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Papers by Bijaya Pant

Journal of Nepal Biotechnology Association, Mar 14, 2024

A successful micropropagation method was developed via the in-vitro seed germination and seedling... more A successful micropropagation method was developed via the in-vitro seed germination and seedling growth of the epiphytic and/or lithophytic orchid Bulbophyllum leopardinum, a species having horticultural and therapeutic significance. To enhance seed germination, several quantities and combinations of naphthalene acetic acid (NAA), 6-benzyl amino purine (BAP), indole acetic acid (IAA), gibberellic acid (GA3), and coconut water (CW) were added to 0.8% (w/v) agar-solidified MS medium. Half-strength MS medium has been experimented with alone and in combination with BAP, Kinetin (Kn), and GA3 to promote shoot development. In-vitro-developed healthy shoots were chosen to establish roots in a half-strength MS (HMS) medium supplemented with various auxins. The best and earliest seed germination with the greenest protocorms (96.3±0.5% in 7 weeks) was achieved on HMS medium fortified with 15% CW (H15C). Further tests for the shoot as well as root development were continued with an H15C medium. H15C with 1 mg/l BAP and 1.5 mg/l Kinetin was most effective for early in vitro development and differentiation into seedlings with the many long shoots (9.3±0.1 shoots and 2.4±0.1 cm per culture) within 12 weeks of sub-culture. The most suitable rooting hormone was 1 mg/l NAA (4.2±0.26 roots per culture). This medium also produced the longest roots (1.9±0.09 cm per culture). By successfully developing a protocol for the mass propagation of B. leopardinum, this research has enhanced both the cultivation and the commercialization potential of this species.

Journal of Nepal Biotechnology Association, Mar 14, 2024

Paris polyphylla Sm. is a vulnerable medicinal plant employed in the treatment of various ailment... more Paris polyphylla Sm. is a vulnerable medicinal plant employed in the treatment of various ailments. This study seeks to establish a protocol for callus induction, proliferation, and differentiation of P. polyphylla. Immature leaf explants were cultured on MS medium with varying concentrations of plant growth regulators (PGRs), including 2,4dichlorophenoxyacetic acid (2,4-D), kinetin (Kn), 6-benzylaminopurine (BAP), Thidiazuron (TDZ), α-Naphthalene acetic acid (NAA), and Gibberellic acid (GA3), along with 10% coconut water. After 12 weeks of primary culture, the optimal callus induction was observed in MS medium supplemented with 0.25 mg/l 2,4-D + 0.5 mg/l Kn. In the secondary culture at 8 weeks, the best callus proliferation, as determined by callus weight or growth index, occurred in MS medium supplemented with 2.0 mg/l BAP alone, 2.0 mg/l Kn alone, 1.0 mg/l TDZ alone, combinations of 2.0 mg/l Kn + 1.0 mg/l BAP + 2.0 mg/l GA3, and combinations of 0.5 mg/l NAA + 2.0 mg/l BAP + 2.0 mg/l GA3, as well as 10% coconut water. Furthermore, callus differentiation into mini rhizomes with root primordia was successfully achieved in MS media containing 2.5 mg/l Kn and 10% coconut water. This study reports, for the first time, the formation and differentiation of callus from leaf explants in P. polyphylla. Large-scale callus generation from leaf explants has the potential to enhance the production of bioactive secondary metabolites for therapeutic purposes and facilitate the development of plantlets through organogenesis.

Journal of Institute of Science and Technology, Dec 20, 2023

Lilium nepalense, a temperate medicinal plant, is used as a diuretic, antipyretic, tonic, flavori... more Lilium nepalense, a temperate medicinal plant, is used as a diuretic, antipyretic, tonic, flavoring agent, and heart pain treatment. This research aimed to evaluate the in vitro antioxidant and antidiabetic activities of the methanol, dichloromethane (DCM), and hexane fractions, and in vivo cytotoxic activities of the crude extracts of the bulb. The antioxidant activity was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, antidiabetic activity by α-glucosidase inhibitory assay, and cytotoxic activity in terms of LC50 (median lethality concentration) by Brine shrimp assay. The DCM fraction showed the strongest antioxidant activity (IC50=134.99±9.75 µg/mL) and highest antidiabetic activity (IC50=182.01±20.50 µg/mL) than other fractions. Similarly, the DCM fraction had the highest total phenolic contents (243.97±33.78 mg of gallic acid equivalent per gram dry weight) and highest flavonoid contents (7.68±0.85 mg of quercetin equivalent per gram dry weight) than other fractions. Moreover, the crude extract of the bulb was not found to be cytotoxic to the Brine shrimp nauplii (LC50=3.83 mg/mL). It is the first report to date describing the antioxidant, antidiabetic, and cytotoxic properties of L. nepalense. This study concludes that the DCM fraction of the bulb could be used as an antioxidant and antidiabetic agent for therapeutic purposes; however, further identification and characterization of bioactive compounds responsible for the antioxidant, antidiabetic, and cytotoxicity is required for further validation.

