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A compound consisting of hydrogen and chlorine. Hydrochloric acid is secreted in the stomach and is a major component of gastric juice. A clear, colorless, fuming, poisonous, highly acidic aqueous solution of hydrogen chloride, HCl, used as a chemical intermediate and in petroleum production, ore reduction, food processing, pickling, and metal cleaning. It is found in the stomach in dilute form. HCI is Hydrogen (H), Carbon (C) and Iodine (I). Therefore, you have three elements in one molecule of HCI. Although, HCI is not balanced, so, that would actually be an ion, with negative charge.
Se non se indica outra cousa, os datos están tomados en condicións estándar de 25 °C e 100 kPa.
Referencias
O ácido elaídico ou ácido trans-9-octadecenoico [1][2] é un ácido graxo insaturado trans, que é a principal graxa trans que se encontra nos aceites vexetais hidroxenados e aparece en pequenas cantidades no leite caprino e bovino (aproximadamente o 0,1% dos ácidos graxos que conteñen) [3] e nalgunhas carnes. É un isómero xeométrico do ácido oleico, sendo este último a forma cis. O nome da reacción chamada elaidinización procede deste ácido ; dita reacción consiste en alterar a orientación da configuración en torno aos dobres enlaces de cis a trans, o que incrementa o punto de fusión e a duración das graxas.
O ácido elaídico incrementa a actividade da proteína transferente de colesteriléster (CETP), a cal á súa vez eleva a cantidade de colesterol VLDL e diminúe a do colesterol HDL, o que pode favorecer a aterosclerose.[4]
Utilízase comercialmente na preparación de oleatos e locións, e como solvente farmacéutico.[5]
Notas
CHEBI
ChemSpider - Elaidic acid
Alonso L, Fontecha J, Lozada L, Fraga MJ, Juárez M (1999). "Fatty acid composition of caprine milk: major, branched-chain, and trans fatty acids". J. Dairy Sci.82 (5): 87884. doi:10.3168/jds.S0022-0302(99)75306-3. PMID 10342226.
Abbey M, Nestel PJ (1994). "Plasma cholesteryl ester transfer protein activity is increased when trans-elaidic acid is substituted for cis-oleic acid in the diet". Atherosclerosis106 (1): 99107. doi:10.1016/0021-9150(94)90086-8. PMID 8018112.
PubChem compound - Elaidic acid
Véxase tamén
Ligazóns externas
Sommerfeld M. Trans unsaturated fatty acids in natural products and processed foods. Prog Lipid Res. 1983;22(3):221-33. PMID 6356151. [1]. Graxas trans na natureza e nos alimentos.
Limestone A noncombustible solid characteristic of sedimentary rock. It consists primarily of calcium carbonate))[TOP]
1317-65-3
215-665-4
Sorbitan oleate C24H44O6[TOP]
1338-43-8
216-472-8
Calcium distearate, pure C18H36O2.1/2Ca[TOP]
1592-23-0
231-147-0
Argon Ar[TOP]
7440-37-1
231-153-3
Carbon C[TOP]
7440-44-0
231-783-9
Nitrogen N2[TOP]
7727-37-9
231-791-2
Water, distilled, conductivity or of similar purity H2O[TOP]
7732-18-5
231-955-3
Graphite C [TOP]
7782-42-5
232-273-9
Sunflower oil Extractives and their physically modified derivatives. It consists primarily of the glycerides of the fatty acids linoleic, and oleic. (Helianthus annuus, Compositae).[TOP]
8001-21-6
232-274-4
Soybean oil Extractives and their physically modified derivatives. It consists primarily of the glycerides of the fatty acids linoleic, oleic, palmitic and stearic (Soja hispida, Leguminosae).[TOP]
8001-22-7
232-276-5
Safflower oil Extractives and their physically modified derivatives. It consists primarily of the glycerides of the fatty acid linoleic (Carthamus tinctorius, Compositae).[TOP]
8001-23-8
232-278-6
Linseed oil Extractives and their physically modified derivatives. It consists primarily of the glycerides of the fatty acids linoleic, linolenic and oleic (Linum usitatissimum, Linaceae).[TOP]
8001-26-1
232-281-2
Corn oil Extractives and their physically modified derivatives. It consists primarily of the glycerides of the fatty acids linoleic, oleic, palmitic and stearic. (Zea mays, Gramineae).[TOP]
8001-30-7
232-293-8
