Volatile composition, antidiabetic, and anti-obesity potential of Brassica incana leaf and flowering top extracts.

CONTEXT: Brassica incana Ten. (Brassicaceae) is an edible plant with very limited available information. Previous studies have demonstrated the polyphenolic profile and the antioxidant and cytotoxic properties of the leaf and flowering top hydroalcoholic extracts. OBJECTIVE: The volatile composition and the antidiabetic and anti-obesity potential of B. incana leaf and flowering top extracts have been investigated. MATERIAL AND METHODS: The volatile characterization of the extracts was attained by HS-SPME-GC/MS analysis. The antidiabetic and anti-obesity potential was investigated spectrophotometrically in vitro by the ability to modulate pancreatic lipase and α-glucosidase at different concentrations using orlistat and acarbose as reference drugs. The inhibition of advanced glycation end-products (AGEs) was measured with aminoguanidine as reference and the antioxidant activity with the xanthine/xanthine oxidase system and Trolox for comparative purposes. RESULTS: Several volatiles belonging to different chemical classes were identified, being sulphur compounds the most abundant in both leaf and flowering top extracts (56.33% and 64.40% of all volatiles). Although the leaf extract showed lower IC50 values in most of the assays (0.968 and 1.921 mg/mL for α-glucosidase; 0.192 and 0.262 mg/mL for AGEs; 0.022 and 0.038 mg/mL for superoxide scavenging), there were no statistically significant differences between both samples. These extracts showed a similar behaviour to Trolox in the xanthine oxidase assay (IC50 values of 0.022 mg/mL for leaf extract; 0.038 mg/mL for flowering top and 0.028 for Trolox). CONCLUSIONS: Leaves and flowering tops from B. incana can be used as sources of functional compounds that could act as antidiabetic and anti-obesogenic agents.

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.

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.

Chemopreventive glucosinolate accumulation in various broccoli and collard tissues: Microfluidic-based targeted transcriptomics for by-product valorization.

Floret, leaf, and root tissues were harvested from broccoli and collard cultivars and extracted to determine their glucosinolate and hydrolysis product profiles using high performance liquid chromatography and gas chromotography. Quinone reductase inducing bioactivity, an estimate of anti-cancer chemopreventive potential, of the extracts was measured using a hepa1c1c7 murine cell line. Extracts from root tissues were significantly different from other tissues and contained high levels of gluconasturtiin and glucoerucin. Targeted gene expression analysis on glucosinolate biosynthesis revealed that broccoli root tissue has elevated gene expression of AOP2 and low expression of FMOGS-OX homologs, essentially the opposite of what was observed in broccoli florets, which accumulated high levels of glucoraphanin. Broccoli floret tissue has significantly higher nitrile formation (%) and epithionitrile specifier protein gene expression than other tissues. This study provides basic information of the glucosinolate metabolome and transcriptome for various tissues of Brassica oleracea that maybe utilized as potential byproducts for the nutraceutical market.

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.

Rice TUTOU1 Encodes a Suppressor of cAMP Receptor-Like Protein That Is Important for Actin Organization and Panicle Development.

Panicle development, a key event in rice (Oryza sativa) reproduction and a critical determinant of grain yield, forms a branched structure containing multiple spikelets. Genetic and environmental factors can perturb panicle development, causing panicles to degenerate and producing characteristic whitish, small spikelets with severely reduced fertility and yield; however, little is known about the molecular basis of the formation of degenerating panicles in rice. Here, we report the identification and characterization of the rice panicle degenerative mutant tutou1 (tut1), which shows severe defects in panicle development. The tut1 also shows a pleiotropic phenotype, characterized by short roots, reduced plant height, and abnormal development of anthers and pollen grains. Molecular genetic studies revealed that TUT1 encodes a suppressor of cAMP receptor/Wiskott-Aldrich syndrome protein family verprolin-homologous (SCAR/WAVE)-like protein. We found that TUT1 contains conserved functional domains found in eukaryotic SCAR/WAVE proteins, and was able to activate Actin-related protein2/3 to promote actin nucleation and polymerization in vitro. Consistently, tut1 mutants show defects in the arrangement of actin filaments in trichome. These results indicate that TUT1 is a functional SCAR/WAVE protein and plays an important role in panicle development.