African Journal of Biotechnology, Feb 3, 2016

Coelogyne stricta (D. Don) Schltr., an orchid of high ornamental and medicinal values, is native ... more Coelogyne stricta (D. Don) Schltr., an orchid of high ornamental and medicinal values, is native to Nepal at 1400 to 2000 m elevations. In vitro seed germination and seedling development was carried out on 0.8% (w/v) agar solidified Murashige and Skoog (MS) medium, supplemented with various combinations of α-naphthalene acetic acid (NAA) and 6-benzylaminopurine (BAP). MS medium supplemented with 1 mg/L BAP and 1 mg/L NAA was found to be the best condition for the development. The germination started after 7 weeks of culture and complete seedlings were obtained after 23 weeks of culture on the medium supplemented with 1 mg/L BAP and 1 mg/L NAA suggesting the usefulness of both hormones in root induction. In the hormone, free MS medium germination started after 5 weeks, but root initials were not developed even after 32 weeks of culture.

Advances in Forestry Science, Dec 19, 2015

Coelogyne flaccida Lindl., an epiphytic orchid native to Nepal, has high ornamental and medicinal... more Coelogyne flaccida Lindl., an epiphytic orchid native to Nepal, has high ornamental and medicinal values and is found at elevations ranging from 900 to 1100 m. In this work in vitro seed germination and seedling development of this orchid was carried out on 0.8% (w/v) agar solidified Murashige and Skoog (MS) medium supplemented with different combinations of α-Naphthalene acetic acid (NAA) and 6-Benzylaminopurine (BAP). MS medium supplemented with 0.5 mg/L BAP and 0.5 mg/L NAA was found to be the ideal condition for the complete development of the seedlings. The germination started after six weeks of culture and developed seedlings were obtained after 22 weeks of culture on the medium supplemented with 0.5 mg/L BAP and 0.5 mg/L NAA. In the medium without hormone application, germination started after five weeks, but roots were not developed even after 32 weeks of culture, suggesting the usefulness of NAA in root induction. The present study has provided useful information that both phytohormones, BAP and NAA are necessary for the fast growth and development of the in vitro grown seedlings.

Natural Medicines, Sep 20, 1995

Scientia Horticulturae, Apr 1, 2021

Abstract Rhynchostylis retusa (L.) is an epiphytic orchid having both medicinal and ornamental va... more Abstract Rhynchostylis retusa (L.) is an epiphytic orchid having both medicinal and ornamental value. The present study aimed to develop a protocol for mass propagation of R. retusa and evaluate the genetic stability of in vitro regenerants. The immature seeds obtained from capsule of mother plants (wild type) were cultured on different strength of MS medium viz. full (FMS), half (HMS), quarter (QMS) supplemented with BAP (0.5 mg/L), NAA (0.5 mg/L), and 5% or 10 % coconut water (CW). The earliest germination and protocorm development were observed on HMS and QMS media. Mature protocorms produced higher number of shoots (12.8) and longest shoots (5.3 cm) on FMS supplemented with 10 % CW. The maximum number of roots (7.3) and root length (5.0 cm) were observed on FMS when supplemented with fungal elicitor CVS4 (extracted from the stem of Vanda cristata). Ten RAPD primers were used to analyze genetic stability among six samples (five in vitro and one mother plant) produced a total of 23 fragments ranging from 275bp to 1100bp. The polymorphic information content (PIC) values ranged from 0.28 to 0.50. The amplified bands of all the samples of in vitro plants were similar to bands of mother plant. The result demonstrated the genetic stability of the micropropagated plants of R. retusa. Research reported here is indicating the applicability of tissue culture for true-to-type plant production and conservation of R. retusa.

