Taxus Wallichiana Research Articles

Eco Stoichiometric Characteristics of Soil Plant System of <i>Taxus wallichiana</i> under Multi factor Driving

Eco Stoichiometric Characteristics of Soil Plant System of <i>Taxus wallichiana</i> under Multi factor Driving

Development of hyperspectral indices for anti-cancerous Taxol content estimation in the Himalayan region

Monitoring and management of rare and economically important species in the highly complex terrain are challenging and thus need advanced technological development. In this study, the hyperspectral radiometer data of Taxus wallichiana were acquired at highly complex terrain of the Pindari region of the Himalaya and processed by using several sophisticated algorithms to deduce Taxol content in the plants. The spectroradiometer data were denoised through three different types of smoothing filters such as Average Mean, Savitzky Golay, and Fast Fourier Transform (FFT) followed by feature selection for allocation of best bands for Taxol content estimation. The results showed that the Average Mean filter in combination with feature selection performed best for Taxol spectral indices generation, model development, and Taxol content prediction. The best model showed a correlation of 0.719 with a relative root mean square error (RMSEr) value of 0.678 for Taxol content prediction.

Potentiality of income generation through Non-timber Forest Products: A case study from the Sallipatan Trishakti Community Forest, Bajhang district, Nepal

Non-timber Forest Products are the major source of livelihood support for rural communities in Nepal. A case study was performed to determine the potentiality of income generation through Non-timber Forest Products (NTFPs) in the Sallipatan Trishakti community forest of Bajhang district, Nepal from February to April 2020. The Questionnaire surveys, key informant surveys, focus group discussions and forest resource inventory have been used for the data collection. A total of 37 species of NTFPs from 31 families were identified out of which only five species were found to have high market potential. Xanthoxylum armatum (Timur), Phyllanthus emblica (Amala), and Cinnamomum tamala (Tejpat) were found in good frequency and have a good market but the yearly earnings and the number of households involved were low. Bergenia ciliate (Pakhanbed), Valeriana jatamansi (Sugandhawal), and Rhododendron arboretum (Lali gurans) were present in high density in the forest and have high market value but locals didn’t prefer and market them due to lack of knowledge and processing technology. Pinus roxburghii, Myrica esculenta, Among the total respondents, 59% collect NTFPs for household purposes, 30% for selling purposes, and 11% for traditional uses. Swertia chirayita, Rhododendron arboretum, Cinnamomum tamala, Drepanostachyum sps., Asparagous racemous and Taxus wallichiana would have the potentiality for small scale business from the community forest if they were promoted and managed properly.

Respiratory temperature responses of tropical conifers differ with leaf morphology

Abstract Photosynthetic traits suggest that shade tolerance may explain the contrasting success of two conifer taxa, Podocarpaceae and Pinaceae, in tropical forests. Needle‐leaved species from Pinus (Pinaceae) are generally absent from tropical forests, whereas Pinus krempfii, a flat‐leaved pine, and numerous flat‐leaved Podocarpaceae are abundant. Respiration (R) traits may provide additional insight into the drivers of the contrasting success of needle‐ and flat‐leaved conifers in tropical forests. We measured the short‐term respiratory temperature (RT) response between 10 and 50°C and foliar morphological traits of three needle‐ and seven flat‐leaved conifer species coexisting in a tropical montane forest in the Central Highlands of Vietnam containing notable conifer diversity. We fit a lognormal polynomial model to each RT curve and extracted the following three parameters: a (basal R), and b and c (together describing the shape of the response). Needle‐leaved species (Pinus kesiya, Pinus dalatensis and Dacrydium elatum) had higher rates of area‐based R at 25°C (R25‐area) as well as higher area‐based modelled basal respiration (a) than flat‐leaved species (P. krempfii, Podocarpus neriifolius, Dacrycarpus imbricatus, Nageia nana, Taxus wallichiana, Keteeleria evelyniana and Fokienia hodginsii). No significant differences were found between needle‐ and flat‐leaved species in mass‐based R25 (R25‐mass) or in the shape of the RT response (b and c); however, interspecific differences in R25‐mass, R at nighttime temperature extremes (R4.1 and R20.6) and leaf traits were apparent. Differences in R25‐area and a suggest that needle‐leaved foliage may be more energetically costly to maintain than flat‐leaved foliage, providing new insight and additional support for the hypothesis that shade tolerance is an important driver of Podocarpaceae success and Pinaceae absence in the majority of tropical forests. Interspecific differences in R25‐mass and leaf traits highlight that varying ecological strategies are employed by conifers to coexist and survive in the Central Highlands of Vietnam. Ultimately, these data further our understanding of current conifer biogeographical distributions and underscore the need for additional studies to elucidate the effects of extreme temperature events on the continued survival of conifers in this unique forest. A free Plain Language Summary can be found within the Supporting Information of this article.

