Chlorogenic Acid Content Research Articles

Enzyme inhibitory and antioxidant activities and HPLC quantification of chlorogenic acid in Helichrysum stoechas (L.) Moench and H. stoechas subsp. barrelieri (Ten) Nyman

The inhibitory effects of ethanol (80%) and aqueous extracts of Helichrysum stoechas (L.) Moench and H. stoechas subsp. barrelieri (Ten) Nyman on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), two sister enzymes associated with pathogenesis of Alzheimer's disease (AD), as well as on elastase and collagenase, linked to inflammation and skin aging, were investigated. Simultaneously, antioxidant activity of the extracts was assessed through DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP), and metal-chelating activity assays, since oxidative damage plays a critical role in both AD pathophysiology and skin aging. Total phenol and flavonoid contents in the extracts were spectrophotometrically determined. The highest AChE inhibitory activity (44.60 ± 4.4% at 2000 µg/mL) was found in the ethanol extract of H. stoechas subsp. barrelieri collected from Hatay, and the uppermost BChE inhibitory activity at same concentration was found in the aqueous extract of H. stoechas subsp. barrelieri collected from Izmir (80.24 ± 2.63%, IC50: 38.52 ± 1.41 µg/mL). Both of them inhibited AChE and BChE in a concentration-dependent manner. Nevertheless, none of the extracts from the two plants inhibited the elastase and collagenase. Although both ethanolic and aqueous extracts had significant antioxidant activity in DPPH radical scavenging and FRAP assays, they demonstrated inadequate antioxidant activity in metal-chelating assay. Chlorogenic acid was quantified in the extracts using HPLC. The mentioned two extracts having strong cholinesterase (ChE) inhibition had also the highest chlorogenic acid content. The ethanol extract of H. stoechas (Hatay sample) and the aqueous extract of H. stoechas (Izmir sample) seem to contain promising ChE inhibitors, which deserve further investigation.

Response Surface Methodology as a Tool for Optimization of Extraction Process of Bioactive Compounds from Spent Coffee Grounds

The main goal of this research was to model and optimize the extraction process of bioactive compounds from spent coffee grounds (SCG). This study utilized response surface methodology (RSM) to determine the significance of the effects of independently tested extraction process conditions and their interactions. The quality of the SCG extracts was evaluated by performing the following determinations: total polyphenols content (TPC), ABTS and FRAP assays, browning index (BI), and caffeine and chlorogenic acids contents by high-performance liquid chromatography. The resultant optimal extraction conditions, which maximized recovery of antioxidant bioactive compounds, were 65% hydroethanolic solution (v/v) in a solvent–matrix ratio of 51 mL/g CS, followed by ultrasound-assisted extraction carried out for 30 min at 60 °C. The SCG extract obtained by this extraction variant had values for TPC, ABTS, FRAP and BI of approximately 38 mg GAE (gallic acid equivalent) per g d.m. SCG, 73 mg Trolox/g d.m. SCG, 81 µmol Fe (II)/g d.m. SCG, and 0.22, respectively. The sample was also characterized by a high content of caffeine (5 mg/g d.m. SCG) and chlorogenic acids (8 mg/g d.m. SCG). Based on the obtained results, SCG may be recognized as a coffee by-product that has abundant components with antioxidant activity and broad possible applications in agri-food processing fields.

Petals of different ornamental rose cultivars as a rich source of bioactive compounds for functional foods

The aim of this study was to investigate the profile of bioactive compounds in petals of 23 cultivars of garden roses. We found that flowers are a rich source of phenols, flavonoids, and anthocyanins, especially the cultivars with red petals. Chlorogenic acid content did not depend on the flower color. White cultivars as well as those with pale colors had highest level of hydroxychloroquine. Petals of all cultivars showed high content of vitamin C and low of vitamins B. Glutathione was detected at high levels in the majority of examined roses. Total antioxidant capacity was found to be very high and depended on the cultivar. For the first time the presence of hydroxychloroquine was detected in plant material. Soluble oxalates content was very low. High levels of phytochemicals in the rose flowers make them excellent candidates for the food and nutraceutical industry. Some cultivars i.e. 'Chorus', 'Abraham Darby', 'Graham Thomas', 'Mary Rose', 'Morning Jewel', 'Moje Hammarberg' are particularly rich sources of valuable bioactive ingredients such as phenols, flavonoids, anthocyanins and vitamin C.