Castor Oil Extractives and their physically modified derivatives. It consists primarily of the glycerides of the fatty acid ricinoleic (Ricinus communis, Euphorbiaceae).[TOP]
8001-79-4
232-299-0
Rape oil Extractives and their physically modified derivatives. It consists primarily of the glycerides of the fatty acids erucic, linoleic and oleic (Brassica napus, Cruciferae).[TOP]
8002-13-9
232-307-2
Lecithins The complex combination of diglycerides of fatty acids linked to the choline ester of phosphoric acid.[TOP]
8002-43-5
232-436-4
Syrups, hydrolyzed starch A complex combination obtained by the hydrolysis of cornstarch by the action of acids or enzymes. It consists primarily of d-glucose, maltose and maltodextrins.[TOP]
8029-43-4
232-442-7
Tallow, hydrogenated[TOP]
8030-12-4
232-675-4
Dextrin[TOP]
9004-53-9
232-679-6
Starch High-polymeric carbohydrate material usually derived form cereal grains such as corn, wheat and sorghum, and from roots and tubers such as potatoes and tapioca. Includes starch which has been pregelatinised by heating in the presence of water.[TOP]
9005-25-8
232-940-4
Maltodextrin[TOP]
9050-36-6
234-328-2
Vitamin A[TOP]
11103-57-4
238-976-7
Sodium D-gluconate C6H12O7.xNa[TOP]
14906-97-9
248-027-9
D-glucitol monostearate C24H48O7[TOP]
26836-47-5
262-988-1
Fatty acids, coco, Me esters[TOP]
61788-59-8
262-989-7
Fatty acids, tallow, Me esters[TOP]
61788-61-2
263-060-9
Fatty acids, castor-oil[TOP]
61789-44-4
263-129-3
Fatty acids, tallow[TOP]
61790-37-2
265-995-8
Cellulose Pulp[TOP]
65996-61-4
266-925-9
Fatty acids, C12-18 This substance is identified by SDA Substance Name: C12-C18 alkyl carboxylic acid and SDA Reporting Number: 16-005-00.[TOP]
67701-01-3
266-928-5
Fatty acids C16-18 This substance is identified by SDA Substance Name: C16-C18 alkyl carboxylic acid and SDA Reporting Number: 19-005-00.[TOP]
67701-03-5
266-929-0
Fatty acids, C8-18 and C18-unsaturated. This substance is identified by SDA Substance Name: C8-C18 and C18 unsaturated alkyl carboxylic acid and SDA Reporting Number: 01-005-00.[TOP]
67701-05-7
266-930-6
Fatty acids, C14-18 and C16-18-unsaturated. This substance is identified by SDA Substance Name: C14-C18 and C16-C18 unsaturated alkyl carboxylic acid and SDA Reporting Number: 04-005-00[TOP]
67701-06-8
266-932-7
Fatty acids, C16-C18 and C18-unsaturated. This substance is identified by SDA Substance Name: C16-C18 and C18 unsaturated alkyl carboxylic acid and SDA Reporting Number: 11-005-00[TOP]
67701-08-0
266-948-4
Glycerides, C16-18 and C18-unsaturated. This substance is identified by SDA Substance Name: C16-C18 and C18 unsaturated trialkyl glyceride and SDA Reporting Number: 11-001-00.[TOP]
67701-30-8
267-007-0
Fatty acids, C14-18 and C16-18-unsaturated., Me esters This substance is identified by SDA Substance Name: C14-C18 and C16-C18 unsaturated alkyl carboxylic acid methyl ester and SDA Reporting Number: 04-010-00.[TOP]
67762-26-9
267-013-3
Fatty acids, C6-12 This substance is identified by SDA Substance Name: C6-C12 alkyl carboxylic acid and SDA Reporting Number: 13-005-00.[TOP]
67762-36-1
268-099-5
Fatty acids, C14-22 and C16-22 unsaturated. This substance is identified by SDA Substance Name: C14-C22 and C16-C22 unsaturated alkyl carboxylic acid and SDA Reporting Number: 07-005-00[TOP]
68002-85-7
268-616-4
Syrups, corn, dehydrated[TOP]
68131-37-3
269-657-0
Fatty acids, soya[TOP]
68308-53-2
269-658-6
Glycerides, tallow mono-, di- and tri-, hydrogenated[TOP]
68308-54-3
270-298-7
Fatty acids, C14-22[TOP]
68424-37-3
270-304-8
Fatty acids, linseed-oil[TOP]
68424-45-3
270-312-1
Glycerides, C16-18 and C18-unsaturated. mono- and di- This substance is identified by SDA Substance Name: C16-C18 and C18 unsaturated alkyl and C16-C18 and C18 unsaturated dialkyl glyceride and SDA Reporting Number: 11-002-00.[TOP]
source d'énergie dans l'organisme : exercice de sciences physiques de seconde - 256183
Inscription / Connexion Nouveau Sujet
Bonjour, je suis perdu quelqu'un pourrai m'aider dans man DM de chimie ?