African Journal of Plant Science, Dec 31, 2019

Dendrobium primulinum Lindl. (D. Primulinum L.) is one of the important epiphytic orchid species ... more Dendrobium primulinum Lindl. (D. Primulinum L.) is one of the important epiphytic orchid species for horticultural and commercial use. It is listed as a rare and critically endangered species of orchid. The present study is intended to conserve the orchid species through the micropropagation technique. The in vitro seed germination and seedling growth was carried out by taking a mature pod of D. Primulinum L. in Murashige and Skoog (MS) media, and the MS media supplemented with a varied concentration (0.5, 1.0, 1.5 and 2 mg/L) of 6-benzylaminopurine (BAP), and a fixed concentration (0.5 mg/L) of αnaphthalene acetic acid (NAA). Sequential phases of seed germination, protocorm formation, and seedling development in the presence of growth regulators were determined in the study. The significance of hormonal effects was determined by using One-Way Analysis of Variance (ANOVA, p≤0.05). The seed germination started after two weeks of culture in the media supplemented with BAP. The maximum seedling growth was obtained in the media supplemented with 1.5 mg/L of BAP. Although the hormone-free basal medium revealed an ideal condition for seed germination and spherules formation, the presence of an appropriate concentration of growth regulators such as 0.5 mg/L NAA or a combined 0.5 mg/L BAP + 0.5 mg/L NAA expressed a synergistic effect to enhance the protocorm formation and seedling development.

Plants, Dec 28, 2018

The present study aims to identify the diverse endophytic fungi residing in the roots of Dendrobi... more The present study aims to identify the diverse endophytic fungi residing in the roots of Dendrobium moniliforme and their role in plant growth and development. Nine endophytic fungi were isolated from the root sections and characterized by molecular technique. Quantification of the indole acetic acid (IAA) compound by these endophytes was done. Further, Chemical profiling of R11 and R13 fungi was done by Gas Chromatography-Mass Spectroscopy (GC-MS). Asymbiotic seed derived protocorms of Rhynchostylis retusa was used for the plant growth assay to investigate the growth promoting activities of the fungal elicitor prepared from the isolated fungi from D. moniliforme. Among the isolated fungi, the relative dominant fungus was Fusarium sp. The R13 and R6 fungi were identified only at the genus level which concludes the fungi are of new species or strain. The indole acetic acid production was relatively higher in R10. Bioactive compound diversity was observed in the organic extract of R11 and R6. The presence of phenolic compound and essential oil suggest their contribution for the antimicrobial and antioxidant properties to their host plant, D. moniliforme. The plant growth assay result concluded, the fungal elicitor prepared from R10, Colletotrichum alatae was the best among all other for the plant growth activities.

Frontiers in conservation science, Jan 18, 2023

Introduction: Dendrobium species have been widely used for many health disorders since ancient ti... more Introduction: Dendrobium species have been widely used for many health disorders since ancient times. However, due to unrelenting collection to meet the increasing demand for their use in medication and other health products, the natural habitats of medicinal Dendrobium transparens have been devastated and are on the verge of extinction. Methods: An efficient in-vitro propagation protocol for Dendrobium transparens using seed derived protocorms was established and genetic homogeneity of the in-vitro regenerants and the wild plant was studied. Results: The maximum seed germination was observed in Full strength Murashige and Skoog medium (FMS). Induction of protocorms were achieved on basal as well as half-strength MS medium. The highest number of shoot (11.9 shoots/explant) was achieved in half MS medium fortified with 100 mL/L coconut water in addition with Benzyl amino purine (BAP) 1 mg/L and Kinetin 2 mg/L. Further, elongated shoots were transferred to full and half strength MS root initiating medium supplemented with different concentration of auxins. However, a maximum of (8.3 ± 0.6, 4.9 ± 0.1 cm) roots were achieved in full MS medium fortified with 100 mL/L coconut water and Napthalene acetic acid (NAA) 1.5 mg/L. Ten rapid Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeats (ISSR) primers were used to analyze genetic stability among in-vitro and mother plant. RAPD primers produced a total of 23 fragments while ISSR primers produced a total of 16 fragments. Conclusion: The amplified bands of all the samples of in-vitro plants were similar to bands of mother plant. The present research reported here is indicating the applicability of tissue culture for true-to-type plant production and conservation of D. transperens.

