Plant Extracts as Antimicrobial Agents in Sustainable Conservation of Erythrina caffra (Fabaceae) Historical Trees.

Microbial colonization plays a relevant role in the biodegradation and biodeterioration of cultural and natural heritage, representing a revealing problem in conservation strategy. In this study, the essential oil (EO) and hydro-alcoholic extract (HAE) of Origanum vulgare L. (Lamiaceae), an aromatic perennial plant, representative of the Mediterranean basin, growing spontaneously and cultivated all over the world, were analysed. Natural products, such as essential oil and hydro-alcoholic extract, have strong antiseptic and antimicrobial properties and are ad hoc applied for the sustainable conservation of Erithryna caffra (Fabaceae). The main taxa revealed in the damaging of these arboreal heritage, are Bacillus sp., Streptomyces sp. and Terribacillus sp. (as bacteria), Alternaria sp., Aspergillus sp. and Chaetomium sp. (as fungi). GS-MS analysis identified carvacrol, thymol and their biosynthetic precursors γ-terpinene and p-cymene, as main components, and the antimicrobial efficiency assayed by in vitro methods (Agar Dish Diffusion, Well Plate Diffusion). In this study, by combining the application/exposure of both HAE and EO, the bacterial and fungal colonies development has been in vitro countered. The results confirm the possible use of plant products as a valid alternative to the traditional synthetic chemical biocides, with full respect to the environment.

Biological Investigation and Chemical Study of Brassica villosa subsp. drepanensis (Brassicaeae) Leaves.

Brassica villosa subsp. drepanensis (Caruel) Raimondo & Mazzola, belonging to the Brassica oleracea complex, is a wild edible plant endemic to western Sicily and a relative of modern cultivated Brassica crops. In this study, the antioxidant properties, anti-inflammatory activities, enzymatic inhibition, and cytotoxicity in cancer cells of B. villosa subsp. drepanensis leaf ethanolic extract were analysed for the first time. In addition, its chemical profile was investigated partitioning the total 70% ethanol extract among ethyl acetate, n-butanol, and water to obtain three residues that were subjected to chromatographic separation. Two flavonol glycosides, a phenol glucoside, two amino acids, and purine/pyrimidine bases were obtained. The presence of the glucosinolate glucoiberin was detected in the water extract by UHPLC-MS analysis. The total polyphenol and flavonoid content of the 70% ethanol extract showed good antioxidant capacities and anti-inflammatory properties by reducing nitric oxide release and reactive oxygen species levels and increasing glutathione in lipopolysaccharide-stimulated RAW 264.7 cells. The extract inhibited the enzymatic activity of α-amylase, α-glucosidase, and, significantly, of lipase. The MTT assay showed that the extract did not affect the viability of normal HFF-1 and RAW 264.7 cells. Among the cancer cell lines tested, an antiproliferative action was only observed in CaCo-2. The cytotoxicity of the extract was further confirmed by LDH release assay and by the destabilization of the oxidative balance. Results confirmed the antioxidant properties of the crude extract responsible for the anti-inflammatory effect on healthy cells and cytotoxicity in cancer cells.

Bioassay-Guided Isolation of Antiproliferative Compounds from Limbarda crithmoides (L.) Dumort.

Limbarda crithmoides (L.) Dumort (Asteraceae) n-hexane extract displayed high cell proliferation inhibitory activity against acute myeloid leukaemia cells (OCI-AML3) and was therefore subjected to a bioassay-guided multistep separation procedure. Two thymol derivatives, namely 10-acetoxy-8,9-epoxythymol tiglate (1) and 10-acetoxy-9-chloro-8,9-dehydrothymol (2), were isolated and identified by means of NMR spectroscopy. Both of them exhibited a significant dose-dependent inhibition of cell proliferation.

Vepris macrophylla (Baker) I. Verd Essential Oil: An Antifungal Agent against Phytopathogenic Fungi.

Rutaceae are widely used in ethnomedicine to treat infectious diseases in humans and plants. In this study, the antifungal activity of the Vepris macrophylla leaf essential oil (VEO) and its main components, citral and citronellol, was evaluated against six phytopathogenic fungi. In addition, the possible action of VEO on the synthesis of mycotoxins was evaluated as well. To determine the antifungal activity of VEO we used the agar dilution method and VEO showed inhibitory activity against all the tested fungi. In particular, VEO resulted to be fungicidal against Phytophthora cryptogea and Fusarium avenaceum. For all other fungi VEO exhibited fungistatic activity and the weakest effect was observed on Alternaria solani. Citral was very effective against P. cryptogea, F. avenaceum, F. poae and F. graminearum. On the other hand, citronellol showed good activity towards P. cryptogea and F. avenaceum and weaker activity towards F. poae and F. graminearum. It can be concluded that VEO can be considered a promising antifungal agent, especially against P. cryptogea and F. avenaceum, suggesting a possible use in the formulation of new selective and natural fungicides.

