A study was conducted in a disturbed mangrove forest that had been gazetted as a national park in... more A study was conducted in a disturbed mangrove forest that had been gazetted as a national park in Sarawak, Malaysia. This study provides information regarding the status of disturbed mangroves and can be used as baseline data to support decision making in managing mangrove forests. The objectives of this study were to determine the tree species composition and structure of an exploited mangrove forest. This study was carried out in Kuching Wetland National Park (KWNP). Eight transects were established and in each transect sampling plots of 20 x 20m were established. All standing trees with a diameter at breast height (DBH) ≥ 5 cm within each plot were enumerated. Generally there are three major forest types in KNWP: mixed-mangrove forests, Sonneratia alba forest and heath or kerangas forest; a total of 98 species were recorded. Sonneratia alba forest dominates the sandy mud-flats. However, their occurrence is not extensive, being confined to areas along the rivers, coastlines and estuaries of Batang Salak opposite Pulau Salak. The forest occurs on the seaward fringe as a narrow strip about 20 – 30 meters wide. The vast majority of the mangrove area can be classified as mixed-mangrove forest composed of Rhizophora apiculata and Rhizophora mucronta interspersed with Xylocarpus granatum, Avicennia alba and Nypa fructicans. More than 60% of the mangroves are pole size with a DBH between 5 and 10 cm. Avicennia alba recorded the highest basal area with 4.5 m 2 /ha followed by Rhizophora apiculata (3.8 m 2 /ha) and Avicennia marina (1.3 m 2 /ha). Some areas in KNWP are made up of heath forests scattered throughout the interior of the park. The heath forest has a uniform single-layered canopy with trees reaching up to 22 m in height. There are no mangrove species in the heath forest and the common trees are Syzygium ochneocarpa, Whiteodendron moulto-nianum and Casuarina sumatrana. In general, the species composition in KNWP is rich and the regeneration status is good.
Interest in organotin(IV) compounds is increasing due to their interesting structural features an... more Interest in organotin(IV) compounds is increasing due to their interesting structural features and possession of biological activities. The objective of this study was to determine the efficacy of novel organotin(IV) complexes against Trametes versicolor and Gloeophyllum trabeum decay fungi. Soil block decay test was performed using
Acoustic properties such as specific dynamic Young's modulus (Ed/γ), internal friction (Q-1), and... more Acoustic properties such as specific dynamic Young's modulus (Ed/γ), internal friction (Q-1), and acoustic conversion efficiency (ACE) of wood are important properties frequently examined using free-free flexural vibration. This study determined the suitability for making musical instrument soundboards and frameboards from four tropical wood species; namely Syzygium, Dialium, Gymnostoma, and Sindora. The results show that (Ed/γ), (Q-1), and ACE were in the range of 20.0 to 28.9 GPa, 0.0031 to 0.0085, and 3.41×10 7 to 10.83×10 7 , respectively. Based on the results, Syzygium was preferred for making the frameboard of violins and guitars. The outer sapwood (outer part) of Syzygium was the most suitable for making frameboard by considering the lowest ACE and highest Q-1. Based on Ed/γ, the inner sapwood (middle part) in Dialium was the most suitable for making soundboard, but based on Q-1 and ACE, heartwood (inner part) was the most preferred for making soundboard. Gymnostoma was also preferred for making soundboard of violins and guitars (inner sapwood) because it yields the highest mean value of Q-1 and ACE. Considering ACE and Q-1 , the outer sapwood in Sindora was the best for making frameboard. When considering Ed/γ and Q-1 , the heartwood is the most suitable for making the frameboard of violins and guitars.
Two new tree variants, namely Acacia hybrid and second-generation Acacia mangium, have been intro... more Two new tree variants, namely Acacia hybrid and second-generation Acacia mangium, have been introduced in plantation forests in Sarawak, Malaysia, and their wood qualities were examined. The mean basic density of Acacia hybrid was comparable with Acacia mangium. However basic density and strength properties of second-generation A. mangium were significantly lower compared to Acacia hybrid. The mean fibre length and fibre wall thickness in the hybrid were found to be greater than that of second-generation A. mangium. Fibre diameter and fibre lumen diameter of Acacia hybrid were smaller compared to second-generation A. mangium. Runkel and slenderness ratios of Acacia hybrid and second-generation A. mangium fibres showed that they were suitable for pulp and paper production. Acacia hybrid was more resistant to Coptotermes curvignathus attack than second-generation A. mangium. A laboratory soil block test showed that Acacia hybrid and second-generation A. mangium were moderately durable timbers. In summary, marked differences in wood properties and qualities were observed between Acacia hybrid and second-generation A. mangium.