Process Biochemistry, 2023

To investigate the antioxidant, antibacterial and cytotoxic activity of whole Leucas aspera (Labi... more To investigate the antioxidant, antibacterial and cytotoxic activity of whole Leucas aspera (Labiatae) (L. aspera) alcoholic extract. Methods: Whole L. aspera powder was extracted by absolute ethanol (99.50%). The ethanolic extract was subjected to antioxidant, antibacterial and brine shrimp lethality assay. Results: The extract showed potent radical scavenging effect (antioxidant) with IC 50 value of (99.58依1.22) µg/mL which was significant (P<0.01) in comparison to ascorbic acid with IC 50 value of (1.25依0.95) µg/mL. In case of antibacterial screening, the extract showed notable antibacterial effect against the tested microbial strains. Significant (P<0.05) zone of inhibitions against Gram positive Bacillus subtilis [(12.00依1.32) mm] and Bacillus megaterium [(13.00依1.50) mm], Staphylococcus aureus [(8.00依0.50) mm] and Gram negative Salmonella typhi [(6.00依0.50) mm], Salmonella paratyphi [(8.00依1.00) mm], Shigella dysenteriae [(9.00依1.32) mm] and Vibrio cholerae [(9.00依0.66) mm] was observed. In brine shrimp lethality bioassay, the extract showed the LC 50 value as (181.68依2.15) µg/mL which was statistically significant (P<0.01) compared to positive control vincristine sulfate [LC 50 =(0.76依0.04) µg/mL]. Conclusions: The results demonstrate that the ethanolic extract of L. aspera could be used as antibacterial, pesticidal and various pharmacologic actives.

Plant Biotechnology Reports

Plant Tissue Culture and Biotechnology

In vitro propagation is one of the most dependable methods to develop true-to-type plants for the... more In vitro propagation is one of the most dependable methods to develop true-to-type plants for the commercial and conservation aspects. This study aims to produce the genetically identical plantlets of Dendrobium crepidatum Lindley and Paxton using in vitrodeveloped shoot explants. Coconut water (5 - 10%) supplemented Murashige and Skoog (MS) medium responded towards effective shoot formation with BAP (1.0 - 2.0 mg/l) and NAA (0.1 - 0.5 mg/l). NAA (0.5 - 1.0 mg/l) alone or in combination with BAP was found to be effective for root initiation in MS medium. Four RAPD (Random Amplified Polymorphic DNA) primers viz., G04, G10, G17 and G18 showed 100% genetic homogeneity in plants obtained from in vitro-developed shoot explant. However, G10, G17 and G18 RAPD primers showed 60, 25 and 100% genetic polymorphisms respectively in plants obtained from callus. Plants obtained from callus were genetically polymorphic where somaclonal variation might occur. This study reported the successful gene...

Heliyon, 2022

Paris polyphylla Sm. is an important medicinal plant used to treat a variety of diseases through ... more Paris polyphylla Sm. is an important medicinal plant used to treat a variety of diseases through traditional medicine systems such as Ayurveda, Tibetan traditional medicines, Chinese traditional medicines, and others around the world. The IUCN red list has designated it as "vulnerable" due to a decline in wild population by over-exploitation, habitat degradation, illegal collection for trade and traditional use. This review paper aims to summarize the bioactive secondary metabolites in Paris polyphylla. Paris saponins or steroidal saponins are the main bioactive chemical constituents from this plant that account for more than 80% of the total compounds. For instance, polyphyllin D, diosgenin, paris saponins I, II, VI, VII, and H are steroidal saponins having anticancer activity comparable to synthetic anticancer medicines. Antioxidant, anticancer, anti-leishmaniasis, antibacterial, antifungal, anthelmintic, antityrosinase, and antiviral effects of extracts and pure compounds were also demonstrated in vivo and in vitro. In conclusion, this review summarizes the bioactive components from the P. polyphylla which will be useful to researchers and scientists, and for the development of potential drugs.

Reference Series in Phytochemistry, 2022

Acta Horticulturae, 2019

In the unique, highly diverse ecosystem of Nepal, Orchidaceae is the largest family of flowering ... more In the unique, highly diverse ecosystem of Nepal, Orchidaceae is the largest family of flowering plants. This family comprises an estimated 454 species, of which 90 are reported to have beneficial medicinal values and 18 are endemic. Orchids are essential in the maintenance of Nepal's biodiversity, due to their epiphytic association with host species, mycorrhizal associations, and pollinators. Medicinal orchids are also important for their commercial value, and many species contain important chemical compounds, including alkaloids, bibenzyl derivatives, flavonoids, phenanthrenes, and terpenoids. Climate change, deforestation, over-exploitation, and illegal trade all pose serious threats to the orchid flora of Nepal, making their conservation a serious concern. Their germplasm is used in Nepal, to conserve both the threatened and commercially important medicinal orchids, ex situ. Various techniques of in vitro culture are used to propagate more than 30 species of medicinal orchids for large scale production. Community awareness and orchid species restoration programs have been conducted with the local people in central Nepal. Further, local people are encouraged to cultivate artificially propagated species as a source of long-term economic benefit.

