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1.
Agarwood is a valuable oleoresin obtained from wounded tree of various genus of Thymelaeaceae family especially from Aquilaria species. Agarwood is regarded as most treasured non-timber forest product used in fragrances as well as medicines. Quality of agarwood plays an important role to define its commercial value. Different countries use different grading pattern to define the quality of agarwood. More than 250 compounds have been identified so far, mostly sesquiterpenoids, chromones and volatile aromatic compounds. GC–MS is the considered as a best method for the identification of chemical profile of the agarwood by various authors. Present review discusses the various methods used to determine quality of agarwood and chemical constituents of infected agarwood tree.  相似文献   

2.
Spatial, Temporal, and Economic Constraints to the Commercial Extraction of a Non?CTimber Forest Product: Copaíba (Copaifera spp.) Oleoresin in Amazonian Reserves. The increasing prevalence of government?C and NGO?Csponsored programs to encourage commercial non?Ctimber forest product (NTFP) extractivism in the humid tropics has highlighted the need for ecological and socioeconomic appraisal of the viability of extractive industries. We adopted a novel integrative approach to examine NTFP resource potential and produced credible landscape?Cscale estimates of the projected value of an economically important Amazonian NTFP, the medicinal oleoresin of Copaifera trees, within two large contiguous extractive reserves in Brazilian Amazonia. We integrated results derived from previous spatial ecology and harvesting studies with socioeconomic and market data, and mapped the distribution of communities within the reserves. We created anisotropic accessibility models that determined the spatial and temporal access to Copaifera trees in permanently unflooded (terra firme) and seasonally flooded (várzea) forests. Just 64.9?% of the total reserve area was accessible, emphasizing the distinction between the actual resource stock and that which is available to extractors. The density of productive tree species was higher in the várzea forests, but per?Ctree productivity was greater in the terra firme forests, resulting in similar estimates of oleoresin yield per unit area (64?C67?ml?ha?C1) in both forest types. A greater area of the várzea forests was accessible within shorter travel times of ??250 minutes; longer travel times allowed access to increasingly greater volumes of oleoresin from the terra firme forests. The estimated total volume of oleoresin accessible within the two reserves was 38,635 liters for an initial harvest, with projected offtake for a subsequent harvest falling to 8,274 liters. A household that extracted just 2 liters of oleoresin per month could generate 5?% of its mean income; market data suggested that certification could increase the value of the resource fivefold. Our approach is valuable in that it incorporates a range of methodologies and quantitatively accounts for the numerous constraints to the commercial viability of NTFP extraction.  相似文献   

3.
The aims of this study was to evaluate the effects of oil-resin of Copaiba (Copaifera duckei Dwyer), aired in vaginal cream on the reproductive performance of female rats (Rattus norvegicus). To determine the components of the C. duckei oleoresin, gas chromatography coupled with mass spectrometry (CG-MS) was used, and considering the trans-caryophyllene sesquiterpene as a phytochemical marker in the oleoresin. Due to the extensive use of copaiba oleoresin in the suppository form for gynecological infections, an evaluation was carried out on the effects of copaiba oleoresin (Copaifera duckei Dwyer), delivered in a vaginal cream, on the reproductive performance of female Wistar rats. For this purpose, three groups (n = 5-6/group) of female rats were treated as follows: 1 - vaginal cream of copaiba oleoresin (28.6 mg/kg), 2 - base vaginal cream and 3 - control (physiological saline 0.9%), administered intravaginally, for 30 days before pregnancy, and from day zero to day 20 during pregnancy. Laparotomy was performed on the 21st day of pregnancy, followed by the determination of reproductive variables: number of live and dead fetuses, mass of the fetuses and placentas, number of implantations and resorptions, number of corpora lutea, pre- and post-implantation loss, and analyses of the fetuses with regard to external and internal anomalies and/or malformations (skeletal and visceral). The trans-caryophyllene present in the sample is suggested as a phytochemical marker and the results of this study demonstrate an absence of maternal toxicity and foetotoxicity embryofoetotoxicity at the dose administered, corresponding to ten times the recommended dose for use in humans. Accordingly, no significant statistical difference was observed between the treated and control groups, for the variables analyzed.Thus, it is concluded that the vaginal cream containing 2.5% copaiba oleoresin is safe during gestation, in female rats (Rattus norvegicus) of the Wistar strain.  相似文献   