Technological and sensory properties of plant-based meat analogues containing fermented sunflower protein concentrate

Sunflower press cake is a protein-rich sidestream from oil production, that is potentially suitable for human consumption, but its utilisation is hindered by the high content of chlorogenic acid (CGA), an abundant anti-nutritional factor. Here we show that processing sunflower protein concentrate (SP) by fermentation (fSP) reduces the CGA content while increasing the level of free amino acids, but impairs the formation of fibrillar structures and generates a sour taste. After fermentation of SP pH was shifted to neutral (fSP7). Meat analogues based on SP, fSP, fSP7, and pea protein isolate were prepared by high-moisture extrusion processing, which reduced CGA levels further. The texture and colour of the extrudates were both improved by the neutral pH shift. Finally, the odour, flavour and structure were assessed by a trained sensory panel. We found that fermentation followed by a neutral pH shift encouraged the formation of fibrillar structures and prevented sour taste attributes in the meat analogue. Our data will facilitate the development of sunflower protein products that are more palatable and nutritionally beneficial for humans.

Integrated Transcriptomic and Metabolomic Analyses Reveal the Effects of Grafting on Special Metabolites of Acanthopanax senticosus Leaves.

Acanthopanax senticosus (A. senticosus) is a member of Acanthopanax Miq. and is used in traditional Chinese medicine, and it has been found that grafting technology can be used to alter plant metabolite composition and transcriptome characteristics. In this study, shoots of A. senticosus were grafted onto the rootstocks of the vigorous Acanthopanax sessiliflorus (A. sessiliflorus) to improve its varietal characteristics. In order to investigate the changes in metabolites and transcriptional patterns in grafted A. senticosus leaves (GSCL), fresh leaves were collected from 2-year-old grafted A. senticosus scions, while self-rooted seedling A. senticosus leaves (SCL) were used as controls to analyse the transcriptome and metabolome. Metabolic profiles and gene expression patterns were further identified and correlated in special metabolite target pathways. The content of chlorogenic acid and triterpenoids in the GSCL was higher than in the control, while the quercetin content was lower. All these metabolic changes were associated with changes in the expression pattern of transcripts. Our results revealed the transcriptome and metabolome characteristics of GSCL. This may help to improve leaf quality in A. senticosus cultivation, suggesting that it is feasible to improve the medicinal quality of GSCL through asexual propagation, but the long-term effects need further investigation. In conclusion, this dataset provides a useful resource for future studies on the effects of grafting on medicinal plants.

Polyphenols Profile and Antioxidant Activity Characterization of Commercial North Italian Ciders in Relation to Their Geographical Area of Production and Cidermaking Procedures

Twenty-four samples of differently produced commercial Italian cider were analyzed for their polyphenols profile and antioxidant activity. A partial least square regression was used to correlate the ciders’ antioxidant activity with their polyphenolic content. Statistical analyses revealed only a clustering pattern in the samples based on their geographical area of production (North-West, NW, vs. North-East, NE). Indeed, NW ciders, compared to NE ones, showed higher antioxidant activity and higher contents of procyanidin B1, catechin, chlorogenic acid, epicatechin, and total polyphenols. On the contrary, no clear-cut clustering pattern determined by cidermaking procedures (i.e., Charmat or Champenoise method) has been observed. These data suggest that the differences observed between NW and NE ciders might be accounted uniquely to the use of different apple varieties and/or the maturation status, as well as the pedoclimatic conditions of their production areas and not for cellar procedures’ specificity.

Chemical and Biological Characterization of Green and Processed Coffee Beans from Coffea arabica Varieties.

