foods, especially insecticides in beans. This study aimed to evaluate the waste dissipation of two insecticides, imidacloprid and thiamethoxam, used in the cultivation of common bean, a variety of Carioca, using gamma irradiation. Ground bean samples were spiked each insecticide in the laboratory at 3, 4, and 5 mg/kg, and were then irradiated at 0, 1, and 2 kGy per irradiator with a ⁶⁰ Co source. Liquid chromatography-tandem mass spectrometry was used to quantify the insecticides. The irradiation promoted dissipation of thiamethoxam at 1 and 2 kGy doses, with the highest dissipation verified at 2 kGy. In general, at this higher dose of irradiation the reduction dissipation of thiamethoxam was 66% of the mean value found in the treatment without irradiation and ∼44% relative to the 1 kGy dose. Conversely, imidacloprid showed no effect of irradiation on waste dissipation, except in the treatment of 5 mg/kg at 2 kGy dose. From the results, it was concluded that the gamma irradiation might have applicability in dissipating thiamethoxam in real bean samples.

PRACTICAL APPLICATION

Pesticide residues remaining from bean cultivation, sensitive to optimal doses of gamma irradiation, can be transformed into other less harmful or nonharmful substances, increasing the quality of the beans before the food arrives at the consumer's table. Irradiation of the grains after harvest also eliminates the need for application of other pesticides to preserve the grains during storage, as the technique is capable of eradicating deteriorating agents, such as microorganisms and insects.

[Tandem technologies in chromatographic analysis]

The acquisition of chemical compounds information from samples depends on the separation as well as detection techniques. Usually, it is difficult to achieve the separation and identification of all components in complex samples by a simple one-dimensional chromatographic method. Thus, tandem technologies, which mainly include column tandem connection techniques, detector tandem connection techniques, and multidimensional chromatography, have aroused widespread interest. In this paper, advances in the three aforementioned tandem techniques (not including chromatography tandem mass spectrometry) since 2010 are discussed. Typical applications for obtaining more comprehensive and accurate information from samples are also reviewed. Finally, the development of chromatographic tandem technologies is summarized and future prospects are examined.

Immunomodulatory Effects of Bifidobacterium longum W11 Produced Exopolysaccharide on Cytokine Production

BACKGROUND

Health benefits, including immune modulating capability, exerted by Bifidobacterium strains have been attributed to their exopolysaccharides (EPSs).

OBJECTIVE

The effects of the purified EPS from B. longum W11 on cytokine production by peripheral blood mononuclear cells (PBMCs) alone or ConA-stimulated were investigated.

METHOD

The production of IFN-γ, IL-1β, IL-6 and IL-10 by PBMCs from healthy adult donors was analysed using purified EPS at two different concentrations (100 µg/mL and 200 µg/mL) and ConA, as an immunopotentiating marker. Moreover, the monosaccharide composition of the EPS from B. longum W11 was detected using HPLC analysis.

RESULTS

The results demonstrated the ability of purified EPS to increase the production of the tested cytokines, except IL-10, in ConA-stimulated PBMCs. In not-stimulated-PBMCs, EPS increased the production of IL-6 (at 200 µg/mL) and IL-10 (at 100 µg/mL). The HPLC analysis showed the presence of main monomers, galactose and glucose (ratio 1:1 wt/wt), and small amount of rhamnose.

CONCLUSION

The results of this study demonstrate the ability of the EPS produced by B. longum W11 to interact in vitro with the human PBMCs, showing an immune-regulatory profile alone and an immune stimulatory profile in ConA-stimulated PBMCs. This suggests putative applications for the EPS from B. longum W11 in different pathological conditions.

