Expensive Wood Research Articles

The Opportunity Cost Analysis of using Jack Fruit Timber as a Construction Material in Sri Lanka


 
 
 
 The miracle tree in the world is thought to be the jackfruit tree. Its fruit-bearing capacity was well- documented by history academics. However, jackfruit wood is also regarded as one of Sri Lanka's more expensive wood types. Instead of considering the quality of the actual lumber material, this is only dependent on its legendary value. It was not considered how much money the timber was worth. They are carelessly used as one of the finest luxury lumber materials, disregarding the fact that they were originally planted as fruit trees. In an effort to compare the true worth of jackfruit wood to the current palette of premium timber materials, this study was initiated. Thus, it will assist legislators in passing a new law that forbids Sri Lanka from using jackfruit trees as a source of lumber. First, a life cycle model was used to determine the yield value and market value of jackfruit timber. The perceived value of the timber and the yield were then contrasted with the timber's real market worth. The study discovered that, before the age of 50 years, the jack fruit tree's yield value was significantly higher than its timber value. Only Rs. 100,000.00 is the typical timber value anticipated from a jackfruit tree. Only eight years of average yield value are required to restore the value of the timber. In order to preserve the jack fruit tree as one of the top fruit-bearing trees in the world, a new policy should be developed to change the jack fruit tree cutting age to a minimum of 50 years.
 Keywords: Jack fruit tree, Yield value, Selling price, Timber value
 
 
 

Gas chromatography mass spectrometry couple with quadrupole time-of-flight (GC-QTOF MS) as a powerful tool for profiling of oxygenated sesquiterpenes in agarwood oil

Agarwood (Aquilaria malaccensis) is very well known as the most expensive wood in the world due to its wide applications in perfumery, cosmetic traditional medicine, and religious ceremonies. The study aimed to give an in-depth characterisation focusing on marker compounds in A. malaccensis from different places in Malaysia. The establishment of an oxygenated sesquiterpenes chemical profile of the fungus-infected agarwood oil was achieved by gas chromatography mass spectrometry (GC–MS) coupled with quadrupole time (QTOF) technique. Aroma compounds were identified as sesquiterpenes and oxygenated sesquiterpenes where agarospirol was found in samples of all locations (3.12%, 3.54%, 3.36% and 2.26% from Melaka, Pahang, Kelantan A and Kelantan B respectively) and also N-hexadecanoic acid as one of the major compounds. Both compounds were further isolated by Prep-GC and confirmed by NMR. This study provides a reference for agarwood oil analysis from different origins in Malaysia.

Expression Pattern of in vitro Organogenesisassociated Genes as Transcriptional Marker in Sandalwood (Santalum album L.) Micropropagation

The world's most expensive wood, sandalwood (Santalum album L.), requires a stringent mass-propagation technique to prevent future scarcity. Plant tissue culture is an efficient method that regenerates the whole plant from a single cell on a hormone-based growth medium. To efficiently regulate the formation of plants, it is important to understand the developmental organogenesis pathways (i.e., direct and indirect) through gene expression studies. Therefore, an effective protocol for the direct and indirect organogenesis of sandalwood was developed, followed by the characterization of gene expression patterns in investigation. Five in vitro organogenesis genes namely, Alternative oxidase (ao), Late embryogenesis abundant (lea), Cytochrome p450 (cyt-p450), ABC transporter (abct), and Serine-threonine phosphatase (stp), were screened from three stages of sandalwood development; (1) inoculated leaf, (2) proliferated leaf shoot/callus formation and (3) shoot formation. The best treatments for plant regeneration in Woody Plant Media (WPM) were SI24 (2.5 mg/l 2,4-D) for indirect organogenesis and SD14 (2.0 mg/l BAP and 0.4 mg/l-1 NAA) for direct organogenesis. During the initial stages of organogenesis, ao, cyt-p450 and abct showed no/little change in expression in the direct pathway however up-regulation of ao and abct and downregulation of cyt-p450 were observed in the indirect pathway. Expression of lea was increased up to 70-fold during direct and dropped to half during indirect organogenesis. The optimization of the sandalwood organogenesis regeneration medium and the identification of distinct gene expression patterns will serve as transcriptional markers for the early prediction of the organogenesis stage, assisting in the sandalwood conservation. Plant Tissue Cult. & Biotech. 32(2): 103-113, 2022 (December)