Chromosome-level genome of Himalayan yew provides insights into the origin and evolution of the paclitaxel biosynthetic pathway

Taxus, commonly known as yew, is a well-known gymnosperm with great ornamental and medicinal value. In this study, by assembling a chromosome-level genome of the Himalayan yew (Taxus wallichiana) with 10.9 Gb in 12 chromosomes, we revealed that tandem duplication acts as the driving force of gene family evolution in the yew genome, resulting in the main genes for paclitaxel biosynthesis, i.e. those encoding the taxadiene synthase, P450s, and transferases, being clustered on the same chromosome. The tandem duplication may also provide genetic resources for the nature to sculpt the core structure of taxoids at different positions and subsequently establish the complex pathway of paclitaxel by neofunctionalization. Furthermore, we confirmed that there are two genes in the cluster encoding isoenzymes of a known enzyme in the paclitaxel biosynthetic pathway. The reference genome of the Himalayan yew will serve as a platform for decoding the complete biosynthetic pathway of paclitaxel and understanding the chemodiversity of taxoids in gymnosperms.

Development of hairy root culture in Taxus baccata sub sp wallichiana as an alternative for increased Taxol production

The Himalayan Yew or Taxus baccata sub sp. wallichiana is the native of the Temperate belt of Himalayas known widely for its ethnomedical properties and especially for the production of an anti-cancerous compound Taxol but since the plant is an understory and in low population size, the production of Taxol in nature is very poor so it cannot meet the high demand of Taxol for medical use. Hairy root culture is known for its genetic and physiochemical stability and increased production of secondary metabolites as compared to cell suspension culture and with the use of low frequency sonication for 1–2 min, the rate of transformation can be increased thereby induing more hairy roots. In our study, when the combination of low frequency sonication for production of hairy roots was used it helped in development of the hairy root culture of Taxus baccata sub sp. wallichiana as an alternative for increased Taxol production. It was seen that the hairy root induction from the explants emerged when an effective co– infection method in presence of acetosyringone with sonication for 60 s was done. The increase in hairy root biomass was further done for 16 weeks in root induction media that was without acetosyringone. The methanolic extract of the biomass when quantified for total Taxol content produced around 12 mg of Taxol per gram of hairy root biomass of Taxus baccata sub sp. wallichiana which is 79% more than the natural production of 0.15 mg per gram of bark stating a possible alternative for Taxol production commercially in a large amount.

Assessing species abundance and habitat preferences in a part of Nanda Devi Biosphere Reserve, western Himalaya

Present study is an attempt to understand the plant species abundance and habitat preferences using multivariate method in Nanda Devi Biosphere Reserve (NDBR), in western Himalaya. Soil, altitude, slope and differences are reported to be the most important parameters shaping the plant community in the mountains. Two representative areas i.e., Pindari–Sunderdhunga–Kafni site (PSK) of Kumaun region and Lata–Tolma–Phagti site (LTP) of Garhwal region with nineteen forest communities in buffer zone of NDBR have been investigated. All the forest communities were analyzed for assessing community composition and species density in relation to environmental variables. Out of 451 plant species recorded from the study sites, there was a dominance of herbs (70.5%) followed by shrubs (17.7%) and trees (11.8%). Maximum tree density in PSK and LTP sites was recorded in Betula utilis (535 ind ha−1) and mixed T. wallichiana–A. pindrow (1211 ind ha−1) communities respectively. The disturbed habitats in low to mid elevation areas are represented by low canopy cover and high seedling density in PSK site and high non-native species density in LTP site. Both the study sites are dominated by Betula utilis, Taxus wallichiana, Abies pindrow in high elevation areas securing high density of native and endemic species. Habitat preferences of different important species indicate their range of distribution and choice of association with other species.

