Promising effects of Rosa damascena petal extracts as antioxidant and antibacterial agents.

In the present work, the antioxidant properties of methanolic (MeOH), ethyl acetate (EtOAc) and chloroformic (CHCl3) fractions of Rosa damascena petals were evaluated. Antioxidant capacity was assessed by free radical scavenging assays (DPPH•) and ferrous ions (Fe2+) chelating activity. Antibacterial activity was evaluated using minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and IC50. Qualitative analysis of chemical composition was carried out by HPLC and showed variability in the chemical constituents with a richness in flavonones and phenolic acids. Acute toxicity study and hemolysis test were also assessed. The MeOH and EtOAc fractions are of real and potential interest by their antioxidant activities. Furthermore, the microbiological study of the fractions showed a high activity of the EtOAc fraction which possesses bactericidal properties, followed by a moderate activity of the methanolic MeOH. The most sensitive strains were S. aureus and B. cereus while the most resistant were P. aeruginosa and E. coli (R). On the other side, no cytotoxicity was observed towards erythrocytes isolated from human blood and on a warm-blooded animal model. Therefore, the R. damascena petals constitute a promising source of molecules for clinical use without cytoxicity.

Evaluation of Anti-Diabetic Potential of Corn Silk in High-Fat Diet/ Streptozotocin-Induced Type 2 Diabetes Mice Model.

BACKGROUND: Corn silk is the elongated stigma of the female flower of Zea mays and traditionally used to treat diabetes mellitus (DM). OBJECTIVE: To investigate the beneficial effects of corn silk extract (CSE) on HFD/STZ-induced diabetic C56BL/6J mice. METHODS: Establishment of a T2DM model through feeding HFD combined with STZ. T2DM was randomly divided into 5 groups: diabetic control mice treated with vehicle (model group, n=10), metformin- treated group (metformin: 150 mg/kg.d, n=10), three CS-treated groups (CS: 300, 600 and 1200 mg/kg.d, n=10). After four weeks of CS treatment, the body weight, FBG, IR, TC, TG, LDL-C, MDA and SOD levels of mice were measured. In addition, the liver tissue was histomorphologically analyzed by HE stain followed a light microscopy observation. RESULTS: 4-week CSE treatment significantly reduced FBG and enhanced the glucose tolerance; improved IR indicated by decreased HOMA-IR and elevated ISI; alleviated hyperlipidemia indicated by decreased TC, TG, LDL-C, and increased HDL-C; reduced oxidative stress by decreased MDA and elevated SOD activity; decreased hepatic lipid accumulation and prevented liver tissue morphological change in T2DM. In addition, CSE treatments effectively prevent the weight gain loss of diabetic mice. CONCLUSION: These results confirmed the traditionally claimed benefits of corn silk on DM, which suggested that the corn silk possessed the anti-diabetic potential and could be further developed as a cheap and plant-derived agent for the treatment of type 2 diabetes mellitus.

Cytotoxic saponins and other natural products from flowering tops of Narthecium ossifragum L.