Study on Profitability of Combining Wood and CFRP into Composite Based on Mechanical Performance of Bent Beams

The paper attempts to estimate the profitability of combining wood and CFRP into a composite (BSH-CFRP), intended to be used in load-bearing beams, including mechanical performance and prices of constituent materials. Prices of glue laminated timber (BSH) and CFRP tapes over the years were provided by ABIES Poland Ltd. and S&P Poland Ltd. companies. Referring to the uncertainty of wood prices on the market, two levels of BSH prices were adopted. A prediction of the beams’ mechanical behaviour was made based on the analytical model prepared by the author. The calculated members varied in width, height and length and included twelve types of CFRP tapes (different thickness, width and modulus of elasticity) glued between wooden lamellas. The total cost of each BSH-CFRP beam was compared to the total cost of the corresponding BSH beam in GL24h class, which led to calculating a cost multiplier. Consecutively, the multiplier was referred to the standard class improvement of BSH according to the bending stiffness and load-bearing capacity. A cloud of points got from many analyses resulted in obtaining exponential approximating functions. The averaged results led to general conclusions that at the assumed price level, improving the BSH standard class by using CFRP tapes was associated with a 1.86 BSH cost in the case of expensive wood or 2.81 in the case of cheap wood. Improving class by two was connected with the 3.55 BSH cost for expensive wood, and 6.79 for cheap wood. At present, the profits from composing wood with CFRP appear to be not very high in terms of their price. However, they can radically increase, especially when wood cutting limits are imposed on manufacturing companies, which significantly reduce the available timber for construction use.

Genome-wide mining of simple sequence repeats and development of polymorphic SSR markers in Aquilaria malaccensis

Aquilaria malaccensis is one of the economically important tree species distributed in North-east India which produces oleoresinous heartwood known as Agarwood - the most expensive wood in the world. There are limited genomic resources in this species. Therefore, the publicly available whole-genome sequence of Aquilaria agallocha, which is a synonym of A. malaccensis, was utilized for genome-wide mining of Simple Sequence Repeats (SSR) and to develop polymorphic SSR markers. In total 2,53,155 SSRs were identified from the draft genome. Primers were designed for di-nucleotide and tri-nucleotide repeats and screening of 90 such primers have resulted in the identification of 10 polymorphic markers. The present report is the first one for exhaustive identification of SSRs from the draft genome of the species. The SSR markers identified in the present study may be efficient in genomic analyses and useful in the genetic assessment and conservation of A. malaccensis.

Expression Pattern of in Vitro Organogenesis-Associated Genes as Transcriptional Marker in Indian Sandalwood (Santalum Album L.)

Indian sandalwood (Santalum album L.) is an expensive wood that requires reproducible method for mass propagation to ensure sustainable use. Organogenesis employs different combinations of the medium;. its suitability is decided based on the explant’s morphological changes. Early prediction of organogenesis in the explant helps reduce the combinations thereby saving time and resources. We initially developed an efficient protocol for the direct and indirect organogenesis (up to shooting development phase) of sandalwood in the present investigation. Woody Plant Media (WPM) supplemented with various concentrations of 6-Bezylaminopurine (BAP) and 1-Naphthaleneacetic acid (NAA) were tested for direct organogenesis, while different treatments consisting of various levels of 2,4-dichlorophenoxyacetic acid (2,4-D), NAA, BAP, Adenine sulphate (ADS), glycine and potassium nitrate were tested for indirect organogenesis.Three stages of leaf development were selected viz., the leaf just after inoculation in WPM media, initial stage of callus formation from leaf and shoot formation for expression pattern analysis. The targeted genes were Alternative oxidase (ao), Late embryogenesis abundant (lea), Cytochrome P450 (cyt-p450), ABC transporter (abct), and Serine-threonine phosphatase (stp) which are associated with in vitro organogenesis. The expression patterns were evaluated to identify a transcription marker. During the initial stages of organogenesis, ao, cyt-p450 and abct showed no/little change in expression in thedirect pathway but up-regulation of ao and abct and downregulation of cyt-p450 were observed in the indirect pathway. Expression of lea was increased up to 70-fold during direct and dropped to half during indirect organogenesis.