This study reported the isolation and in silico characterization of a full-length Xyloglucan endo... more This study reported the isolation and in silico characterization of a full-length Xyloglucan endotransglycosylase/Hydrolase (XTH) cDNA from Neolamarckia cadamba, an important tropical light hardwood plantation tree species. XTH is considered as a key agent to regulate cell wall expansion and is believed to be responsible for the incorporation of newly synthesised xyloglucan into the wall matrix. The full-length of NcXTH was firstly predicted using the XTH singletons from the NcdbEST through contig mapping approach. Further validation and confirmation were conducted by amplifying the full-length XTH cDNA using RT-PCR approach. Two full-length XTH cDNAs, namely NcXTH1 (JX134619) and NcXTH2 (JX134620) were discovered and the nucleotide sequences were 893 and 1,024 bp in length, respectively. The open reading frames for NcXTH1 and NcXTH2 were 858 and 915 bp, respectively. Results predicted that NcXTH1 and NcXTH2 proteins carry out XET activity but they are from different XTH family members. This full-length NcXTH cDNA can serve as good candidate genes in association genetics study which leads to Gene-Assisted Selection (GAS) in the N. cadamba tree breeding programme.
This study reported the isolation and in silico characterization of fulllength cellulose synthase... more This study reported the isolation and in silico characterization of fulllength cellulose synthase (CesA) cDNA from Neolamarckia cadamba, an important tropical plantation tree species. CesA is a member of processive glycosyltransferases that involved in cellulose biosynthesis of plants. CesA acts as a central catalyst in the generation of plant cell wall biomass or cellulose. It also plays an important role in regulating wood formation. The hypothetical full-length CesA cDNA (NcCesA1; JX134621) was assembled by contig mapping approach using the CesA cDNA sequences from NcdbEST and the amplified 5'-and 3'-RACE PCR sequences. The NcCesA1 cDNA has a length of 3,472 bp with 3,126 bp open reading frame encoding a 1,042 amino acid sequence. The predicted NcCesA1 protein contained N-terminal cysteine rich zinc binding domain, 7 putative Transmembrane Helices (TMH), 4 Umotifs that contain a signature D, D, D, QxxRW motif, an alternating Conserved Region (CR-P) and 2 Hypervariable Regions (HVR). These entire shared domain structures suggest the functional role of NcCesA1 is involved in glycosyltransferation of the secondary cell wall cellulose biosynthesis of N. cadamba. Sequence comparison also revealed the high similarity (90%) among NcCesA1 and PtrCesA2 of Populus tremuloides. This further implies the involvement of NcCesA1 that catalyzes the cellulose biosynthesis of secondary cell wall rather than primary cell wall. This full-length NcCesA1 cDNA can serve as good candidate gene in association genetics study which leads to Gene-Assisted Selection (GAS) in the N. cadamba tree breeding programme. Furthermore, the isolation of new CesA genes from tropical tree genomes is essential for enhancing knowledge of cellulose biosynthesis in trees that has many fundamental and commercial implications.
This study reported the isolation and in silico characterization of a full-length Xyloglucan endo... more This study reported the isolation and in silico characterization of a full-length Xyloglucan endotransglycosylase/Hydrolase (XTH) cDNA from Neolamarckia cadamba, an important tropical light hardwood plantation tree species. XTH is considered as a key agent to regulate cell wall expansion and is believed to be responsible for the incorporation of newly synthesised xyloglucan into the wall matrix. The full-length of NcXTH was firstly predicted using the XTH singletons from the NcdbEST through contig mapping approach. Further validation and confirmation were conducted by amplifying the full-length XTH cDNA using RT-PCR approach. Two full-length XTH cDNAs, namely NcXTH1 (JX134619) and NcXTH2 (JX134620) were discovered and the nucleotide sequences were 893 and 1,024 bp in length, respectively. The open reading frames for NcXTH1 and NcXTH2 were 858 and 915 bp, respectively. Results predicted that NcXTH1 and NcXTH2 proteins carry out XET activity but they are from different XTH family members. This full-length NcXTH cDNA can serve as good candidate genes in association genetics study which leads to Gene-Assisted Selection (GAS) in the N. cadamba tree breeding programme.