Coffee is one of the most consumed beverages in the world; its production is based mainly on varieties of the Coffea arabica species. Mexico stands out for its specialty and organic coffee. In Guerrero, the production is done by small indigenous community cooperatives that market their product as raw material. Official Mexico Standards stipulate the requirements for its commercialization within the national territory. In this work, the physical, chemical, and biological characterizations of green, medium, and dark roasted beans from C. arabica varieties were carried out. Analysis by HPLC showed higher chlorogenic acid (55 mg/g) and caffeine (1.8 mg/g) contents in the green beans of the Bourbon and Oro Azteca varieties. The caffeine (3.88 mg/g) and melanoidin (97 and 29 mg/g) contents increased according to the level of roasting; a dissimilar effect was found in the chlorogenic acid content (14.5 mg/g). The adequate nutritional content and the sensory evaluation allowed the classification of dark-roasted coffee as premium coffee (84.25 points) and medium-roasted coffee as specialty coffee (86.25 points). The roasted coffees presented antioxidant activity without cytotoxic effects; the presence of CGA and caffeine supports the beneficial effects of drinking coffee. The results obtained will serve as a basis for making decisions on improvements to the coffees analyzed.

Impact of Processing Method and Storage Time on Phytochemical Concentrations in an Antioxidant-Rich Food Mixture.

Foods high in phytochemicals are known for their role in the prevention of chronic disease development, but after processing and storage, such food products may lose part of their functionality as these compounds are sensitive to the impact of processing temperature and the type of methods applied. Therefore, we measured the levels of vitamin C, anthocyanins, carotenoids, catechins, chlorogenic acid, and sulforaphane in a complex blend of fruits and vegetables, and when applied to a dry food product, after exposure to different processing methods. These levels were compared between pasteurized, pascalized (high-pressure processing), and untreated conditions. Furthermore, we established the effect of freezing and storage time on the stability of these compounds. The results showed that pascalization better preserved vitamin C and sulforaphane, whereas pasteurization resulted in higher concentrations of chlorogenic acid, carotenoids, and catechins. For samples which were frozen and thawed immediately after processing, pascalization was the optimal treatment for higher contents of lutein, cyanidin-3-glucoside, quercetin-3-glucoside, delphinidin-3-glucoside, peonidin-3-glucoside, and epicatechin gallate. Ultimately, the optimal processing method to preserve phytochemicals in fruit and vegetable products is as complex as the blend of compounds, and this decision-making would best be led by the prioritized nutrient aim of an antioxidant food product.

Effect of antioxidant and anti-inflammatory on bioactive components of carrot (Daucus carota L.) leaves from Jeju Island

The present study evaluated the potential of carrot (Daucus carota L.) leaf, a non-edible part of carrots, which are among the most consumed vegetables worldwide. The antioxidant activities of 70% ethanol extract (EEC) and hot water extract (HEC) of carrot leaves were compared. The results revealed that the total polyphenol content, total flavonoid content, and DPPH and ABTS radical scavenging activities were higher in EEC than in HEC. Both extracts protected the cells against H2O2-induced toxicity and markedly reduced the levels of reactive oxygen species in RAW 264.7 cells. Moreover, pretreatment of RAW 264.7 cells with EEC and HEC prior to H2O2 (500 μM) exposure increased superoxide dismutase and glutathione peroxidase activities in these cells. Notably, EEC and HEC increased intracellular catalase activity by 36.77 and 6.39 times, respectively. Compared to HEC, EEC remarkably inhibited the production of lipopolysaccharide-induced nitric oxide and reduced the gene expression of IL-6, IL-1β, iNOS, COX-2, and TNF-α. Comparative analysis of the composition of the extracts using HPLC–UV suggested notably higher contents of catechin, chlorogenic acid, caffeic acid, rutin, quercetin, and cynaroside in EEC than in HEC. Collectively, these results imply that carrot leaves are a potentially beneficial natural source of antioxidants and anti-inflammatory compounds in functional foods.

Biological and phytochemical potential of Baccharis trimera (Less.) DC leaf extract on swine clinical isolates

Phytochemical studies have shown extracts obtained from the aerial parts of Baccharis trimera (Less.) DC has antioxidant and antimicrobial activities and the potential to treat some diseases. This study investigated the phenolic compounds, antioxidant and antimicrobial activity, and phytochemical potential of B. trimera leaf extract obtained by decoction on ATCC standard bacterial strains and 23 swine clinical isolates. Water was used as an extraction solvent based on the principles of green chemistry and at a low cost. The decoction process resulted in an extract rich in phenolic compounds and a high capacity for scavenging DPPH and ABTS radicals. Phytochemical analysis of aqueous extracts was performed using HPLC-DAD, and high concentrations of chlorogenic, ferulic, caffeic, and cinnamic phenolic acids were found. Antimicrobial activity was observed against gram-negative bacteria. B. trimera aqueous extract may be a promising low-cost agent for prophylactic treatment against swine enteropathogens and contribute to reducing production costs.