Auxin supplemented Hoagland′s medium exhibits potentials of conserving endangered Taxus baccata subsp wallichiana

Himalayan yew (Taxus baccata subsp wallichiana) produces Taxol (an anticancer drug) and therefore is of commercial importance. Yew is slow growing, exhibits poor regeneration rate, low survival percentage and has long seed dormancy period low viability potential. Overexploitation of Taxus has forced scientist to think of alternative measures for growing Taxus without compromising with Taxol extraction from the plant. Hydroponics is a good method for growing plants and the same was targeted in our study. The design was to grow yew cuttings in Hoagland’s medium as nutrition medium for growing Taxus with auxin (NAA, IAA, and IBA) in 250 mg/l, 500 mg/l, 1000 mg/l, 2000 mg/l, and 5000 mg/l concentration supplemented in the medium for 16 weeks. The control plants died after 16 weeks but the auxin supplemented medium kept yew cuttings alive and resulted in increase in shoot length. On average, the yew cuttings gained an increase of more than 80 % in yew cuttings for 16 weeks. From the experiment, it was deduced that auxin in the range of 250–2000 mg/l enhances the shoot length better than higher concentration. It was seen from the comparative data between eight to 16 weeks that the percentage of increase in height of yew cutting at 5000 mg/l is 7 % for IBA, 17 % for IAA and 14 % for NAA, clearly depicting that IAA and NAA are better Auxins for eliciting growth of Yew in stress condition. This strategy can work for the conservation of Taxus baccata for its ex situ conservation.

Annulohypoxylon sp. strain MUS1, an endophytic fungus isolated from Taxus wallichiana Zucc., produces taxol and other bioactive metabolites.

The online version contains supplementary material available at 10.1007/s13205-021-02693-z.

New Distributional Records of the Himalayan Yew in North Western Himalaya, India-A Consequence of Climate Change

Biological and ecological responses are apparent throughout the globe on plants and animals. In Himalaya, climate change greatly affected distribution and abundance of plants along latitude and elevation because temperature increased 2-5 times more than global average rate. Many treeline, ecotone and community studies are evidence to it, climatic conditions shape the ranges and distribution of species in Himalaya. The Himalayan Yew ( Taxus wallichiana Zucc.) is an endangered native high value medicinal plant, also shows the biological and ecological responses in the Himalayan region in context to global warming. The present study, investigated the distribution and abundance of Himalayan Yew in the Lahaul valley of the cold region.

Influence of altitude on secondary metabolites, antioxidants, and antimicrobial activities of Himalayan yew (Taxus wallichiana)

The present study aimed to investigate the impact of altitude on the bioactive compounds, antioxidants, and antimicrobial activity of Taxus wallichiana. Plant needles were collected from three different altitudes representing different environmental conditions and investigated for secondary metabolites such as phenol, flavonoid, flavanol, taxol, and tannin along with antioxidant and antimicrobial activity. Results revealed that the investigated Taxus wallichiana populations have accumulated varied amount of studied bioactive compounds. Total phenol, flavonoid content, and bioactive compounds such as gallic acid, ascorbic acid, and quercetin showed significant positive correlation with altitude (p < 0.01) and antioxidant activity (DPPH, ABTS). By contrast, tannin, taxol, and flavanol content of the plant did not show any relation with altitude, but showed positive significant correlation with antibacterial activity. The results suggest that the accumulation of bioactive compounds in Taxus wallichiana needles depend on the edaphic and climatic conditions of the habitat and plant antimicrobial activity is mainly due to taxol, flavanol, and tannin compounds.