Chemical treatment is often used to improve the physical and mechanical properties of wood materi... more Chemical treatment is often used to improve the physical and mechanical properties of wood materials. In this study, wood polymer composites (WPC) were prepared from five types of tropical wood species by impregnating the woods with methyl methacrylate (MMA) combined with ...
In this study the tropical light hardwood species jelutong (Dyera costulata), terbulan (Endosperm... more In this study the tropical light hardwood species jelutong (Dyera costulata), terbulan (Endospermum diadenum), batai (Paraserianthes moluccana), rubberwood (Hevea brasiliensis), and pulai (Alstonia pneumatophora) were treated with benzene diazonium salt to improve their dynamic ...
African Journal of Traditional, Complementary and Alternative Medicines, 2006
... Jiben Roy 1 * , Diaa M. Shakleya 2 , Patrick S. Callery 2 and John G. Thomas 3. ... Similarly... more ... Jiben Roy 1 * , Diaa M. Shakleya 2 , Patrick S. Callery 2 and John G. Thomas 3. ... Similarly, the pharmacologically active principles in the volatile oil of black cumin (Morsi, 2001; Ghosheh et al., 1999; Hanafy and Hatem, 1991) were identified as: thymoquinone, dithymoquinone ...
Acta Crystallographica Section E Structure Reports Online, 2012
The synthesis and crystal structure of the title compound was determined in connection with recen... more The synthesis and crystal structure of the title compound was determined in connection with recent structural studies of organotin chlorido derivatives of thiosemicarbazones .
A study was conducted in a disturbed mangrove forest that had been gazetted as a national park in... more A study was conducted in a disturbed mangrove forest that had been gazetted as a national park in Sarawak, Malaysia. This study provides information regarding the status of disturbed mangroves and can be used as baseline data to support decision making in managing mangrove forests. The objectives of this study were to determine the tree species composition and structure of an exploited mangrove forest. This study was carried out in Kuching Wetland National Park (KWNP). Eight transects were established and in each transect sampling plots of 20 x 20m were established. All standing trees with a diameter at breast height (DBH) ≥ 5 cm within each plot were enumerated. Generally there are three major forest types in KNWP: mixed-mangrove forests, Sonneratia alba forest and heath or kerangas forest; a total of 98 species were recorded. Sonneratia alba forest dominates the sandy mud-flats. However, their occurrence is not extensive, being confined to areas along the rivers, coastlines and estuaries of Batang Salak opposite Pulau Salak. The forest occurs on the seaward fringe as a narrow strip about 20 – 30 meters wide. The vast majority of the mangrove area can be classified as mixed-mangrove forest composed of Rhizophora apiculata and Rhizophora mucronta interspersed with Xylocarpus granatum, Avicennia alba and Nypa fructicans. More than 60% of the mangroves are pole size with a DBH between 5 and 10 cm. Avicennia alba recorded the highest basal area with 4.5 m 2 /ha followed by Rhizophora apiculata (3.8 m 2 /ha) and Avicennia marina (1.3 m 2 /ha). Some areas in KNWP are made up of heath forests scattered throughout the interior of the park. The heath forest has a uniform single-layered canopy with trees reaching up to 22 m in height. There are no mangrove species in the heath forest and the common trees are Syzygium ochneocarpa, Whiteodendron moulto-nianum and Casuarina sumatrana. In general, the species composition in KNWP is rich and the regeneration status is good.