For more than four centuries, the intake of Narthecium ossifragum has been associated with poisoning in domesticated animals. Saponins occurring in flowering tops of the plant are considered to cause kidney damage in calves. At present, there are more than 30 papers on the saponins of N. ossifragum in the literature, although the structures of these compounds have hitherto not been determined. Here, we identify the saponins of N. ossifragum as sarsasapogenin, sarsasapogenin-3-O-ß-galactopyranoside, sarsasapogenin-3-O-(2'-O-ß-glucopyranosyl-ß-galactopyranoside) and sarsasapogenin-3-O-(2'-O-ß-glucopyranosyl-3'-O-α-arabinopyranosyl-ß-galactopyranoside). Moreover, six aromatic natural products were isolated and characterized from the methanolic extract from flowers of N. ossifragum. Five of these aromatic compounds, chrysoeriol 6-C-ß-arabinofuranoside-8-C-ß-glucopyranoside, chrysoeriol 6-C-ß-arabinopyranosyl-8-C-ß-glucopyranoside, chrysoeriol 6-C-ß-xylopyranosyl-8-C-ß-galactopyranoside, chrysoeriol 6-C-ß-galactopyranosyl-8-C-ß-glucopyranoside and chrysoeriol 6-C-ß-glucopyranosyl-8-C-ß-galactopyranoside are undescribed. All compounds were tested for cytotoxicity in mammalian cell lines derived from the heart, kidney, and haematological tissues. The saponins exhibited cytotoxicity in the micromolar range, with proportionally increasing cytotoxicity with increasing number of glycosyl substituents. The most potent compound was the main saponin sarsasapogenin-3-O-(2'-O-ß-glucopyranosyl-3'-O-α-arabinopyranosyl-ß-galactopyranoside), which produced cell death at concentrations below 3-4 µM in all three cell lines tested. This indicates that the saponins are the toxicants mainly responsible for kidney damage observed in cattle after ingestion of N. ossifragum. Our findings also pave the way for analysis of individual compounds isolated during the biopsies of intoxicated animals.

Clove attenuates UVB-induced photodamage and repairs skin barrier function in hairless mice.

Syzygium aromaticum L., commonly named clove, is widely used in the food industry due to its antioxidant and antibacterial capabilities. However, little information is available regarding its role in resisting skin photoaging. This study investigated 50% ethanol extract of Syzygium aromaticum L. (SA) and eugenol (EO) for anti-aging effects in UVB-irradiated normal human dermal fibroblasts (NHDFs) and hairless mice. In vitro, SA and EO suppressed matrix metalloproteinase-1, 3 (MMP-1 and MMP-3) secretion as well as the activator protein 1 (AP-1) phosphorylation. SA and EO also activated nuclear erythroid 2-related factor/antioxidant-response element (Nrf2/ARE) signaling which improves the antioxidant activity and inhibited nuclear factor-κB (NF-κB) and interleukin-6 (IL-6) expression, pro-inflammatory factors. Furthermore, SA and EO suppressed the nuclear factor of activated T cells c1 (NFATc1) which is a known activator of MMPs, cooperator transforming growth factor beta (TGF-ß) and NF-κB in Ca2+/calcineurin-regulated transcription. In vivo, SA significantly improved the levels of procollagen type I and elastin through TGF/Smad signaling. The histopathological studies found that SA reduced wrinkles. SA also increased filament aggregating protein (filaggrin), which repairs the skin barrier function and improved the skin's hydration. Altogether, SA effectively ameliorated UVB-induced photoaging. It is expected to become a promising natural product.

Heavy metals in vegetables sold in the local market in Jordan.

Heavy metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) in various vegetables (cabbage, green onion, lettuce, parsley, rocket, spinach, carrot, onion, potato and cauliflower) from the market in Jordan were measured using inductively coupled plasma-mass spectrometry. As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn ranged from 0.009-0.275 mg kg(-1) wet weight, 0.004-0.060 mg kg(-1), 0.003-0.401 mg kg(-1), 0.105-3.51 mg kg(-1), 0.15-1.15 mg kg(-1), 0.93-14.39 mg kg(-1), 0.044-0.702 mg kg(-1), 0.072-0.289 mg kg(-1) and 2.23-6.65 mg kg(-1), respectively. Parsley, followed by spinach, contained the highest concentration of heavy metals. Onion contained high levels of toxic heavy metals. The content of Cu in parsley and spinach and Pb in onion exceeded the Codex limits. However, the daily intake of heavy metals from the tested vegetables was lower than the maximum limits for allowable intake.

Extraction of bioactive carbohydrates from artichoke (Cynara scolymus L.) external bracts using microwave assisted extraction and pressurized liquid extraction.