Oxidative stress and antioxidant responses to increasing concentrations of trivalent chromium in the Andean crop species Chenopodium quinoa Willd.

Quinoa (Chenopodium quinoa Willd), an ancient Andean seed crop, exhibits exceptional nutritional properties and resistance to abiotic stress. The species' tolerance to heavy metals has, however, not yet been investigated nor its ability to take up and translocate chromium (Cr). This study aimed to investigate the metabolic adjustments occurring upon exposure of quinoa to several concentrations (0.01-5mM) of CrCl3. Young hydroponically grown plants were used to evaluate Cr uptake, growth, oxidative stress, and other biochemical parameters three and/or seven days after treatment. Leaves accumulated the lowest amounts of Cr, while roots and stems accumulated the most at low and at high metal concentrations, respectively. Fresh weight and photosynthetic pigments were reduced only by the higher Cr(III) doses. Substantially increased lipid peroxidation, hydrogen peroxide, and proline levels were observed only with 5mM Cr(III). Except for a significant decrease at day 7 with 5mM Cr(III), total polyphenols and flavonoids maintained control levels in Cr(III)-treated plants, whereas antioxidant activity increased in a dose-dependent manner. Maximum polyamine accumulation was observed in 1mM CrCl3-treated plants. Even though α- and γ-tocopherols also showed enhanced levels only with the 1mM concentration, tyrosine aminotransferase (TAT, EC 2.6.1.5) activity increased under Cr(III) treatment in a dose- and time-dependent manner. Taken together, results suggest that polyamines, tocopherols, and TAT activity could contribute to tolerance to 1mM Cr(III), but not to the highest concentration that, instead, generated oxidative stress.

Inhibition of Breast Cancer Cell Proliferation and In Vitro Tumorigenesis by a New Red Apple Cultivar.

PURPOSE: The aim of this study was to evaluate the antiproliferative activity in breast cancer cells and the inhibition of tumorigenesis in pre-neoplastic cells of a new apple cultivar with reddish pulp, called the Pelingo apple. METHODS: The antiproliferative activity was evaluated in MCF-7 and MDA-MB-231 human breast cancer cells. The inhibition of tumorigenesis was performed in JB6 promotion-sensitive (P+) cells. RESULTS: Results showed that Pelingo apple juice is characterized by a very high polyphenol content and strongly inhibited breast cancer cell proliferation. Its antiproliferative activity was found to be higher than the other five apple juices tested. Pelingo juice induced cell accumulation in the G2/M phase of the cell cycle and autophagy through overexpression of p21, inhibition of extracellular signal-regulated kinases 1/2 (ERK1/2) activity and an increase in lipidated microtubule-associated protein-1 light chain-3 beta (LC3B). Remarkably, Pelingo juice inhibited the 12-o-tetra-decanoyl-phorbol-13-acetate (TPA)-induced tumorigenesis of JB6 P+ cells, suppressing colony formation in semi-solid medium and TPA-induced ERK1/2 phosphorylation. CONCLUSIONS: Our data indicate that the Pelingo apple is rich in food components that can markedly inhibit in vitro tumorigenesis and growth of human breast cancer cells and could provide natural bioactive non-nutrient compounds, with potential chemopreventive activity.

Antioxidant and antifungal activity of different extracts obtained from aerial parts of Inula crithmoides L.

The total phenolic content, antioxidant and antifungal activities of three Inula crithmoides extracts (n-hexane, methylene chloride and MeOH) were investigated. The methanolic extract showed the highest total phenolic content. In the DPPH assay, the methanolic and hexane extracts exhibited the highest DPPH-radical scavenging activity; in the 5-lipoxygenase assay, the hexane extract showed greater inhibitory effect with an IC50 similar to that of Trolox and ascorbic acid. The antifungal activity of the methanolic extract revealed a higher activity against Phytophtora cryptogea and Alternaria solani.

Polyphenols profile and antioxidant activity of skin and pulp of a rare apple from Marche region (Italy).

