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Climate change causes shifts in temperature patterns, and plants adapt their chemical content in order to survive. We compared the effect of low (LT) and high (HT) growing temperatures on the phytochemical content of broccoli (Brassica oleracea L. convar. botrytis (L.) Alef. var. cymosa Duch.) microgreens and the bioactivity of their extracts. Using different spectrophotometric, LC-MS/MS, GC-MS, and statistical methods, we found that LT increased the total phenolics and tannins in broccoli. The total glucosinolates were also increased by LT; however, they were decreased by HT. Soluble sugars, known osmoprotectants, were increased by both types of stress, considerably more by HT than LT, suggesting that HT causes a more intense osmotic imbalance. Both temperatures were detrimental for chlorophyll, with HT being more impactful than LT. HT increased hormone indole-3-acetic acid, implying an important role in broccoli's defense. Ferulic and sinapic acid showed a trade-off scheme: HT increased ferulic while LT increased sinapic acid. Both stresses decreased the potential of broccoli to act against H2O2 damage in mouse embryonal fibroblasts (MEF), human keratinocytes, and liver cancer cells. Among the tested cell types treated by H2O2, the most significant reduction in ROS (36.61%) was recorded in MEF cells treated with RT extracts. The potential of broccoli extracts to inhibit α-amylase increased following both temperature stresses; however, the inhibition of pancreatic lipase was increased by LT only. From the perspective of nutritional value, and based on the obtained results, we conclude that LT conditions result in more nutritious broccoli microgreens than HT. [ABSTRACT FROM AUTHOR]

Phytoplasmas are phytopathogenic bacteria that cause serious damage to agriculture. A quarantine pathogen, the flavescence dorée phytoplasma (FDp), often associated with grapevine yellows disease, affects viticultural production across Europe. However, the mechanisms of FDp pathogenicity are not still elucidated. In this study, symptomatic and asymptomatic grapevine (Vitis vinifera L. var. ‘Pinot gris’) leaves were sampled. Two different FDp genotypes (M38 and M54) were identified, and genotype-dependent changes to grapevine physiological responses through the development of FDp infection were analysed. Correlation analyses established a potential link between measured physiological parameters and relative FDp DNA abundance. Increased malondialdehyde levels pointed to the oxidative stress in infected leaves, and highly correlated with the activation of L-ascorbic acid synthesis. Levels of hydrogen peroxide were reduced in infected leaves, possibly as an FDp mechanism to avoid plant-derived oxidative damage. Genotype M54 was associated with a lower accumulation of soluble sugars and lower damage to photosynthetic pigments while retaining a higher titre than M38. Therefore, pronounced phytoplasma genotype-dependent changes in grapevine physiology, potentially caused by the differences between M54 and M38 on the level of the efficiency of their effectors should be further investigated. Altogether, results provide data on certain targets of FDp in grapevine and could assist in the identification of potential specific effectors of this phytoplasma to aid the efforts of FDp management in European vineyards. [ABSTRACT FROM AUTHOR]