Recovering Evaluation of Narrow-Kerf Teeth of Mini Sash Gang Saws

Sash gang saws with narrow-kerf saw blades are used in the production of glued laminate flooring elements in plants where dry technology is applied. This means that boards or friezes are sawn into top layer lamellae in dry conditions (moisture content of about 10–12%) from expensive wood species, often exotic. The object of this research was stellite-tipped teeth of narrow kerf saw blades sharpened under industrial conditions. A NIKON ECLIPSE Ti-S microscope equipped with a NIKON DS-Fi2 recording camera was used to take pictures of teeth, which were analysed in a graphical software to measure the radii of the main cutting edges. The high-quality images obtained were used to determine the values of the rounding radii of the cutting edges. It was noted that the quality of edges regenerated in industrial conditions, some of which had chipping, was lower than that of brand new saw blades.

Wettability and Treatability of Sengon (Paraserianthes falcataria (L.) I.C. Nielsen) wood from NTB

The supply of wood from natural forests is decreasing as a result of the imbalance between harvesting and planting. The lack of wood supply from natural forests has resulted in relatively expensive wood prices. This can be anticipated by using fast-growing wood species. One type of fast-growing wood which is very abundantly available in NTB is sengon wood (Paraserianthes falcataria (L.) I.C. Nielsen). However, sengon wood has low durability so it is easily attacked by wood-destroying organisms. This condition can be overcome by making efforts to prevent wood damage in the form of preservation. This study aims to determine the wettability and treatability properties of sengon wood. The results of this study are expected to be basic information to improve the quality of sengon wood. The wettability test was carried out by measuring the contact angle between the liquid and the sample surface using the sessile drop method and the wood durability testing was carried out by measuring the retention and penetration of preservatives. The treatability test was carried out by measuring the absorption, retention, and penetration of preservatives. The results showed that the wettability of sengon is high with an equilibrium contact angle (θe) of 16.88 in the radial section and 12.51 in the tangential section. This shows that sengon wood has a good adhesion system for preservation. Treatability of sengon wood showed that the average retention and penetration are 10,21 kg/m3 and 7,33 mm. Based on the results of these measurements, sengon wood has met SNI 03-5010.1-1999 (wood preservation for housing and buildings).

Morpho-genetic divergence and population structure in Indian Santalum album L.

Morpho-genetic divergence study on Santalum album suggested maximum divergence is present in the south Indian populations with propagation throughout the rest of India from the south. Santalum album L. is highly valuable among Indian forest tree species and considered as the second most expensive wood in the world. Sandalwood oil present in the heartwood of the tree is used in perfumery, aromatherapy, and pharmaceuticals. Due to its high value heartwood oil, sandalwood trees are being harvested unsustainably from natural populations, resulting in a substantial decline in populations which has led to its inclusion in the vulnerable category of the IUCN Red List. Management of this important tree species in its natural area needs critical attention, because it may face a loss of genetic diversity due to exhaustive exploitation. The present study is the first of its kind that aimed to evaluate morphological and genetic variation as well as population structure of S. album using different markers assay from geographically widespread populations of India. A total of 37 primers (15 RAPD and 22 ISSR) were used to characterize total genetic diversity in S. album. RAPD markers detected 69.94% polymorphism, while ISSR markers were able to detect 72.92% polymorphism in the species. Based on the polymorphic information content, marker index, and resolving power, RAPD markers were found to be slightly superior to the ISSR markers. The UPGMA dendrogram based on cumulative RAPD and ISSR data grouped the accessions in two main clusters, which was also supported by the principal component analysis. AMOVA analysis suggested that maximum genetic variation was present within populations (RAPD 86.59%; ISSR 85.40%), with less variation among populations (RAPD 13.41%; ISSR 14.60%). Furthermore, maximal morpho-variations were found to be present in the south Indian populations. Morphological and genetic data did not show correlation, but both the markers showed a goodness-of-fit correlation (r = 0.44: p < 0.0001). The study revealed the presence of low genetic variability in S. album, which mandates immediate attention towards its sustainable utilization, propagation, and long term conservation.

