The influence of different hormone concentration and combination on callus induction and regeneration of Rauwolfia serpentina L. Benth

Influence of bio fabricated manganese oxide nanoparticles for effective callogenesis of Moringa oleifera Lam

The use of nanoscale fertilizers to boost crop output has increased in recent years. Nanoparticles (NPs) can stimulate the biosynthesis of bioactive compounds in plants. It is the first report on biosynthesized manganese oxide nanoparticles (MnO-NPs) that mediate in-vitro callus induction of Moringa oleifera. To achieve better biocompatibility the leaf extract of Syzygium cumini was used to synthesize MnO-NPs. Scanning electron microscope SEM revealed spherical shaped morphology of MnO-NPs with an average diameter of 36 ± 0.3 nm. Energy-dispersive X-ray spectroscopy (EDX) depicted the formation of pure MnO-NPs. X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) authenticate the crystalline structure. UV-visible absorption spectroscopy depicted the activity of MnO-NPs under visible light. The biosynthesized MnO-NPs were concentration-dependent and revealed promising results in callus induction of Moringa oleifera. It was found that MnO-NPs enhance callus production of Moringa oleifera and keep the callus infection free by providing an optimum environment for rapid growth and development. Therefore MnO-NPs synthesized through the green process can be utilized in tissue culture studies. This study concludes that MnO is one of the essential plant nutrients that have tailored nutritive properties at a nano scale.

Biotechnological interventions on the genus Rauvolfia: recent trends and imminent prospects

Rauvolfia spp., also known as devil peppers, are a group of evergreen shrubs and trees. Among the ~ 76 various species, Rauvolfia serpentina is the most important one as it finds its use as an important medicinal plant. It is commonly known as the Indian snakeroot plant or Sarpagandha. The plant is rich in multiple secondary metabolites. Some of the well-known secondary metabolites are reserpine, ajmaline, ajmalicine, serpentine, yohimbine, etc. Alkaloids are also found in all parts of the plant but the richest sources are the roots. Since ancient times, roots (mainly due to reserpine) have been utilized in various Ayurvedic and Unani medicinal preparations for the treatment of diseases like hypertension, anxiety, insomnia and schizophrenia. Apart from this, there are many other pharmacological and ethnobotanical uses of this plant. There are a number of published reports regarding tissue culture techniques on Rauvolfia spp. The current review mainly illustrates and discusses the various in vitro biotechnological aspects such as direct regeneration, indirect regeneration via callus formation, somatic embryogenesis, synthetic seed production, hairy root culture, polyploidy induction and secondary metabolite estimation, which provides significant ideas regarding the ongoing research activities and future prospects related to the genetic improvement of this genus.

In vitro production of alkaloids: Factors, approaches, challenges and prospects

The wide diversity of plant secondary metabolites is largely used for the production of various pharmaceutical compounds. In vitro cell tissue or organ culture has been employed as a possible alternative to produce such industrial compounds. Tissue culture techniques provide continuous, reliable, and renewable source of valuable plant pharmaceuticals and might be used for the large-scale culture of the plant cells from which these secondary metabolites can be extracted. Alkaloids are one of the most important secondary metabolites known to play a vital role in various pharmaceutical applications leading to an increased commercial importance in recent years. The tissue culture techniques may be utilized to improve their production of alkaloids via somaclonal variations and genetic transformations. The focus of this review is toward the application of different tissue culture methods/techniques employed for the in vitro production of alkaloids with a systematic approach to improve their production.

Influence of abiotic stress signals on secondary metabolites in plants

Plant secondary metabolites are unique sources for pharmaceuticals, food additives, flavors, and industrially important biochemicals. Accumulation of such metabolites often occurs in plants subjected to stresses including various elicitors or signal molecules. Secondary metabolites play a major role in the adaptation of plants to the environment and in overcoming stress conditions. Environmental factors viz. temperature, humidity, light intensity, the supply of water, minerals, and CO2 influence the growth of a plant and secondary metabolite production. Drought, high salinity, and freezing temperatures are environmental conditions that cause adverse effects on the growth of plants and the productivity of crops. Plant cell culture technologies have been effective tools for both studying and producing plant secondary metabolites under in vitro conditions and for plant improvement. This brief review summarizes the influence of different abiotic factors include salt, drought, light, heavy metals, frost etc. on secondary metabolites in plants. The focus of the present review is the influence of abiotic factors on secondary metabolite production and some of important plant pharmaceuticals. Also, we describe the results of in vitro cultures and production of some important secondary metabolites obtained in our laboratory.