Journal of Nepal Biotechnology Association, Mar 14, 2024

A successful micropropagation method was developed via the in-vitro seed germination and seedling... more A successful micropropagation method was developed via the in-vitro seed germination and seedling growth of the epiphytic and/or lithophytic orchid Bulbophyllum leopardinum, a species having horticultural and therapeutic significance. To enhance seed germination, several quantities and combinations of naphthalene acetic acid (NAA), 6-benzyl amino purine (BAP), indole acetic acid (IAA), gibberellic acid (GA3), and coconut water (CW) were added to 0.8% (w/v) agar-solidified MS medium. Half-strength MS medium has been experimented with alone and in combination with BAP, Kinetin (Kn), and GA3 to promote shoot development. In-vitro-developed healthy shoots were chosen to establish roots in a half-strength MS (HMS) medium supplemented with various auxins. The best and earliest seed germination with the greenest protocorms (96.3±0.5% in 7 weeks) was achieved on HMS medium fortified with 15% CW (H15C). Further tests for the shoot as well as root development were continued with an H15C medium. H15C with 1 mg/l BAP and 1.5 mg/l Kinetin was most effective for early in vitro development and differentiation into seedlings with the many long shoots (9.3±0.1 shoots and 2.4±0.1 cm per culture) within 12 weeks of sub-culture. The most suitable rooting hormone was 1 mg/l NAA (4.2±0.26 roots per culture). This medium also produced the longest roots (1.9±0.09 cm per culture). By successfully developing a protocol for the mass propagation of B. leopardinum, this research has enhanced both the cultivation and the commercialization potential of this species.

Journal of Nepal Biotechnology Association, Mar 14, 2024

Paris polyphylla Sm. is a vulnerable medicinal plant employed in the treatment of various ailment... more Paris polyphylla Sm. is a vulnerable medicinal plant employed in the treatment of various ailments. This study seeks to establish a protocol for callus induction, proliferation, and differentiation of P. polyphylla. Immature leaf explants were cultured on MS medium with varying concentrations of plant growth regulators (PGRs), including 2,4dichlorophenoxyacetic acid (2,4-D), kinetin (Kn), 6-benzylaminopurine (BAP), Thidiazuron (TDZ), α-Naphthalene acetic acid (NAA), and Gibberellic acid (GA3), along with 10% coconut water. After 12 weeks of primary culture, the optimal callus induction was observed in MS medium supplemented with 0.25 mg/l 2,4-D + 0.5 mg/l Kn. In the secondary culture at 8 weeks, the best callus proliferation, as determined by callus weight or growth index, occurred in MS medium supplemented with 2.0 mg/l BAP alone, 2.0 mg/l Kn alone, 1.0 mg/l TDZ alone, combinations of 2.0 mg/l Kn + 1.0 mg/l BAP + 2.0 mg/l GA3, and combinations of 0.5 mg/l NAA + 2.0 mg/l BAP + 2.0 mg/l GA3, as well as 10% coconut water. Furthermore, callus differentiation into mini rhizomes with root primordia was successfully achieved in MS media containing 2.5 mg/l Kn and 10% coconut water. This study reports, for the first time, the formation and differentiation of callus from leaf explants in P. polyphylla. Large-scale callus generation from leaf explants has the potential to enhance the production of bioactive secondary metabolites for therapeutic purposes and facilitate the development of plantlets through organogenesis.

Journal of Institute of Science and Technology, Dec 20, 2023

Lilium nepalense, a temperate medicinal plant, is used as a diuretic, antipyretic, tonic, flavori... more Lilium nepalense, a temperate medicinal plant, is used as a diuretic, antipyretic, tonic, flavoring agent, and heart pain treatment. This research aimed to evaluate the in vitro antioxidant and antidiabetic activities of the methanol, dichloromethane (DCM), and hexane fractions, and in vivo cytotoxic activities of the crude extracts of the bulb. The antioxidant activity was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, antidiabetic activity by α-glucosidase inhibitory assay, and cytotoxic activity in terms of LC50 (median lethality concentration) by Brine shrimp assay. The DCM fraction showed the strongest antioxidant activity (IC50=134.99±9.75 µg/mL) and highest antidiabetic activity (IC50=182.01±20.50 µg/mL) than other fractions. Similarly, the DCM fraction had the highest total phenolic contents (243.97±33.78 mg of gallic acid equivalent per gram dry weight) and highest flavonoid contents (7.68±0.85 mg of quercetin equivalent per gram dry weight) than other fractions. Moreover, the crude extract of the bulb was not found to be cytotoxic to the Brine shrimp nauplii (LC50=3.83 mg/mL). It is the first report to date describing the antioxidant, antidiabetic, and cytotoxic properties of L. nepalense. This study concludes that the DCM fraction of the bulb could be used as an antioxidant and antidiabetic agent for therapeutic purposes; however, further identification and characterization of bioactive compounds responsible for the antioxidant, antidiabetic, and cytotoxicity is required for further validation.

