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Volatile chemical constituents of four species of local bamboo (Schizostachyum blumei Nees., Schizostachyum brachycladum Nees., Schizostachyum lima (Blanco) Merrill and Schizostachyum pilosum S.Dransf.) were investigated. The oils were obtained from bamboo culm through steam distillation and profiled using Gas Chromatography-Mass Spectrometry (GCMS). A total of 59 volatile constituents were identified, and these contained oxygenated sesquiterpene, α-elemol (8.2~21.1 %), coumaran (6.7~32.3 %), guaiacol-4-vinyl (0.6~0.9 %), palmitic acid (1.5~25.6 %), pentacosane (0.1~0.2 %), phytol (1.0~12.6 %), phytol acetate (0.5~1.7 %) and trans-squalene (0.2~1.6 %) consistently in the specimens studied. Based on the observation, S. pilosum exhibited wider diameter of inhibition against Escherchia coli and Staphylococcus aureus compared to the other species of Schizostachyum essential oil.

Conservation of plant species plays a vital role in preventing the loss of valuable plant resources. The success of conservation depends on the correct identification and characterization of plant species. Bamboo is one of the most important plants with multiple uses that have contributed to the economy and socio-economy of many people in rural areas. It is under the subfamily of Bambusoideae that includes both woody and herbaceous bamboo. Conventionally, like other plants, bamboo has been classified dependently based on morphological characteristics. However, morphological identification leads to difficulties and misclassification of bamboo species due to their infrequent flowering behaviour and peculiar reproductive biology. Since then, molecular markers have been introduced to overcome the problems associated with bamboo taxonomy and phylogeny. This paper provides an overview of the diverse, predominantly molecular techniques used to assess and determine the genetic diversity of bamboo species.

The medicinal plant, Syzygium leucoxylon or commonly known as Obah found in North Borneo was considered as traditional medicine by local committee. Two new phenolics, leucoxenols A (1) and B (2) were isolated and identified as major secondary metabolites from the leaves of S. leucoxylon. Their chemical structures were elucidated based on spectroscopic data such as NMR and HRESIMS. Furthermore, these compounds were active against selected strains of fungi.

The antifungal activity of two Bornean medicinal wild gingers Plagiostachys megacarpa and Zingiber phillippsiae were examined against Lagenidium thermophilum. The most active extract was P. megacarpa at concentration of 320 µg/mL inhibiting both hyphal growth and zoospore production of L. thermophilum in 24 h. Toxicity tests were conducted using mud crab (Scylla tranquebarica) larva. Bath treatment of P. megacarpa at concentrations of 320 and 640 µg/mL for 24 h were highly effective against hyphae and zoospores of the strain and it is non-toxic to mud crab larva. Therefore, crude extracts P. megacarpa may be used as alternative treatment for marine Oomycete infection of mud crab.

Ethnomycological knowledge is a combination of biological resources, cultural and human patterns, in particular collective traditional uses and the importance of fungi in daily life. Despite the large number of ethnic groups in Sabah, the native ethnomycological knowledge of wild edible mushrooms and poisonous mushrooms are poorly documented. This study attempted to document wild edible mushrooms and their ethnomycological uses and practices in the tropical rainforest of Sabah, Borneo. Opportunistic samplings and ethnomycological surveys were made within the indigenous communities of Sabah. Collectively, 50 respondents from four different ethnic communities i.e. Dusun, Kadazan, Orang Sungai, and Bisaya were interviewed. A total of 25 wild mushroom species were documented as edible mushroom for food, and five species for medicinal uses. The highest number of wild edible mushroom collected and reported were of the Pleurotaceae family (five species), followed by Polyporaceae family (three species) and Auriculariaceae family (three species). The results also showed that Schizophyllum commune (Kulat Kodop), Volvariella volvacea (Kulat Sawit), Pleurotus spp., (Cendawan Tiram) Auricularia spp., (Kulat Korong) and Marasmiellus species were mostly consumed by the indigenous people of Sabah as part of their daily diet. Local names, culinary, and the edibility types were distinct among the different local communities. Elderly indigenous people possess vast knowledge on uses of wild mushrooms compared to the younger generation. Women play an important role in wild mushroom collection and its edibility, uses and practices. The findings from this study showed that ethnomycological knowledge of wild mushroom in Sabah is still lacking and more attention is needed. A study on the ethnomycological aspect in Borneo is a necessity in creating awareness among the public on edible and poisonous mushrooms, and its culinary and medicinal properties.