On the History of Artistic Finishes of Russian Furniture of the 19th Century

The article is devoted to the technologies of the finishing works of furniture in the second half of the 19th century. During this period, the imitation of expensive wood, using cheaper woods, became a common practice. The most popular method was the imitation of walnut wood. This finishing was used both for palace furniture and pieces of furniture made by craftsmen. Numerous handbooks published instructions that were used for the imitation of expensive materials. The analysis of the instructions published, revealed their frequent repeatability. The research, which took place during restoration work, made it possible to describe some of them. Particularly noteworthy is the information about the technology of carving furniture in the forms of Second Rococo, in the finishing layer. Such decoration was used in new pieces of furniture as well as in old furniture from the period of Classicism, which were found in eclectic interiors. The furniture of the period under review, as well as architecture, for a long time had been considered to be second-class art. This opinion is not unfounded, however, a qualitative assessment of furniture from this period should be made. Many examples of eclectic furniture reflected the tastes of their time and the level of knowledge about the original historical styles. The material and technologies of imitated finishes as well as eclecticism itself, underwent changes over time. At its initial phase, there was a craze for walnut cutting, in the 1880s ebony wood, and mahogany in the beginning of the 20th century. Nevertheless, walnut cutting was associated with the manufacturing of furniture until the beginning of the 20th century. The furniture is very important to us as an example of the views and taste of this period, though not all of them can be considered to be masterpieces. During the restoration work, the finishing layer was often destroyed. As a result, it is very important to save the examples of finishes “under the walnut wood”.

Fundamental studies for designing insulation panels from wood shavings and filamentous fungi

The production of environmentally friendly thermal insulation boards is important for the building industry to reduce its environmental impact. The primary objective of this study was to test the feasibility of producing wood-based insulation panels as well as to use fungi as a binding agent and to explore whether a bio-based composite could be a viable alternative to the standard traditional foam insulation board and more expensive wood fibreboards (mainly available in European markets). Experiments were conducted to determine which combinations of wood fibers from selected northern tree species, wood decay fungi, and growth conditions were most suitable for panel making. The results showed that under the determined optimal growth conditions, Polyporus arcularius and Trametes suaveolens on birch wood shavings provided the best combination. Outcomes from initial physical screening tests, particularly thermal conductivity, suggested that these panels had a comparable performance to traditional insulation material.

Genetic Diversity Estimates of &amp;lt;i&amp;gt;Santalum album&amp;lt;/i&amp;gt; L. through Microsatellite Markers: Implications on Conservation