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.

Characterization of FLOWERING LOCUS T1 (FT1) gene in Brachypodium and wheat.

The phase transition from vegetative to reproductive growth is a critical event in the life cycle of flowering plants. FLOWERING LOCUS T (FT) plays a central role in the regulation of this transition by integrating signals from multiple flowering pathways in the leaves and transmitting them to the shoot apical meristem. In this study, we characterized FT homologs in the temperate grasses Brachypodium distachyon and polyploid wheat using transgenic and mutant approaches. Downregulation of FT1 by RNAi was associated with a significant downregulation of the FT-like genes FT2 and FT4 in Brachypodium and FT2 and FT5 in wheat. In a transgenic wheat line carrying a highly-expressed FT1 allele, FT2 and FT3 were upregulated under both long and short days. Overexpression of FT1 caused extremely early flowering during shoot regeneration in both Brachypodium and hexaploid wheat, and resulted in insufficient vegetative tissue to support the production of viable seeds. Downregulation of FT1 transcripts by RNA interference (RNAi) resulted in non-flowering Brachypodium plants and late flowering plants (2-4 weeks delay) in wheat. A similar delay in heading time was observed in tetraploid wheat plants carrying mutations for both FT-A1 and FT-B1. Plants homozygous only for mutations in FT-B1 flowered later than plants homozygous only for mutations in FT-A1, which corresponded with higher transcript levels of FT-B1 relative to FT-A1 in the early stages of development. Taken together, our data indicate that FT1 plays a critical role in the regulation of flowering in Brachypodium and wheat, and that this role is associated with the simultaneous regulation of other FT-like genes. The differential effects of mutations in FT-A1 and FT-B1 on wheat heading time suggest that different allelic combinations of FT1 homoeologs could be used to adjust wheat heading time to improve adaptation to changing environments.

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).

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.

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.

Coffee, broccoli and spices are strong inducers of electrophile response element-dependent transcription in vitro and in vivo - studies in electrophile response element transgenic mice.

SCOPE: Cytoprotective gene products, e.g. phase II - and antioxidant enzymes, are important in cellular redox homeostasis. A common feature of these genes is binding sites for transcription factor nuclear factor erythroid-2-related factor 2 (Nrf2), named electrophile response elements (EpREs) within their promoters. METHODS AND RESULTS: To identify dietary bioactive compounds and foods with Nrf2/EpRE inducing properties in an intact organism, we utilized transgenic mice encoding luciferase under control of EpRE from the thioredoxin promoter. We found that 18 of 31 phytochemicals and 10 of 14 dietary plant extracts induced EpRE activity in liver HepG2 cells. Surprisingly, some dietary plant extracts showed profound inducing capability as compared to pure compounds indicating combinatorial effects of compounds found in whole foods. Furthermore, intraperitoneal injections of carnosol, curcumin and tert benzohydroquinine induced EpRE-dependent promoter activity in transgenic mice. In further experiments with curcumin, we found highly induced EpRE activity in intestine, liver, kidney and spleen. Finally, a combination extract made of coffee, thyme, broccoli, rosemary, turmeric and red onion fed orally, induced EpRE mediated luciferase in lung and adipose tissue. CONCLUSION: These results show that plant-based foods contain compounds that can be absorbed and induce the antioxidant defence in a living organism in an organ-specific manner.

Seven new dammarane triterpenes from the floral spikes of Betula platyphylla var. japonica.

Seven new dammarane-type triterpenoids, including two 20(S)-hydroxy-25-methoxy-dammar-23-enes (1 and 2), two 20(S),24(R)-epoxydammaranes (3 and 4), a cabralealactone (5), and two 20(S),25-epoxydammaranes (6 and 7), together with seven known triterpenes (8-14), were isolated from the floral spikes of Betula platyphylla var. japonica. The structures for all compounds were elucidated by the analyses of extensive spectroscopic data, as well as chemical examinations.