BACKGROUND: Apples are an important source of polyphenols in the human diet and the consumption of this fruit has been linked to the prevention of degenerative diseases. RESULTS: CATECHINS, PROCYANIDINS, HYDROXYCINNAMIC ACIDS, FLAVONOL GLYCOSIDES, DIHYDROCHALCONE GLYCOSIDES AND ONE ANTHOCYANIN: cyanidin-3-O-galactoside, were identified both in the peel and pulp. Procyanidins, catechins and flavonols represent the main constituents of peel. Concerning the antioxidant activity, in the reduction of the stable DPPH radical and in the inhibition of lipid peroxidation, the ethanolic extracts of red peel and red pulp showed a good similar activity comparable to ascorbic acid in the DPPH test and about ten times more active than BHT in the lipoxygenase test, and were much more active than aqueous extracts. The ORAC value of red pulp aqueous extract resulted comparable to that of red berries: vaccinium, rubus and ribes, foods appreciated for their health value. CONCLUSION: This apple contains an appreciable amount of polyphenols also in the flesh; this variety with red flesh can also be useful for researchers engaged in apples varietal innovation in addition to being used as food apple.

Total polyphenol content, in vitro antifungal and antioxidant activities of callus cultures from Inula crithmoides.

This is the first report on the antioxidant and antifungal activities of callus cultures from Inula crithmoides L. (Asteraceae). Callus cultures were initiated from leaf sections, on initial culture MS basal medium supplemented with various concentrations of 2,4-D (2,4-dichlorophenoxyacetic acid), NAA (1-naphthaleneacetic acid) and IBA (indole-3-butyric acid) and a 72% survival was achieved. Significant differences between the various auxins used as phytohormones on callus growth were found. Maximum callusing was noticed on the leaf explants grown on MS basal medium supplemented with 1 mgL(-1) 2,4-D. Subsequently the antioxidant and antimicrobial activities of the methanol extract from calli were investigated. Antioxidant studies suggested that the methanol extracts of dark-grown and light-grown callus were able to reduce the stable free radical 2,2-diphenyl-1-picrilhydrazyl (DPPH). In the inhibition against lipid peroxidation, extracts of dark-grown callus showed the strongest effect with IC50 values better than those of the standards. The methanol extract of callus cultures had significant antifungal activity only against two of the fungi tested: Alternaria solani and Phytophthora cryptogea. Against all the other tested fungi, the I. crithmoides calli extracts showed fungistatic activity.

Total phenolic content and antioxidant activity of Salvia spp. exudates.

The total phenolic content and antioxidant activity of 6 Salvia spp. exudates were measured to find new potential sources of natural antioxidants. Total phenolic content was assessed by a modified Prussian blue method, and the antioxidant activity by two methods: 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging capacity assay and lipoxygenase inhibitory assay. The total phenolic content ranged between 1.3 microg/mg DW (S. fallax) and 74.0 microg/mg DW (S. cacaliaefolia). In the DPPH test, S. cacaliaefolia was more effective than BHT, while in the inhibition of lipid peroxidation all the extracts presented good antioxidant capacity.

Protective effects of Commiphora erythraea resin constituents against cellular oxidative damage.

By bioguided fractionation of the hexane extract of Commiphora erythraea resin we isolated four furanosesquiterpenoids that were tested for their protective activity against oxidative stress. Furanodienone and 1,10(15)-furanogermacra-dien-6-ones showed to be potent inhibitors of lipid peroxidation (IC(50) of -0.087 µM), being more active than the methoxylated analogues. Furthermore, using BV2 microglial cells, we found that furanodienone from C. erythraea is able to counteract LPS-induced cell death and decrease LPS-induced NO generation thus protecting microglial cells from LPS-induced cytotoxicity. Finally, docking studies were undertaken to gain insight into the possible binding mode of the isolated compounds at 5-LOX binding site.

In vitro plant regeneration from callus of Citrus x monstruosa (Pompia), an endemic citrus of Sardinia.

A regeneration protocol was developed from callus obtained from various explants taken from in vitro cultured seedlings (root, leaf and stem internodes) of Citrus x monstruosa. The best treatment in terms of response frequency and mean number of shoots for explants was 35.0 microM BA with 5.5 microM NAA. The best shoot regeneration was obtained with internodal stem segments cut longitudinally with the cut surface in contact with the culture medium and pre-treatment of 21 days of these explants in darkness. The best rooting of explants was obtained on half-strength MS basal medium supplemented with either NAA or IBA at 5.4 microM and 2.5 microM, respectively. Hardening of Citrus x monstruosa was accomplished in 40 days, with 95% survival rate.