Microwave assisted extraction (MAE) and pressurized liquid extraction (PLE) methods using water as solvent have been optimized by means of a Box-Behnken and 3(2) composite experimental designs, respectively, for the effective extraction of bioactive carbohydrates (inositols and inulin) from artichoke (Cynara scolymus L.) external bracts. MAE at 60 °C for 3 min of 0.3 g of sample allowed the extraction of slightly higher concentrations of inositol than PLE at 75 °C for 26.7 min (11.6 mg/g dry sample vs. 7.6 mg/g dry sample). On the contrary, under these conditions, higher concentrations of inulin were extracted with the latter technique (185.4 mg/g vs. 96.4 mg/g dry sample), considering two successive extraction cycles for both techniques. Both methodologies can be considered appropriate for the simultaneous extraction of these bioactive carbohydrates from this particular industrial by-product. To the best of our knowledge this is the first time that these techniques are applied for this purpose.

Comparative study on the antioxidant activities of extracts of Coreopsis tinctoria flowering tops from Kunlun Mountains, Xinjiang, north-western China.

Coreopsis tinctoria flowering tops (CTFs) from the Kunlun Mountains in Xinjing (north-western China) have been used for tea production for about a century. This study aims to assess the antioxidant activities and total phenolic, flavonoid and proanthocyanidin contents of various solvent extracts of CTF. CTF was extracted using n-hexane, chloroform, ethyl acetate, n-butanol, 75% aqueous ethanol (AEE) and water. The antioxidant activities of the CTF extracts were investigated through DPPH, ABTS, *OH, *O2(-), total antioxidant capacity and reducing power assays. The results showed that n-butanol extract showed the highest contents of total phenols and flavonoids, with DPPH, ABTS and *OH radical-scavenging activities with IC50 values of 134, 90.72 and 13.8 µg mL(-1), respectively. The AEE demonstrated the strongest DPPH and ABTS radical-scavenging activities, with IC50 values of 103 and 75.16 µg mL(-1), respectively. Given its high antioxidant effect, CTF is a good source of natural antioxidants or functional food materials.

Chemical composition, N-nitrosamine inhibition and antioxidant and antimicrobial properties of essential oil from Coreopsis tinctoria flowering tops.

Coreopsis tinctoria flowering (CTF) tops from the Kunlun Mountains in Xinjing (north-western China) have been used for tea production for about a century. This study was to assess antioxidant, nitrite-scavenging and N-nitrosamine inhibitory and antimicrobial activities of the essential oil extracted from CTF tops. The essential oil was extracted through hydrodistillation and its chemical compositions were analysed by GC-MS. Seventy compounds of the oil were identified, representing 81.87% of total oil. The antioxidant capacities of the oil with IC50 values for scavenging DPPH and ABTS were 287.66 ± 12.60 and 1.251 ± 0.127 µg mL(- 1), respectively. The nitrite-scavenging and N-nitrosamine inhibitory activities (IC50) were 0.3912 ± 0.0127 and 0.6564 ± 0.036 µg mL(- 1), respectively. The oil has a certain antimicrobial capacity, but its capacity was weaker than that of penicillinG (24 µg mL(- 1)). The oil showed antioxidant and antimicrobial capacities and had a stronger nitrite-scavenging and N-nitrosamine inhibitory properties.

Infusions of artichoke and milk thistle represent a good source of phenolic acids and flavonoids.

Cynara scolymus L. (artichoke) and Silybum marianum (L.) Gaertn (milk thistle) are two herbs well-known for their efficiency in the prevention/treatment of liver injuries, among other chronic diseases. Therefore, the aim of this work was to characterize specific bioactive components, phenolic compounds, in hydromethanolic extracts but also in infusions (the most commonly used preparations) obtained from the whole plant of milk thistle and artichoke. The phenolic profiles were accessed using HPLC-DAD-MS/ESI. Infusions of both species presented higher phenolic contents than the hydromethanolic extracts. Milk thistle presented a similar phenolic composition between the two preparations, revealing only differences in the quantities obtained. Nevertheless, artichoke revealed a slightly different profile considering infusion and hydromethanolic extracts. Apigenin-7-O-glucuronide was the major flavonoid found in milk thistle, while luteolin-7-O-glucuronide was the most abundant in artichoke. Therefore, infusions of both artichoke and milk thistle represent a good source of bioactive compounds, especially phenolic acids and flavonoids.