Sandalwood (Santalum album L.) is the second most expensive wood in the world. There are approximately 16 species of sandalwood (S. album, S. spicatum, S. austrocaledonicum, S. yasi, S. lanceolatum, S. ellipticum, S. macgregorii, S. insulare) occurring naturally throughout Australia, India, Indonesia, Papua New Guinea and the islands of the South Pacific. In India, S. album is found all over the country, with over 90% of the area in Karnataka, Tamil Nadu, Kerala, Andhra Pradesh and Telangana state. It is highly economic tropical tree species because of its scented heartwood and heartwood oil. Several causes have been attributed to the depletion of sandalwood population mainly amongst which theft is causing negative effect on the quality of species by constant removal of superior clones. The aim of this study was to determine the genetic diversity of S. album. For this, 177 genotypes of S. album from 14 populations of three states (Karnataka, Telangana state and Kerala) in southern India were selected. The genetic diversity and genetic structure were characterized through 25 SSR markers developed by cross amplification of different species of Sandalwood. Under this study, following genetic diversity parameters were estimated at individual level and population level; Number of alleles (Na) 9.107, Effective number of alleles (Ne) 7.56, Observed heterozygosity (Ho) 0.187, Expected heterozygosity (He) 0.861, Shannon information index (I) 2.03, F statistics 0.89, Polymorphic information content (PIC) 0.87 and Gene flow (Nm) 4.98. The estimates of gene flow among the populations of Kodada Telangana (Nm = 15.109); IWST Karnataka (Nm = 13.62) than across other geographical populations (Nm = 9.40). Analysis of molecular variance (AMOVA) revealed that 3% of the total variation was due to differences among populations and 97% due to differences within the populations. The genetic differentiation among populations (FST) 0.012 at p results showed the combined variation 82.2% of these markers. This study highlights the knowledge of genetic variation in sandalwood across the herd population of sandalwood in India. The highest range of polymorphism was detected with SSR markers developed from Osyris lanceolata compared to Santalum. austrocaledonicum, Santalum. insulare and Santalum. spicatum. This study would help in conservation of the Sandalwood populations with high profile of genetic diversity and selection of clones for genetic improvement program.

Measurements of the effects of wine maceration with oak chips using an electronic tongue.

The use of oak products as a cheaper alternative to expensive wood barrels was recently permitted in Europe, which led to a continuous increase in the use of oak chips and staves in winemaking. The feasibility of the potentiometric electronic tongue as a tool for monitoring the effects of wine maceration with oak chips was evaluated. Four types of commercially available oak chips subjected to different thermal treatments and washing procedures and their mixture were studied. Ethanolic extracts of the chips were analysed using electrospray mass spectrometry and 28 phenolic and furanic compounds were identified. The electronic tongue comprising 22 potentiometric chemical sensors could distinguish artificial wine solutions and Cabernet Sauvignon wine macerated with different types of oak chips, quantify total and non-flavonoid phenolic content, as well as the concentrations of added oak chips. Using measurements at two pH levels, 3.2 and 6.5, improved the accuracy of quantification.

Upgrading waste paper by in-situ calcium carbonate formation

Utilization of the quality-upgraded waste paper in the manufacture of paper and board will reduce the wood consumption and pulping energy. While the optical property of the fibers from recycled old newspaper is very poor, in-situ calcium carbonate formation on those fibers by injecting carbon dioxide to the mixed slurry of those pulp and calcium oxide improved their brightness. Upgrading recycled old newspaper to substitute more expensive wood furnish, such as recycled old magazine, was successfully demonstrated in the present study. This study showed that the in-situ calcium carbonate formation process improved the optical quality of the recycled old newspaper by covering colored impurities with newly formed calcium carbonate, and improved calcium carbonate retention in papermaking process by attaching them to fibers. The strength reduction by the presence of newly formed calcium carbonate in the paper was recovered by adding strength agent. High ash retention at high ash content under the strong turbulence in the modern paper mill was achieved by the application of the in-situ calcium carbonate formation method. The quality-upgrade of recycled fibers and cost saving in the manufacture of duplex paperboard were demonstrated in the mill trial.

