Children Exhibit a More Comparable Neuromuscular Fatigue Profile to Endurance Athletes Than Untrained Adults

The present study compared neuromuscular fatigue profiles between children, untrained adults and adult endurance athletes during repeated maximal muscle contractions. Eighteen prepubertal boys, 19 untrained men and 13 endurance male athletes performed 5-s maximal voluntary isometric knee extensor contractions (MVICs) interspersed with 5-s recovery until MVIC reached 60% of its initial value. Single and doublet magnetic stimulations were delivered to the femoral nerve to quantify the time course of potentiated twitch amplitude (Ttw,pot), high-frequency torque (T100Hz) and the low-to-high frequency torque ratio (T10Hz/T100Hz), i.e., indicators of peripheral fatigue. M-wave-normalized EMG amplitudes (EMG/M) and the maximal voluntary activation level (VA) were calculated to quantify central fatigue. Adults (15.9 ± 3.9 repetitions) performed fewer MVICs than children (40.4 ± 19.7) and endurance athletes (51.7 ± 19.6), however, no difference was observed between children and athletes (P = 0.13). Ttw,pot (∼52%, P < 0.001), T100Hz (∼39%, P < 0.001) and T10Hz/T100Hz (∼23%, P < 0.001) decreased only in adults. Similar decrements in vastus medialis and vastus lateralis EMG/M were observed in children and endurance athletes (range: 40–50%), and these were greater than in adults (∼15%). Whilst VA decreased more in children (-38.4 ± 22.5%, P < 0.001) than endurance athletes (-20.3 ± 10.1%, P < 0.001), it did not change in adults. Thus, children fatigued more slowly than adults and as much as endurance athletes. They developed less peripheral and more central fatigue than adults and, although central fatigue appeared somewhat higher in children than endurance athletes, both children and endurance athletes experienced greater decrements than adults. Therefore, children exhibit a more comparable neuromuscular fatigue profile to endurance athletes than adults

Composition of the essential oils of Origanum majorana and O. vulgare subsp hirtum growing wild in Turkey

The chemical composition of the essential oils isolated by hydrodistillation of the aerial parts of Origanum majorana L. and O. vulgare L. from Turkey has been examined by GC-MS. A total of 34 and 37 components were identified accounting for 97.80% and 98.61% of the oils of both O. vulgare and O. majorana, respectively. The oil of O. majorana contained carvacrol (43.12%), (E)-b-ocimene (13.03%), p-cymene (11.38%), linalool (10.07%) and thymol (4.46%) as main components. Major components of the O. vulgare oil were identified as carvacrol (48.38%), p-cymene (19.93%), y-terpinene (16.29%), p-caryophyllene oxyde (1.92%), p-caryophyllene (1.16%), linalool (1.58%) and myrcene (1.32%). It is shown that carvacrol was the dominant constituent of both oils. &nbsp

Aromatic Plants of Yugoslavia. I. Chemical Composition of Oils of Achillea millefolium L. ssp. pannonica (Scheele) Hayak, A. crithmifolia W. et K., A. serbica Nym. and A. tanacetifolia All.

We used GC/MS to determine the chemical composition of the essential oils of wild Achillea plants native to Yugoslavia: Achillea millefolium L. ssp. pannonica (Scheele) Hayak, A. crithmifolta W. et K., A. serbica Nym. and A. tanacetifolia All. Seventy-four components were identified. All four oils contained camphor (416%), l,8-cineole (623%) and bomeol (416%). In addition, artemisia ketone (4%) was found in A. crithmifolta, alpha-thujone (4.5%) in Achillea millefolium, yomogi alcohol and 2-pyrolidone were specific to A. serbica, and A. crithmifolia contained cis-chrysanthenol(l.4%) and large amounts of the corresponding acetate (23.4%)

The effect of harvest years on chemical composition of essential oil of pickling herb (Echinophora tenuifolia subsp. Sibthorpiana) leaves used as medicinal plant

The essential oils of leaves of Echinophora tenuifolia subsp. sibthorpiana (Apiaceae) growing wild in Middle Anatolia were obtained by hydrodistillation, and analysed by gas chromatography (GC) and gas chromatography-mass spectrometer (GC-MS). The major constituents were affected depend on harvest years. Methyl-eugenol, δ-3-carene and p-cymene were established as the major components of pickling herb leaves collected between 2003 and 2009. The main constituents of leave oil were methyl-eugenol (24.99% to 90.16%), δ-3-carene (2.57% to 34.80%) and p-cymene (1.23% to 9.81%) depending on the harvest years

Aromatic Plants of Yugoslavia. II. Chemical Composition of Essential Oils of Three Wild Achillea Species: A. clavenae L., A. collina Becker and A. lingulata W. et K.

