Celosia argentea (Var.) cristata (Amaranthaceae) is a widely cultivated ornamental plant, which has antibacterial, astringent, haemostatic, hypertensive, ophthalmic, and parasitic significance. This study describes a protocol for in vitro callus induction and plant regeneration from leaf and stem explants of C. argentea using Murashige and Skoog (MS) medium. Callus culture was initiated and established from seedling, leaf, and stem explants. Explants were cultured on MS medium supplemented with auxin alone (0.5 mg/L Naphthaleneacetic acid (NAA), 2, 4-Dicholorophenoxyacetic acid (2, 4-D). Green and red compact callus (98%) were induced using MS medium supplemented with 0.5 mg/L NAA and 1.0 mg/L Benzyladenine (BA). Two different concentrations (1.0 mg/L BA + 0.5 mg/L NAA and 1.0 mg/L BA + 1.0 mg/L NAA) successfully induced plant regeneration with multiple shoots (1.5 and 0.9 shoots per explants, respectively). Successful shoots were transferred to rooting medium supplemented with 1.0 mg/L Indole-3-acetic acid (IAA) (80%) at 35^th day. Acclimatization was done, which resulted in 90% of the plantlets surviving in garden soil. This protocol could be used to micropropagate C. argentea for conservation, commercial natural product production. The high frequency of callus indicated potential of C. argentea for secondary metabolite production (celosin) in pharmaceutical industry.

Gymnema sylvestre(R.Br.) is an important diabetic medicinal plant which yields pharmaceutically active compounds called gymnemic acid (GA). The present study describes callus induction and the subsequent batch culture optimization and GA quantification determined by linearity, precision, accuracy, and recovery. Best callus induction of GA was noticed in MS medium combined with 2,4-D (1.5 mg/L) and KN (0.5 mg/L). Evaluation and isolation of GA from the calluses derived from different plant parts, namely, leaf, stem and petioles have been done in the present case for the first time. Factors such as light, temperature, sucrose, and photoperiod were studied to observe their effect on GA production. Temperature conditions completely inhibited GA production. Out of the different sucrose concentrations tested, the highest yield (35.4 mg/g d.w) was found at 5% sucrose followed by 12 h photoperiod (26.86 mg/g d.w). Maximum GA production (58.28 mg/g d.w) was observed in blue light. The results showed that physical and chemical factors greatly influence the production of GA in callus cultures ofG. sylvestre. The factors optimized forin vitroproduction of GA during the present study can successfully be employed for their large-scale production in bioreactors.

Chitin oligosaccharides (COSs) can be isolated from various natural resources, which have widely been used in biological active supplements (BAS) for the benefit of humankind. Several technological approaches for the preparation of COSs such as enzymatic, chemical, acid-catalysts hydrolysis, microwave radiation, membrane bioreactor methods have been developed and among them, membrane bioreactor, bioconversion and continuous mass production technologies are reported to be excellent. Compounds isolated from natural products have made a drastic impact on the pharmaceutical industry and especially, water-soluble chitin oligosaccharides have shown greater clinical activity, which have been demonstrated in various cell lines of disease significance. The activities of these COSs were being investigated in different patients, animals and even plants as a broad phase clinical trial program. In the present article, we have discussed the COSs preparation by different methods through comprehensive diffraction procedures along with the merits and demerits given in detail. In addition, a summary of recent work describing the synthesis and biological activities of water-soluble COSs has been presented here.

Summary Gymnemic acid (GA), a well known anti-diabetic compound has been detected in methanol extracts of intact leaves and in vitro callus cultures derived from leaf explants of Gymnema sylvestre. Callus biomass was developed in MS medium with optimum plant growth regulators (OPGRs) of 2,4-D (1.5 mg L⁻¹) + KN (0.5 mg L⁻¹) under abiotic stress conditions at 45 days determined by growth curve analysis. GA detection and quantification were carried out using thin-layer chromatography (TLC), highperformance thin-layer chromatography (HPTLC), high-performance liquid chromatography (HPLC), and gravimetric techniques. GA detection peak area and their absorption spectra were evaluated through HPTLC and HPLC with the standard GA. Quantification of GA had showed the linearity, accuracy, robustness and precision by HPLC. GA content was significantly higher in gravimetric method than HPLC. All these methods were found to be simple, accurate, selective and rapid and could be successfully applied for the determination of GA. It could have potential as a pharmaceutical drug for Type 1 diabetes mellitus (IDDM) and obesity.

Climber plants have attracted global attention for their hidden therapeutic potential and are generally rooted on the ground, but leaves often in full sun and blanketing canopies of trees. Climbers rely on some support from other plants and have active and passive climbing mechanisms with great diversity. Tropical forests are the harbors of enormous different fauna and flora species than any other ecosystem on earth and Malaysia is a biodiversity hotspot in Asia with a good amount of tropical forest cover. On the other hand, Iran is an important source of Herbal plants due to the weather and geographical situation. In this review six species of Malaysian and Iranian plants (Hedera helix, Rosa canina, Vitis vinifera, Aristolochia tagala, Gynura procumbens and Antigonon leptopus) are selected and botanical description, geographical distribution, chemical constituent and medicinal properties of each species is discussed. Despite the rich ethno-medicine knowledge behind the traditional uses of climber plants, the current scientific evidence to support these claims remains scant. More research is still needed to validate the medicinal aspects, beginning by increasing the understanding of the biological actions of the climber plants.