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The quinolinate phosphoribosyl transferase (QPT) is a key enzyme that converts quinolinic acid into nicotinic acid mononucleotide. The QPT gene plays an essential role in the pyridine nucleotide cycle as well as in the biosynthetic pathway of the alkaloid nicotine. However, a clear role for QPT is yet to be characterized to validate the actual function of this gene in planta. In this study, an RNA interference (RNAi) approach was used to reveal the functional role of QPT. Transformation and analysis of the hairy roots (HRs) of the Nicotiana leaf explants was used, followed by plant regeneration and analysis. High-performance liquid chromatography (HPLC) analysis of the HRs and of the regenerated plants both revealed altered alkaloid biosynthetic cycle, with a substantially reduced content of nicotine and anabasine. The transgenic plants exhibited a significantly altered phenotype and growth pattern. Also, silencing of QPT led to a decrease in chlorophyll content, maximum quantum efficiency of PSII, net CO2 assimilation and starch content. Results clearly demonstrated that QPT was not only involved in the biosynthetic pathway of the alkaloids but also affected plant growth and development. Our results provide information to be considered when trying to engineer the secondary metabolite quality and quantity. [ABSTRACT FROM AUTHOR]

Background: Pyrethrins are monoterpenoids and consist of either a chrysanthemic acid or pyrethric acid with a rethrolone moiety. Natural pyrethrins are safe and eco-friendly while possessing strong insecticidal properties. Despite such advantages of commercial value coming with the eco-friendly tag, most enzymes/genes involved in the pyrethrin biosynthesis pathway remain unidentified and uncharacterized. Since the flowers of Tanacetum cinerariifolium are rich in major pyrethrins, next generation transcriptome sequencing was undertaken to compare the flowers and the leaves of the plant de novo to identify differentially expressed transcripts and ascertain which among them might be involved in and responsible for the differential accumulation of pyrethrins in T. cinerariifolium flowers. Results: In this first tissue specific transcriptome analysis of the non-model plant T. cinerariifolium, a total of 23,200,000 and 28,500,110 high quality Illumina next generation sequence reads, with a length of 101 bp, were generated for the flower and leaf tissue respectively. After functional enrichment analysis and GO based annotation using public protein databases such as UniRef, PFAM, SMART, KEGG and NR, 4443 and 8901 unigenes were identified in the flower and leaf tissue respectively. These could be assigned to 13344 KEGG pathways and the pyrethrin biosynthesis contextualized. The 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway was involved in the biosynthesis of acid moiety of pyrethrin and this pathway predominated in the flowers as compared to the leaves. However, enzymes related to oxylipin biosynthesis were found predominantly in the leaf tissue, which suggested that major steps of pyrethrin biosynthesis occurred in the flowers. Conclusions: Transcriptome comparison between the flower and leaf tissue of T. cinerariifolium provided an elaborate list of tissue specific transcripts that was useful in elucidating the differences in the expression of the biosynthetic pathways leading to differential presence of pyrethrin in the flowers. The information generated on genes, pathways and markers related to pyrethrin biosynthesis in this study will be helpful in enhancing the production of these useful compounds for value added breeding programs. Related proteome comparison to overlay our transcriptome comparison can generate more relevant information to better understand flower specific accumulation of secondary metabolites in general and pyrethrin accumulation in particular. [ABSTRACT FROM AUTHOR]

A field experiment was conducted to study the influence of combined use of farm yard manure and inorganic fertilizers on biomass and essential oil yields, chemical and microbial biomass carbon and nitrogen of soil grown with peppermint (Mentha piperita) in a hilly region, Bageshwar, India. Combined application of both farm yard manure and inorganic fertilizers increased the biomass and oil yields of peppermint compared to sole inorganic fertilizers treatments. The treatments receiving both farm yard manure and inorganic fertilizers improved the soil organic carbon and total N from initial value of 3.9 to 7.0 g kg-1soil and 0.27 to 0.58 g kg-1soil, respectively. A significant improvement has been noticed in soil respiration, soil microbial biomass carbon and nitrogen compared to inorganic fertilizer alone. Moreover, different proportions of inorganic fertilizers with farm yard manure had significant variation on available major soil nutrients. A significant correlation coefficient (r= 0.41* to 0.98**) was observed between yields and soil properties. The quality of essential oil was good and acceptable for the market. [ABSTRACT FROM PUBLISHER]