Using GC/MS we examined the oils of Achillea clavenae, A. collina and A. lingulata. A. clavenae oil contained high levels of camphene (29.6%) and bornyl acetate (10.8%), A. collina was rich in 1,8-cineole (27.6%), chrysanthenone (8.5%) and camphor (9%), while A. lingulata contained borneol (20.3%) as the major constituent. Although these compounds occur in many varieties, their levels are characteristically high in these oils

CHEMICAL COMPOSITION OF ESSENTIAL OILS OF PHLOMIS GRANDIFLORA HS THOMPSON VAR. GRANDIFLORA FLOWERS AND LEAVES OF TURKISH ORIGIN

WOS: 000287093900009The essential oils of flower and leaves of Phlomis grandiflora H.S. Thompson var. grandiflora (Lamiaceae), endemic grown in Turkey, were obtained by hydrodistillation and analyzed by gas chromatography (GC) and GC-mass spectrometry. The yields of essential oil isolated by steam distillation from the flowers and leaves of Phlomis were 0.12 and 0.2% (w/w), respectively. Hydrodistillation of the dried flowers and leaves of Phlomis gave light-yellowish oils. Thirty-two components were identified in the flowers oil, which represented about 92.1% of the total composition of the oil. The major constituents of the flower essential oil were beta-eudesmol (61.48%), beta-curcumene (5.81%), E-beta-farnesene (2.35%), alpha-zingiberene (2.18%) and alpha-cedrene (1.94). Thirty-nine components were identified in the oil of leaves, making up 87.7% of the total composition. The major constituents of the essential oils of the leaves were beta-eudesmol (62.04%), beta-curcumene (3.43%), ar-curcumene (2.20%) and linalool (2.03%). In particular, both oils were characterized by a high content of beta-eudesmol. PRACTICAL APPLICATIONS Some species of Phlomis are used as tonic and stimulant in Turkey and against diseases of the respiratory tract or externally for the treatment of wounds. Also, many studies have shown various biological activities such as immunosuppressive free radical scavenging, antimicrobial and antimutagenic activities

,6%). The essential oil of A. senegalensis contains mostly linalool

Abstract: The aromatic vegetable secretions obtained by hydrodistillation from the leaves and fruit of Xylopia aethiopica and Annona senegalensis were studied by GC / MS. Different chemical compositions marked by significant proportions of some compounds are obtained. The main components of the essential oil of X. aethiopica are: b-pinene (8,5-46,1%), sabinene (9,8-41,8%), 1,8-cinéole (5,3-23,8%), a-thujene (5,3-12,6%), a-pinene (5,3%), g-terpinene (6,2%), trans-pinocarvéol (6,6-12,2%), cis-sabinol (6,7%), trans-verbénol (5,0%), pinocarvone (5,2%), terpinen-4-ol (9,2-30,8%), myrténol (9,1-13,7%), myrténal (7,4-17,1%), a-eudesmol (6,0%), élémol (5,1-11,9%) and vélérianol (7,7-10,6%). The essential oil of A. senegalensis contains mostly linalool (7,2-7,3%), (Z)-b-ocimene (6,0%), (E)-b-ocimene (6,6%), germacrene-D (6,5-14,2%), caryophyllene oxide (12,6%), intermédéol (6,5%), b-caryophyllene (5,3-8,8%), palmitic acid (6,6). The majority compounds constitutive of the two varieties of Annonaceae are not identical

Accelerated ageing effects on cucurbitea pepo seed oil

International audienceAccelerated ageing of curcubitea pepo seed oil was followed by simulation of UV (light) and ambiant oxygen actions held separately then simultaneously in order to know the effects of these parameters on this oil resistance to deterioraton. Nine withdrawals had undergone analyses by titrimetry supported by spectroscopic analyses notably MIR (Medium Infrared), DSC (Differential Scanning Calorimetry) and also a gas chromatography for the composition in FA. This study has showed that pumpkin seed oil displays a weak resistance to UV which results among other in a decrease of unsaponifiable compounds. Its oxidization takes place very quickly in the presence of ambiant oxygen. However the accumulated action of the two factors weakens to the highest degree pumpkin seed oil and this results in polymerization. It has also enabled us to show the link between the formation of recticulations in the oil matrix and variations at the level of the molecular structure of pumpkin seed oil