Due to extreme climate changes, plants are exposed to severe soil water content, i.e. flooding and drought. The aim of this study was to assess the effect of different soil water content on the nutritional potential of young Chinese cabbage (Brassica rapa ssp. pekinensis) on the level of phenolics, sugars, photosynthetic pigments and antioxidant capacity. Total phenolic acids were induced in plants grown under drought conditions. Both types of stress increased soluble sugars in Chinese cabbage but reduced total tannins. Plants grown under drought had more L-ascorbic acid than the control group; however, the concentration of ferulic acid and quercetin was reduced. On the other hand, excess of water increased the amount of sinapic and ferulic acid, main hydroxycinnamic acids in Chinese cabbage. Photosynthetic pigments were more susceptible to flooding (reduced amount) than drought, the only exception was chlorophyll b whose concentration was significantly higher in plants grown under drought. In addition, among all the measured parameters, chlorophyll b reacted most specifically against flooding (decreased) and drought (increased). Chinese cabbage grown under flooding had reduced amount of porphyrins compared to the one grown under normal and drought conditions, but showed higher antioxidant capacity (ABTS). Based on the results, the use of excess water could be considered as a possibility when growing young Chinese cabbage since it increased the concentration of antioxidants sinapic and ferulic acid and resulted in higher antioxidant capacity, recorded by ABTS assay, compared to control plants. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new strategy for biofortification of cruciferous microgreens. • Production of caffeine-enriched cruciferous microgreens. • Membrane permeabilizers enhanced interspecific metabolite transfer. • Interspecific transfer of metabolites increased acceptor antioxidant capacity. • Inhibitory activity against enzymes related to diabetes and obesity improved. Interspecific metabolite transfer (ISMT) is a novel approach for plants biofortification. In this study, the effect of tea (Camellia sinensis; Cs), with or without membrane permeabilizers EDTA and Tween, as a donor plant on broccoli, cauliflower and kale sprouts was investigated. As a result, caffeine- and catechin-enriched broccoli, cauliflower and kale microgreens were produced. Kale sprouts were most permeable for catechins from Cs , while cauliflower was most permeable for caffeine. Cs + EDTA significantly increased vitamin C in broccoli and kale. Among the tested enzymes activity, pancreatic lipase was the most affected by the treatment with broccoli and cauliflower biofortified with Cs or Cs combined with permeabilizers. Broccoli sprouts biofortified with Cs most significantly inhibited α-amylase, while those biofortified with Cs combined with permeabilizers most significantly inhibited α-glucosidase. Results point to ISMT combined with membrane permeabilizers as a promising and eco-friendly biofortification strategy to improve the biopotential of Brassica microgreens. [ABSTRACT FROM AUTHOR]

Lettuce production in the winter on the Adriatic coast, especially in a non-heated plastic tunnel, requires longer cultivation and is characterised by lower head mass and yield. In these conditions, the effect of biostimulant Bio-algeen S-90 and fertilizer Megagreen on the production of the traditional winter lettuce cultivar 'Four Seasons' was tested. Both treatments showed a positive effect on the growth and total yield of winter lettuce, and decreased the share of non-marketable yield. Bio-algeen S-90 treatment increased the plant height by 61.5%, and foliar treatment with Megagreen by 60.9%, as compared to the control treatment. Equally, both treatments resulted in higher leaf numbers (47.7% for Bio-algeen S-90 and 37.2% for Megagreen). The head mass of lettuce treated with Bio-algeen S-90 and Megagreen was 30.3% and 25.0% higher than in the control treatment, respectively. Megagreen contributed more to chlorophyll and carotenoid content, while Bio-algeen S-90 elevated the amount of vitamin C and dry matter. The pH value of lettuce juice decreased after Bio-algeen S-90, while the mineral content (N, P and K) did not differ between the tested treatments. Lower nitrate content was detected after both treatments. The obtained results elucidate the effect of Bio-algeen S-90 and Megagreen on "low input" lettuce production. [ABSTRACT FROM AUTHOR]

SUMMARY Salicylic acid (SA) biosynthesis, the expression of SA-related genes and the effect of SA on the Arabidopsis- Plasmodiophora brassicae interaction were examined. Biochemical analyses revealed that, in P. brassicae-infected Arabidopsis, the majority of SA is synthesized from chorismate. Real-time monitored expression of a gene for isochorismate synthase was induced on infection. SA can be modified after accumulation, either by methylation, improving its mobility, or by glycosylation, as one possible reaction for inactivation. Quantitative reverse transcription-polymerase chain reaction (qPCR) confirmed the induction of an SA methyltransferase gene, whereas SA glucosyltransferase expression was not changed after infection. Col-0 wild-type (wt) did not provide a visible phenotypic resistance response, whereas the Arabidopsis mutant dnd1, which constitutively activates the immune system, showed reduced gall scores. As dnd1 showed control of the pathogen, exogenous SA was applied to Arabidopsis in order to test whether it could suppress clubroot. In wt, sid2 (SA biosynthesis), NahG (SA-deficient) and npr1 (SA signalling-impaired) mutants, SA treatment did not alter the gall score, but positively affected the shoot weight. This suggests that SA alone is not sufficient for Arabidopsis resistance against P. brassicae. Semi-quantitative PCR revealed that wt, cpr1, dnd1 and sid2 showed elevated PR-1 expression on P. brassicae and SA + P. brassicae inoculation at 2 and 3 weeks post-inoculation (wpi), whereas NahG and npr1 showed no expression. This work contributes to the understanding of SA involvement in the Arabidopsis- P. brassicae interaction. [ABSTRACT FROM AUTHOR]