Phytochemical analysis, biological evaluation and micromorphological study of Stachys alopecuros (L.) Benth. subsp. divulsa (Ten.) Grande endemic to central Apennines, Italy.

Stachys alopecuros subsp. divulsa (Lamiaceae), a perennial herb endemic to central Italy growing on mountain pastures, was investigated for the first time for the content of secondary metabolites, for the micromorphology and histochemistry of glandular trichomes, and for the biological activity of the volatile oil, namely cytotoxic, antioxidant and antimicrobial. The plant showed the molecular pattern of iridoids, among which a new iridoid diglycoside (4'-O-ß-D-galactopyranosyl-teuhircoside) was detected, together with a sterol glucoside and a phenylethanoid glycoside. The essential oil from the flowering aerial parts was characterized by a high proportion of sesquiterpene hydrocarbons (65.1%), with (E)-caryophyllene (33.2%) as the most abundant, while other main components were germacrene D (7.6%), α-humulene (6.4%) and the oxygenated cis-sesquisabinene hydrate (10.2%). Taken together, polar and apolar chemical profiles support the classification of the species within the section Betonica of the genus Stachys. Micromorphological study revealed three types of glandular hairs secreting different classes of compounds, with type A peltate hairs producing the bulk of the essential oil. MTT assay revealed the potential of the volatile oil in inhibiting A375, HCT116 and MDA-MB 231 tumor cells (IC50 values below 20 µg/ml).

Quality parameters and antioxidant properties in organic and conventionally grown broccoli after pre-storage hot water treatment.

BACKGROUND: Demand for broccoli has increased due to its high content of bioactive compounds. However, broccoli is a perishable commodity with a short shelf life mainly due to dehydration, yellowing and losses of bioactive compounds. Thus, efficient treatments to preserve broccoli quality are needed. RESULTS: The effect of heat treatment on senescence and antioxidant compounds evolution during storage at 20 °C was evaluated in organic and conventionally grown broccoli. Senescence evolved quickly as manifested by floral head yellowing, which was higher in conventional than in organic broccolis, but senescence was significantly delayed by heat treatment. All organic acids, including ascorbic acid, were found at higher concentrations in organic than in conventional broccoli at harvest but decreased during storage in all broccolis. Phenolic concentration and antioxidant activity (in both hydrophilic and lipophilic fractions) also decreased during storage, although these decreases were higher in conventional than in organic broccolis, and no differences were found attributable to heat treatment. CONCLUSIONS: Heat treatment was effective in delaying broccoli senescence, manifested by chlorophyll retention. In addition, organic broccoli maintained higher concentrations of bioactive compounds (ascorbic acid and phenolics) and antioxidant potential during storage than conventional broccoli, with higher potential health beneficial effects.

Maintaining quality and bioactive compounds of broccoli by combined treatment with 1-methylcyclopropene and 6-benzylaminopurine.