African Journal of Biotechnology, Feb 3, 2016

Coelogyne stricta (D. Don) Schltr., an orchid of high ornamental and medicinal values, is native ... more Coelogyne stricta (D. Don) Schltr., an orchid of high ornamental and medicinal values, is native to Nepal at 1400 to 2000 m elevations. In vitro seed germination and seedling development was carried out on 0.8% (w/v) agar solidified Murashige and Skoog (MS) medium, supplemented with various combinations of α-naphthalene acetic acid (NAA) and 6-benzylaminopurine (BAP). MS medium supplemented with 1 mg/L BAP and 1 mg/L NAA was found to be the best condition for the development. The germination started after 7 weeks of culture and complete seedlings were obtained after 23 weeks of culture on the medium supplemented with 1 mg/L BAP and 1 mg/L NAA suggesting the usefulness of both hormones in root induction. In the hormone, free MS medium germination started after 5 weeks, but root initials were not developed even after 32 weeks of culture.

Advances in Forestry Science, Dec 19, 2015

Coelogyne flaccida Lindl., an epiphytic orchid native to Nepal, has high ornamental and medicinal... more Coelogyne flaccida Lindl., an epiphytic orchid native to Nepal, has high ornamental and medicinal values and is found at elevations ranging from 900 to 1100 m. In this work in vitro seed germination and seedling development of this orchid was carried out on 0.8% (w/v) agar solidified Murashige and Skoog (MS) medium supplemented with different combinations of α-Naphthalene acetic acid (NAA) and 6-Benzylaminopurine (BAP). MS medium supplemented with 0.5 mg/L BAP and 0.5 mg/L NAA was found to be the ideal condition for the complete development of the seedlings. The germination started after six weeks of culture and developed seedlings were obtained after 22 weeks of culture on the medium supplemented with 0.5 mg/L BAP and 0.5 mg/L NAA. In the medium without hormone application, germination started after five weeks, but roots were not developed even after 32 weeks of culture, suggesting the usefulness of NAA in root induction. The present study has provided useful information that both phytohormones, BAP and NAA are necessary for the fast growth and development of the in vitro grown seedlings.

Natural Medicines, Sep 20, 1995

Scientia Horticulturae, Apr 1, 2021

Abstract Rhynchostylis retusa (L.) is an epiphytic orchid having both medicinal and ornamental va... more Abstract Rhynchostylis retusa (L.) is an epiphytic orchid having both medicinal and ornamental value. The present study aimed to develop a protocol for mass propagation of R. retusa and evaluate the genetic stability of in vitro regenerants. The immature seeds obtained from capsule of mother plants (wild type) were cultured on different strength of MS medium viz. full (FMS), half (HMS), quarter (QMS) supplemented with BAP (0.5 mg/L), NAA (0.5 mg/L), and 5% or 10 % coconut water (CW). The earliest germination and protocorm development were observed on HMS and QMS media. Mature protocorms produced higher number of shoots (12.8) and longest shoots (5.3 cm) on FMS supplemented with 10 % CW. The maximum number of roots (7.3) and root length (5.0 cm) were observed on FMS when supplemented with fungal elicitor CVS4 (extracted from the stem of Vanda cristata). Ten RAPD primers were used to analyze genetic stability among six samples (five in vitro and one mother plant) produced a total of 23 fragments ranging from 275bp to 1100bp. The polymorphic information content (PIC) values ranged from 0.28 to 0.50. The amplified bands of all the samples of in vitro plants were similar to bands of mother plant. The result demonstrated the genetic stability of the micropropagated plants of R. retusa. Research reported here is indicating the applicability of tissue culture for true-to-type plant production and conservation of R. retusa.