The effect of several postharvest processing on the quality of Robusta Coffee (Coffea canephora)

Postharvest processing, especially in picking, is an essential factor affecting the quality of Robusta coffee (Coffea canephora). This study was aimed to compare the effect of Postharvest processing on the quality of Robusta coffee. The Postharvest methods used in this research were the farmer’s metods, natural process, semi-wet, and wet methods. The observed parameters in this study were physical quality, caffeine content and chlorogenic acid content. The results showed that the physical quality of the farmer’s process, the dirt content exceeded 0.5%, had black seeds, cracked black, cocoa beans, cracked seeds, and hollow seeds which were higher than SNI (Indonesian National Standard) with quality number four based on the defect value. While the quality of the natural, semi-wet and wet methods was in accordance with SNI with quality number two. The results of further testing for the farmer method obtained caffeine content of 1.80% and chlorogenic acid content of 1.00%, natural method of 1.79 % caffeine and chlorogenic acid of 1.32%, the semi-wet method caffeine of 1.92% and chlorogenic acid of 1.28 %, wet method of the caffeine of 1.83% and chlorogenic acid of 1.25%. This shows that the processing with the lowest quality is shown in the processing method of farmers.

Composition of Proteins and Phenolics in the Leaves of Different Mulberry Species (Morus alba L., M. alba × rubra, M. australis Poir., M. nigra L.)

The leaves of the mulberry (Morus sp.) have a variety of medicinal, culinary, industrial and agricultural applications. In our study, we compared the protein and phenolic contents of different mulberry species (Morus alba L., M. alba × rubra, M. australis Poir., M. nigra L.) from the mulberry germplasm collection to determine species-specific differences. The possibility of using mulberries as animal feed and for pharmacological purposes was reviewed. Total phenols of all genotypes were analysed using the Folin-Ciocalteu method, while total protein content was determined using the Lowry's method. The individual phenols were analysed by high-performance liquid chromatography with UV/VIS detection. The total protein content ranged from 162.03 mg BSA/g DW (M. australis) to 239.42 mg BSA/g DW (M. alba). Significantly higher contents of total proteins were determined in the leaves of M. alba. The highest mean concentrations of total phenols (21.51 mg GAE /g DW), chlorogenic acid (18.05 mg/g DW), 4-caffeoylquinic acid (4.36 mg/g DW), 5-p-coumaroylquinic acid (2.01 mg/g DW), quercetin glycoside (0.74 mg/g DW) and kaempferol acetyl hexoside (4.42 mg/g DW) were determined in M. alba × rubra and M. nigra. In contrast, white mulberry (M.alba) genotypes contained on average the most rutin (2.63 mg/g DW) and quercetin-malonyl-hexoside (1.59 mg/g DW). It can be concluded that the leaves of the white mulberry are best suited as animal feed due to their high protein content, while the black mulberry and the hybrid M. alba × rubra have pharmacological potential due to their high phenolic content.

Evaluation of co-fermentation of L. plantarum and P. kluyveri of a plant-based fermented beverage: Physicochemical, functional, and sensory properties

In this study, Pichia kluyveri (P. kluyveri) and Lactobacillus plantarum (L. plantarum) were sequentially inoculated into a plant-based beverage consisting of bananas, broccoli, and wolfberries. The physicochemical characteristics, functional components, and taste of it at different stages were determined. After 8-d fermentation, the viable counts of P. kluyveri and L. plantarum were 6.50 log CFU/mL and 8.43 log CFU/mL, respectively. The ethanol was <0.5 % (v/v). Compared with control group, the superoxide dismutase (SOD) activity increased by 96.08 folds and total phenolics content increased by 1.09 folds. The contents of lactic acid, protocatechuic acid, and chlorogenic acid exhibited an upgrade trend, whereas the contents of caffeic acid and malic acid presented a downward tendency. Some organic acids had positive correlations with sensory quality, especially sourness. In addition, the γ-amino butyric acid (GABA) concentration and antioxidant activity were also improved during fermentation. Results showed the nutritional functional properties and sensory quality of this beverage could be improved through co-fermentation of P. kluyveri and L. plantarum.