Composition and antioxidant activity of Inula crithmoides essential oil grown in central Italy (Marche region).

The chemical composition of the essential oil obtained from the aerial parts of Inula crithmoides L. was analyzed by GC and GC/MS and 22 components were identified, the major ones being p-cymene (30.1%), 1-methylethyl-trimethylbenzene (18.7%), scopoletin (15.3%) and alpha-pinene (13.1%). The antioxidant activity of the oil was evaluated by the DPPH test and 5-lipoxygenase assay. The essential oil exerted a good antioxidant activity in the protection of lipid peroxidation when compared with known antioxidants.

Essential oil composition and antimicrobial activity of Ballota nigra L. ssp foetida.

The chemical composition of the essential oil of Ballota nigra L. ssp foetida obtained from the flowering aerial parts was analyzed by GC/MS. From the 37 identified constituents of the oil, beta-caryophyllene (20.0%), germacrene D (18.0%) and caryophyllene oxide (15.0%) were the major components. The oil was active against both Gram-negative and Gram-positive bacteria as well as against three Candida species.

Prunus spinosa fresh fruit juice: antioxidant activity in cell-free and cellular systems.

The antioxidant activity was assessed of fresh juice from Prunus spinosa L. fruit (Rosaceae) growing wild in Urbino (central Italy) by using different cell-free in vitro analytical methods: 5-lipoxygenase test, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, and oxygen radical absorbance capacity (ORAC). Trolox was used as the reference antioxidant compound. In the 5-lipoxygenase and DPPH tests the fresh fruit juice of P. spinosa showed good antioxidant activity when compared with Trolox, while the ORAC value was 36.0 micromol eq. Trolox/g of fruit. These values are in accord with data reported in the literature for small fruits such as Vaccinium, Rubus and Ribes. The antioxidant capacity in cell-free systems of P. spinosa juice has been compared with its cytoprotective - bona fide antioxidant activity in cultured human promonocytes (U937 cells) exposed to hydrogen peroxide. The antioxidant activity of red berries has been correlated with their anthocyanin content. The results of this study indicate that the three most representative anthocyanins in P. spinosa fruit juice (cyanidin-3-rutinoside, peonidin-3-rutinoside and cyanidin-3-glucoside) are likely to play an important role in its antioxidant properties.

RNA as a new target for toxic and protective agents.

In contrast to damage of genomic DNA and despite its potential to affect cell physiology, RNA damage is a poorly examined field in biomedical research. Potential triggers of RNA damage as well as its pathophysiological implications remain largely unknown. While less lethal than mutations in genome, such non-acutely lethal insults to cells have been recently associated with underlying mechanisms of several human chronic diseases. We investigated whether RNA damage could be related to the exposure of particular xenobiotics by testing the RNA-damaging activity of a series of chemicals with different mechanisms of action. Cultured human T-lymphoblastoid cells were treated with ethyl methanesulfonate (EMS), H(2)O(2), doxorubicin, spermine, or S-nitroso-N-acetylpenicillamine (SNAP). Furthermore, we studied the potential protective activity of a pomegranate extract against RNA damage induced by different chemicals. Special attention has been paid to the protective mechanisms of the extract. The protective effect of pomegranate can be mediated by alterations of the rates of toxic agent absorption and uptake, by trapping of electrophiles as well as free radicals, and protection of nucleophilic sites in RNA. We used two different treatment protocols (pre- and co-treatment) for understanding the mechanism of the inhibitory activity of pomegranate. We demonstrated that total RNA is susceptible to chemical attack. A degradation of total RNA could be accomplished with doxorubicin, H(2)O(2), spermine and SNAP. However, EMS, a well-known DNA-damaging agent, was devoid of RNA-damaging properties, while spermine and SNAP, although lacking of DNA-damaging properties, were able to damage RNA. Pomegranate reduced the RNA-damaging effect of doxorubicin, H(2)O(2), and spermine. Its inhibitory activity could be related with its ability to forms complexes with doxorubicin and H(2)O(2), or interacts with the intracellular formation of reactive species mediating their toxicity. For spermine, an alteration of the rates of spermine absorption and uptake can also be involved.

Melatonin antagonizes apoptosis via receptor interaction in U937 monocytic cells.

