What's the difference between betulin and birch?

Betulin


Definition:

  • (n.) A substance of a resinous nature, obtained from the outer bark of the common European birch (Betula alba), or from the tar prepared therefrom; -- called also birch camphor.

Example Sentences:

  • (1) Based on spectroscopic data and chemical transformations, the structures of the new constituents were determined as 3-epi-betulinic acid 3-O-beta-D-glucopyranoside 28-O-[alpha-L-rhamnopyranosyl(1----4)-O-beta-D-glucopyranosyl(1----6)]-b eta- D-glucopyranoside and alpha-L-rhamnopyranosyl(1----4)-O-beta-D-glucopyranosyl(1----6)-beta-D- glucopyranose.
  • (2) The structures of the glycosides have been determined as 28-O-[alpha-L-rhamnopyranosyl(1----4)-O-beta-D-glucopyranosyl(1----6)-be ta-D- glucopyranosides of 3 alpha-hydroxy-lup-20(29)-ene-23,28-dioic acid, 3 alpha,11 alpha- dihydroxy-lup20(29)-ene-23,28-dioic acid and 3-epi-betulinic acid by spectroscopic data and chemical transformations.
  • (3) In addition to 3-epi-betulinic acid, three triterpene glycosides were isolated from leaves of Schefflera octophylla.
  • (4) On the basis of spectrometric analysis and physico-chemical constants they were identified as oleanolic acid, betulin and beta-sitosterol-D-glucoside respectively.
  • (5) A new triterpene saponin was isolated from the roots of Ampelozizyphus amazonicus together with the known 3-O-beta-D-glucopyranosyl-20-O-alpha-L-rhamnopyranosyljujubogenin and the known triterpenes melaleucic acid, 3 beta,27 alpha-dihydroxylup-20(29)-en-28 beta-oic acid, betulinic acid, betulin, lupeol.
  • (6) The constituents responsible for this activity were identified as uvaol, ursolic acid, and betulinic acid.
  • (7) From spectroscopic data and chemical transformations the structure of the new constituent was determined as 3-epi-betulinic acid 3-O-sulphate 28-O-[alpha-L-rhamnopyranosyl(1----4)-O-beta-D-glucopyranosyl (1----6)]-beta-D-glucopyranoside.
  • (8) A phytochemical investigation of Grewia bicolor gave the following results: the petroleum ether extract afforded beta-sitosterol and beta-sitosterol- and triterpene esters, and the triterpenes lupeol and betulin.
  • (9) megaphyllum gave (E)-betulin-3-p-coumarate [20] and (Z)-betulin-3-p-coumarate [21], both of which appear to be novel.
  • (10) beta-Sitosterol, betulinic acid, ursolic acid, 2alpha-hydroxyursolic acid, 2alpha,3alpha-dihydroxyurs-12-en-28-oic acid and a new triterpene acid, jacarandic acid, were also isolated.
  • (11) A new acetylated bidesmosidic triterpenoid saponin has been isolated from the leaves of Schefflera octophylla and structurally elucidated as 3-epi-betulinic acid 3-O-beta-D-6'-acetylglucopyranoside 28-[alpha-L-rhamnopyranosyl(1----4)-O-beta-D-glucopyranosyl(1----6)]-bet a-D-0-glucopyranoside [1].
  • (12) In addition, 5 mumol betulinic acid markedly inhibited the promoting effect of 2.5 micrograms TPA applied twice weekly on skin tumor formation in mice initiated with 50 micrograms of 7,12-dimethylbenz[a]anthracene, and 5 mumol of sitosterol caused slight suppression.

Birch


Definition:

  • (n.) A tree of several species, constituting the genus Betula; as, the white or common birch (B. alba) (also called silver birch and lady birch); the dwarf birch (B. glandulosa); the paper or canoe birch (B. papyracea); the yellow birch (B. lutea); the black or cherry birch (B. lenta).
  • (n.) The wood or timber of the birch.
  • (n.) A birch twig or birch twigs, used for flogging.
  • (n.) A birch-bark canoe.
  • (a.) Of or pertaining to the birch; birchen.
  • (v. t.) To whip with a birch rod or twig; to flog.

Example Sentences:

  • (1) Sixty patients with seasonal allergic rhinitis due to birch pollen were enrolled in an open, randomized parallel group study.
  • (2) If the majority of relevant tree pollens are to be included in a diagnostic or therapeutic programme in Western Sweden it should contain birch, alder, hazel, beech and bog-myrtle allergens.
  • (3) Bet v I, the major birch pollen allergen, could be extracted easily from pollen, and in low amounts from callus and leaves.
  • (4) In the case of initially negative tests with positive second and third SPTs the incidence ranged between 3.2% (cat dander) and 4.3% (birch pollen) per year.
  • (5) The sera that did not detect the 15 kD bands in celery failed to react with both the 15 kD mugwort component and the 14 and 16 kD birch components.
  • (6) In previous experiments it was found that birch, beech, alder, hazel and oak are pollens with importance in pathogenesis of early pollinosis in our region of Central Europe.
  • (7) We conclude that in children with birch pollinosis oral immunotherapy with high doses of a biologically potent preparation in enteric-coated capsules is effective, easy to perform, economic and safe.
  • (8) The patients selected for study were subjects with a combined inhalant allergy to birch pollen and an oral allergy to apple fruit.
  • (9) In the same area, the birch pollen load was 2.8 times higher, which caused specific IgE in 10.5% as against 3.5% of the other group (P less than 0.01) as well as positive skin prick test in 9.0% as against 3.5% (P less than 0.05).
  • (10) Moreover, a major pollen allergen in birch (BetvI) has a 44% identity with PvPR1 proteins.
  • (11) It appears that screening for an IgE-mediated allergy can be performed with a limited number of skin tests (rye grass, timothy, birch, house dust mite and cat).
  • (12) RAST investigations on the sera of 27 patients suffering from celery allergy showed specific IgE to mugwort and birch in 15 cases; sensitization to mugwort or birch alone only occurred in 5 and 7 cases, respectively.
  • (13) Nine patients with strictly seasonal allergic rhinitis caused by birch pollen and five healthy nonatopic control subjects participated in the present study, which started 1 wk before the birch pollen season and continued throughout the entire pollen season.
  • (14) Of all positive RAST reactions observed, 74% were against the following allergens: horse and cat epithelium, birch and timothy pollen, and house dust.
  • (15) Thus 98% of atopic patients with seasonal allergic rhinitis were detected by an allergen panel consisting of timothy, birch and mugwort.
  • (16) The sera selected were positive in the RAST for both birch pollen and fruits.
  • (17) Cross-incubations: birch pollen incubated with antibodies against hazel (Ab-CA), or alder (Ab-AI), showed various intensities of gold labelling for each of the three species.
  • (18) We have studied the influence of substance P (SP) on the proliferative response of concanavalin A (ConA)-activated peripheral blood lymphocytes from 16 birch pollen-allergic patients, sampled before and during the pollen season, and from 15 normal individuals.
  • (19) The beavers have felled most of the bankside birch, sycamore and other trees they like to eat and use for their dams.
  • (20) Nine asthmatic patients with an allergy to birch or timothy underwent bronchial allergen provocations on three different trial days, with intervals of 2 to 5 wk.

Words possibly related to "betulin"

Words possibly related to "birch"