Comparison of different pretreatments on drying characteristics, physical properties, nutritional compounds and antioxidant activity of heat pump‐dried longan pulp

SummaryDrying pretreatments are usually considered as effective way to improve the quality of dried fruit products. The results of this research showed that the blanching (BL), ultrasonic (US) and freeze–thaw (FT) pretreatments could significantly shorten the drying time, and improve the rehydration capacity of the dried longan pulp. Compared with the control group (CK, without pretreatment), more irregular inner micropores were formed in the dried longan pulp treated with BL, US and FT. Besides, the brightness and yellowness of dried longan pulp with pretreatments were higher than those of the CK. The higher retention rates of total phenolic content (292.54 mg/100 g d.b.) and ascorbic acid (2.38 mg g−1 d.b.) were observed in the dried longan pulp treated with BL. Meanwhile, a higher chlorogenic acid content was found in the samples treated with FT (3.68 mg/100 g d.b.) and radio frequency (RF) (3.10 mg/100 g d.b.). Furthermore, the highest retention of a total free amino acid (1843.13 mg/100 g d.b) was exhibited by RF‐treated longan pulp. This work guides how pretreatments are applied prior to longan pulp drying.

Influence of Plant Growth Retardants and Nitrogen Doses on the Content of Plant Secondary Metabolites in Wheat, the Presence of Pests, and Soil Quality Parameters

Wheat is the cereal most susceptible to lodging, particularly during the flowering period and at the early ripening stage. The use of plant growth retardants (PGRs) is especially recommended when intensive nitrogen (N) fertilisation is applied, which increases the susceptibility of plants to lodging. This paper presents the results of tests into the effects of PGRs (PGR0—control; PGR1—chlormequat chloride (CCC) + trinexapac-ethyl (TE); PGR2—chlormequat chloride (CCC) + ethephon (ET)), and N dose—N0, N20, N40, and N60 [0, 20, 40, and 60 kg N ha−1] on the content of selected plant secondary metabolites (PSM) in the Indian dwarf wheat (Triticum sphaerococcum Percival) of the Trispa cultivar, and on the abundance of insect pests. In the developmental stage of wheat (BBCH 39), insects were collected with an entomological net. The study also investigated the effect of experimental factors on the physicobiochemical properties of the soil (pH in KC, granulometric composition, total organic carbon TOC, total nitrogen TN, fractional composition of humus, and the activity of enzymes). An increase in the plant secondary metabolite (PSM) and FRAP (ferring reducing ability of plasma) contents following the application of PGRs and N fertilisation already from as low a rate as 20 kg ha−1 was demonstrated. A significant positive correlation was noted between the abundance of Oulema spp. and the contents of total polyphenols, chlorogenic acid, and FRAP. No such relationship was noted for Aphididae or Thysanoptera. TOC content was higher on the plots on which N fertilisation was applied at the highest rate and after the application of PGRs. The factor determining the TN content was N fertilisation. Soil samples of the PGR0 N0 treatment were characterised by the greatest proportion of carbon in the humic and fulvic acid fractions and by the smallest proportion of carbon in the humin fraction. N fertilisation increased the proportion of carbon in the humin fraction on the plots on which no PGRs were applied. The study demonstrated an increase in the activity of oxidoreductive enzymes following the application of higher N rates. The application of PGRs resulted in no inhibition of enzymes in the soil compared to the control (PGRs0).

High-resolution genome mapping and functional dissection of chlorogenic acid production in Lonicera maackii.