Posté par sassoudm chimie 15-04-12 à 14:16
la question est:
les lipides constituent la deuxieme source d'énergie majeure. Ces lipides sont hydrolysés, c'est à dire coupés par l'eau, puis transformés en acides gras. L'un d'eux est l'acide oléique, de formule C18H34O2.
1) écrire l'équation de combustion complête de l'acide oléique.
2)La combustion d'une mole d'acide oléique libère une énergie égale à 11120kj. Quelle est l'énergie libérés par la combustion de 6g d'acide oléique?
Données: m(c)= 12g.mol-1 ; m(o)=16g.mol-1 ; m(h)=1g.mol-1
Posté par sassoure : mécanique cage d'ascenseur 15-04-12 à 14:18
Pourrais tu m'aider aussi efpe ?
*** message déplacé ***
Posté par efpere : source d'énergie dans l'organisme 15-04-12 à 14:34
salut
qui dit combustion complète dit oxygène comme réactif, et eau et dioxyde de carbone comme produit :
C18H34O2 + O2 -> CO2 + H2O
il faut maintenant équilibrer
2 C18H34O2 + 51 O2 -> 36 CO2 + 34 H2O
ça va jusque là ?
Posté par sassoure : source d'énergie dans l'organisme 15-04-12 à 14:38
merci d'avoir répondu oui jusqu'à la je comprends
Posté par sassoure : source d'énergie dans l'organisme 15-04-12 à 14:46
mais je ne comprends pas ce qu'on me demande à la question 2. je ne sais pas ce que signifie 'kj'
Posté par efpere : source d'énergie dans l'organisme 15-04-12 à 15:19
kJ signifie kilo Joule, c'est à dire 1000 joules
il faut commencer par calculer le nombre de moles contenus dans 6g d'acide oléique
Posté par sassoure : source d'énergie dans l'organisme 15-04-12 à 15:31
Donc il faut multiplier la masse molaire de l'acide oléique par 6 ? ensuite multiplier par 1000 joules ?
Posté par efpere : source d'énergie dans l'organisme 15-04-12 à 15:36
Non
si je te donne m(c)= 12g.mol-1 ; m(o)=16g.mol-1 ; m(h)=1g.mol-1 et la formule C18H34O2 de l'acide oléique, tu es capable de me donner sa masse molaire ?
Posté par sassoure : source d'énergie dans l'organisme 15-04-12 à 15:41
oui on fait C*18+O*2+H*34
et le résultat sera en g.mol-1 non ?
Posté par efpere : source d'énergie dans l'organisme 15-04-12 à 15:48
oui tout à fait
ça te donne donc la masse molaire de l'acide oléique. A partir de là, tu es capable de me donner le nombre de moles correspondant à 6g
Posté par sassoure : source d'énergie dans l'organisme 15-04-12 à 16:02
ah je crois avoir compris il faut donc appliquer la formule n=m/M ; donc 6 divisé par la masse molaire ?
Posté par efpere : source d'énergie dans l'organisme 15-04-12 à 16:03
Posté par sassoure : source d'énergie dans l'organisme 15-04-12 à 16:04
mais à quoi sert 11120kj ?
Posté par efpere : source d'énergie dans l'organisme 15-04-12 à 16:05
on a maintenant la quantité de matière d'acide oléique
et on te dit : La combustion d'une mole d'acide oléique libère une énergie égale à 11120kj
donc tu dois faire quoi à ton avis ?
Posté par sassoure : source d'énergie dans l'organisme 15-04-12 à 16:06
je dois multiplier la quatité de matiere d'acide oléique par 11120kj ?
