Search results for "LEAVES"

Chemical composition, antimicrobial and antioxidant activity of the essential oils from Pimpinellatragium Vill. subsp. glauca (C. Presl.) C. BrulloBr…

2013

The essential oils from flowers, leaves and stems hydrodistilled from Pimpinella tragium Vill, subsp. glauca were characterised by GC and gas chromatography-mass spectrometry analysis. The C-12 nor-sesquiterpenes are the principal class of metabolites (56.6-70.6%) among which geijerene (28.9÷49.3%) and pregeijerene (10÷19.1%) predominate. Antimicrobial and antioxidant activities were evaluated. The minimum inhibitory concentration values indicate that oil obtained from the stems is the most active for antimicrobial activities and the sample with the biggest antioxidant capacity is the flower oil.

Chemical Profile and Biological Activity of Cherimoya (Annona cherimola Mill.) and Atemoya (Annona atemoya) Leaves

2020

Annona cherimola (Cherimoya) and Annona atemoya (Atemoya) are tropical plants known for their edible fruit. Scientific data suggest that their leaves, used in traditional medicine in the form of teas or infusions without evidence of toxicity, contain several bioactive compounds. However, only Annona muricata among all the Annona species is currently used in the nutraceutical field, and its dried leaves are marketed for tea preparation. In this work, we explored the nutraceutical potential of Atemoya and Cherimoya leaves, by evaluating their chemical profile and functional properties. Phytochemical analyses showed large amounts of phenolic compounds, in particular proanthocyanidins, and iden…

Demonstration of a correlation between young leaves, apex and young bunches specific to a young grapevine cutting in the first period of its developm…

2001

<p style="text-align: justify;">The development of hardwood cutting of grapevine comprise 4 succesive phases. Phase I: first period of shoot extension. Phase II: characterized by a slow growth due to a very low activity of the terminal bud. Phase III: reactivation of the growth consecutive to a resumption of the apical activity. Phase IV: when the growth becomes maximal.</p><p style="text-align: justify;">The objective of this work has been to identify the cause of the slowdown of the activity of apical bud during the phase II.</p><p style="text-align: justify;">In a first experiment, we have compared the effects of three modes of defoliation applied from the b…

Thilachium madagascariense (Capparaceae), a new species from eastern Madagascar with a key to the species of the genus

2021

SummaryThilachium madagascariense Fici, a small tree characterised by 1-foliolate leaves with articulate petioles, leaf blades elliptic or narrowly obovate with base attenuate and apex acuminate, flowers in groups of 2 – 3 at the top of lateral twigs and a high number of stamens, is described and illustrated from forest habitats of eastern Madagascar. The new species is similar to T. laurifolium Baker, a species endemic to central and eastern Madagascar, differing in the longer leaves with acuminate apex, flowers conferted at the top of lateral twigs, shorter pedicels, higher number of stamens and shorter gynophore. Its affinities are discussed and an updated key is provided for all the spe…

Changes of morphogenic competence in mature Pinus sylvestris L. buds in vitro.

2002

The effects of season and cold storage on morphogenic competence in mature Pinus sylvestris buds were investigated. Peroxidase and polyphenol oxidase activity were measured as markers of oxidative metabolism. No growth in vitro was observed on explants detached from the end of January until the beginning of March. Brachioblasts, each with a couple of needles, formed on 11 % of the buds without macrostrobili that were detached in early April and introduced immediately into culture. Of the explants detached in late July, 15 % formed shoots with brachioblasts and needles. The lowest activity of peroxidase and polyphenol oxidase in pine buds was observed from the end of April until the beginnin…

Effects of the silencing of sorbitol dehydrogenase on sugar partitioning in vegetative sinks in apple

2011

Green extraction approach for the recovery of polyphenols from Croatian olive leaves (Olea europea)

2017

Abstract Pressurized liquid extraction (PLE) is shown as an innovative green technology for the effective extraction of the various phytochemicals from food by-products, therefore the aims of this study were to evaluate the application of PLE to engineer green extracts of Croatian olive leaves ( Olea europaea , cv. Oblica) for potential industrial production (functional foods/pharmaceuticals). PLE was conducted under various cycle numbers (1, 2), temperature (60, 80, 100 °C) and static times (5, 10, 15 min). Obtained extracts were characterized in terms of: (i) total polyphenols (TP); (ii) total flavonoids (TF); hydroxycinnamic acids (HCA); and (iv) flavonols (FLA). Response surface methodo…

Application of pressurized fluid extraction to determine cadmium and zinc in plants

2006

Abstract A procedure for the determination of Cd and Zn in plants is proposed. The metals are extracted by pressurized fluid extraction (PFE). Operational conditions are: pressure 1500 psi, temperature 75 °C, static time 5 min, flush volume 35%, purge time 60 s, cycles 1 and 1,2-diaminocyclohexane- N , N , N ′, N ′-tetraacetic acid (CDTA) 0.01 M at pH 4.5 as extracting solution. Determination of Zn is carried out by flame atomic absorption spectroscopy and depending on the concentration level, Cd content is determined by flame or electrothermal atomic absorption spectroscopy. Certified samples of Virginia tobacco leaves, tea leaves, spinach leaves, poplar leaves, a commercial spinach sample…

Chlorophyll content in senescent Pelargonium graveolens leaves

2019

Pelargonium graveolens należy do rodziny Geraniaceae. Roślina ta jest aromatycznym, owłosionym krzewem, sięgającym 1,2 metra wysokości i osiągającym 1 m szerokości. Jej liście są mocno powcinane, miękkie w dotyku i wydzielają intensywny zapach, natomiast kwiaty są małe, zwykle różowe, zebrane w baldachy. Ojczyzną P. graveolens jest Afryka Południowa, ale uprawia się ją obecnie w wielu krajach świata, np. wyspie Reunion, Egipcie, Rosji, Chinach czy Maroko, głównie z przeznaczeniem na produkcję olejku eterycznego. Wykorzystywany jest on w wielu gałęziach przemysłu, m.in. perfumiarstwie, kosmetyce, przemyśle spożywczym czy medycynie. Dane literaturowe pokazują, że o kondycji całej rośliny świa…

Combined dynamics of the 500–600 nm leaf absorption and chlorophyll fluorescence changes in vivo: Evidence for the multifunctional energy quenching r…

2021

Carotenoids (Cars) regulate the energy flow towards the reaction centres in a versatile way whereby the switch between energy harvesting and dissipation is strongly modulated by the operation of the xanthophyll cycles. However, the cascade of molecular mechanisms during the change from light harvesting to energy dissipation remains spectrally poorly understood. By characterizing the in vivo absorbance changes (Delta A) of leaves from four species in the 500-600 nm range through a Gaussian decomposition, while measuring passively simultaneous Chla fluorescence (F) changes, we present a direct observation of the quick antenna adjustments during a 3-min dark-to-high-light induction. Underlying…