The genus Alternaria Nees ex Fr. (Dematiaceae) contains a number of species pathogenic to econom­ ically important crop plants [1]. Perhaps not unre­ lated to this is the fact that the Alternaria are a rich source of biologically active secondary metabolites [2], several of which are phytotoxic [3]. In fact, with the possible exception of the genus H elm inthosporium Link ex Fries, more phytoto...

Two new species in the Matelea stenopetala complex (Apocynaceae, Asclepiadoideae) are described from the Guiana Shield and Amazonian Brazil: Matelea brevistipitata Krings & Morillo, sp. nov. and Matelea trichopedicellataKrings & Morillo, sp. nov. The new species belong to a small group of adaxially-pubescent-flowered taxa within the complex, including Matelea hildegardiana and Matelea pakaraime...

PURPOSE The objective of the present study was to evaluate the protective effect of methanol extract of Prosopis cineraria (MPC) against N-nitrosodiethylamine (DEN, 200mg/kg) induced Phenobarbital promoted experimental liver tumors in male Wistar rats. METHODS The rats were divided into four groups, each group consisting of six animals. Group 1 served as control animals. Liver tumor was induc...

The present work aimed at studying the effect of Ambrosia maritima (Damsissa) on the viability of Lymnaea snails. Lymnaea snails used in these trials were acclimatized to laboratory conditions before use in the toxicity test. The snails were exposed to various concentrations (100-3000 mg/l) of dry powdered Damsissa, Ambrosia maritima was lethal to Lymnaea snails at concentration of 3000 mg/L af...

BACKGROUND Thermotoga maritima and T. neapolitana are hyperthermophile bacteria chosen by many research teams to produce bio-hydrogen because of their potential to ferment a wide variety of sugars with the highest theoretical H2/glucose yields. However, to develop economically sustainable bio-processes, the culture medium formulation remained to be optimized. The main aim of this study was to q...

Alkaloid profiles of five Senecio species (Asteraceae), including S. ambiguus subsp. ambiguus, S. ambiguus subsp. nebrodensis, S. gibbosus subsp. bicolor, S. gibbosus subsp. gibbosus, and S. gibbosus subsp. cineraria, were studied. Eleven pyrrolizidine alkaloids were identified and their content was evaluated by GLC-MS and GLC analysis. Otosenine and florosenine were found to be the major alkal...

Thermotoga maritima, a fermentative, anaerobic, hyperthermophilic bacterium, was found to attach to bioreactor glass walls, nylon mesh, and polycarbonate filters during chemostat cultivation on maltose-based media at 80 degrees C. A whole-genome cDNA microarray was used to examine differential expression patterns between biofilm and planktonic populations. Mixed-model statistical analysis revea...

As a step towards studying representative members of the two-component family of signal transduction proteins, we have cloned genes encoding a histidine protein kinase and a response regulator from the hyperthermophilic bacterium Thermotoga maritima. The genes have been designated HpkA and drrA, respectively. The deduced HpkA sequence contains all five characteristic histidine protein kinase mo...

(Seed characteristics and dispersal of dimorphic fruits segments of Cakile maritima Scopoli (Brassicaceae) population of southern Brazilian coastal dunes). Cakile maritima occurs sporadically along the southern Brazilian coast, where it is restricted to more protected sites at the base of foredunes. Somatic dimorphism in C. maritima is manifested as morphologically distinct upper and lower frui...

Acetohydroxyacid synthase (AHAS) is the key enzyme in branched chain amino acid biosynthesis pathway. The enzyme activity and properties of a highly thermostable AHAS from the hyperthermophilic bacterium Thermotoga maritima is being reported. The catalytic and regulatory subunits of AHAS from T. maritima were over-expressed in Escherichia coli. The recombinant subunits were purified using a sim...