Hevea brasiliensis

Abstract:

In this study, supercritical carbon dioxide is chosen for the extraction and purification of omega-3 fatty acids from Hevea brasiliensis (rubber) oil because this method is environmental friendly and the extracted oil has improved nutritional and functional values. In addition, extraction using this method also can prevent organic solvent residual inside the extracted oil. During the extraction using supercritical carbon dioxide, the oil yield is increased with the increase of temperature and pressure. The best operating condition is pressure of 30 MPa, and temperature of 80 C giving 21.4714% oil yield. The analysis of fatty acids composition is using gas-chromatography. The extracted rubber seeds oil is converted to fatty acids methyl esters (FAME) make it more accessible for chromatogram analysis. From the analysis, the omega-3 fatty acids inside rubber seeds oil especially alpha-linolenic acid (ALA) is the highest compare to soybean oil and olive oil. Beside this, rubber seeds oil also contains oleic acid which is omega-9 and linoleic acid is omega-6. This is the reason rubber seeds oil can be regard as oleic-linolenic seed oil. Alpha-linolenic acid is the precursor to convert polyunsaturated fatty acids (PUFAs) to docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Oleic acid (Omega-9) has the potential for heart protection and cancer prevention but still in the state of prove. On the other hands, the linoleic acid, the element of omega-6 has the benefits to treat to treat arthritis and autoimmune disease. Therefore, rubber seeds oil has very high potential to be developed into difference products in difference industries such as pharmaceutical, cosmetics, oleochemical and foods.

Abstract

 

Soxhlet extraction which is also known as solvent extraction refers to the preferential dissolution of oil by contacting oilseeds with a liquid solvent. This is the most efficient method to recover oil from oilseeds, thus solvent extraction using hexane has been commercialized as a standard practice in today’s industry. In this study, soxhlet extraction had been used to extract the rubber seed oil which contains high percentage of alpha-linolenic acid. In addition, the different solvents will be used for the extraction of rubber seed oil such as petroleum ether, n-hexane, ethanol and water to study the best solvent to extract the rubber seed oil so the maximum oil yield can be obtained. On the other hands, the natural resource, rubber belongs to the family of Euphorbiaceae, the genus is Hevea while the species of rubber is brasiliensis. Rubber (Hevea brasiliensis) seeds are abundant and wasted because they had not been used in any industry or applications in daily life. The oil of rubber seeds had been found that contained a significant percentage of long chain polyunsaturated fatty acids especially alpha-linolenic acid (ALA). Alpha-linolenic acid is one of the important elements of omega-3 fatty acids which play important roles in human metabolism, not only playing structural roles in phospholipid bilayers but also acting as precursors to bioactive molecules. Moreover, rubber seed oil also contains a high percentage of oleic acid and linoleic acid, these all are valuable compounds. Thus, rubber seed oil can be regarded as a plant derived oleic-linolenic acid. Rubber seeds can be considered as good sources for human food, animal feed and biofuel with its high content of fat, protein, amino acids and fatty acids. Therefore, it is important to study the method of extraction to extract the valuable components from rubber seeds, purify the extracted seed oil, so that the rubber seeds oil can be utilized into difference industries pharmaceutical, food, oleochemical and cosmetics.

Abstract:

Tapping panel dryness (TPD) syndrome affecting rubber tree (Hevea brasiliensis) is known to reduce natural latex production. Its aetiology remains ambiguous despite long years of research. A low molecular weight RNA similar to viroid RNA was isolated from TPD-affected samples of rubber trees. In the present study, a modified return-polyacrylamide gel electrophoresis procedure was standardised. The viroid-like low molecular weight (LMW) RNA was found associated with leaf, bark and root tissues and rubber seedlings. The technique was employed to detect LMW RNA in different clones of rubber planted in different locations and in bud-grafted plants. The LMW RNA isolated from TPD-affected trees was found infectious on seedlings of tomato cv Pusa Ruby. The LMW RNA was reisolated from symptomatic tomato leaves but not from control plants. This is for the first time that a biotic agent, a viroid RNA, is found consistently associated with the syndrome. The technology developed can be useful to demonstrate the onset of TPD in untapped trees in the absence of other methods such as nucleic acid hybridisation.

