Gunnar Samuelsson

Inventory of plants used in traditional medicine in Tanzania. I. Plants of the families acanthaceae-cucurbitaceae

Sixty-two plants are listed, which are used by traditional healers in the northeastern part of Tanzania. For each species are given: the botanical name with synonyms, vernacular name, collection number, locality, habitus, approximate distribution, and medical use. Results of a literature survey are also reported, including medical use, isolated constituents and pharmacological effects.

Inventory of plants used in traditional medicine in Tanzania. II. Plants of the families Dilleniaceae--Opiliaceae.

Forty five plants are listed, which are used by traditional healers in the northeastern part of Tanzania. For each species are given: the botanical name with synonyms, vernacular name, collection number, locality, habitus, approximate distribution and medical use. Results of a literature survey are also reported, including medical use, isolated constituents and pharmacological effects.

Inventory of plants used in traditional medicine in Tanzania. part iii. plants of the families papilionaceaevitaceae

Forty-six plants are listed, which are used by traditional healers in the northeastern part of Tanzania. For each species are given: the botanical name with synonyms; vernacular name; collection number; locality; habitus; approximate distribution and medical use. Results of a literature survey are also reported, including medical use, isolated constituents and pharmacological effects.

Inventory of plants used in traditional medicine in Somalia. II: Plants of the families combretaceae to labiatae

Fifty-nine plants are listed, which are used by traditional healers in the central and southern parts of Somalia. For each species are listed: the botanical name with synonyms, collection number, vernacular name, medicinal use, preparation of remedy and dosage. Results of a literature survey are also reported including medicinal use, substances isolated and pharmacological effects.

Inventory of plants used in traditional medicine in Somalia. I, Plants of the families acanthaceae-chenopodiaceae

Thirty-eight plants are listed, which are used by traditional healers in the central and southern parts of Somalia. For each species are listed: the botanical name with synonyms, collection number, vernacular name, medicinal use, preparation of remedy and dosage. Results of a literature survey are also reported including medicinal use, substances isolated and pharmacological effects.

Ligatoxin B, a new cytotoxic protein with a novel helix-turn-helix DNA-binding domain from the mistletoe Phoradendron liga.

A new basic protein, designated ligatoxin B, containing 46 amino acid residues has been isolated from the mistletoe Phoradendron liga (Gill.) Eichl. (Viscaceae). The proteins primary structure, determined unambiguously using a combination of automated Edman degradation, trypsin enzymic digestion, and tandem MS analysis, was 1-KSCCPSTTAR-NIYNTCRLTG-ASRSVCASLS-GCKIISGSTC-DSGWNH-46. Ligatoxin B exhibited in vitro cytotoxic activities on the human lymphoma cell line U-937-GTB and the primary multidrug-resistant renal adenocarcinoma cell line ACHN, with IC50 values of 1.8 microM and 3.2 microM respectively. Sequence alignment with other thionins identified a new member of the class 3 thionins, ligatoxin B, which is similar to the earlier described ligatoxin A. As predicted by the method of homology modelling, ligatoxin B shares a three-dimensional structure with the viscotoxins and purothionins and so may have the same mode of cytotoxic action. The novel similarities observed by structural comparison of the helix-turn-helix (HTH) motifs of the thionins, including ligatoxin B, and the HTH DNA-binding proteins, led us to propose the working hypothesis that thionins represent a new group of DNA-binding proteins. This working hypothesis could be useful in further dissecting the molecular mechanisms of thionin cytotoxicity and of thionin opposition to multidrug resistance, and useful in clarifying the physiological function of thionins in plants.

Structural studies on some saponins from Lecaniodiscus cupanioides

Abstract Four triterpenoid saponins isolated from the stem bark of Lecaniodiscus cupanioides and denoted S-2,S-3,S-4 and S-5, were identified as follows. S-2:3- O -[α- l -arabinopyranosyl-(1→3)-α- l -rhamnopyranosyl-(1→2)-α- l -arabinopyranosyl]-hederagenin; S-3:3- O -[α- d -xylopyranosyl-(1→3)-α- l -rhamnopyranosyl-(1→2)-α- l -arabino-pyranosyl ]-hederagenin; S-4:3- O - [α- l -arabinopyranosyl-(1→3)-α- l -rhamnopyranosyl-(1→ 2)-α- l -arabinopyranosyl]-hederagenin; S-5:3- O - [α- l -rhamnopyranosyl-(1→2)-α- l -arabinopyranosyl ]-hederagenin. Of these, S-2 and S-4 are new substances.

Small, novel proteins from the mistletoe Phoradendron tomentosum exhibit highly selective cytotoxicity to human breast cancer cells

Abstract. Four novel proteins (phoratoxins C–F) have been isolated from the North American mistletoe Phoradendron tomentosum. The amino acid sequences of these phoratoxins were determined unambiguously using a combination of Edman degradation and trypsin enzymatic digestion, and by electrospray ionization tandem mass spectrometry sequencing. Phoratoxins C, E and F consist of 46 amino acid residues; and phoratoxin D of 41. All proteins had six cysteines, similar to the earlier described phoratoxins A and B, which are thionins. The cytotoxicity of each protein was evaluated in a human cell line panel that represented several cytotoxic drug-resistance mechanisms. For the half-maximal inhibitory concentrations (IC50 values) of the different cell lines in the panel, correlation with those of standard drugs was low. The most potent cytotoxic phoratoxin C was further tested on primary cultures of human tumor cells from patients. The solid tumor samples from breast cancer cells were 18 times more sensitive to phoratoxin C than the tested hematological tumor samples.

Preliminary chemical characterization of pharmacologically active compounds in aqueous plant extracts

A test system is described which, based on the use of ion exchangers, gel filtration on Sephadex, and extraction with organic solvents, gives information about the stability, molecular size, charge, and polarity of pharmacologically active compounds in aqueous plant extracts. Knowledge of these properties permits development of a suitable isolation method for the compounds. The method is illustrated by the identification of quaternary ammonium salts as responsible for the contracting activity on the isolated guinea pig ileum of an aqueous extract of roots of Maeura subcordata.

Inventory of plants used in traditional medicine in Somalia. III. Plants of the families Lauraceae-Papilionaceae.

Thirty-five plants are listed, which are used by traditional healers in the central and southern parts of Somalia. For each species are listed: the botanical name with synonyms, collection number, vernacular name, medicinal use, preparation of remedy and dosage. Results of a literature survey are also reported including medicinal use, substances isolated and pharmacological effects.