Pharmacologically Active Ingredients VI

Aloctin A, Active Substance Of Aloe Arborescens Miller As An Immunomodulator Imanishi K Department Of Microbiology & Immunology, Tokyo Women’s Medical College Phytotherapy Research (1993) Vol 7, No. Special issue, pp. S20-S22. 15 ref. Aloctin A (Alo A), an active substance isolated from the leaves of A. arborescens, has many biological and pharmacological activities, such as mitogenic activity for lymphocytes, binding of human alpha 2-macroglobulin, complement activation via the alternative pathway, anti-inflammatory activity, anti-ulcer activity and antineoplastic activity. Alo A exhibited immunomodulatory activities on the immune responses of murine and human lymphoid cells in vivo and in vitro. Purification & Characterization Of Two Lectins From Aloe Arborescens Mill. Suzuki I; Saito H; Inoue S; Migita S; Takahashi T J Biochem (Tokyo) 85(1):163-71 1979 Jan Two lectins have been isolated from leaves of Aloe arborescens Mill by salt precipitation, pH-dependent fractionation and gel filtration. One lectin (P-2) has a molecular weight of approximately 18,000, consists of two subunits (alphabeta) and contains more than 18% by weight of neutral carbohydrate. The smaller subunit (alpha) has a molecular weight of approximately 7,500 and the larger subunit (beta) a molecular weight of approximately 10,500. The other lectin (S-1) has a molecular weight of approximately 24,000, consists of two subunits (gamma2) with a molecular weight of approximately 12,000 and contains more than 50% by weight of neutral carbohydrate. An interesting feature of the amino acid compositions of these lectins is the high proportion of acidic amino acids, such as aspartic acid and glutamic acid, and the low proportion of methionine and histidine. S-1 has a strong hemagglutinating activity. On the other hand, P-2 has not only hemagglutinating activity but also mitogenic activity on lymphocytes, precipitate-forming reactivity with serum proteins, one of which is alpha2-macroglobulin, and complement C3 activating activity via the alternate pathway. Anti-Inflammatory C-Glucosyl Chromone From Aloe Barbadensis Hutter JA; Salman M; Stavinoha WB; Satsangi N; Williams RF; Streeper RT; Weintraub ST Department Of Pharmacology, Research Imaging Center, University Of Texas Health Science Center J Nat Prod Vol 59, ISS 5, 1996, P541-3 A new anti-inflammatory agent identified as 8-[C-beta-D-[2-O-(E)-cinnamoyl]glucopyranosyl]-2- [(R)-2-hydroxypropyl]-7-methoxy-5-methylchromone (1) has been isolated from Aloe barbadensis Miller. At a dose of 200 microg/mouse ear, 1 exhibited topical anti-inflammatory activity equivalent to 200 microg/ear of hydrocortisone. There was no reduction in thymus weight caused by treatment with 1 for any of the doses tested, while 200 microg/ear of hydrocortisone resulted in a 50% decrease in thymus weight. Biotransformation Of Aloenin, A Bitter Glucoside Constituent Of Aloe Arborescens By Rats Hirata T; Sakano S; Suga T Experientia 37(12):1252-3 1981 Dec 15 Aloenin has been established to be 4-methoxy-6-(2-beta-D-glucopyranosyloxy-4-hydroxy-6-methylphenyl)-2-pyrone; it shows an inhibitory activity for gastric juice secretion. Rats metabolized it to 4-methoxy-6-(2,4-dihydroxy-6-methylphenyl)-2-pyrone, 2,5-dimethyl-7-hydroxychromone and glucose, which were excreted in the feces and the urine. The distribution of the radioactivity originating from 14C-labeled aloenin was studied. The tracer found in the kidney and the liver reached 60% of the amount administered 24 h after feeding and decreased rapidly in the next 24 h. Biologically Active Constituents Of Leaves & Roots Of Aloe Arborescens Var. Natalensis Hirata T; Suga T Z Naturforsch [C], 32(9-10):731-4 1977 Sep-Oct Several biologically active substances, such as aloenin (1), magnesium lactate, Aloe-emodin (4), barbaloin (5), and succinic acid, were found to be contained in the leaf juice of Aloe arborescens Mill. var. natalensis Berger, which has widely been used in domestic medicines. Aloenin (1) and magnesium lactate were elucidated to exhibit an inhibitory action on the gastric juice secretion of rats. Various constituents other than the above bioactive substances were found in the leaves and the roots of the plant.