Vermicompost (VC) produced from distillation waste of geranium (Pelargonium graveolens), farmyard manure (FYM) produced from animal excreta mixed with pine needle (Pinussp.), and biofertilzer (Azotobacter) were utilized for this experiment. The plant growth attributes, biomass, and oil yield of geranium were significantly increased with integrated nutrient supply, and maximum increase was found in T8treatments (N100P60K60+ 5t VC). Soil organic carbon (Corg) significantly increased by 4.2% to 81.8% in T4and T8treatments, respectively, over the control. Data obtained on total nitrogen (Nt) and available N, phosphorus (P), and potassium (K) clearly showed that the integrated nutrient supply considerably improved the soil health and sustainability. The soil respiration and microbial biomass C (Cmic) and N (Nmic) were increased by the manures according to the application rate. The Cmicaccounted for 1.8 to 2.7% of the soil Corgcontent and microbial N accounted for 3.9 to 5.8 % of Ntunder different treatment combinations. [ABSTRACT FROM AUTHOR]

To enhance the production of terpenoid indole alkaloids in Rauwolfia serpentina, Catharanthus tryptophan decarboxylase ( Crtdc) gene was over-expressed in transgenic hairy root cultures using Agrobacterium rhizogenes-mediated transformation. Among six transgenic hairy root lines, line RT4 accumulated the highest alkaloid content, with 0.1202 % dry weight (DW) reserpine and 0.0064 % DW ajmalicine, after 10 weeks of culture. Whereas, wild-type roots accumulated 0.0596 ± 0.003 % DW reserpine and 0.0011 ± 0.001 % DW ajmalicine. Transgenic hairy root line RT7 produced the lowest alkaloid content (reserpine: 0.0896 ± 0.002 % DW; ajmalicine: 0.002 ± 0.0 % DW). On the basis of alkaloid content the six hairy root lines were grouped as RT4/RT2 > RT3/RT5 > RT7/RT8. Analysis of gene expression profile indicated that Crtdc was expressed at a higher level in transgenic lines, which could be correlated with enhanced metabolite accumulation in roots. This study confirms that over-expression of Crtdc is a superlative method to improve the biosynthetic potential of Rauwolfia hairy root cultures. Enhanced reserpine and ajmalicine production can serve as an alternative choice to provide resources for relative pharmaceutical industries. [ABSTRACT FROM AUTHOR]

To determine the seasonal influence on essential oil yield and composition of three rose-scented geranium cultivars, namely Bourbon type, CIM-Pawan and Kelkar, an experiment was carried out in western Himalayan region, India. The essential oil yield varied from 0.05% to 0.20%, from 0.10% to 0.25% and from 0.03% to 0.12% in fresh biomass of the cv. Bourbon type, CIM-Pawan and Kelkar, respectively. Gas chromatography/flame ionization detector (GC/FID) and /mass spectrometry (GC/MS) analyses revealed significant variations in the essential oil composition of rose-scented geranium due to cultivar and season of harvesting. The major components in the essential oil of cv. Bourbon type were geraniol (14.1–34.6%), citronellol (15.2–31.3%), linalool (2.9–9.2%), citronellyl formate (4.4–9.2%), isomenthone (4.5–6.6%), 10-epi-γ-eudesmol (4.7–6.7%) and geranyl formate (3.8–6.2%). The dominant constituents of the cv. CIM-Pawan essential oil were geraniol (11.9–31.9%), citronellol (16.1–30.2%), citronellyl formate (5.2–8.9%), linalool (3.7–6.4%), isomenthone (4.0–6.3%), 10-epi-γ-eudesmol (4.4–5.2%) and geranyl formate (4.3–5.0%). However, the chemical composition and odor of cv. Kelkar was quite different from the other two cultivars and the major components found in this oil were citronellol (51.0–63.4%) and isomenthone (9.8–17.8%). [ABSTRACT FROM PUBLISHER]