4.
Sustainable harvesting practices are important for conserving plant species and their habitats, but also the livelihoods of those that depend on them. Aloe ferox, a valuable natural resource harvested for its leaves, is the focus of a recent rural development initiative in the Eastern Cape of South Africa. This has the potential to benefit poor residents through a high-value, sustainable, export market. We characterize the social and ecological components of the system, in order to evaluate the potential for effective natural resource management. We interviewed aloe tappers to obtain information on their dependence on the A. ferox industry and harvesting practices. We assessed the harvesting pressure on A. ferox populations, sampling plants at three plots positioned along each of four transects at distances of 1.5, 3.45, and 7 km from the factory, grouping plants into two size classes: small (height <0.5 m) and large (>0.5 m). We investigated the influence of proximity to the factory and plant size class on the likelihood and intensity of harvest. The majority of aloe tappers were women, unemployed, and in receipt of government welfare grants, and the main reason for harvesting A. ferox was to generate a cash income for their daily needs. Training guidelines did not appear to be followed, with aloe tappers leaving on average 6 leaves, rather than the recommended 18–20 leaves, allowing insufficient time to pass between harvesting episodes and harvesting outside of the prescribed wetter periods. In line with training guidelines, aloe tappers were targeting larger plants; however, against recommendations, smaller plants were also regularly harvested. Harvesting pressure decreased with increasing distance from the factory. We discuss requirements to ensure A. ferox is harvested at sustainable levels in the region, particularly in light of a possible regional roll out of the program, and provide recommendations for regulating use and better training.  相似文献   

5.
6.
Introduction – Phytochemical and biological studies carried out on Copaifera species showed that their oleoresins and isolated compounds have various biological activities. Objective – The aims of this work were (i) to analyse the Copaifera oleoresin by gas chromatography–mass spectrometry, (ii) to isolate the diterpenic acids from this oleoresin by high‐speed countercurrent chromatography (HSCCC) and (iii) to determine the rhodamine 6G Pdr5p activity of these acids. Methodology – HSCCC was used for the preparative separation of the diterpenes. Spectroscopic methods were used to establish their identity. Results – The gas chromatogram of the oleoresin showed approximately 30 compounds. The two major ones, kaur‐16‐en‐18‐oic and polyalthic acids, were isolated in high purity. Kaur‐16‐en‐18‐oic acid exhibited the highest rodomine 6G Pdr5p activity among the tested compounds. Conclusion – HSCCC was shown to be a quick and effective tool in the isolation and purification of diterpenes from Copaifera oleoresin. This is the first report on the use of HSCCC for the fractionation of an oleoresin from Copaifera and the isolation of diterpenes therein. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

7.
Methylammonium cannot be used as a nitrogen source by the green alga Chlamydomonas reinhardii and, like ammonia, caused the repression of nitrate reductase without affecting the photosynthetic activity. Glutamine synthetase catalyzed the conversion ofmethylammonium to a single product, identified as γ-N-methylglutamine, which accumulated in the cells. Derepression of nitrate reductase was accompanied by a decrease in the intracellular concentration of methylammonium and a concomitant accumulation of γ-N-methylglutamine inside the cells. These facts strongly suggest that ammonium (methylammonium) per se, and not a product of its metabolism, is the co-repressor of nitrate reductase in C. reinhardii  相似文献   

8.
9.
The antiradical properties of three samples of ginger (Zingiber officinale R.)—juice from fresh rhizome, essential oil, and extracts (oleoresin)—were studied and compared with the properties of synthetic antioxidant ionol (butylatedhydroxy-toluene, BHT). Reaction antioxidants with stable free 2,2-diphenyl-1-picrylhydrozyl radicals were used as model systems. DPPH equivalents per gram of ginger sample, EC50, and antiradical efficiency (AE) were determined. The EC50 and AE values for ginger oleoresin and BHT were similar. They were the same as those of highly active natural antioxidants, and the values for essential oil and ginger juice were lower by two orders of magnitude. On the base of kinetic parameters, the ginger samples may belong to antiradical compounds with prolonged action.  相似文献   

10.
Resin tappers in Sumatra induce resin flow in Shorea javanica by first opening vertical rows of small (3 cm) holes in the tree trunk. After 6–12 mo, larger (10–15 cm) holes are opened between the rows of small holes for resin harvest. Informants reported that opium applied to trees increased resin yields. Application of 10% 2-chloroethylphosphonic acid to artificial trunk wounds ofS. javanica production trees increased resin yields by 110% relative to controls in 72-h trials. Wounds of previously untapped trees exuded no resin in response to the same treatment.  相似文献   

11.
12.
The aim of this work is to establish the difference among several Spanish Pinus pinaster provenances, on the basis of its oleoresin chemical composition.Oleoresin of five P. pinaster provenances in three experimental plantation areas has been studied. Monoterpenes, sesquiterpenes, neutral diterpenes and resin acids are the main components. The compounds allowing the establishment of differences between provenances are isopimaric acid and α-pinene, whereas the differentiation between plots is established by pimaric acid and noracid 2. Provenances best differentiated are Ponteareas (Atlantic group) and Cómpeta (Maghrebian group).  相似文献   