 

The present invention relates to an isolated polypeptide for catalyzing plastidial biosynthesis of isopentenyl diphosphate, dimethylallyl diphosphate or the combination thereof in the plant of Hevea brasiliensis, comprising amino acid sequence set forth in SEQ ID NO. 2, SEQ ID NO. 4, SEQ ID NO. 6, SEQ ID NO. 8, SEQ ID NO. 10 or SEQ ID NO. 12; and a method for catalyzing the biosynthesis of isopentenyl diphosphate, dimethylallyl diphosphate or the combination thereof for enhancing the biosynthesis of natural rubber from its precursors. The present invention also relates to an isolated polynucleotide encoding the polypeptide, a recombinant gene construct comprising the polynucleotide, a transformant and a transgenic plant comprising the recombinant gene construct.

Resumo

 

http://dx.doi.org/10.5902/198050988456

Este estudo descreve a distribuição e determina a taxa anual de crescimento e a idade das árvores de Garcinia brasiliensis e de Hevea spruceana em uma floresta inundável na região de Manaus. Oito parcelas contíguas de 25 x 25 metros foram instaladas, onde todos os indivíduos das duas espécies com altura ≥ 1,0 m foram mapeados. O diâmetro, a altura das árvores e os níveis de inundação foram registrados para todos os indivíduos. A radiação fotossinteticamente ativa (RFA) foi medida em indivíduos da regeneração (≤ 10 cm diâmetro a altura do peito –dap). Foram calculadas a área basal e o volume para cada indivíduo, e determinados o padrão de crescimento e a idade das árvores utilizando métodos dendrocronológicos. Um total de 105 indivíduos foi amostrado, a maioria na classe de regeneração. Hevea spruceana apresentou o maior número de indivíduos (n=80), as maiores taxas de crescimento em dap e em altura. Garcinia brasiliensis (n=25) apresentou idade, dap e altura maiores do que Hevea spruceana. Ambas as espécies foram sujeitas a diferentes níveis de inundação e de radiação. A estrutura populacional e a distribuição dos indivíduos dessas espécies mostram ser, aparentemente, influenciadas pelas variações na topografia local em pequena escala. Os diferentes requerimentos por radiação destas espécies sugerem ocupação de diferentes nichos ecológicos.

Abstract

Summary. The oils from seeds of Hevea brasiliensis (Muëll. Arg.) cultivar RRIM 600 cultivated in Thailand (from two different sources, Chiang Rai and Surin provinces), were subjected to the evaluation of fatty acid composition, antioxidant activities, antimicrobial activities and cytotoxicity. The seed oils were extracted using n-hexane as a solvent and the major fatty acids were oleic and linoleic acids. The seed oils from two different sources similarly exhibited high capability in inhibiting scavenging DPPH radicals (95%, 87% inhibition, from Chiang Rai and Surin provinces respectively), reducing power (1.588±0.016, 1.832±0.009 mg of AAE/mL). However, moderate lipid peroxidation inhibition activity of these two seed oils were observed (24%, 28% inhibition). The cytotoxicity effect of oil was determined on human dermal fibroblast. It showed that the H. brasiliensis seed oil was not cytotoxic to human skin at >1000 μg/mL. Based on these results, it was suggested that the H. brasiliensis seed oil may be considered as a potential antioxidant candidate for topical cosmetic applications.

Industrial relevance. Natural origin raw materials have gained increasing attention for cosmetics because of their effectiveness and safety as compared to the synthetics. H. brasiliensis seed oil from this research has shown itself as a highly promising natural raw material source for cosmetic industry. It composed of skin health benefit fatty acids and has been found to exhibit high capability in inhibiting scavenging DPPH radicals. Moreover, from the cytotoxicity result, it indicated that the H. brasiliensis seed oil can safely be applied to human skin.  

Keywords. Hevea brasiliensis; seed oil; fatty acids; biological activities

Keywords

 

Hevea brasiliensis; seed oil; fatty acids; biological activities

Abstract

Biodiesel is fatty acid methyl or ethyl esters made from vegetable oils (edible and non edible) or animal fats. The objective of this research was to produce biodiesel from rubber seed by in situ method with acid catalyst with a goal for obtaining environmentally friendly alternative fuels from non edible raw material. This research focuses on influence of reaction time, concentration of acid catalyst and ratio raw material to methanol. The first stage was carried out in order to get reaction time based on the density and viscosity of mixture produced. In this process H2SO4 0.5% (v/v) was used as catalyst and ratio of raw material to methanol (1:2). The experiments were conducted by investigating the catalyst concentration in range 0.1-1%(v/v) and ratio of raw material to methanol in range 1:1.5-1:3. The research method included, the preparation of samples, biodiesel production, biodiesel separation, and biodiesel characterization i.e density, viscosity, GC analysis, acid value and Iodine number. The results shows that the operation time for biodiesel production by in situ method with acid catalyst was 120 minutes and the yield of Fatty Acid Methyl Ester (FAME) obtained was at 91,05%.