Agrobacterium rhizogenes-mediated 'hairy root' cultures were established in Atropa acuminata. The chemical profiling of the hairy roots was carried out by a new mass spectrometric technique, direct analysis in real time (DART). The intact hairy roots were directly analyzed by holding them in the gap between the DART ion source and mass spectrometer. Two alkaloids, atropine and scopolamine, were characterized. The structural confirmation of the two alkaloids was made through their accurate molecular formula determinations. This is the first report of establishing hairy roots in A. acuminata as well as application of the DART technique for the chemical profiling of its hairy roots. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The flavor of vanilla is a complex blend of compounds, with vanillin as the most prominent, along with vanillyl alcohol and 4-hydroxybenzoic acid. Natural vanillin extracted from vanilla beans is expensive, so researchers use heterologous synthesis to produce nature-identical vanillin in plant hosts. Consequently, alternative traditional farming and gathering methods are required to bridge the significant disparity between supply and demand. The current research successfully developed a method to induce hairy root formation from leaves. It integrated the Vanillin synthase (VpVAN) gene into transgenic hairy root lines of Beta vulgaris , synthesizing vanillin-related compounds. The presence of the VpVAN gene in transgenic roots was confirmed using PCR analysis. Additionally, RT-qPCR analysis demonstrated the expression of the VpVAN gene in the transgenic root lines. The transgenic hairy root clones H1, H2, and H5 showed enhanced vanillin production, vanillyl alcohol, and 4-hydroxybenzoic acid. Elicitation with methyl jasmonate (MJ) and salicylic acid (SA) further improved the production of these compounds in B. vulgaris hairy roots. The maximum hairy root biomass was observed after 60 days, with the maximum synthesis of vanillin and 4-hydroxybenzoic acid obtained from hairy root clones H5 and HR2, respectively. Vanillyl alcohol HR2 was obtained on the 45th day of cultivation. Elicitation with wound-associated hormone methyl jasmonate and salicylic acid enhanced the yield of vanillin, vanillyl alcohol, and 4-hydroxybenzoic acid, with a 215-fold increase in vanillin, a 13-fold increase in vanillyl alcohol, and a 21 fold increase in 4-hydroxybenzoic acid. The study results indicate that establishing transgenic hairy root cultures with the VpVAN gene is a promising alternative method for enhancing the production of vanilla flavor compounds such as vanillin, vanillyl alcohol, and 4-hydroxybenzoic acid. A cost-effective protocol has been developed to mass-produce phenolic compounds using a hairy root culture of B. vulgaris . This approach addresses the increasing demand for these substances while reducing the cost of natural vanillin production, making it suitable for industrial-scale applications., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Husain, Warsi, Khan, Mahendran, Afroz, Chandran, Kashyap, Khatoon, Parween, Tandon and Rahman.)

Natural products from plants are of major pharmaceutical and therapeutic importance, several of which are often obtained from the underground parts of the concerned plants. Deviation from standard rules in modern medicines, where instead of a single isolated fraction, a group of naturally occurring components exerts the desired therapeutic effect, was noted in case of Picroliv or Kutkin of Picrorhiza kurroa. "Picroliv" mainly a glucoside, is one such compound, normally obtained from 3 - 4 years old roots and rhizomes of an endangered medicinal plant - Picrorhiza kurroa (kutki) and constitute an important component of many Indian herbal preparations, used mainly for the treatment of a variety of liver ailments. It is an iridoid glycoside mixture containing 60% picroside I and kutkoside in the ratio of 1:1.5. Picroliv has shown efficacy comparable to silymarin in rodent models of galactosamine, paracetamol, thioacetamide and CCl(4) induced hepatic damage. Picroliv has also shown cholerectic effect in rats and anti-cholestatic effect in rats, guinea pigs and cats treated with paracetamol and ethinyl estradiol. It has also anti-viral and immune-stimulant activities and is devoid of any significant CNS and CVS, autonomic and other systemic activity. Because of its apparent ability as a strong hepato-protective and immune-modulatory compound, it is in high demand in both national and international markets. The review discusses the potential of Picrorhiza in various hepatic diseases as well as the chemistry and activity of individual compound of crude drug Picroliv.

The hydrodistilled essential oil of aerial parts of Thymus serpyllum L. (Lamiaceae), cultivated in the Kumaon region of western Himalaya was analyzed by GC and GC-MS. Twenty-nine compounds, representing 91.8% of the oil, were identified. The major components were thymol (58.8%), p-cymene (5.7%), thymol methyl ether (4.0%), borneol (3.8%), sabinene (3.4%), gamma-terpinene (3.4%) and carvacrol methyl ether (3.2%).