TAXONOMIC IDENTITY OF ARISAEMA CONDAOENSE (ARACEAE) BASED ON NEW MORPHOLOGICAL AND MOLECULAR DATA

Arisaema condaoense V.D. Nguyen was described as a new species from Con Dao National Park, Ba Ria–Vung Tau Province, Vietnam in 2000. However, this species has been suspected of being a form of Arisaema roxburghii Kunth, a species widespread in the whole Indochina and Malay Peninsula. This was due to the original description based on dried specimens with male inflorescences only. Morphological characteristics of female inflorescences, which are of taxonomical importance to identify the species, have not been known. In June 2015, we re-sampled the plant in Con Dao National Park with both male and female inflorescences for detailed examination of morphological characteristics. Besides, the matK gene of the chloroplast genome of this species was sequenced to analyse its phylogenetic relationship with other Arisaema species. The gathered morphological and molecular data indicate that A. condaoense is certainly a distinct species, not a synonym of A. roxburghii. The noted morphological characteristics also provide key differences to distinguish A. condaoense from two other morphologically close species of sect. Fimbriata (i.e A. maxwellii from Thailand and A. pierreanum from Vietnam which also share yellow spathes and several other characteristics in common), which are supported by the molecular data. Thus, the species is endemic to Con Dao National Park in Ba Ria–Vung Tau Province, Vietnam. Furthermore, this study allows us revising the description of A. condaoense with, for the first time, supplemental key taxonomic characteristics and illustrating colourful photographs taken from the fresh materials. A key to all eight known Vietnamese species of sect. Fimbriata is also given

CAMELLIA SPHAMII (THEACEAE, SECT. PIQUETIA), A NEW TAXON OF YELLOW FLOWER FROM LANGBIANG BIOSPHERE RESERVE, VIETNAM

Camellia sphamii is described and illustrated as a new species of section Piquetia from Hamasin village, D’ran town, Don Duong district, Lam Dong province, Vietnam. C. sphamii is similar to C. proensis (Quach, Luong et al., 2021) but differs from it in several morphological features: mature leaves cordate at base, young leaves purple; pericarp 7–8 mm thick with dense hair on the outer surface, flower buds ovate, ferruginous; sepals 5, hemisphere, concave, finely hairy on the outer surface, sparsely hairy on the inside, petals 7, finely hairy on the outer surface, with translucent margin, concave; style 5, ½ basally united; capsule 5 locular. Information on its phenology, distribution, ecology, and conservation status is also provided

Factors influencing the occurrence of labour accidents in Vietnamese residential construction projects

There was a sharp increase in the annual injury rate and the annual death rate per 100,000 employees in the Vietnam construction industry (VCI) from 2000 to 2006. This study aimed to identify and analyze factors affecting the occurrence of labour accidents (OLA) in residential construction projects. A survey questionnaire was used to collect data from construction practitioners. The results show that labour accidents in the VCI resulted from factors related to unqualified construction resources, unsafe human behaviour and poor management. The results can be used to gain insight into the OLA in order to deal with high labour accident rate and to develop safety programs in Vietnam as well as in other developing countries

EXTRACTION AND PROPERTY STUDIES OF COENZYME Q10 FROM RECOMBINANT AGROBACTERIUM TUMEFACIENS

In this report, some results of extraction and characterization of CoQ10 from recombinant A. tumefaciens are presented. Four different cell breaking methods (sonication, acidic treatment, ethanol treatment, and enzymatic lysis) in combination with the extracting steps were carried out to extract CoQ10 and the results showed that ethanol treatment was the most efficient method. Appropriate conditions for CoQ10 extraction were 25 oC, 24 hours incubation and ethanol solvent/biomass ratio of 10:1 (ml/g). Characterization of extracted CoQ10 showed that CoQ10 was sensitive to light, but stable in the temperature ranges of 4 – 60 oC and the pH range of 6.0 – 9.0. Obtained results in present study should be applied in the large scale for CoQ10 extraction, providing the CoQ10 product for testing production of functional foods