Posté par efpere : source d'énergie dans l'organisme 15-04-12 à 16:10
Posté par sassoure : source d'énergie dans l'organisme 15-04-12 à 16:11
merci beaucoup pour votre aide
Posté par efpere : source d'énergie dans l'organisme 15-04-12 à 16:12
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Acides
gras, triglycérides. Exercice 1
(Réponse).
Déterminer la formule brute et indiquer le nom d'un acide gras de
1/ masse molaire égale à 280 g et 2/ un pourcentage en oxygène
égal à 11,51% .Acides
gras, triglycérides. Exercice 2 (Réponse).
Chercher la formule brute et indiquer le nom d'un acide gras saturé
dans les deux situations suivantes:
-
Acide gras de masse molaire égale à 284 g.
- Acide gras dont le pourcentage en oxygène est 12,5%.
Acides
gras, triglycérides. Exercice 3,
(Réponse).
Représenter le tronc commun à tous les triglycérides.
et donner la représentation semi-développée des trois
triglycérides suivants:
Ecrire
la formule brute et calculer la masse molaire des trois triglycérides
ci dessus.
Acides
gras, triglycérides. Exercice 4,
(Réponse).
Un triglycéride homogène a une masse molaire égale
à 890 g. Déterminer la nature (nom et formule brute) de cet
acide gras.
Acides
gras, triglycérides. Exercice 5, (Réponse).
Un triglycéride homogène contient 11,91% d'oxygène.
Déterminer la formule et le nom de cet cet acide gras.
Acides
gras, triglycérides. Exercice 6, (Réponse)
-
Calculer l'indice d'iode de la trioléine. L'acide oléique
est l'acide octadéc 9 ène oïque
-
Une huile végétale contient 30% de trioléine, 60%
de tripalmitine et 10% de tristéarine. Calculer son indice d'iode
sachant que l'acide palmitique est l'acide hexadécanoïque
et l'acide stéarique est l'acide octadécanoïque.
Acides
gras, triglycérides. Exercice 7, (Réponse).
Un homogénat tissulaire est soumis à une chromatographie
sur couche mince de gel de silice utilisant une phase mobile constituée
d'un mélange d'hexane-éther éthylique-acide acétique.
Parmi les lipides identifiés sur le chromatogramme on note des acides
gras, Monoglycérides, Diglycérides, Triglycérides,
Cholestérol libre, Cholestérol estérifié
et Phospholipides. Shématiser les résultats de la séparation
chromatographique.
-
a/ Ecrire la structure développée du lipide OLP.
- b/ Calculer son indice de saponification et son indice d'iode.
- c/ Que donne l'hydrolyse de OLP par la phospholipase C ? On
donne: KOH = 56, H3PO4 = 98 et I=127.
Acides
gras, triglycérides. Exercice 9, (Réponse).
Parmi ces lipides (A, B, C, D) choisir celui qui présente l'indice
d'iode le plus élevé.
RéponsesRéponse
1 (Exercice
1)
Réponse 2 (Exercice
2)
Réponses
3 + 4 (Exercices
3+4)
Recherche
rapide dans ce site et les sites liés de l'auteur (Fr,
Ar, Eng) -
:
Glossaire
des sciences de la vie, trilingue (Fr, Ar, Eng) + Préparations
Examens et contrôles S1, S2, S3 + DVD introductinon
MOOC:
Réponses
7 (Exercices
7).
Les différents lipides seront séparés selon le critère
de polarité. Les lipides les plus apolaires migreront rapidement.
Les phospholipides
très polaires, ne migrent plus (restent au point de départ,
Rf = 0). Les Monoglycérides polaires (deux OH), migrent
peu (migration du bas vers le haut). Les Diglycérides et le Cholestérol
libre migreront au milieu, au dessus des Monoglycérides, car
ils sont moyennement polaires. Les acides gras très légèrement
polaires migreront au milieu de la plaque, au dessus des Diglycérides.
Etant apolaires, les Triglycérides
migreront presque à l'extrémité de la plaque. Etant
très apolaires, les esters du Cholestérol migreront
avec le front du solvant. Voir le TP
chromatographie sur couche mince des lipides (texte et vidéo).
Réponses
8 (Exercices
8).