Among the non-neurological functions of melatonin, much attention is being directed to the ability of melatonin to modulate the immune system, whose cells possess melatonin-specific receptors and biosynthetic enzymes. Melatonin controls cell behaviour by eliciting specific signal transduction actions after its interaction with plasma membrane receptors (MT(1), MT(2)); additionally, melatonin potently neutralizes free radicals. Melatonin regulates immune cell loss by antagonizing apoptosis. A major unsolved question is whether this is due to receptor involvement, or to radical scavenging considering that apoptosis is often dependent on oxidative alterations. Here, we provide evidence that on U937 monocytic cells, apoptosis is antagonized by melatonin by receptor interaction rather than by radical scavenging. First, melatonin and a set of synthetic analogues prevented apoptosis in a manner that is proportional to their affinity for plasma membrane receptors but not to their antioxidant ability. Secondly, melatonin's antiapoptotic effect required key signal transduction events including G protein, phospholipase C and Ca(2+) influx and, more important, it is sensitive to the specific melatonin receptor antagonist luzindole.

Essential oil composition and antioxidant activity of aerial parts of Grindelia robusta from Central Italy.

The chemical composition of the essential oil obtained from Grindelia robusta aerial parts from central Italy was analyzed by GC and GC/MS and 45 components were identified. Borneol (15.2%), alpha pinene (10.3%), trans-pinocarveol (7.0%), bornyl acetate (4.5%), limonene (4.3%) were the main components. The antioxidant activity of the essential oil was evaluated using the DPPH and 5-lipoxygenase tests.

Cytoprotective effect of preparations from various parts of Punica granatum L. fruits in oxidatively injured mammalian cells in comparison with their antioxidant capacity in cell free systems.

Pomegranate (Punica granatum L.) juice (PJ) is being increasingly proposed as a nutritional supplement to prevent atherosclerosis in humans. This therapeutically valuable potential has been attributed to PJ antioxidant capacity which has been mostly tested by means of cell-free assays: indeed, to the best of our knowledge, no study has focused on the direct antioxidant capacity of PJ in cultured cells. Here, the antioxidant capacity in cell free-systems of preparations from various parts of pomegranate has been compared with their cytoprotective -bona fide antioxidant--activity in cultured human cells (U937 promonocytes and HUVEC endothelial cells) exposed to an array of oxidizing agents. Pomegranate derivatives were PJ, arils only juice (AJ) and aqueous rinds extract (RE). In cell-free assays--1,1-diphenyl-2-picrylhydrazyl (DPPH), chemiluminescence luminol/xanthine/xanthine oxidase and lipoxygenase assays--all the preparations displayed good antioxidant capacity, the relative potency order being RE>PJ>AJ. On the contrary, only RE was capable of preventing the deleterious effects--cytotoxicity, DNA damage and depletion of non-protein sulphydrils (NPSH) pool--caused by treatment of cells with H(2)O(2), tert-butylhydroperoxide (tB-OOH) or oxidized lipoproteins (Ox-LDL) via a mechanism which is likely to involve both direct scavenging of radical species and iron chelation. Surprisingly, AJ and PJ slightly sensitized cells to the cytotoxic effects of the three agents. Then it would appear that AJ, the major and tasty part of PJ, does not contain ellagic acid and punicalagin (i.e. the polyphenols highly represented in RE which are reputed to be responsible for the antioxidant capacity) in amounts sufficient to exert cytoprotection in oxidatively injured, living cells. Based on these results, the development and evaluation of rinds-only based derivatives for antiatherogenic preventive purposes in humans should be encouraged.

Chemical composition, antimicrobial and antioxidant activity of the essential oil of Teucrium marum (Lamiaceae).

The chemical composition of the essential oil obtained from Teucrium marum subsp. marum (Lamiaceae) was analysed by GC/MS and 30 components were identified. Isocaryophyllene (20.24%), beta-bisabolene (14.73%), beta-sesquiphellandrene (11.27%), alpha-santalene (10.97%), dolichodial (9.38%) and, alpha-caryophyllene (7.18%) were the main components. The antimicrobial activity of the essential oil was assayed against four phytopathogenic fungi and Rhyzoctonia solani resulted to be the most sensitive microorganism with a MIC value of 250 ppm. The antioxidant activity of the essential oil was evaluated using the DPPH test, 5-lipoxygenase test and luminol/xanthine/xanthine oxidase chemiluminescence assay.