Integrated harvesting for conventional log and energy wood assortments: a case study in a pine plantation in Western Australia

Biomass or energy wood harvesting can be integrated with conventional log harvesting (saw log or pulpwood production) to allow more cost-effective energy wood supply. The efficiency of an integrated energy wood harvesting system was evaluated and compared with conventional log harvesting in a 32-year-old Pinus radiata plantation (radiata pine) located in south-west Western Australia. The harvesting system consisted of a harvester and a forwarder. The study included two treatments: a conventional log-harvesting operation where merchantable sawlogs and pulp logs were produced at the stump by the harvester and extracted by the forwarder; and an integrated energy wood operation where the harvester produced sawlogs, pulp logs and energy wood at the stump that were extracted by the forwarder. In the integrated energy wood harvesting plot, 37 m3 ha−1 of energy wood was extracted in addition to the sawlog and pulp log volumes. Extracting the additional energy wood reduced the productivity of the forwarder and increased the cost of extraction (AU$2.7 m−3) compared with the control plot (AU$2.2 m−3). Harvesting system cost was not significantly impacted, with a cost of AU$3.18 m−3 in the control plot and AU$3.23 m−3 in the integrated energy wood harvesting plot. Diameter at breast height (DBH) was a significant factor influencing the working time of the harvester, whereas load volume, extraction distance and extraction type (sawlog, pulp logs, and pulp log/energy wood) significantly impacted forwarding time. Increasing DBH resulted in longer working cycles for the harvester. Heavier loads and longer forwarding distances increased forwarding cycle time, while extracting sawlogs was least expensive and energy wood extraction was the most expensive. The marginal cost of the energy wood was approximately AU$10.2 m−3 (AU$7.0 extraction and AU$3.2 harvesting), which is about double the cost of the sawlogs. Additional material recovered in the integrated energy wood plot resulted in less residual residues on the plot (103.2 green metric tonnes per hectare [GMt ha−1]) than the control plot (144.2 GMt ha−1).

English

Aquilaria malaccensis Lam. is commonly known as Agarwood which is distributed in the Indo-malesian genus Aquilaria of family Thymelaeaceae known to produce resin-impregnated heartwood that is fragrant and highly valuable. Agarwood is reputed to be the most expensive wood in the world. Twenty two open pollinated families in A. malaccensis were selected and evaluated for growth attributes and genetic divergence. The experiment was conducted at Forest College and Research Institute, Tamil Nadu Agricultural University; Mettupalayam situated at 11° 19’ N longitude, 76° 56’ E latitude at 300 MSL during January - December 2010. The study indicates significant differences among the selected families for various growth attributes. Among the twenty two progenies evaluated, three progenies viz., NHJA, KHOW-1 and CHEK-1 exhibited consistent superiority over growth periods for shoot length, collar diameter and number of branches. Genetic divergence studies resulted in grouping of the selected families into six clusters which indicated the existence of adequate genetic divergence. Among the clusters, cluster VI was the largest with 9 progenies while the maximum intra clusters distance was recorded in cluster V. The intra and inter cluster distance revealed that maximum inter cluster distance was recorded between cluster IV and V which indicated the presence of wide genetic distance between A. malaccensis progenies. Among the various growth attributes, number of branches contributed maximum towards genetic divergence followed by shoot length. These two characters could act as a reliable indicator for future improvement programme in this economically important species. Genetic analysis of the progenies indicated adequate variability in the population. The phenotypic co-efficient of variation (PCV) and genotypic co-efficient of variation (GCV) estimates exhibited superiority of number of branches followed by shoot length and collar diameter. In case of shoot length, collar diameter and number of branches exhibited moderate heritability. The genetic advance was high for shoot length followed by number of branches which indicated the reliability of these two parameters for inclusion in future improvement programme. Keywords: Aquilaria malaccensis, provenances, variability, heritability, genetic divergence, intra and inter cluster distance.

Poplar Wood Stain Research

With the high quality natural forest resources dwindling , since some species of wood with natural colors, such as pumping wood , ebony, rosewood , etc., not only material of high value , but also very expensive wood color . However, these are expensive and precious wood in short supply and will therefore valuable timber and wood stain to meet the market demand is similar . Low-quality hardwood stained only bright color, texture clear , three-dimensional sense of strong, but without losing the characteristics of natural wood , and organize production according to market demand the formation of industrialized products in order to improve the utilization of low-quality wood , decorative building materials to increase the existing varieties purposes. Therefore, the use of poplar simulate the market needed precious wood has important practical significance . In addition, light color white poplar wood , in the natural growth process still exists heartwood and sapwood and sooner or later material defects such as chromatic aberration , especially wood treatment is not promptly will result in discoloration, the direct use of the logs are often unable to meet the requirements of decoration . Therefore . The thicker sheet dyed precious poplar wood color , and then prepared to meet the customer poplar wood timber strength and decorative requirements, improve the added value of the use of wood , particularly after dyeing material available performance has been greatly improved.

