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Novel species of fungi described in this study include those from various countries as follows: Australia : Banksiophoma australiensis (incl. Banksiophoma gen. nov.) on Banksia coccinea , Davidiellomyces australiensis (incl. Davidiellomyces gen. nov.) on Cyperaceae , Didymocyrtis banksiae on Banksia sessilis var . cygnorum , Disculoides calophyllae on Corymbia calophylla , Harknessia banksiae on Banksia sessilis , Harknessia banksiae-repens on Banksia repens , Harknessia banksiigena on Banksia sessilis var . cygnorum , Harknessia communis on Podocarpus sp., Harknessia platyphyllae on Eucalyptus platyphylla , Myrtacremonium eucalypti (incl. Myrtacremonium gen. nov.) on Eucalyptus globulus , Myrtapenidiella balenae on Eucalyptus sp., Myrtapenidiella eucalyptigena on Eucalyptus sp., Myrtapenidiella pleurocarpae on Eucalyptus pleurocarpa , Paraconiothyrium hakeae on Hakea sp., Paraphaeosphaeria xanthorrhoeae on Xanthorrhoea sp., Parateratosphaeria stirlingiae on Stirlingia sp., Perthomyces podocarpi (incl. Perthomyces gen. nov.) on Podocarpus sp., Readeriella ellipsoidea on Eucalyptus sp., Rosellinia australiensis on Banksia grandis , Tiarosporella corymbiae on Corymbia calophylla , Verrucoconiothyrium eucalyptigenum on Eucalyptus sp., Zasmidium commune on Xanthorrhoea sp., and Zasmidium podocarpi on Podocarpus sp. Brazil : Cyathus aurantogriseocarpus on decaying wood, Perenniporia brasiliensis on decayed wood, Perenniporia paraguyanensis on decayed wood, and Pseudocercospora leandrae-fragilis on Leandra fragilis. Chile : Phialocephala cladophialophoroides on human toe nail. Costa Rica : Psathyrella striatoannulata from soil. Czech Republic : Myotisia cremea (incl. Myotisia gen. nov.) on bat droppings. Ecuador : Humidicutis dictiocephala from soil, Hygrocybe macrosiparia from soil, Hygrocybe sangayensis from soil, and Polycephalomyces onorei on stem of Etlingera sp. France : Westerdykella centenaria from soil. Hungary : Tuber magentipunctatum from soil. India : Ganoderma mizoramense on decaying wood, Hodophilus indicus from soil, Keratinophyton turgidum in soil, and Russula arunii on Pterigota alata. Italy : Rhodocybe matesina from soil. Malaysia : Apoharknessia eucalyptorum , Harknessia malayensis , Harknessia pellitae , and Peyronellaea eucalypti on Eucalyptus pellita , Lectera capsici on Capsicum annuum , and Wallrothiella gmelinae on Gmelina arborea. Morocco : Neocordana musigena on Musa sp. New Zealand : Candida rongomai-pounamu on agaric mushroom surface, Candida vespimorsuum on cup fungus surface, Cylindrocladiella vitis on Vitis vinifera , Foliocryphia eucalyptorum on Eucalyptus sp., Ramularia vacciniicola on Vaccinium sp., and Rhodotorula ngohengohe on bird feather surface. Poland : Tolypocladium fumosum on a caterpillar case of unidentified Lepidoptera. Russia : Pholiotina longistipitata among moss. Spain : Coprinopsis pseudomarcescibilis from soil, Eremiomyces innocentii from soil, Gyroporus pseudocyanescens in humus, Inocybe parvicystis in humus, and Penicillium parvofructum from soil. Unknown origin : Paraphoma rhaphiolepidis on Rhaphiolepsis indica. USA : Acidiella americana from wall of a cooling tower, Neodactylaria obpyriformis (incl. Neodactylaria gen. nov.) from human bronchoalveolar lavage, and Saksenaea loutrophoriformis from human eye. Vietnam : Phytophthora mekongensis from Citrus grandis , and Phytophthora prodigiosa from Citrus grandis. Morphological and culture characteristics along with DNA barcodes are provided.

Two distinct Phytophthora taxa were found to be associated with brown rot of pomelo (Citrus grandis), a new disease of this ancestral Citrus species, in the Vinh Long province, Mekong River Delta area, southern Vietnam. On the basis of morphological characters and using the ITS1-5.8S-ITS2 region of the rDNA and the cytochrome oxidase subunit 1 (COI) as barcode genes, one of the two taxa was provisionally named as Phytophthora sp. prodigiosa, being closely related to but distinct from P. insolita, a species in Phytophthora Clade 9, while the other one, was closely related to but distinct from the Clade 2 species P. meadii and was informally designated as Phytophthora sp. mekongensis. Isolates of P. sp. prodigiosa and P. sp. mekongensis were also obtained from necrotic fibrous roots of Volkamer lemon (C. volkameriana) rootstocks grafted with 'King' mandarin (Citrus nobilis) and from trees of pomelo, respectively, in other provinces of the Mekong River Delta, indicating a widespread occurrence of both Phytophthora species in this citrus-growing area. Koch's postulates were fulfilled via pathogenicity tests on fruits of various Citrus species, including pomelo, grapefruit (Citrus x paradisi), sweet orange (Citrus x sinensis) and bergamot (Citrus x bergamia) as well as on the rootstock of 2-year-old trees of pomelo and sweet orange on 'Carrizo' citrange (C. sinensis 'Washington Navel' x Poncirus trifoliata). This is the first report of a Phytophthora species from Clade 2 other than P. citricola and P. citrophthora as causal agent of fruit brown rot of Citrus worldwide and the first report of P. insolita complex in Vietnam. Results indicate that likely Vietnam is still an unexplored reservoir of Phytophthora diversity.

The methanolic extract from the leaves of the Vietnamese medicinal plant Maesa balansae showed potent in vitro and in vivo activity against the tropical protozoal parasite Leishmania infantum. Bioassay-guided purification of the extract led to the identification of six triterpenoid saponins, maesabalides I-VI (1-6), each having a strong and specific anti-leishmanial activity. Maesabalide III (3) and IV (4) were the most potent with IC(50) values against intracellular amastigotes of about 7 and 14 ng/mL. In comparison, the IC(50) value of sodium stibogluconate, the reference drug for treatment of leishmaniasis, is only 5.6 microg/mL. No cytotoxicity was present on a human fibroblast (MRC-5) cell line (CC(50) > 32 microg/mL). In vivo evaluation in the BALB/C mouse model demonstrated that >90% reduction of liver amastigote burdens was obtained 1 week after a single subcutaneous dose at 0.2-0.4 mg/kg was administered. Several chemical derivatives of maesabalides I-VI were prepared in order to study the structure-activity relationship.

Chemical investigation of the methanolic fraction of Lepisanthes rubiginosa bark has led to the isolation and characterisation of a new tetrasaccharide derivative of farnesol named rubiginoside along with known triterpenoid saponins.

The structure of soularubinone 3, a new antileukemic quassinoid isolated from the leaves of Soulamea tomentosa (Brongn, and Gris), has been established by spectral and chemical methods. It has been shown to be the C-15 beta-hydroxy-isovaleric ester of glaucarubolone. Soularubinone shows significant antineoplastic activity against mouse leukemia P-388 and inhibits cell transformation induced by Rous sarcoma virus. The known quassinoid chaparrinone I has also been isolated.