-
a/ Structure développée du lipide OLP:
-b/
Calcul de l'indice de saponification et de l'indice d'iode du lipide OLP
:
1-
Le poids moleculaire du lipide OLP : C18H34O2 = 282, C18H32O2 = 280, 2
x Glycerol = 92x2 = 184, H3PO4 = 98, 4xH2O = 72.
PM
= (282+280+184+98) - 72 = 772.
Indice de saponification (avec 2 acides
gras rentrant dans la saponification): Is = (m KOH*2
/ PM)x 10^3. Donc, Is = 57*2*1000/772 = 147,66 mg/g de MG.
Indice d'iode : Ii = (mI2*delta/PM)* 100. Donc Ii= 127*2*3*100/772
= 98,7 g/100g de MG
c-
Le resultat de l'hydrolyse de ce lipide par la phospholipase C : détachement
du phosphoglycerol du lipide OLP.
Réponses
9 (Exercices
9).
C'est l'acide gras (D) qui offre le meilleur rapport 'nombre de liaisons
doubles/nombre de carbones' qui donnera l'indice d'iode le plus élevé.Vidéos(Vidéos
sur DVD avec explications dans le livre 'Science de la vie-Biochimie', Baaziz
2012, édité pour la préparation de la transition Secondaire-Supérieur
(Ar --> Fr). Soutenir cette action par l'acquisition
de cet ouvrage et en même temps appuyer la continuité des
services gratuits rendus par le site takween.com au profits de tous les
étudiants)
-
Acides gras. Structure (narration en Arabe, titrage en Fr):
-
Triglycérides, Phospholipides et Stéroïdes (narration
en Arabe, titrage en Fr):
Seaweeds are potential renewable resources in the marine environment. The antibacterial activity of Jania rubens, Corallina mediterranea and Pterocladia capillacea were analyzed against human pathogenic bacteria. The present study was performed to investigate the phytochemical constituents of seaweeds, such as alkaloids, flavonoids, steroids, terpenoids and phlobatannins. In this study, we estimated phenols, flavonoids, tannins, pigments and mineral contents and determined the hydrogen peroxide scavenging activity, reducing power and total antioxidant activity of various extracts of selected seaweeds. Phytochemicals were extracted from the three seaweeds using various solvents, such as methanol, ethanol, acetone and chloroform. Among the various extracts, the methanolic extract was found to have the highest reducing power and total antioxidant capacity. We evaluated the seaweeds against Vibrio fluvialis, and Pterocladia capillacea was the most effective at controlling its growth. The highest zone of inhibition was recorded in the methanol extract. The chemical constituents of the seaweeds were characterized by GCMS, which showed that they contain organic compounds, such as 1,2-benzenedicarboxylic acid.
Keywords
Marine environment;
Photosynthetic pigments;
Biochemical composition;
Mineral
1. Introduction
Since ancient times, macroscopic marine algae has been closely associated with human life and has been exhaustively used in numerous ways as a source of food, feed, fertilizer and medicine, and chiefly used for economically important phycocolloids [1] and [2]. Marine algae contain more than 60 trace elements in a concentration much higher than in terrestrial plants. They also contain protein, iodine, bromine, vitamins and substances of stimulatory and antibiotic nature. The phytochemicals from marine algae are extensively used in various industries such as food, confectionary, textile, pharmaceutical, dairy and paper, mostly as gelling, stabilizing and thickening agents. Seaweeds or marine macro algae are renewable living resources that are also used as food, feed and fertilizer in many parts of the world.
In addition to vitamins and minerals, seaweeds are also potentially good sources of proteins, polysaccharides and fibres [3] and [4]. Recently, Hebsibah and Dhana Rajan [5] studied variations in the chemical constituents of the marine red alga Hypnea valentiae from the Tuticorin and Mandapam Coasts. Dinesh et al. [6] studied the nutritive properties of 20 species of seaweeds from the Gulf of Mannar. Seenivasan et al. [7] screened the antibacterial activity of extracts of marine algae representing Chlorophyta and Rhodophyta collected from the Vishakapatnaam Coast against two pathogens and also tested their ability to inactivate the enzyme penicillinase in vitro. Extracts of marine algae were reported to exhibit antibacterial activity [8] and [9]. Vanitha et al. [10] reported the antibacterial action of nine seaweeds collected from the Kanyakumari Coast against human upper respiratory tract pathogens, which include both gram-positive and gram-negative bacteria.