Spectrophotometric and chromatographic analysis of phenolics in water and ethanolic extracts of wild asparagus, butcher's broom and black bryony from Croatia was conducted. Their antioxidant capacity (ABTS, DPPH and FRAP assay) and energy content were determined. The gastrointestinal stability of detected phenolics was determined using a two-phase in vitro digestion method with human enzymes. The highest phenolics yield, radical scavenging activity and ferric reducing antioxidant potential were recorded in 40 % ethanolic extract of black bryony, with glycosylated forms of kaempferol as dominant components. Quercetin-3- O-rutinoside and isorhamnetin-3- O-rutinoside were dominant phenolics in all wild asparagus extracts, and salicylic acid was predominant in butcher's broom 40 % ethanolic extract. Phenolic acids of the three species were not stable during gastric and duodenal phases of simulated digestion. Two main black bryony kaempferol glycosides were best preserved after digestion (50 % of each). Black bryony contains more energy than wild asparagus and butcher's broom. Accordingly, we propose black bryony as a valuable source of antioxidant kaempferol glycosides with relevant gastrointestinal stability and higher energy content than so far more conventional vegetable wild asparagus. [ABSTRACT FROM AUTHOR]

Auxin homeostasis is involved in many different plant developmental and stress responses. The auxin amino acid conjugate synthetases belonging to the GH3 family play major roles in the regulation of free indole-3-acetic acid (IAA) levels and the moss Physcomitrella patens has two GH3 genes in its genome. A role for IAA in several angiosperm – pathogen interactions was reported, however, in a moss – oomycete pathosystem it had not been published so far. Using GH3 double knockout lines we have investigated the role of auxin homeostasis during the infection of P. patens with the two oomycete species, Pythium debaryanum and Pythium irregulare . We show that infection with P. debaryanum caused stronger disease symptoms than with P. irregulare . Also, P. patens lines harboring fusion constructs of an auxin-inducible promoter from soybean (GmGH3) with a reporter (ß-glucuronidase) showed higher promoter induction after P. debaryanum infection than after P. irregulare , indicating a differential induction of the auxin response. Free IAA was induced upon P. debaryanum infection in wild type by 1.6-fold and in two GH3 double knockout (GH3-doKO) mutants by 4- to 5-fold. All GH3-doKO lines showed a reduced disease symptom progression compared to wild type. Since P. debaryanum can be inhibited in growth on medium containing IAA, these data might indicate that endogenous high auxin levels in P. patens GH3-doKO mutants lead to higher resistance against the oomycete. [ABSTRACT FROM AUTHOR]

Abstract: A procedure based on BIA Separations CIM DEAE anion-exchange chromatography was developed to separate double-stranded (ds) RNA of hypovirus infecting phytopathogenic fungus Cryphonectria parasitica. Using a linear gradient of 25mM 4-morpholinepropanesulfonic acid (MOPS), pH 7.0 as a binding buffer, and 25mM MOPS, 1.5M NaCl, 0.1mM EDTA, 15% isopropanol (v/v), pH 7.0 as an elution buffer, hypoviral dsRNA was additionally purified from nucleic acid species present in preparations partially purified by standard CF-11 cellulose chromatography. Moreover, crude phenol/chloroform extracts of the fungal tissue were also applied to monolithic supports and CIM DEAE chromatograms revealed clear evidence for hypoviral presence without CF-11 chromatography, nucleic acid precipitation, and electrophoresis. [Copyright &y& Elsevier]

Plants sense carbohydrates and transduce a signal which changes gene expression and the activities of many enzymes. The relationship between changes in gene expression by carbohydrates and the developmental state of the cells is still poorly understood. To gain more knowledge about this relationship, we have analyzed three sugar beet (Beta vulgaris L.) in vitro cell lines residing on distinct differentiation states. Cell suspensions were initiated and cells were incubated for 72h in the medium with sucrose as a control, or treated during the same period with glucose or 3-O-methylglucose (3OMG). Cellular and extracellular proteins, separated electrophoretically, showed that sugar-induced protein expression was cell line-specific. More differences were visible in extracellular and in glycoprotein than on cellular protein patterns. The 3OMG downregulated while glucose upregulated cellular glycoproteins. In the case of extracellular proteins, glucose and 3OMG were equally effective in both downregulation and upregulation of protein expression. Sialic acid was indicated as a glycan conjugate in sugar beet. Carbohydrate-induced gene expression was related to the developmental state of cells. [ABSTRACT FROM AUTHOR]