α-Conidendrin inhibits the expression of intercellular adhesion molecule-1 induced by tumor necrosis factor-α in human lung adenocarcinoma A549 cells

α-Conidendrin is a lignan isolated from Taxus wallichiana and other species. In the present study, we demonstrated that α-conidendrin inhibited the cell-surface expression of intercellular adhesion molecule-1 (ICAM-1) induced by tumor necrosis factor-α (TNF-α) at an IC50 value of 40–60 μM in human lung adenocarcinoma A549 cells. α-Conidendrin decreased ICAM-1 protein and mRNA expression levels at concentrations of 40–100 μM in TNF-α-stimulated A549 cells. The TNF-α-induced mRNA expression of vascular cell adhesion molecule-1, E-selectin, and cyclooxygenase-2 was also reduced by α-conidendrin. In the TNF-α-induced nuclear factor κB (NF-κB) signaling pathway, α-conidendrin did not influence the translocation of the NF-κB subunit RelA from the cytoplasm to the nucleus at concentrations up to 100 μM. A chromatin immunoprecipitation assay revealed that α-conidendrin at 100 μM reduced the binding of RelA to the ICAM-1 promoter in response to a stimulation with TNF-α. Collectively, these results indicated that α-conidendrin interfered with the DNA binding of RelA to the ICAM-1 promoter, thereby reducing ICAM-1 transcription.

Evaluation of antimicrobial, antioxidant and cytotoxic properties of bioactive compounds produced from endophytic fungi of Himalayan yew ( Taxus wallichiana) in Nepal.

Background: Endophytic fungi are largely underexplored in the discovery of natural bioactive products though being rich sources of novel compounds with promising pharmaceutical potential. In this study, Taxus wallichiana, which has huge medicinal value, was investigated for its endophytic diversity and capability to produce bioactive secondary metabolites by analyzing antioxidant, antimicrobial and cytotoxic properties. Methods: The endophytes were identified by ITS-PCR using genomic DNA samples. The secondary metabolites were extracted by solvent extraction method using ethyl acetate. The antioxidant activity was analyzed by Thin Layer Chromatography, Total Phenol Content (TPC), Total Flavonoid Content (TFC) and DPPH assay, and the antimicrobial activity was analyzed by agar-well diffusion method. Brine shrimp lethality assay was used to analyze the cytotoxicity of the fungal extracts. Results: Out of 16 different Taxus trees sampled from different locations of Dhorpatan, 13 distinctive endophytic fungi were isolated and grouped into 9 different genera: Bjerkandera, Trichoderma, Preussia, Botrytis, Arthrinium, Alternaria, Cladosporium, Sporormiella and Daldinia. The ethyl acetate extracts isolated from three endophytic fungi: Alternaria alternata, Cladosporium cladosporioides and Alternaria brassicae showed significant TPC values of 204±6.144, 312.3±2.147 and 152.7±4.958µg GAE/mg of dry extract, respectively, and TFC values of 177.9±2.911, 644.1±4.202 and 96.38±3.851µg RE/mg of dry extract, respectively. Furthermore, these three extracts showed a dose dependent radical scavenging activity with IC 50 concentration of 22.85, 22.15 and 23.001 µg/ml, respectively. The extracts of C. cladosporioides and A. brassicae also showed promising antimicrobial activity against Escherichia coli, Staphylococcus aureus and Bacillus subtilis with a minimum inhibitory concentration of 250μg/ml for all bacteria. Both the samples showed cytotoxic property against shrimp nauplii with LC 50 of 104.2 and 125.9µg/ml, respectively. Conclusions: The crude fungal extracts obtained from endophytes: A. alternata, C. cladosporioides and A. brassicae upon purification and further identification of the bioactive compounds can be a fascinating source for novel pharmaceutical agents.

Evaluation of antimicrobial, antioxidant and cytotoxic properties of bioactive compounds produced from endophytic fungi of Himalayan yew ( Taxus wallichiana) in Nepal