Abstract

 

Rubber clones of Indonesian Rubber Research (IRR) 200 series have been produced from intensive breeding program started in 1985. Some clones showed superior characteristics such as high latex yielding, vigorous, and disease resistant. This study aimed to test their performances in a field trial conducted since 1999 at Sungei Putih Experimental Garden, North Sumatra. The experiment was designed in a randomized block, using twelve IRR clones as treatment and PB 260 clone as control, three replications. Planting distance was 5 m x 4 m and plot size was 10 rows x 50 trees. Observations were made on girth size of the 2, 3 and 4 year-old trees, dry rubber yield following the 1/2S d/2 and 1/2S d/3.ET2.5% tapping systems, bark thickness, rings number and diameter of latex vessels, as well as leaf fall diseases intensities of 3-5 year-old trees. The results showed four IRR 200 clones, i.e. IRR 207, IRR 208, IRR 211 and IRR 220 produced high latex. Using the 1/2S d/2 tapping system, three clones with highest dry rubber yield were obtained, namely IRR 208 (49.8 g tree-1 tapping-1 or g t-1 t-1), IRR 211 (48.8 g t-1 t-1) and IRR 220 (52.0 g t-1 t-1), whereas that using the 1/2S d/3. ET2.5% tapping system, their yields were 63.2 g, 64.3 g, and 66.2 g t-1 t-1, respectively. At four year-old, these clones had girth size of 41.4-51.0 cm, girth increment 9.7-11.6 cm year-1, bark thickness 6.3-7.2 mm, latex vessel rings number 6.8-7.0, and diameter of latex vessels 23.75-26.57 mm. All of the clones were moderately resistant to Colletotrichum, Oidium and Corynespora leaf fall diseases. This study suggests that IRR 207, IRR 208, IRR 211 and IRR 220 rubber clones are suitable for commercial stake holders and the recommended tapping system is 1/2S d/3.ET2.5%.

The present invention discloses an isolated polynucleotide encoding an enzyme for catalyzing cytosolic biosynthesis of isopentenyl diphosphate, dimefhylallyl diphosphate or the combination thereof in the plant of Hevea brasiliensis, comprising nucleotide sequence set forth in SEQ ID NO. 1, SEQ ID NO. 3, SEQ ID NO. 5, SEQ ID NO. 7, SEQ' ID NO. 9 or any complementary sequence thereof; and a method for enhancing cytoplasmic availability and functionality of the enzyme, comprising the steps of predicting catalytic domain, signal peptide or membrane-spanning domain of the enzyme; introducing a point mutation to the predicted catalytic domain, signal peptide or membrane-spanning transmembrane domain; and expressing the mutated catalytic domain, signal peptide or membrane-spanning transmembrane domain in a plant cell, tissue or organ of Hevea brasiliensis. The present invention also relates to an isolated polypeptide encoded by the polynucleotide, a recombinant gene construct comprising the polynucleotide, a transformant and a transgenic plant comprising the recombinant gene construct, with enhanced production of cytosolic isoprenoid towards rubber production.

The present invention relates to an isolated polynucleotide encoding an enzyme for catalyzing biosynthesis, conversion or utilization of prenyl-pyrophosphate for rubber biosynthesis in the plant of Hevea brasiliensis, comprising nucleotide sequence set forth in SEQ ED NO. 1, SEQ ID NO. 3, SEQ ID NO. 5, SEQ ID NO. 7, SEQ ID NO. 9 or any complementary sequence thereof. The present invention also relates to an isolated polypeptide encoded by the polynucleotide; a recombinant gene construct comprising the polynucleotide; a transformant; and a transgenic plant comprising the recombinant gene construct, with enhanced biosynthesis and accumulation of polyisoprenoids; as well as a method for enhancing biosynthesis and accumulation of polyisoprenoids comprising the steps of cloning the gene construct comprising the polynucleotide and expressing the gene construct in a host cell.

Abstract

The most effective control of a weed flora consisting mainly of Digitaria sanguinalis, Cassia tora, Ipomoea spp., Richardia brasiliensis and Sida spp. was obtained with 5 kg napropamide + 0.8 kg simazine/ha. Control was long lasting and no injury to rubber trees was observed.