• First assessment on nutritional significance of interspecies phytochemical transfer. • Black bryony improved L -ascorbic acid, kaempferol and total phenolics in cabbage. • Black bryony improved antioxidant and hypoglycemic activity of cabbage. • St. John's-wort, rose and chamomille increased cabbage antiproliferative activity. • Transfer of L -ascorbic acid and phenolics is affected by donor matrix. The high demand for healthy food in recent years has led to an increasing need for highly bioactive plant materials. One such plant, Chinese cabbage, possesses flavonoids with antioxidant and antidiabetic properties, but they appear in low quantities. The interspecific transfer of metabolites is a promising technique that could contribute to the increase of the beneficial properties of food. The objective of the study was to determine how an interspecific source-sink phytochemical transfer from donor extracts to the Chinese cabbage affects its phenolic and vitamin C profile and intestinal bioaccessibility, hypoglycemic potential and antioxidant capacity. In addition, sprouts treated with Rosa sp. and Hypericum perforatum extracts showed better antiproliferative effect towards human breast adenocarcinoma cells than untreated sprouts. The results suggest that treatment of plants with donor extracts is a promising approach to improve the nutritional and phytochemical profile and bioactive properties of acceptor plants. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the phenolic profile, antiproliferative, and pro‐apoptotic activities of Asparagus acutifolius, Tamus communis, and Ruscus aculeatus aqueous extracts against human bladder (T24) and lung cancer (A549) cell lines. Antiproliferative activity of the extracts at the concentration range from 0.5 to 4 mg/ml was measured by MTT test, after the incubation period of 4, 24, 48, or 72 hr. Pro‐apoptotic activity of selected plant extracts against T24 and A549 cells was analyzed by flow cytometry at the concentrations of 0.5, 1, and 2 mg/ml. The highest antiproliferative activity against both cancer cell lines was detected by T. communis aqueous extract. The highest pro‐apoptotic effect was achieved by A. acutifolius aqueous extract and its effect was similar against A549 and T24 cells. Practical applications: Wild edible plants, such as wild asparagus, black bryony, and butcher's broom represent important aspect of the Mediterranean diet. They are rich source of various natural bioactive compounds which express different biological activities (antioxidative, antiproliferative, antibacterial, anti‐inflammatory...). The current trend for natural and healthy diet, such as the Mediterranean diet, is in relation to the rapidly growing problem of chronic diseases in a modern society. Wild edible plants have a high direct‐use value using them in dishes containing mixed vegetables, in soup preparation, as natural additives in fermented natural products containing cheese or fish, in water infusions (natural drinks). [ABSTRACT FROM AUTHOR]

The effects of a biodynamic sowing calendar on the growth (plant height, fresh herb yield, nodes number) and quality (percentage of leaf mass, essential oil content) of three basil species, Ocimum americanum L., Ocimum hybrida and Ocimum basilicum L., represented by the cultivars 'Rosso' and 'Eco Genovese', were tested. Statistical analyses showed that the species had greater impact on the observed parameters than either the sowing date or the species and sowing date in combination. The species showed a significant influence on all fi ve tested parameters, while sowing date and interaction of both factors significantly influenced plant height, leaf percentage and essential oil content. The best yield per plant was obtained for O. hybrida and O. basilicum 'Eco Genovese'. The lowest species O. hybrida produced the highest amount of essential oil. »Nodes number« parameter most clearly separated the species, but not the cultivars. Even though O. americanum gave the tallest plants, it did not yield either the highest amount of fresh herb or essential oil. This species' height was most consistent, considering the significant impact of biodynamic rhythm. Sowing date was not crucial for basil fresh yield; however if there is a need for taller plants with a higher percentage of leaf mass and more essential oil, sowing date needs to be controlled. [ABSTRACT FROM AUTHOR]