The essential oil composition of six species of wild Cinnamomum found in Borneo was investigated. The oils were obtained from bark by hydrodistillation and the volatile chemical profile was obtained via Gas Chromatography-Mass Spectrometry (GCMS). A total of 65 volatile constituents were identified, where the essential oils of the studied specimens contained high contents of oxygenated monoterpenes. Eucalyptol (1.2-31.1%), terpinen-4-ol (7.9-22.1%), eugenol (0.4-37.9%) and α-cadinol (0.4-1.8%) were detected consistently in the specimens studied. The oils of C. cuspidatum and C. crassinervium exhibited significant inhibition against Listeria monocytogenes, specifically the latter, which displayed a lower minimum bactericidal concentration (MBC) value against Staphylococcus aereus and L. monocytogenes. This result had highlighted the possible usage of the essential oil derived from wild cinnamom species against food borne pathogens.

A new flavonoid, dihydroglychalcone-A, was isolated from the leaves extract of Glycosmis chlorosperma in addition to two known sulphur-containing amides, dambullin and gerambullin. The structure of the new compound was assigned as 2'-hydroxy-4,6'-dimethoxy-3',4'-(2",2"-dimethylpyrano)dihydrochalcone. The extract of the leaves was also found to exhibit antimicrobial and cytotoxic activities.

The medicinal herbs, Smilax bracteata C. Presl. (Smilacaceae) or commonly known as Tongkung in North Borneo Island was used traditionally for treatment of ailments in various Dusun villages in Sabah, Malaysia. One aromatic compound seselin (1) and two steroids β-sitosterol (2) as well as stigmasti-4-ene-3-one (3) were isolated and identified as major secondary metabolites from this plant. Their chemical structures were elucidated using 1H, 13C and 2D NMR. These chemical compounds have shown to possess variety of biological activities such as anticancer, anti-fungal and anti-inflammatory. Therefore, the ailments of local native Dusun people in Sabah, Malaysia were treated due to the presence of these compounds in S. bracteata.

Dye Sensitized Solar Cell (DSSC) was first discovered in 1991 by O'regan and Gratzel. This new type of solar cell was reported to have lower production cost with efficiency as high as 12% which is comparable to conventional silicon solar cell. Initially, it uses ruthenium dye as light sensitizer for the operation. However, DSSC with ruthenium dyes are facing environment friendly issues due to the toxic chemicals and costly purification in processing ruthenium dye. Regardless of the poor performance in DSSC, natural dyes which are easy to prepare, cheap and environmental friendly still appear to be an alternative as dye sensitizer. In this study, dye sensitized solar cells (DSSCs) were fabricated using anthocyanin source dyes extracted from several local fruits. All the extracts absorb a wide range of the visible light and ultraviolet spectrum. Therefore, all of the natural dyes show light absorption properties which is important for a dye sensitizer. A DSSC is comprised of conductive substrate, nanoporous semiconductor TiO2 layer, dye sensitizer, electrolyte with redox couple and a counter electrode with catalyst. In this study, the effect of different light source and different counter electrode are been investigated. However, it is vital to know that further research need to do more on the locally Borneo sourced dyes to evaluate and enhance their performance in Dye Sensitized Solar Cell.

A new coumarin, 8,4''-dihydroxy-3'',4''-dihydrocapnolactone-2',3'-diol (1) and two known triterpenes, 5(6)-gluten-3-one (2) and 5(6)-gluten-3alpha-ol (3) were isolated from the leaves of Micromelum minutum (Rutaceae) collected from Sepilok, Sabah, Malaysia and their structures were characterized by spectroscopic methods.

The ethnobotanical studies of the Dusun people in Tikolod village, Tambunan district, Sabah, Malaysia were conducted from July 25th to 30th, 2011 and from March 9th to 10th, 2012. The result shows that there were 160 species in 62 families of plants used. Among them, there were 83 species (in 36 families) of edible plants, 75 species (in 44 families) were medicines, 12 species (in nine families) were used for constructions and handicraft and eight species (in six families) were used for musical instruments and animal traps. There were 24 species of plants that have two or more uses. Of the total, 87 species or 54% were native or collected from the natural forest nearby and 73 species or 45% of these plants were exotic (introduced plants). The most commonly used of plant families were Poaceae (Gramineae) with 14 species, followed by Moraceae and Zingiberaceae, with eight species each and Arecaceae (Palmae), Cucurbitaceae, Euphorbiaceae, Rutaceae and Solanaceae, with seven species each.

Two new aromatic compounds, phillipsins A (1) and B (2) were isolated from the Bornean wild ginger Zingiber phillippsii Mood & Theilade, and were characterized based on spectroscopic data (HRESI-MS, FTIR as well as 1D and 2D NMR). These metabolites also exhibited strong antifungal activity against selected fungi.