Kandhasamy and Arunachalam [11] determined the in vitro antibacterial properties of the seaweeds Caulerpa racemosa, Ulva lactuca, Gracilaria foliifera, Hypnea musciformis, Sargassum tenerrimum, S. myriocystem and Padina tetrastromatica collected from Koodankullam, and Tirunelveli against gram-negative and gram-positive pathogenic bacteria. Anitha et al. [12] determined the antibacterial activity of methanol, diethyl ether, acetone and dichloromethane extracts of Padina Boergesenii collected against 10 human pathogenic bacteria. Marine resources are an unmatched reservoir of biologically active natural products, many of which exhibit structural features that have not been found in terrestrial organisms [13]. There are numerous reports on compounds derived from macro algae with broad ranges of biological activities, such as the antimicrobial, antiviral, anti-tumour, anti-inflammatory, and neurotoxic [14]. The present study was performed with three marine seaweeds: Jania rubens, Corallina mediterranea and Pterocladia capillacea red algae. The study was performed with the following objectives: (1) To investigate the preliminary phytochemical constituents present in the three seaweeds. (2) To estimate the biochemical composition and photosynthetic pigments of the selected seaweeds. (3) To analyze the mineral composition of the three seaweeds. (4) To evaluate the antibacterial activity of the three seaweeds. (5) To reveal the chemical constituents in the three seaweeds using GCMS analysis.
2. Materials and methods
2.1. Collection and identification of seaweeds
The studied algal species were collected from the coastal area of Abu-Qir Alexandria North Egypt. Algal samples were cleaned of epiphytes, and necrotic parts were removed. Then, cleaned samples were rinsed with sterile water to remove any associated debris. The cleaned fresh materials were shade air-dried and ground into fine powder, as described by Gonzalez del Val et al. [15]. The samples were identified as, Jania rubens (Linnaeus), Corallina mediterranea (J. Agardh) and Pterocladia capillacea (Gmelin).
2.2. Preparation of seaweed extracts
Ten grams of powdered samples were extracted with 50 ml of solvents, such as methanol, ethanol, acetone and chloroform. The samples were kept in the dark for 72 h with intermittent shaking. After incubation, the solution was filtered through filter paper, and the filtrate was collected (crude extracts) and stored in the refrigerator until further use.
2.3. Gas chromatography and mass spectrometry analysis
Gas chromatographymass spectrometry (GCMS) analysis was performed using an Agilent GC-MC-5975C with a TripleAxis Detector equipped with an auto sampler. The GC column used was fused with silica capillary column (length 30 m × diameter 0.25 mm × film thickness 0.25 m) with helium at 1.51 ml for 1 min as a carrier gas. The mass spectrometer was operated in the electron impact (El) mode at 70 eV in the scan range of 40700 m/z. The split ratio was adjusted to 1:10, and the injected volume was 1 l. The injector temperature was 250 °C, and the oven temperature was kept at 70 °C for 3 min, rose to 250 °C at 14 °C min1 (total run time 41 min). Peak identification of crude seaweed extracts were performed by comparison with retention times of standards, and the mass spectra obtained were compared with those available in NIST libraries (NIST 11 Mass Spectral Library, 2011 version) with an acceptance criterion of a match above a critical factor of 80% according to Musharraf et al. [16].
2.4. Estimation of flavonoid content
Total flavonoid content was determined according to the method of Chang et al. [17]. A one-ml aliquot of each extract was mixed with 0.1 ml of 10% aluminium chloride and 0.1 ml of 1 M potassium acetate. Methanol (2.8 ml) was added and kept at room temperature for 30 min. The absorbance of the reaction mixture was measured at 415 nm. The flavonoid content was expressed in mg/g, and Quercetin was used as a standard compound.
2.5. Estimation of tannin content
Total tannin content was determined according to the method of Julkunen-Titto [18]. Briefly, 50 l of seaweed extract was mixed with 1.5 ml of 40% vanillin (prepared with methanol), and then 750 l of HCl was added. The solution was shaken vigorously and left to stand at room temperature for 20 min in darkness. Absorbance against a blank was read at 500 nm. Catechin was used as standard.