Quercetin is the main flavonoid in diet with a potential in the treatment of cancer, cardiovascular, and neurodegenerative diseases. Due to its specific planar chemical structure, quercetin readily forms chelates with metal ions. Complexes of bioactive compounds and metal ions such as lanthanum often show strong cytotoxic and antitumour properties. The aim of this study was to compare the genotoxic effects of the quercetin/lanthanum complex on human cervical carcinoma cells with compare it to the effects of free ligands, quercetin, and lanthanum alone. The quercetin/lanthanum complex showed considerable cytotoxicity in the concentration range of (100 to 1000) mmol mL-1 and exposure time of three hours. The complex also induced a dose-dependent pro-oxidative effects and the formation of single-strand and double-strand DNA breaks. Although we obtained promising results on the cell level, future experiments should answer whether the quercetin/lanthanum complex is cancer-specific and stable enough in physiological conditions to make a potential new antitumour drug. [ABSTRACT FROM AUTHOR]

Arctostaphylos uva-ursi (L.) Spreng. (bearberry) is a well-known traditional herbal plant used as a urinary tract disinfectant. Its antiseptic and diuretic properties can be attributed to hydroquinone, obtained by hydrolysis of arbutin. This study aimed to determine the toxic profile of free hydroquinone on urinary bladder cells (T24) as a target of therapeutic action. Quantitative and qualitative analysis of the extract and the digestive stability and bioavailability of arbutin and hydroquinone were performed by HPLC assay and simulated in vitro digestion, respectively. Cytotoxic effect, reactive oxygen species induction and proteome changes in T24 cells after hydroquinone treatment were determined using Neutral red assay, 2′,7′-dichlorofluorescein-diacetate (DCFH-DA) assay and mass spectrometry, respectively. Through in vitro digestion, arbutin was stable, but hydroquinone increased after pepsin treatment (109.6%) and then decreased after the small intestine phase (65.38%). The recommended doses of Uva-ursi had a cytotoxic effect on T24 cells only when all hydroquinone conjugates were converted to free hydroquinone (320 and 900 μg/mL) and the toxic effect was enhanced by recovery. One cup of the therapeutic dose had a prooxidative effect after 4 h of incubation. Shorter time of cell exposure (2 h) to hydroquinone did not have any impact on reactive oxygen species induction. Proteomic analysis found 17 significantly up-regulated proteins compared to control. Hydroquinone activated proteins related to oxidative stress response, stress-adaptive signalling, heat shock response and initiation of translation. Despite the therapeutic properties of bearberry, up-regulated T24 cell proteins are evidence that plant compounds, although from a natural source, may exhibit negative properties. [Display omitted] • During digestion, arbutin was stable; HQ content decreased in the intestine. • Uva-ursi had a cytotoxic effect on T24 cells only when all arbutin content was converted to HQ. • The toxic effect of HQ is enhanced after recovery. • The therapeutic dose of Uva-ursi had a prooxidative effect in bladder cells. • HQ up-regulated 17 proteins in T24 cells related to stress response and cell viability. [ABSTRACT FROM AUTHOR]

The obligate biotrophic pathogen Plasmodiophora brassicae causes clubroot disease in Arabidopsis thaliana, which is characterized by large root galls. Salicylic acid ( SA) production is a defence response in plants, and its methyl ester is involved in systemic signalling. Plasmodiophora brassicae seems to suppress plant defence reactions, but information on how this is achieved is scarce. Here, we profile the changes in SA metabolism during Arabidopsis clubroot disease. The accumulation of SA and the emission of methylated SA (methyl salicylate, MeSA) were observed in P. brassicae-infected Arabidopsis 28 days after inoculation. There is evidence that MeSA is transported from infected roots to the upper plant. Analysis of the mutant Atbsmt1, deficient in the methylation of SA, indicated that the Arabidopsis SA methyltransferase was not responsible for alterations in clubroot symptoms. We found that P. brassicae possesses a methyltransferase ( PbBSMT) with homology to plant methyltransferases. The PbBSMT gene is maximally transcribed when SA production is highest. By heterologous expression and enzymatic analyses, we showed that PbBSMT can methylate SA, benzoic and anthranilic acids. [ABSTRACT FROM AUTHOR]