Background: Endophytic fungi are largely underexplored in the discovery of natural bioactive products though being rich sources of novel compounds with promising pharmaceutical potential. In this study, Taxus wallichiana, which has huge medicinal value, was investigated for its endophytic diversity and capability to produce bioactive secondary metabolites by analyzing antioxidant, antimicrobial and cytotoxic properties. Methods: The endophytes were identified by ITS-PCR using genomic DNA samples. The secondary metabolites were extracted by solvent extraction method using ethyl acetate. The antioxidant activity was analyzed by Thin Layer Chromatography, Total Phenol Content (TPC), Total Flavonoid Content (TFC) and DPPH assay, and the antimicrobial activity was analyzed by agar-well diffusion method. Brine shrimp lethality assay was used to analyze the cytotoxicity of the fungal extracts. Results: Out of 16 different Taxus trees sampled from different locations of Dhorpatan, 13 distinctive endophytic fungi were isolated and grouped into 9 different genera: Bjerkandera, Trichoderma, Preussia, Botrytis, Arthrinium, Alternaria, Cladosporium, Sporormiella and Daldinia. The ethyl acetate extracts isolated from three endophytic fungi: Alternaria alternata, Cladosporium cladosporioides and Alternaria brassicae showed significant TPC values of 204±6.144, 312.3±2.147 and 152.7±4.958µg GAE/mg of dry extract, respectively, and TFC values of 177.9±2.911, 644.1±4.202 and 96.38±3.851µg RE/mg of dry extract, respectively. Furthermore, these three extracts showed a dose dependent radical scavenging activity with IC 50 concentration of 22.85, 22.15 and 23.001 µg/ml, respectively. The extracts of C. cladosporioides and A. brassicae also showed promising antimicrobial activity against Escherichia coli, Staphylococcus aureus and Bacillus subtilis with a minimum inhibitory concentration of 250μg/ml for all bacteria. Both the samples showed cytotoxic property against shrimp nauplii with LC 50 of 104.2 and 125.9µg/ml, respectively. Conclusions: The crude fungal extracts obtained from endophytes: A. alternata, C. cladosporioides and A. brassicae upon purification and further identification of the bioactive compounds can be a fascinating source for novel pharmaceutical agents.

Present Status Of Medicinal and Aromatic Plants of Jammu, Kashmir and Ladakh region of Himalayas

The conservation and cultivation of medicinal and aromatic plants (MAP) are getting more importance. MAPs in India are being collected/cultivated in diverse climatic conditions starting from seacoast to high Himalayas in varied soil conditions. Among them temperate, alpine and cold arid regions of country have vital importance for MAPS. The Northern region Himalayas viz. Jammu, Kashmir and Ladakh which represents temperate, alpine and cold arid region zone finds first place in medicinal and aromatic plants conservation/cultivation. It has more than 300 MAP and out of them around 16 very important and prioritized medicinal plants viz., Aconitum heterophyllum, Artemesia absinthium, Picrorhiza kurroa, Swertia chirayita, Saussurea costus, Withania somnifera, Acorus calamus, Atropa acuminata, Berberis aristata, Cathranthus roseus, Dioscorea deltoidea, Taxus wallichiana. Podophyllum hexandrum, Hippophae rhamnoides, Dactylorhiza hatagirea and Arnebia benthamii and aromatic plants viz. Levandula officinalis, Rosmarinus officinalis, Organium vulgare . Thymus serpyllum are exclusive aromatic crops of temperate region with potential to be commercialized. Most of these plants are extracted from wild and have very high demand.

Use of Root Microbiome in Conservation of Himalayan Yew (Taxus wallichiana Zucc.): An Ecofriendly Approach

The root microbiome, endophytes in particular, plays a crucial role in functioning of the host plant. These microorganisms, as a consortium, can be used as a part of the propagation protocol for producing healthy plants. Himalayan yew (Taxus wallichiana Zucc.) is an important medicinal plant species, mainly due to its known anticancer property. This species is listed in IUCN red list of threatened species and hence a priority candidate for conservation. Microscopic examination of T. wallichiana roots clearly indicates heavy colonization by mycorrhizae and other endophytes. The present study illustrates the application of the root-associated microbiome for raising healthy plantlets of T. wallichiana, using stem cuttings for field transfer, as an ecofriendly nursery practice.