African Journal of Plant Science, Dec 31, 2019

Dendrobium primulinum Lindl. (D. Primulinum L.) is one of the important epiphytic orchid species ... more Dendrobium primulinum Lindl. (D. Primulinum L.) is one of the important epiphytic orchid species for horticultural and commercial use. It is listed as a rare and critically endangered species of orchid. The present study is intended to conserve the orchid species through the micropropagation technique. The in vitro seed germination and seedling growth was carried out by taking a mature pod of D. Primulinum L. in Murashige and Skoog (MS) media, and the MS media supplemented with a varied concentration (0.5, 1.0, 1.5 and 2 mg/L) of 6-benzylaminopurine (BAP), and a fixed concentration (0.5 mg/L) of αnaphthalene acetic acid (NAA). Sequential phases of seed germination, protocorm formation, and seedling development in the presence of growth regulators were determined in the study. The significance of hormonal effects was determined by using One-Way Analysis of Variance (ANOVA, p≤0.05). The seed germination started after two weeks of culture in the media supplemented with BAP. The maximum seedling growth was obtained in the media supplemented with 1.5 mg/L of BAP. Although the hormone-free basal medium revealed an ideal condition for seed germination and spherules formation, the presence of an appropriate concentration of growth regulators such as 0.5 mg/L NAA or a combined 0.5 mg/L BAP + 0.5 mg/L NAA expressed a synergistic effect to enhance the protocorm formation and seedling development.

Plants, Dec 28, 2018

The present study aims to identify the diverse endophytic fungi residing in the roots of Dendrobi... more The present study aims to identify the diverse endophytic fungi residing in the roots of Dendrobium moniliforme and their role in plant growth and development. Nine endophytic fungi were isolated from the root sections and characterized by molecular technique. Quantification of the indole acetic acid (IAA) compound by these endophytes was done. Further, Chemical profiling of R11 and R13 fungi was done by Gas Chromatography-Mass Spectroscopy (GC-MS). Asymbiotic seed derived protocorms of Rhynchostylis retusa was used for the plant growth assay to investigate the growth promoting activities of the fungal elicitor prepared from the isolated fungi from D. moniliforme. Among the isolated fungi, the relative dominant fungus was Fusarium sp. The R13 and R6 fungi were identified only at the genus level which concludes the fungi are of new species or strain. The indole acetic acid production was relatively higher in R10. Bioactive compound diversity was observed in the organic extract of R11 and R6. The presence of phenolic compound and essential oil suggest their contribution for the antimicrobial and antioxidant properties to their host plant, D. moniliforme. The plant growth assay result concluded, the fungal elicitor prepared from R10, Colletotrichum alatae was the best among all other for the plant growth activities.

Frontiers in conservation science, Jan 18, 2023

Introduction: Dendrobium species have been widely used for many health disorders since ancient ti... more Introduction: Dendrobium species have been widely used for many health disorders since ancient times. However, due to unrelenting collection to meet the increasing demand for their use in medication and other health products, the natural habitats of medicinal Dendrobium transparens have been devastated and are on the verge of extinction. Methods: An efficient in-vitro propagation protocol for Dendrobium transparens using seed derived protocorms was established and genetic homogeneity of the in-vitro regenerants and the wild plant was studied. Results: The maximum seed germination was observed in Full strength Murashige and Skoog medium (FMS). Induction of protocorms were achieved on basal as well as half-strength MS medium. The highest number of shoot (11.9 shoots/explant) was achieved in half MS medium fortified with 100 mL/L coconut water in addition with Benzyl amino purine (BAP) 1 mg/L and Kinetin 2 mg/L. Further, elongated shoots were transferred to full and half strength MS root initiating medium supplemented with different concentration of auxins. However, a maximum of (8.3 ± 0.6, 4.9 ± 0.1 cm) roots were achieved in full MS medium fortified with 100 mL/L coconut water and Napthalene acetic acid (NAA) 1.5 mg/L. Ten rapid Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeats (ISSR) primers were used to analyze genetic stability among in-vitro and mother plant. RAPD primers produced a total of 23 fragments while ISSR primers produced a total of 16 fragments. Conclusion: The amplified bands of all the samples of in-vitro plants were similar to bands of mother plant. The present research reported here is indicating the applicability of tissue culture for true-to-type plant production and conservation of D. transperens.