13.
Apart from addressing humanity’s growing demand for fuels, pharmaceuticals, plastics and other value added chemicals, metabolic engineering of microbes can serve as a powerful tool to address questions concerning the characteristics of cellular metabolism. Along these lines, we developed an in vivo metabolic strategy that conclusively identifies the product specificity of glycerate kinase. By deleting E. coli’s phosphoglycerate mutases, we divide its central metabolism into an ‘upper’ and ’lower’ metabolism, each requiring its own carbon source for the bacterium to grow. Glycerate can serve to replace the upper or lower carbon source depending on the product of glycerate kinase. Using this strategy we show that while glycerate kinase from Arabidopsis thaliana produces 3-phosphoglycerate, both E. coli’s enzymes generate 2-phosphoglycerate. This strategy represents a general approach to decipher enzyme specificity under physiological conditions.  相似文献   

14.
Siberian pine (Pinus sibirica), also known as Siberian cedar pine and Siberian cedar, is an important plant that has been long used as a source of natural compounds and materials (wood, needles, soft resin, turpentine, colophony). Its chemical composition has been studied well enough; however, to our surprise, no articles that compile the phytochemical data have been published so far. Presumably, this is due to the fact that most of the studies were published in journals difficult to access and not indexed by search systems. This review, for the first time, presents a systematic compilation of available data of secondary metabolites occurring in the needles, shoots, bark, wood, seeds, and oleoresin of Pinus sibirica.  相似文献   

15.
萧氏松茎象危害与松树松脂量关系研究初报   总被引:6,自引:1,他引:5  
萧氏松茎象HylobitelusxiaoiZhang是近年来暴发性松树害虫 ,主要危害 3种松树 :湿地松 (PinuselliottiiEngelm)、火炬松 (P .taeda)、马尾松 (P .massoniaanaLamb) ,其中以湿地松受害最为严重。为明确萧氏松茎象的危害与松脂流量的关系 ,作者对萧氏松茎象危害前后 3种松树 (湿地松、马尾松、火炬松 )松脂流量变化进行了研究。结果显示 ,在松树受害植株和未受害植株间松脂总流量间存在一定差异 ,其中以马尾松松脂流量变化最大 ,对受害株和未受害株松脂流量t-测验 ,差异达到显著水平 ;而湿地松和火炬松松脂总流量在受害植株和未受害植株间没有显著差异。对上述 3种松树松脂流量随时序动态变化的分析显示 ,松脂流量在 1年中以 5月到 6月之间为松脂流量高峰期 ,此后逐渐下降 ,到 3月中旬以后松脂流量又开始上升。就松脂流量时序动态而言 ,萧氏松茎象为害对马尾松松脂流量影响最大 ,对其它2个松树影响不明显。另外 ,不同松树树种在松脂流量及其时序动态上也存在一定差异 ,其中以马尾松脂流量较高。  相似文献   

16.
Cell-free extracts from Pinus ponderosa Lawson (ponderosa pine) and Pinus sylvestris L. (Scotch pine) wood exhibited high levels of monoterpene synthase (cyclase) activity, whereas bark extracts of these species contained no detectable activity, and they inhibited cyclase activity when added to extracts from wood, unless polyvinylpyrrolidone was included in the preparation. The molecular mass of the polyvinylpyrrolidone added was of little consequence; however, polyvinylpolypyrrolidone (a cross-linked insoluble form of the polymer) was ineffective in protecting enzyme activity. Based on these observations, methods were developed for the efficient extraction and assay of monoterpene cyclase activity from conifer stem (wood and bark) tissue. The level of monoterpene cyclase activity for a given conifer species was shown to correlate closely with the monoterpene content of the oleoresin and with the degree of anatomical complexity of the specialized resin-secreting structures. Cyclase activity and monoterpene content were lowest in the stems of species containing only isolated resin cells, such as western red cedar (Thuja plicata D. Don). Increasing levels of cyclase activity and oleoresin monoterpenes were observed in advancing from species with multicellular resin blisters (true firs [Abies]) to those with organized resin passages, such as western larch (Larix occidentalis Nutt.), Colorado blue spruce (Picea pungens Engelm.) and Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco). The highest levels of cyclase activity and oleoresin monoterpenes were noted in Pinus species that contain the most highly developed resin duct systems. The relationship between biosynthetic capacity, as measured by cyclase activity, monoterpene content, and the degree of organization of the secretory structures for a given species, may reflect the total number of specialized resin-producing cells per unit mass of stem tissue.  相似文献   