Identification of Microbial Metabolites Elevating Vitamin Contents in Barley Seeds

The current investigation analyzes metabolites of Acetobacter aceti to explore chemical compounds responsible for the induction of vitamins in barley seeds. A bioactivity guided assay of bacterial extracts and chromatographic analyses of barley produce revealed 13 chemical compounds, which were subjected to principal component analysis (PCA). PCA determined four chemical compounds (i.e., quinolinic acid, pyridoxic acid, p-aminobenzoate, and α-oxobutanoic acid) highly associated with increased quantities of vitamins. Further experimentations confirmed that quinolinic acid and p-aminobenzoate were the most efficient vitamin inducers. The results indicated chloroform/ethanol (4:1) as the best solvent system for the extraction of active compounds from crude metabolites of A. aceti. Significant quantities of mevalonic acid were detected in the extracted fraction, indicating the possible induction of the isoprenoid pathway. Altogether, the current investigation broadens the frontiers in plant-microbe interaction.

Aflatoxins and ochratoxin A in pistachios sampled in Spain: occurrence and presence of mycotoxigenic fungi

A survey of the fungal contamination and occurrence of aflatoxins and ochratoxin A (OTA) in 50 pistachio nut samples collected from commercial stores around Catalonia (Spain) was carried out. Aspergillus flavus was found in 30% of samples, whereas Aspergillus section Nigri, Aspergillus ochraceus, and Penicillium verrucosum were found in 40%, 2% and 26% of samples, respectively. A total of 204 fungal isolates were obtained; 70.8% of A. flavus isolates were able to produce aflatoxin B1 and B2, whereas OTA production capacity was detected in 54.4% of the A. section Nigri biseriate isolates. Aflatoxins were detected in five samples (10% of total), all exceeding the maximum legal limit set for aflatoxin B1 (2 µg kg(-1)) or for total aflatoxins (4 µg kg(-1)), with one sample having a very high level of contamination (1134.5 µg kg(-1)). Only one sample of pistachio showed OTA contamination at 0.67 µg kg(-1). Simultaneous contamination by aflatoxins and OTA was not observed in these samples. It was concluded that the frequency of aflatoxins and OTA contamination in pistachio samples available in the Spanish market is relatively low. Thus, no significant contribution to health risk should be expected from aflatoxin consumption through pistachios among healthy consumers. However, the existence of single samples with an extremely high aflatoxin concentration reinforces the need for effective prevention strategies in pistachio processing and commercialization.

Surveys of rice sold in Canada for aflatoxins, ochratoxin A and fumonisins

Approximately 200 samples of rice (including white, brown, red, black, basmati and jasmine, as well as wild rice) from several different countries, including the United States, Canada, Pakistan, India and Thailand, were analysed for aflatoxins, ochratoxin A (OTA) and fumonisins by separate liquid chromatographic methods in two different years. The mean concentrations for aflatoxin B(1) (AFB(1)) were 0.19 and 0.17 ng g(-1) with respective positive incidences of 56% and 43% (≥ the limit of detection (LOD) of 0.002 ng g(-1)). Twenty-three samples analysed in the second year also contained aflatoxin B(2) (AFB(2)) at levels ≥LOD of 0.002 ng g(-1). The five most contaminated samples in each year contained 1.44-7.14 ng AFB(1) g(-1) (year 1) and 1.45-3.48 ng AFB(1) g(-1) (year 2); they were mostly basmati rice from India and Pakistan and black and red rice from Thailand. The average concentrations of ochratoxin A (OTA) were 0.05 and 0.005 ng g(-1) in year 1 and year 2, respectively; incidences of samples containing ≥LOD of 0.05 ng g(-1) were 43% and 1%, respectively, in the 2 years. All positive OTA results were confirmed by LC-MS/MS. For fumonisins, concentrations of fumonisin B(1) (FB(1)) averaged 4.5 ng g(-1) in 15 positive samples (≥0.7 ng g(-1)) from year 1 (n = 99); fumonisin B(2) (FB(2)) and fumonisin B(3) (FB(3)) were also present (≥1 ng g(-1)). In the second year there was only one positive sample (14 ng g(-1) FB(1)) out of 100 analysed. All positive FB(1) results were confirmed by LC-MS/MS.