2.6. Estimation of phenol content
The total phenol content was measured using the FolinCiocalteu method of Taga et al. [19]. Extract (100 l) was mixed with 2 ml of 2% Na2CO3 and allowed to stand for 2 min at room temperature. Then, 100 l of 50% FolinCiocalteu phenol reagent was added. After incubation for 30 min at room temperature in darkness, the absorbance was read at 720 nm. The total phenol content of samples was expressed as mg gallic acid per gram.
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references
Petroselinic acid is a fatty acid that occurs naturally in several animal and vegetable fats and oils. It is a white powder and is commercially available.[1] In chemical terms, petroselinic acid is classified as a monounsaturated omega-12 fatty acid, abbreviated with a lipid number of 18:1 cis-6. It has the formula CH3(CH2)10CH=CH(CH2)4COOH. The term "petroselinic" means related to, or derived from, oil of Petroselinum, parsley. Petroselinic acid is an positional isomer of oleic acid.
Occurrence
Petroselinic was first isolated from parsley seed oil in 1909.[2] Petroselinic acid occurs in high amounts in plants in Apiaceae, Araliaceae,[3]Griselinia (Griseliniaceae)[4] and in Garryaceae.[5] In Picramniaceae, petroselinic acid is accompanied by tariric acid.[6] In addition, petroselinic acid has been found in minor amounts in several fats of plant and animal origin, including in human sources.[7]
The occurrence of petroselinic acid as the major fatty acid is used in chemosystematics as a proof of a close relationship of several families within the Apiales as well as within the Garryales.[8] Besides petroselinic acid, oleic acid has been shown to be present in all cases examined.
Production and chemical behavior
Fatty acids mostly occur as their esters, commonly the triglycerides, which are the greasy materials in many natural oils. Via the process of saponification, the fatty acids can be obtained.
The trans isomer of petroselinic acid is called petroselaidic acid.
In chemical analysis, petroselinic acid can be separated from other fatty acids by gas chromatography of methyl esters; additionally, a separation of unsaturated isomers is possible by argentation thin-layer chromatography.[9]
Uses
Petroselinic acid can be used in cosmetics.[10]
References
^ChemicalBook [1]
^E. Vongerichten and A. Köhler (1909). "Über Petroselinsäure, eine neue Ölsäure". Chem. Ber.42 (2): 1638. doi:10.1002/cber.19090420232.
^F. C. Palazzo and A. Tamburello (1914). "Sopra l'acido iso-oleico dei semi di edera". Atti della Accademia Nazionale die Lincei. Rendiconti. Classe di science fisiche, matematiche e naturali5 (23): 352.
^B. Breuer, T. Stuhlfauth, H. Fock and H. Huber (1987). "Fatty acids of some cornaceae, hydrangeaceae, aquifoliaceae, hamamelidaceae and styracaceae". Phytochemistry26 (5): 14411445. doi:10.1016/S0031-9422(00)81830-0.CS1 maint: Multiple names: authors list (link)
^R. Kleiman and G. Spencer (1982). "Search for new industrial oils". J. A. O. S. C.59: 29. doi:10.1007/BF02670064.
^M. Tsujimoto and H. Koyanagi (1933). "On Nigaki Oil". Bull. Chem. Soc. Japan8 (5): 161. doi:10.1246/bcsj.8.161.
^Thomas Stuhlfauth (1984). "Chemosystematische Untersuchungen zur Fettsäurezusammensetzung von Frucht- und Samenölen der Pittosporaceen sowie einiger Arten der Rutales und Araliales, dissertation". University of Kaiserslautern, Germany: 5255.
^T. Stuhlfauth, H. Fock, H. Huber and. K. Klug (1985). "The distribution of fatty acids including petroselinic and tariric acids in the fruit and seed oils of the pittosporaceae, araliaceae, umbelliferae, simaroubaceae and rutaceae". Biochemical systematics and ecology13 (4): 447453. doi:10.1016/0305-1978(85)90091-2.CS1 maint: Multiple names: authors list (link)
^B. Breuer, T. Stuhlfauth and H. P. Fock (1987). "Separation of fatty acids or methyl esters including positional and geometric isomers by alumina argentation thin-layer chromatography". J. Of Chromatogr. Science25 (7): 302306. doi:10.1093/chromsci/25.7.302. PMID 3611285.
^Kosmetische Verwendung von Petroselinsäure, Patent DE69927466T3
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Alkenoic acids
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