Interest in organotin(IV) compounds is increasing due to their interesting structural features an... more Interest in organotin(IV) compounds is increasing due to their interesting structural features and possession of biological activities. The objective of this study was to determine the efficacy of novel organotin(IV) complexes against Trametes versicolor and Gloeophyllum trabeum decay fungi. Soil block decay test was performed using
Acoustic properties such as specific dynamic Young's modulus (Ed/γ), internal friction (Q-1), and... more Acoustic properties such as specific dynamic Young's modulus (Ed/γ), internal friction (Q-1), and acoustic conversion efficiency (ACE) of wood are important properties frequently examined using free-free flexural vibration. This study determined the suitability for making musical instrument soundboards and frameboards from four tropical wood species; namely Syzygium, Dialium, Gymnostoma, and Sindora. The results show that (Ed/γ), (Q-1), and ACE were in the range of 20.0 to 28.9 GPa, 0.0031 to 0.0085, and 3.41×10 7 to 10.83×10 7 , respectively. Based on the results, Syzygium was preferred for making the frameboard of violins and guitars. The outer sapwood (outer part) of Syzygium was the most suitable for making frameboard by considering the lowest ACE and highest Q-1. Based on Ed/γ, the inner sapwood (middle part) in Dialium was the most suitable for making soundboard, but based on Q-1 and ACE, heartwood (inner part) was the most preferred for making soundboard. Gymnostoma was also preferred for making soundboard of violins and guitars (inner sapwood) because it yields the highest mean value of Q-1 and ACE. Considering ACE and Q-1 , the outer sapwood in Sindora was the best for making frameboard. When considering Ed/γ and Q-1 , the heartwood is the most suitable for making the frameboard of violins and guitars.
Two new tree variants, namely Acacia hybrid and second-generation Acacia mangium, have been intro... more Two new tree variants, namely Acacia hybrid and second-generation Acacia mangium, have been introduced in plantation forests in Sarawak, Malaysia, and their wood qualities were examined. The mean basic density of Acacia hybrid was comparable with Acacia mangium. However basic density and strength properties of second-generation A. mangium were significantly lower compared to Acacia hybrid. The mean fibre length and fibre wall thickness in the hybrid were found to be greater than that of second-generation A. mangium. Fibre diameter and fibre lumen diameter of Acacia hybrid were smaller compared to second-generation A. mangium. Runkel and slenderness ratios of Acacia hybrid and second-generation A. mangium fibres showed that they were suitable for pulp and paper production. Acacia hybrid was more resistant to Coptotermes curvignathus attack than second-generation A. mangium. A laboratory soil block test showed that Acacia hybrid and second-generation A. mangium were moderately durable timbers. In summary, marked differences in wood properties and qualities were observed between Acacia hybrid and second-generation A. mangium.
This study reported the isolation and in silico characterization of a full-length Xyloglucan endo... more This study reported the isolation and in silico characterization of a full-length Xyloglucan endotransglycosylase/Hydrolase (XTH) cDNA from Neolamarckia cadamba, an important tropical light hardwood plantation tree species. XTH is considered as a key agent to regulate cell wall expansion and is believed to be responsible for the incorporation of newly synthesised xyloglucan into the wall matrix. The full-length of NcXTH was firstly predicted using the XTH singletons from the NcdbEST through contig mapping approach. Further validation and confirmation were conducted by amplifying the full-length XTH cDNA using RT-PCR approach. Two full-length XTH cDNAs, namely NcXTH1 (JX134619) and NcXTH2 (JX134620) were discovered and the nucleotide sequences were 893 and 1,024 bp in length, respectively. The open reading frames for NcXTH1 and NcXTH2 were 858 and 915 bp, respectively. Results predicted that NcXTH1 and NcXTH2 proteins carry out XET activity but they are from different XTH family members. This full-length NcXTH cDNA can serve as good candidate genes in association genetics study which leads to Gene-Assisted Selection (GAS) in the N. cadamba tree breeding programme.