17.
Chloroplasts isolated from sweetclover leaves contain an enzyme which converts trans-[3-14C]cinnamic acid to 2-hydroxy-trans-[3-14C]cinnamic (o-coumaric) acid. The identity of the product has been verified by recrystallization with unlabeled o-coumaric acid to constant specific activity, and by gas-liquid cochromatography of unlabeled o-coumaric acid and the radioactive product.The enzyme has an optimum of pH 7.0 and its activity can be enhanced ~ 4-fold by adding 4 mm glucose-6-phosphate to the reaction mixture. Light can replace glucose-6-phosphate, presumably as a source of reducing power required for the hydroxylation system. It was found that approximately 50% of the hydroxylase activity is bound to the lamellar membranes, from which it can be released by sonication.  相似文献   

18.
Plant-derived natural active products have attracted increasing attention for use in flavors and perfumes. These compounds also have applications in insect pest control because of their environment-friendly properties. Holy basil (Ocimum sanctum), a famous herb used in Ayurveda in India, is a natural source of medical healing agents and insecticidal repellents. Despite the available genomic sequences and genome-wide bioinformatic analysis of terpene synthase genes, the functionality of the sesquiterpene genes involved in the unique fragrance and insecticidal activities of Holy basil are largely unknown. In this study, we systematically screened the sesquiterpenoid biosynthesis genes in this plant using a precursor-providing yeast system. The enzymes that synthesize β-caryophyllene and its close isomer α-humulene were successfully identified. The enzymatic product of OsaTPS07 was characterized by in vivo mining, in vitro reaction, and NMR detection. This product was revealed as (−)-eremophilene. We created a mutant yeast strain that can achieve a high-yield titer by adjusting the gene copy number and FPP precursor enhancement. An optimized two-stage fed-batch fermentation method achieved high biosynthetic capacity, with a titer of 34.6 g/L cyclic sesquiterpene bioproduction in a 15-L bioreactor. Further insect-repelling assays demonstrated that (−)-eremophilene repelled the insect pest, fall leafworm, suggesting the potential of (−)-eremophilene as an alternative to synthetic chemicals for agricultural pest control. This study highlights the potential of our microbial platform for the bulk mining of plant-derived ingredients and provides an impressive cornerstone for their industrial utilization.  相似文献   

19.
Lactococcus lactis grows homofermentatively on glucose, while its growth on maltose under anaerobic conditions results in mixed acid product formation in which formate, acetate, and ethanol are formed in addition to lactate. Maltose was used as a carbon source to study mixed acid product formation as a function of the growth rate. In batch and nitrogen-limited chemostat cultures mixed acid product formation was shown to be linked to the growth rate, and homolactic fermentation occurred only in resting cells. Two of the four lactococcal strains investigated with maltose, L. lactis 65.1 and MG1363, showed more pronounced mixed acid product formation during growth than L. lactis ATCC 19435 or IL-1403. In resting cell experiments all four strains exhibited homolactic fermentation. In resting cells the intracellular concentrations of ADP, ATP, and fructose 1,6-bisphosphate were increased and the concentration of Pi was decreased compared with the concentrations in growing cells. Addition of an ionophore (monensin or valinomycin) to resting cultures of L. lactis 65.1 induced mixed acid product formation concomitant with decreases in the ADP, ATP, and fructose 1,6-bisphosphate concentrations. ADP and ATP were shown to inhibit glyceraldehyde-3-phosphate dehydrogenase, lactate dehydrogenase, and alcohol dehydrogenase in vitro. Alcohol dehydrogenase was the most sensitive enzyme and was totally inhibited at an adenine nucleotide concentration of 16 mM, which is close to the sum of the intracellular concentrations of ADP and ATP of resting cells. This inhibition of alcohol dehydrogenase might be partially responsible for the homolactic behavior of resting cells. A hypothesis regarding the level of the ATP-ADP pool as a regulating mechanism for the glycolytic flux and product formation in L. lactis is discussed.  相似文献   

20.
The introduction of paraquat (l, 1‘-dimethyl-4,4‘-bipyridylium ion) into the transpiration stream of young slash pine (Pinus elliottii Engelm.) trees significantly enhances oleoresin biogenesis and results in localized resin soaking in treated portions of the bole. All affected cells of the xylem symplast, including those not directly associated with resin ducts, begin to synthesize excessive oleoresin and secrete or lose it initially through pits into the lumen of contiguous tracheids. Oleoresin is observed in plastids, mitochondrial envelopes, vacuoles, and ER cisternae in both control and treated trees. Cells near the site of paraquat treatment show extreme damage to membrane integrity, depletion of starch, and loss of cellular organization. The transport of oleoresin across cellular membranes does not appear to be achieved by transporting vesicles or by a mechanism involving exocytosis. Although oleoresin is observed in various cellular organelles, it is unclear if its synthesis occurs in association with these organelles or whether this compartmentation results from random contact and solubilization of this lipophilic material in the membranes of different organelles.  相似文献   

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