Process Biochemistry, 2023

To investigate the antioxidant, antibacterial and cytotoxic activity of whole Leucas aspera (Labi... more To investigate the antioxidant, antibacterial and cytotoxic activity of whole Leucas aspera (Labiatae) (L. aspera) alcoholic extract. Methods: Whole L. aspera powder was extracted by absolute ethanol (99.50%). The ethanolic extract was subjected to antioxidant, antibacterial and brine shrimp lethality assay. Results: The extract showed potent radical scavenging effect (antioxidant) with IC 50 value of (99.58依1.22) µg/mL which was significant (P<0.01) in comparison to ascorbic acid with IC 50 value of (1.25依0.95) µg/mL. In case of antibacterial screening, the extract showed notable antibacterial effect against the tested microbial strains. Significant (P<0.05) zone of inhibitions against Gram positive Bacillus subtilis [(12.00依1.32) mm] and Bacillus megaterium [(13.00依1.50) mm], Staphylococcus aureus [(8.00依0.50) mm] and Gram negative Salmonella typhi [(6.00依0.50) mm], Salmonella paratyphi [(8.00依1.00) mm], Shigella dysenteriae [(9.00依1.32) mm] and Vibrio cholerae [(9.00依0.66) mm] was observed. In brine shrimp lethality bioassay, the extract showed the LC 50 value as (181.68依2.15) µg/mL which was statistically significant (P<0.01) compared to positive control vincristine sulfate [LC 50 =(0.76依0.04) µg/mL]. Conclusions: The results demonstrate that the ethanolic extract of L. aspera could be used as antibacterial, pesticidal and various pharmacologic actives.

Plant Biotechnology Reports

Plant Tissue Culture and Biotechnology

In vitro propagation is one of the most dependable methods to develop true-to-type plants for the... more In vitro propagation is one of the most dependable methods to develop true-to-type plants for the commercial and conservation aspects. This study aims to produce the genetically identical plantlets of Dendrobium crepidatum Lindley and Paxton using in vitrodeveloped shoot explants. Coconut water (5 - 10%) supplemented Murashige and Skoog (MS) medium responded towards effective shoot formation with BAP (1.0 - 2.0 mg/l) and NAA (0.1 - 0.5 mg/l). NAA (0.5 - 1.0 mg/l) alone or in combination with BAP was found to be effective for root initiation in MS medium. Four RAPD (Random Amplified Polymorphic DNA) primers viz., G04, G10, G17 and G18 showed 100% genetic homogeneity in plants obtained from in vitro-developed shoot explant. However, G10, G17 and G18 RAPD primers showed 60, 25 and 100% genetic polymorphisms respectively in plants obtained from callus. Plants obtained from callus were genetically polymorphic where somaclonal variation might occur. This study reported the successful gene...

Heliyon, 2022

Paris polyphylla Sm. is an important medicinal plant used to treat a variety of diseases through ... more Paris polyphylla Sm. is an important medicinal plant used to treat a variety of diseases through traditional medicine systems such as Ayurveda, Tibetan traditional medicines, Chinese traditional medicines, and others around the world. The IUCN red list has designated it as "vulnerable" due to a decline in wild population by over-exploitation, habitat degradation, illegal collection for trade and traditional use. This review paper aims to summarize the bioactive secondary metabolites in Paris polyphylla. Paris saponins or steroidal saponins are the main bioactive chemical constituents from this plant that account for more than 80% of the total compounds. For instance, polyphyllin D, diosgenin, paris saponins I, II, VI, VII, and H are steroidal saponins having anticancer activity comparable to synthetic anticancer medicines. Antioxidant, anticancer, anti-leishmaniasis, antibacterial, antifungal, anthelmintic, antityrosinase, and antiviral effects of extracts and pure compounds were also demonstrated in vivo and in vitro. In conclusion, this review summarizes the bioactive components from the P. polyphylla which will be useful to researchers and scientists, and for the development of potential drugs.

Reference Series in Phytochemistry, 2022

Acta Horticulturae, 2019

In the unique, highly diverse ecosystem of Nepal, Orchidaceae is the largest family of flowering ... more In the unique, highly diverse ecosystem of Nepal, Orchidaceae is the largest family of flowering plants. This family comprises an estimated 454 species, of which 90 are reported to have beneficial medicinal values and 18 are endemic. Orchids are essential in the maintenance of Nepal's biodiversity, due to their epiphytic association with host species, mycorrhizal associations, and pollinators. Medicinal orchids are also important for their commercial value, and many species contain important chemical compounds, including alkaloids, bibenzyl derivatives, flavonoids, phenanthrenes, and terpenoids. Climate change, deforestation, over-exploitation, and illegal trade all pose serious threats to the orchid flora of Nepal, making their conservation a serious concern. Their germplasm is used in Nepal, to conserve both the threatened and commercially important medicinal orchids, ex situ. Various techniques of in vitro culture are used to propagate more than 30 species of medicinal orchids for large scale production. Community awareness and orchid species restoration programs have been conducted with the local people in central Nepal. Further, local people are encouraged to cultivate artificially propagated species as a source of long-term economic benefit.