This study reported the isolation and in silico characterization of fulllength cellulose synthase... more This study reported the isolation and in silico characterization of fulllength cellulose synthase (CesA) cDNA from Neolamarckia cadamba, an important tropical plantation tree species. CesA is a member of processive glycosyltransferases that involved in cellulose biosynthesis of plants. CesA acts as a central catalyst in the generation of plant cell wall biomass or cellulose. It also plays an important role in regulating wood formation. The hypothetical full-length CesA cDNA (NcCesA1; JX134621) was assembled by contig mapping approach using the CesA cDNA sequences from NcdbEST and the amplified 5'-and 3'-RACE PCR sequences. The NcCesA1 cDNA has a length of 3,472 bp with 3,126 bp open reading frame encoding a 1,042 amino acid sequence. The predicted NcCesA1 protein contained N-terminal cysteine rich zinc binding domain, 7 putative Transmembrane Helices (TMH), 4 Umotifs that contain a signature D, D, D, QxxRW motif, an alternating Conserved Region (CR-P) and 2 Hypervariable Regions (HVR). These entire shared domain structures suggest the functional role of NcCesA1 is involved in glycosyltransferation of the secondary cell wall cellulose biosynthesis of N. cadamba. Sequence comparison also revealed the high similarity (90%) among NcCesA1 and PtrCesA2 of Populus tremuloides. This further implies the involvement of NcCesA1 that catalyzes the cellulose biosynthesis of secondary cell wall rather than primary cell wall. This full-length NcCesA1 cDNA can serve as good candidate gene in association genetics study which leads to Gene-Assisted Selection (GAS) in the N. cadamba tree breeding programme. Furthermore, the isolation of new CesA genes from tropical tree genomes is essential for enhancing knowledge of cellulose biosynthesis in trees that has many fundamental and commercial implications.
This study reported the isolation and in silico characterization of a full-length Xyloglucan endo... more This study reported the isolation and in silico characterization of a full-length Xyloglucan endotransglycosylase/Hydrolase (XTH) cDNA from Neolamarckia cadamba, an important tropical light hardwood plantation tree species. XTH is considered as a key agent to regulate cell wall expansion and is believed to be responsible for the incorporation of newly synthesised xyloglucan into the wall matrix. The full-length of NcXTH was firstly predicted using the XTH singletons from the NcdbEST through contig mapping approach. Further validation and confirmation were conducted by amplifying the full-length XTH cDNA using RT-PCR approach. Two full-length XTH cDNAs, namely NcXTH1 (JX134619) and NcXTH2 (JX134620) were discovered and the nucleotide sequences were 893 and 1,024 bp in length, respectively. The open reading frames for NcXTH1 and NcXTH2 were 858 and 915 bp, respectively. Results predicted that NcXTH1 and NcXTH2 proteins carry out XET activity but they are from different XTH family members. This full-length NcXTH cDNA can serve as good candidate genes in association genetics study which leads to Gene-Assisted Selection (GAS) in the N. cadamba tree breeding programme.
Chemical treatment is often used to improve the physical and mechanical properties of wood materi... more Chemical treatment is often used to improve the physical and mechanical properties of wood materials. In this study, wood polymer composites (WPC) were prepared from five types of tropical wood species by impregnating the woods with methyl methacrylate (MMA) combined with ...
In this study the tropical light hardwood species jelutong (Dyera costulata), terbulan (Endosperm... more In this study the tropical light hardwood species jelutong (Dyera costulata), terbulan (Endospermum diadenum), batai (Paraserianthes moluccana), rubberwood (Hevea brasiliensis), and pulai (Alstonia pneumatophora) were treated with benzene diazonium salt to improve their dynamic ...
African Journal of Traditional, Complementary and Alternative Medicines, 2006
... Jiben Roy 1 * , Diaa M. Shakleya 2 , Patrick S. Callery 2 and John G. Thomas 3. ... Similarly... more ... Jiben Roy 1 * , Diaa M. Shakleya 2 , Patrick S. Callery 2 and John G. Thomas 3. ... Similarly, the pharmacologically active principles in the volatile oil of black cumin (Morsi, 2001; Ghosheh et al., 1999; Hanafy and Hatem, 1991) were identified as: thymoquinone, dithymoquinone ...
Acta Crystallographica Section E Structure Reports Online, 2012
The synthesis and crystal structure of the title compound was determined in connection with recen... more The synthesis and crystal structure of the title compound was determined in connection with recent structural studies of organotin chlorido derivatives of thiosemicarbazones .
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