Secondary metabolite fingerprinting, anti-pathogenic activity, elite chemotype selection and conservation of Curcuma caesia- an ethnomedicinally underutilized species.

Curcuma caesia Roxb. is an ethnomedicinally important, essential oil (EO) yielding aromatic plant. A total of twelve accessions of this plant rhizome were collected from six different agro-climatic zones of West Bengal, India and evaluated for their antimicrobial activities against eight disease-causing, multi-drug-resistant pathogenic strains of urinary-tract infection and respiratory-tract infection. The EO and extracts demonstrated antibacterial activity, with the highest inhibition zone of 18.00 ± 0.08 and 17.50 ± 0.14 mm against Klebsiella pneumoniae by accession 06, even where all the broad-spectrum antibiotics failed to respond. In this study, we employed high-performance thin-layer chromatography (HPTLC) to quantify curcumin, the primary secondary metabolite of C. caesia, and the highest 0.228 mg/gm of curcumin resulted from accession 06. Hence, on the basis of all aspects, accession 06 was identified as the elite chemotype among all twelve accessions. The chemical profiling of EO from accession 06 was done using gas chromatography-mass spectroscopy (GC-MS). Conceivably, about 13 medicinally significant compounds were detected. As this plant species is seasonal and has difficulties in conventional breeding due to dormancy, it must be conserved through in vitro tissue culture for a steady supply throughout the year in massive amounts for agricultural demand. A maximum number of 19.28 ± 0.37 shoots has been obtained in MS medium fortified with 6-Benzylaminopurine, Kinetin, and Naphthalene acetic acid. The genetic uniformity of the plants has been studied through Start Codon Targeted Polymorphism. Therefore, this study must help meet the need for essential phytoactive compounds through a simple, validated, and reproducible plant tissue culture protocol throughout the year.

Hairy root culture: a potent method for improved secondary metabolite production of Solanaceous plants.

Secondary metabolites synthesized by the Solanaceous plants are of major therapeutic and pharmaceutical importance, many of which are commonly obtained from the roots of these plants. 'Hairy roots', mirroring the same phytochemical pattern of the corresponding root of the parent plant with higher growth rate and productivity, are therefore extensively studied as an effective alternative for the in vitro production of these metabolites. Hairy roots are the transformed roots, generated from the infection site of the wounded plants with Agrobacterium rhizogenes. With their fast growth, being free from pathogen and herbicide contamination, genetic stability, and autotrophic nature for plant hormones, hairy roots are considered as useful bioproduction systems for specialized metabolites. Lately, several elicitation methods have been employed to enhance the accumulation of these compounds in the hairy root cultures for both small and large-scale production. Nevertheless, in the latter case, the cultivation of hairy roots in bioreactors should still be optimized. Hairy roots can also be utilized for metabolic engineering of the regulatory genes in the metabolic pathways leading to enhanced production of metabolites. The present study summarizes the updated and modern biotechnological aspects for enhanced production of secondary metabolites in the hairy root cultures of the plants of Solanaceae and their respective importance.

Phytogenic silver nanoparticles from tissue-cultured Kaempferia angustifolia - an underutilized medicinal herb: a comparative antibacterial study on urinary pathogens.

BACKGROUND: Ethnomedicinally important Kaempferia angustifolia is a rhizomatous aromatic herb belonging to the family Zingiberaceae. The present manuscript deals with the green synthesis of silver nanoparticles through a rapid reduction process mediated by the rhizome extract of tissue culture-raised plants. The present study was conducted to evaluate the antimicrobial activity of the bio-nanoparticles, and the plant extracts themselves against seven multidrug-resistant urinary tract infecting (MDR-UTI) pathogens. RESULT: The ethanolic extracts of the rhizomes of the plant executed a very rapid synthesis of silver bio-nanoparticles, and the generation of the nanoparticles was confirmed through UV-vis spectrophotometry, dynamic light scattering (DLS), and electron dispersion spectroscopic (EDS) analysis. Finally, the precise shapes and dimensions of these nanoparticles were confirmed under the transmission electron microscope (TEM). The shapes of the nanoparticles obtained were diverse in nature and varied from rod, triangular, spherical, to oval shaped, with the size, ranging from 10-60 nm. Silver nanoparticles exhibited a maximum zone of inhibition (ZI) of 16.93 ± 0.04 mm against isolate no. 42332. The ex vitro and in vivo extracts exhibited ZI 14.03 ± 0.04 mm and 11.56 ± 0.04 mm, respectively, against the same strain, which are comparatively lower than the nanoparticles but unignorable. CONCLUSION: Although the pathogens used in the present study are resistant to at least three or more types of pharmacologically important antibiotics, nanoparticles, as well as the plant extracts, exhibited significant inhibition to all the seven MDR-UTI pathogens, which confirms that they are highly antimicrobic. Hence, this underutilized medicinal plant extracts of K. angustifolia and the bio-nanoparticles synthesized from these can be explored in pharmaceutical industries to treat multidrug-resistant human pathogenic bacteria. Furthermore, their broad-spectrum activity leads to the opportunity for the synthesis of future generation drugs.

Silver nanoparticle synthesis and their potency against multidrug-resistant bacteria: a green approach from tissue-cultured Coleus forskohlii.

Drug resistance is a major concern nowadays, and finding alternatives of the well-known antibiotic is necessary. Green nanoparticles are emerging as a tenable alternative to this with a large spectrum of activity. The present manuscript describes an eco-friendly approach for green synthesis of silver nanoparticles from both in vitro and in vivo leaf extract of Coleus forskohlii. Leaf extracts were used in synthesis of nanoparticles which were further analyzed through UV-Vis, dynamic light scattering, energy-dispersive spectroscopy, and transmission electron microscopy. Antimicrobial activity of silver nanoparticles alone, as well as crude extract of the plant itself, was carried out against eight multidrug-resistant respiratory tract infecting pathogenic strains. Satisfactory antimicrobial activities were found with nanoparticles, in vitro and in vivo leaf extracts. However, gradually higher to lower inhibition potential against pathogenic bacterial strains was found in silver nanoparticles, in vitro and in vivo leaf extracts. Seven bioactive compounds were detected in the crude extract through gas chromatography-mass spectroscopy analysis. Results revealed that nanoparticle formation occurred in a wide range of sizes (10-50 nm) and shapes (trigonal, hexagonal, spherical, rod). The diversity in size and shape of the nanoparticles makes them biologically active. Silver nanoparticle exhibits significantly better antimicrobial activities as compared to the plant extract in case of nearly all pathogens with a maximum zone of inhibition of 15.33 ± 0.94 mm where more than 12 well-known antibiotics failed to respond. Because of this broad-spectrum activity of nanoparticles as well as the leaf extracts against life-threatening microbes, it can be used as future generation drugs.

Variation in content of taxol and related taxanes in Eastern Himalayan populations of Taxus wallichiana.

Extraction and analysis of paclitaxel and other taxanes in bark, needle leaves and stem segments of male and female plants of Taxus wallichiana, representing several populations, indicate that significant variation in taxane content exists within the population. Bark accumulated maximum amount of paclitaxel in almost all plants. Populations located at higher altitude tended to accumulate more paclitaxel than lower altitude plants. Seasons in which samples were collected and plant age have also been shown to affect paclitaxel accumulation. No effects of plant sex on paclitaxel content of the plants analyzed were observed. Significant differences in baccatin-III and 10-deacetylbaccatin III content were found to exist in the trees analyzed in this study.