BACKGROUND: Broccoli deteriorates very quickly after harvest at ambient temperature due to the loss of green colour and the consequent yellowing of florets. To search for an effective method to control quality deterioration, the effect of 1-methylcyclopropene (1-MCP) combined with 6-benzylaminopurine (6-BA) treatment on visual quality, antioxidant enzymes and bioactive compounds in broccoli florets were investigated. RESULTS: A combined treatment of 2.5 µL L⁻¹ 1-MCP and 200 mg L⁻¹ 6-BA significantly reduced the increase of lightness (L*) value, and retained a high level for the hue value (H) and chlorophyll content. Superoxide dismutase, ascobate peroxidase and catalase activities increased while the activity of peroxidase decreased during storage in treated samples in comparison with the controls. The combined treatment enhanced the biosynthesis of glucosinolate and the formation of the anticarcinogen sulforaphane, which improved the health benefit of broccoli. CONCLUSION: These results indicate that a combined treatment of 1-MCP and 6-BA could be a good candidate for maintaining the visual quality and enhancing the nutritional value in broccoli during storage at 15 °C.

Hop (Humulus lupulus L.) extract inhibits obesity in mice fed a high-fat diet over the long term.

Hops (Humulus lupulus L.) are traditionally used to add bitterness and flavour to beer. Although the isomerised hop extracts produced by the brewing process have been thought to ameliorate lipid and glucose metabolism, the influence of untreated hop extracts on high-fat (HF) diet-induced obesity is unclear. The present study examined the anti-obesity effects of a hop extract in male C57BL/6J mice fed a HF diet, or HF diet plus 2 or 5 % hop extract for 20 weeks. The oral glucose tolerance test was performed at week 19. Furthermore, water excretion was evaluated in water-loaded Balb/c male mice. The effects of the extract on lipid accumulation and PPARγ expression in 3T3-L1 adipocytes were examined. The hop extract inhibited the increase in body and adipose tissue weight, adipose cell diameter and liver lipids induced by the HF diet. Furthermore, it improved glucose intolerance. The extract enhanced water excretion in water-loaded mice. Various fractions of the hop extract inhibited lipid accumulation and PPARγ expression in 3T3-L1 adipocytes. Hop extracts might be useful for preventing obesity and glucose intolerance caused by a HF diet.

An overview of health-promoting compounds of broccoli (Brassica oleracea var. italica) and the effect of processing.

Broccoli offers many heath-promoting properties owing to its content of antioxidant and anticarcinogenic compounds. The concentration and bioavailability of polyphenols, glucosinolates, sulforaphane and selenium depend on plant biochemistry, cultivation strategy and type of processing. In this article, the main biochemical properties of broccoli are reviewed regarding their health-promoting effects. Additionally, the way these properties are affected by processing is discussed. Steaming and drying result in an apparent increment of sulforaphane content as well as antioxidant activity, most likely due to an increase of the extractability of antioxidants and sulforaphane. Freezing and boiling diminish polyphenols concentration, mainly due to volatilization and leaching into the cooking water. In view of these results, the optimization of broccoli processing in order to maximize the content of bioactive compounds should be possible. The effect of processing on selenium compounds has been poorly studied so far, and therefore this topic should be investigated in the future. Finally, the effect of operating conditions in different drying processes on the content of bioactive compounds in broccoli should be investigated in a greater depth.

Revisiting extraction of bioactive apocarotenoids from Crocus sativus L. dry stigmas (saffron).

An ultrasound assisted extraction method is proposed for the recovery of bioactive glycosides (i.e. crocins and picrocrocin) from Crocus sativus L. dry stigmas using aqueous methanol. Response surface methodology (RSM) was employed to optimize the extraction parameters, namely, the percentage of methanol (%), the duration (min) and the duty cycles (s) of sonication. Optical microscopy, spectrophotometry and RP-HPLC-DAD were employed to follow pros and cons of the process. Additional experiments were conducted to compare recoveries with those under other agitation conditions (e.g. magnetic stirring according to ISO 3632-2 standard). The percentage of methanol, the sonication duration and duty cycles combination that can be recommended as optimum for the recovery of crocins and picrocrocin were 50%, 30 min, 0.2s and 0.44%, 30 min, 0.6s, respectively. Picrocrocin levels were not influenced dramatically under the optimum conditions for crocins extraction (11±2 instead of 12±1 mg kg(-1) dry stigmas, respectively) so that these can be considered optimum for both categories of tested compounds. Ultrasound assisted extraction speeded up further recovery of these precious apocarotenoids. Our findings for extraction conditions are useful for both industrial and analytical applications and should be considered in a forthcoming revision of the ISO 3632-2 technical standard.