The Agar Wood Industry: Yet to Utilize in Bangladesh

Agar wood is one of the most expensive non-timber wood products of the world. It has a series of names around the Asia and Pacific region. Bangladesh is producing three major products namely Agar-wood, Agar-oil and Agar dust/powder in Agar wood sector. It has multidimensional uses in perfume, cosmetics and medicine sector. Agar wood has traditional, religious moreover cultural uses in different parts of the world. Major Agar wood producing countries are India, Malaysia, Indonesia, Vietnam, Cambodia, Laos, Brunei, Singapore and Bangladesh. Major market/consumers of Agar wood are the Middle East (UAE, KSA and other Arabian countries) and North East Asian countries (Taiwan, Japan and Korean Republic). It has a long history in Moulvi Bazar and nearby districts of Bangladesh too. A very few constraints are creating hurdles toward flourishing this sector in Bangladesh. In this study we would be very much concentrated to identify development barriers of Agar wood sector in Bangladesh and generate few recommendations in this regard. Proper regulatory support from the government could play a very vital role to make it one of the major foreign currency earning sectors for Bangladesh.

Agarwood Production - A Multidisciplinary Field to be Explored in Bangladesh

‘Agarwood’ or ‘eaglewood’ (‘Aguru’ in Bengali) is the most expensive wood in the world, which is an occasional product of a few genera of Aquilaria and Gyrinops in the plant family Thymelaeaceae. Agar is a scented product, oleoresin, obtained from pathological conditions of the wood of live trees containing many aromatic substances. Various bacteria and fungi have been found to be associated with Agarwood formation, although it is still not absolutely clear which are important or even necessary. The quality of agar mostly depends on the plant species and the fungal species involved, as well as, certain other unknown factors. The issues are now to explore the new sources of agarwood to protect the endangered plant species, to ensure agar formation in 100% of the planted trees, upgrade in quality and most possibly quantity of agar yield per tree simultaneously minimizing the maturation time. Both physical and chemical stresses like mechanical wound and induction have long been practiced to enhance agarwood yield as well as fungal inoculation. Specificity of fungal infection is a minor criterion of agarwood formation rather than the plant’s physiological state, immune responses and presence of inducer. The agarwood production could be a multifaceted field of prospects in Bangladesh. The cultivation of new Aquilaria and Gyrinops plants and selection of appropriate inocula and inducers should be the priority objective. A multidisciplinary approach could be initiated with the experts of forestry, mycology, biochemistry and microbiology to achieve the goal.DOI: http://dx.doi.org/10.3329/ijpls.v2i1.15132 International Journal of Pharmaceutical and Life Sciences Vol.2(1) 2013: 22-32

Paper Strength Improvement by Anionic PAM and Cationic Starch Adsorbed PCC

Fillers have been used for printing paper to improve printability, sheet formation and optical properties and to reduce production costs by replacing expensive wood pulps. However, an increased filler content will decrease paper strength because filler particles interfere with fiber-fiber bonding. In order to increase filler content without sacrificing too much paper strength in high filler content papers, the surface of precipitated calcium carbonate (PCC) has been modified by adsorbing anionic polyacrylamide and cationic starch in series. The adsorbed polymer layers would enhance interactions between the filler surface and the fiber surface, improving internal bonding. It was found that the modified PCC increased paper strength at a given filler content compared to the coventional method. Negligible differences in optical properties and formation of paper, filler and fines retention and drainage on the wire section were observed between the modified and the conventional PCC. However, the decreased bulk of paper was observed when the modified PCC was used.