Amur honeysuckle (Lonicera maackii) is a widely used medicinal plant of the Caprifoliaceae family that produces chlorogenic acid. Research on this plant mainly focuses on its ornamental value and medicinal compounds, but a reference genome sequence and molecular resources for accelerated breeding are currently lacking. Herein, Nanopore sequencing and high-throughput chromosome conformation capture (Hi-C) allowed a chromosome-level genome assembly of Lonicera maackii (2n = 18). A global view of the gene regulatory network involved in the biosynthesis of chlorogenic acid and the dynamics of fruit coloration in L. maackii was established through metabolite profiling and transcriptome analyses. Moreover, we identified the genes encoding hydroxycinnamoyl-CoA quinate transferase (LmHQT) and hydroxycinnamoyl-CoA shikimic/quinate transferase (LmHCT), which localized to the cytosol and nucleus. Heterologous overexpression of these genes in Nicotiana benthamiana leaves resulted in elevated chlorogenic acid contents. Importantly, HPLC analyses revealed that LmHCT and LmHQTs recombinant proteins modulate the accumulation of chlorogenic acid (CGA) using quinic acid and caffeoyl CoA as substrates, highlighting the importance of LmHQT and LmHCT in chlorogenic acid biosynthesis. These results confirmed that LmHQTs and LmHCT catalyze the biosynthesis of CGA in vitro. The genomic data presented in this study will offer a valuable resource for the elucidation of CGA biosynthesis and facilitating selective molecular breeding.

Integrated Transcriptome and Metabolome Analysis Reveal That Exogenous Gibberellin Application Regulates Lignin Synthesis in Ramie

Gibberellin regulates plant growth, development, and metabolic processes. However, the underlying mechanism of the substantial effect of gibberellin on stem height and secondary metabolites in forage ramie is unclear. Therefore, this study combined transcriptomic and metabolomics analyses to identify the mechanisms regulating growth and secondary metabolite contents in forage ramie following exogenous gibberellin application. Exogenous gibberellin application significantly reduced the lignin content in the leaves but not in the stems. At the same time, gibberellin significantly increased the total flavonoid and chlorogenic acid contents in both the stems and leaves. In addition, 293 differentially expressed genes (DEGs) and 68 differentially expressed metabolites (DEMs) were identified in the leaves. In the stems, 128 DEGs and 41 DEMs were identified. The DEGs PER42, FLS, CYP75A, and PNC1 were up-regulated in the leaves, affecting phenylpropane metabolism. The joint analysis of the DEMs and DEGs revealed that the changes in the DEGs and DEMs in the leaves and stems improved the substrate efficiency in the phenol propane pathway and inhibited lignin synthesis in plants, thus shifting to flavonoid pathway synthesis. In conclusion, gibberellin treatment effectively reduces the lignin content in forage ramie while increasing the flavonoid and chlorogenic acid contents. These findings provide empirical and practical guidance for breeding for forage quality in ramie and the improvement and cultivation control of forage ramie.

Effects of tomato inoculation with the entomopathogenic fungus Metarhizium brunneum on spider mite resistance and the rhizosphere microbial community.

Entomopathogenic fungi have been well exploited as biocontrol agents that can kill insects through direct contact. However, recent research has shown that they can also play an important role as plant endophytes, stimulating plant growth, and indirectly suppressing pest populations. In this study, we examined the indirect, plant-mediated, effects of a strain of entomopathogenic fungus, Metarhizium brunneum on plant growth and population growth of two-spotted spider mites (Tetranychus urticae) in tomato, using different inoculation methods (seed treatment, soil drenching and a combination of both). Furthermore, we investigated changes in tomato leaf metabolites (sugars and phenolics), and rhizosphere microbial communities in response to M. brunneum inoculation and spider mite feeding. A significant reduction in spider mite population growth was observed in response to M. brunneum inoculation. The reduction was strongest when the inoculum was supplied both as seed treatment and soil drench. This combination treatment also yielded the highest shoot and root biomass in both spider mite-infested and non-infested plants, while spider mite infestation increased shoot but reduced root biomass. Fungal treatments did not consistently affect leaf chlorogenic acid and rutin concentrations, but M. brunneum inoculation via a combination of seed treatment and soil drenching reinforced chlorogenic acid (CGA) induction in response to spider mites and under these conditions the strongest spider mite resistance was observed. However, it is unclear whether the M. brunneum-induced increase in CGA contributed to the observed spider mite resistance, as no general association between CGA levels and spider mite resistance was observed. Spider mite infestation resulted in up to two-fold increase in leaf sucrose concentrations and a three to five-fold increase in glucose and fructose concentrations, but these concentrations were not affected by fungal inoculation. Metarhizium, especially when applied as soil drench, impacted the fungal community composition but not the bacterial community composition which was only affected by the presence of spider mites. Our results suggest that in addition to directly killing spider mites, M. brunneum can indirectly suppress spider mite populations on tomato, although the underlying mechanism has not yet been resolved, and can also affect the composition of the soil microbial community.