Billolivia cadamensis (Gesneriaceae), a new species from Central Vietnam

Billolivia cadamensis (Gesneriaceae) is described as a new species from the central province of Quang Ngai, Vietnam. The new taxon is close to B. tichii but differs in shorter stem, abaxially glabrous bracts, calyx divided into 5 lobes to base, outside pubescent apical half of corolla tube, oblong or deltoid corolla lobes, dense hairs on apical 3/4 of the ovary and white corolla lobes. A key to all known species of Billolivia of Vietnam is given.  Received 3 November 2016, accepted 27 December 2016, published online 28 December 201

Diet of the Annamese langur (Trachypithecus margarita) (Elliot, 1909) at Takou Nature Reserve, Binh Thuan Province, Vietnam

The Annamese langur (Trachypithecus margarita) was described in 1909 but its ecology, including its feeding behaviour, is still largely unknown. Based on current knowledge of feeding ecology of many Asian langurs, T. margarita is expected to be a generalist herbivore, with seasonal variation in diet. Feeding behaviour of one habituated group of Annamese langurs at Takou Mountain was studied from October 2009 to September 2011. The dietary pattern of these langurs was found to be similar to other Trachypithecus species, which is characterised by a high amount of leaf consumption (54.4% immature leaves, 7.1% mature leaves) and complemented by fruits (29.9%). The Annamese langurs ate plant parts from 31 species belonging to 20 families on Takou Mountain where 689 plant species were known for the mountain. Moraceae is the most important family in the langur's diet with at least 10 species consumed and accounting for 41.1% of feeding time. Based on the current and previous feeding studies of Trachypithecus species, it could be concluded that the genus is a generalist folivore and the dietary pattern is similar among species.</p

A comprehensive study in efficacy of Vietnamese herbal extracts on whiteleg shrimp (<em>Penaeus vannamei</em>) against <em>Vibrio parahaemolyticus</em> causing acute hepatopancreatic necrosis disease (AHPND)

Traditional Vietnamese herbal species were examined for their antimicrobial activity and disease resistance in whiteleg shrimp. In-vitro screening, the extracts of ten herbs were conducted to test the inhibition ability against Vibrio parahaemolyticus, causing acute hepatopancreatic necrosis disease. The results showed that five out of ten herbal species, including Pithecellobium dulce, Melaleuca leucadendron, Eucalyptus globulus, Mimosa pirga, and Hibiscus sabdariffa displayed potent antibacterial activity. Besides, three types of extracts of H. sabdariffa, E. globulus, and M. pirga were coated to the pellet feed at a concentration of 1%. After 30 days of feeding, the whiteleg shrimp (Penaeus vannamei) were challenged by V. parahaemolyticus through immersion. The growth performance (such as growth rate in length and weight, survival rate), hematological parameters of total hemocytes (THC), hyaline hemocytes (HC), and granulocytes (GC), and hepatopancreas recovery under the treatments with herbal extracts of the whiteleg shrimp were significantly enhanced as compared with the control (without herbal extract). The mortality and the bacterial density in the hepatopancreas of shrimp decreased. Specifically, the mortality of shrimp in the treatment supplemented with the methanol extract of H. sabdariffa was the lowest, followed by M. pirga and E. globulus. The experimental results also indicated that H. sabdariffa, E. globulus, and M. pirga could improve immune parameters and disease resistance; therefore, they should be employed in sustainable shrimp, practical farming

Conamomum odorum , a new species of Zingiberaceae from central Vietnam

Conamomum odorum is described as a new species from Khanh Hoa Province, Central Vietnam. It is characterized by sweet smell, striate and narrowly elliptic leaf leaves with short petiole and ligule, ovoid congested inflorescence, pubescent calyx, cream corolla lobes, yellow, obovate and reflexed labellum with median red bands at base and hairy ovary. The new species is illustrated with detailed photographs of key characters and morphologically compared to its closest congeners C. piereanum and C. rubidum. A distribution map of the genus in Vietnam is provided.

A new species of Typhonium (Araceae) from Vietnam

Typhonium obtusum is described as a new species endemic to Vietnam. It is unique in the genus in having an oblong-elliptic spathe limb with an obtuse apex and yellowish-greenish filiform staminodes with a down-curved acumen. The ecology, distribution and assessment of the conservation status of the new taxon, as well as a key to all known Typhonium species in Vietnam, are provided