Characterization of the complete chloroplast genome of Taxus wallichiana as the medicinal plant from China

Taxus wallichiana is a member of the family Taxaceae, which is a unique and endangered species in China and is widely used for ornamental, material and medicinal purposes. The complete chloroplast genome of T. wallichiana was found to possess a total size of 128,168 bp. The GC content of T. wallichiana chloroplast genome sequence is 37.3%, the overall nucleotide composition of chloroplast genome sequence is: A of 30.7%, T of 32.0%, C of 19.0% and G of 18.3%. The total of 116 genes were successfully annotated, which contained 83 protein-coding genes, 29 transfer RNA genes, and 4 ribosomal RNA genes. The ML phylogenetic analysis result showed that T. wallichiana was closely related to Taxus baccata in the phylogenetic relationship using the neighbour-joining (NJ) method in this study.

Bioprospecting plant growth promoting endophytic bacteria isolated from Himalayan yew (Taxus wallichiana Zucc.)

The present study aims to investigate the endophytic bacteria, isolated from the roots of Taxus wallichiana Zucc. and designated as GBPI_TWL and GBPI_TWr, for their plant growth promoting traits. On the basis of phenotypic and molecular characters, the bacteria are identified as species of Burkholderia and Enterobacter, respectively. Both the bacteria could grow at wide range of temperature (5−40 °C, opt=25 °C) and pH (1.5–11.0, opt = 6–7), and tolerate salt concentration up to 12 %. While both the bacterial endophytes possessed siderophore, HCN, ammonia, and salicyclic acid producing abilities, GBPI_TWL showed IAA and ACC deaminase producing abilities, in addition. The bacteria were found to be potential phosphate solubilizers at wide temperature range (5−35 °C) by utilizing tricalcium, iron, and aluminium phosphate as substrate. Further, the bacterial isolates produced phytase and phosphatase enzymes in both acidic and alkaline conditions. Positive influence of the inoculation with the bioformulations of GBPI_TWL and GBPI_TWr was demonstrated on the test crops namely rice (Oryza sativa) and soybean (Glycine max) with respect to physico-chemical and plant growth parameters in net house experiments. The study will have implications in developing bioformulations, specifically for low temperature environments, in view of environmental sustainability.

Establishment of regenerative callus, cell suspension system, and molecular characterization of Taxus wallichiana Zucc. for the in vitro production of Taxol

Taxus wallichiana, an endangered Taxus species native to Nepal, is a source of Taxol (paclitaxel), an anticancer drug, which if produced via plant cell culture in vitro not only reduces the pressure on natural habitat but also allows continuous production throughout the seasons. Gamborg’s B5 medium was the culture medium to develop callus and suspension culture. Quantification of Taxol was carried out via high performance liquid chromatography (HPLC) using C18 column, water-acetonitrile mobile phase, and 1 ml/minute flowrate at 227 nm wavelength. Genetic variation among population was determined using the POPGEN32, version 1.31. Best callus response was in medium with 1 mg/l 2,4-D for both stem and needle explants. For cell suspension culture, callus from needle explants showed better response compared to stem. Fructose and sucrose proved to be the best carbon sources. Cell count increased as carbon concentration increased. 2,4-D at low concentration (5 mg/l) showed higher cell growth rate. Inoculum volume was directly proportional to cell count. Extra addition of macronutrients had inhibitory effect on cell count, but the effect was reversed for MgSO4. Using HPLC, for bark, the highest Taxol yield was 0.057 mg/g distilled water (DW), while for needle was 0.056 mg/g DW. For suspension cultured HPLC samples, Taxol yield ranged at 0.004%. Size range of amplified Deoxyribonucleic acids was between 200 and 2,000 bp. Thus, this investigation generated a concrete data for Taxus population of Nepal providing efficient protocols for establishment of callus and cell suspension culture with the aim of producing Taxol in in vitro conditions.

CHEMICAL CONSTITUENTS OF ETHYL ACETATE EXTRACT FROM Taxus wallichiana ZUCC. (TAXACEAE) LEAVES COLLECTED IN HA GIANG PROVINCE

Investigation on the chemical constituents of ethyl acetate extract from leaves of Taxus wallichiana Zucc. (Taxaceae), collected in Ha Giang province, has resulted in the isolation of three metabolites for the first time: sciadopitysin (1), β-sitosterol (2), and isoquercitrin (3). Their structures were determined by spectroscopic methods.