Elicitation and Enhancement of Phenolics Synthesis with Zinc Oxide Nanoparticles and LED Light in Lilium candidum L. Cultures In Vitro

In this study, we identified and determined the content of phenolic compounds in Lilium candidum adventitious bulbs formed in vitro. HPLC analysis revealed the presence of four phenolic acids: chlorogenic, caffeic, p-coumaric, and ferulic acid. Phenolic acid content was assessed in adventitious bulbs formed in vitro on media supplemented with zinc oxide nanoparticles (ZnO NPs at 25, 50, and 75 mg/L) under fluorescent light (FL) or in darkness (D). The second experiment analyzed the effects of light-emitting diodes (LEDs) of variable light spectra on the formation of adventitious bulbs and their contents of phenolic acids. Spectral compositions of red (R; 100%), blue (B; 100%), red and blue (RB; 70% and 30%, respectively), a mix of RB and green (RBG) in equal proportions (50%), and white light (WLED, 33.3% warm, neutral, and cool light, proportionately) were used in the study. FL and D conditions were used as controls for light spectra. Bulbs grown in soil served as control samples. The most abundant phenolic acid was p-coumaric acid. Treatment with LED light spectra, i.e., RB, RBG, WLED, and B, translated into the highest p-coumaric acid concentration as compared with other treatments. Moreover, all the bulbs formed in light, including those grown on the media supplemented with ZnO NPs and under FL light, contained more p-coumaric acid than the bulbscales of the control bulbs grown in soil. On the other hand, control bulbs grown in soil accumulated about two to three times higher amounts of chlorogenic acid than those formed in vitro. We also found that the levels of all examined phenolics decreased under FL, R, and D conditions, while the bulblets formed in vitro under RB light showed the highest phenolic content. The use of ZnO NPs increased the content of p-coumaric, chlorogenic, and caffeic acid in the bulblets formed under FL as compared with those grown in darkness.

Wheat craft beer made from AFB1-contaminated wheat malt contains detectable mycotoxins, retains quality attributes, but differs in some fermentation metabolites

Levels of aflatoxin B1 (AFB1) were measured during the production of wheat craft beer made with wheat malt contaminated with AFB1 (1.23 µg/kg). A wheat craft beer made with non-contaminated wheat malt was produced for comparison purposes. AFB1 was measured after mashing (malt after the mashing process), and in spent grain (spent grains are filtered to collect the wort - remaining sugar-rich liquid), sweet wort, green beer, spent yeast, and in beer. Physicochemical parameters (pH, titratable acidity, color parameters, total soluble solids), sugars, organic acids, alcohols, and phenolics were evaluated after mashing, and in sweet wort, green beer, and beer samples. Density and yeast counts were determined over 120 h of sweet wort fermentation every 24 h. The AFB1 levels in the final beer were 0.22 µg/L, while the spent grains and spent yeasts contained 0.71 ± 0.17 and 0.11 ± 0.03 µg/kg of AFB1, respectively. AFB1 contamination did not influence the final product's physicochemical parameters, density during fermentation, fructose, or glycerol content. Higher yeast counts were observed during the first 48 h of non-contaminated wheat craft beer fermentation, with higher ethanol, citric acid, and propionic acid contents and lower glucose, malic acid, and lactic acid contents compared with beer contaminated with AFB1. Non-contaminated wheat craft beer also had higher concentrations of gallic acid, chlorogenic acid, catechin, procyanidin A2, and procyanidin B1. AFB1 contamination of wheat malt may not affect basic quality parameters in wheat craft beer but can influence the final product's organic acid and phenolic contents. Our findings show that if wheat craft beer is made with contaminated malt, AFB1 can remain in the final product and may pose a risk to consumers.