Changes in bioactive components related to the harvest time from the spicas of Prunella vulgaris.

CONTEXT: Prunella vulgaris L. (Labiatae) is a perennial plant common in China and Europe and is rich in rosmarinic acid (RA), ursolic acid (UA), and oleanolic acid (OA). The dried spica of P. vulgaris has been used as traditional medicine in China for over a hundred years. To our best knowledge, no study has been conducted to determine the influence of harvesting time on concentrations of bioactive compounds of P. vulgaris. OBJECTIVE: In the current study, changes in the bioactive compounds present in spicas were investigated at five harvest times over 2 months. MATERIALS AND METHODS: Plant material were collected at five fixed dates: 5th May, 20th May, 7th June, 15th June, and 25th June and assayed for chemical contents by high-performance liquid chromatography (HPLC). RESULTS: Among the different harvest times, the highest levels of RA (56.81 mg·g⁻¹), UA (2.77 mg·g⁻¹), and OA (0.91 mg·g⁻¹) were found on 5th May, whereas the lowest levels of RA (1.66 mg·g⁻¹), UA (2.27 mg·g⁻¹), and OA (0.43 mg·g⁻¹) were observed on 25th June. DISCUSSION AND CONCLUSION: As each medicinal product has its own content requirement for different bioactive components, the optimum harvest time might be determined according to the accumulation dynamics of target compound in dried spicas of P. vulgaris. These results may be useful for determining the optimal harvest time when bioactive components are at the maximum level, which is in early May.

Composition of the essential oils from Peucedanum cervaria and P. alsaticum growing wild in the urban area of Vienna (Austria).

The composition of the essential oil from the different above ground plant parts of Peucedanum cervaria and P. alsaticum (Apiaceae) collected in the urban area of Vienna has been studied. P. cervaria fruits and inflorescences had 1.5 and 1.8% essential oil, respectively. All the oils of P. cervaria were dominated by monoterpenes, with the main components being beta-pinene (7-58%), alpha-pinene (7-22%), sabinene (up to 22%), and beta-phellandrene with limonene (6-21%). P. alsaticum fruits afforded 0.3-0.4% essential oil. These oils were made up mainly by alpha-pinene (11-40%), sabinene (16-34%) and beta-phellandrene (12-31%). Stems and leaves produced only very small amounts of essential oil (< 0.05%). Besides monoterpenes, these oils contained also E-nerolidol (5-22%), spathulenol (up to 18%), dodecanal (up to 7.5%) and caryophyllene oxide (up to 7%).

Total flavonoid content in varieties of Calendula officinalis L. originating from different countries and cultivated in Estonia.

Total flavonoid contents in the inflorescences of different varieties of Calendula officinalis L. were investigated. The commercial seeds (20 samples) of varieties of C. officinalis originating from eight European countries were cultivated in home gardens in two different counties of Estonia. Total flavonoid contents, determined spectrophotometrically (λ = 370 nm), varied from each other by more than three times (0.21-0.68%) in the investigated varieties. The variety with the highest flavonoid content was 'Kablouna', produced by the Finnish company Siemen (0.68%). Other varieties with high flavonoid content, such as 'Touch of Red' produced by the Latvian company Kurzemes Seklas (0.55%), 'Golden Emperor' produced by the Finnish company Suvipiha (0.50%), 'Pomyk' from Poland (0.50%), etc., may also be preferred for cultivation as natural sources, as they are also rich in flavonoids. The amount of total flavonoids depends on the variety and/or the place and time of cultivation. There appeared to be no conclusive relationship between the total flavonoid content and the colour of ligulate and tubular florets of C. officinalis.