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Nitric oxide (NO) is known to antagonize ethylene by various mechanisms, one of such mechanisms is reducing ethylene levels by competitive action on S-adenosyl-L-methionine (SAM)&mdash, a common precursor for both ethylene and polyamines (PAs) biosynthesis. In order to investigate whether this mechanism of SAM pool diversion by NO occur towards PAs biosynthesis in banana, we studied the effect of NO on alterations in the levels of PAs, which in turn modulate ethylene levels during ripening. In response to NO donor sodium nitroprusside (SNP) treatment, all three major PAs viz. putrescine, spermidine and spermine were induced in control as well as ethylene pre-treated banana fruits. However, the gene expression studies in two popular banana varieties of diverse genomes, Nanjanagudu rasabale (NR, AAB genome) and Cavendish (CAV, AAA genome) revealed the downregulation of SAM decarboxylase, an intermediate gene involved in ethylene and PA pathway after the fifth day of NO donor SNP treatment, suggesting that ethylene and PA pathways do not compete for SAM. Interestingly, arginine decarboxylase belonging to arginine-mediated route of PA biosynthesis was upregulated several folds in response to the SNP treatment. These observations revealed that NO induces PAs via l-arginine-mediated route and not via diversion of SAM pool.

Pyrethrins are effective food-grade bio-pesticides obtained from the flowers of Chrysanthemum cinerariaefolium and this crop cannot be cultivated widely in India due to its specific agro-climatic requirement. Hence pyrethrins are mostly imported from Kenya. Therefore, the present study aims to develop a process for augmentation of pyrethrin contents in C. cinerariaefolium callus and establish the correlation between early knockdown effects through docking on grain storage insect. In vitro seedlings were used as explants to induce callus on MS medium with different concentrations of auxins and cytokinins. Pyrethrin extracted from the callus was estimated by RP-HPLC. In callus, total pyrethrin was found to be 17.5 µg/g, which is higher than that found in natural flowers of certain Pyrethrum cultivars. The concentrations of cinerin II, pyrethrin II and jasmoline II were quite high in callus grown on solid medium. Bio-efficacy of pyrethrum extracts of flower and callus on insect Tribolium sp., showed higher repellency and early knock-down effect when compared with pure compound pestanal. Further, the rapid knockdown effect of all pyrethrins components was established by molecular docking studies targeting NavMS Sodium Channel Pore receptor docking followed by multiple ligands simultaneous docking, performed to investigate the concurrent binding of different combinations of pyrethrin. Among the six pyrethrin components, the pyrethrin I and II were found to be a more efficient, binding more firmly to the target, exhibiting higher possibilities of insecticidal effect by an early knockdown mechanism.

Pyrethrins are effective food-grade bio-pesticides obtained from the flowers of Chrysanthemum cinerariaefolium and this crop cannot be cultivated widely in India due to its specific agro-climatic requirement. Hence pyrethrins are mostly imported from Kenya. Therefore, the present study aims to develop a process for augmentation of pyrethrin contents in C. cinerariaefolium callus and establish the correlation between early knockdown effects through docking on grain storage insect. In vitro seedlings were used as explants to induce callus on MS medium with different concentrations of auxins and cytokinins. Pyrethrin extracted from the callus was estimated by RP-HPLC. In callus, total pyrethrin was found to be 17.5 µg/g, which is higher than that found in natural flowers of certain Pyrethrum cultivars. The concentrations of cinerin II, pyrethrin II and jasmoline II were quite high in callus grown on solid medium. Bio-efficacy of pyrethrum extracts of flower and callus on insect Tribolium sp., showed higher repellency and early knock-down effect when compared with pure compound pestanal. Further, the rapid knockdown effect of all pyrethrins components was established by molecular docking studies targeting NavMS Sodium Channel Pore receptor docking followed by multiple ligands simultaneous docking, performed to investigate the concurrent binding of different combinations of pyrethrin. Among the six pyrethrin components, the pyrethrin I and II were found to be a more efficient, binding more firmly to the target, exhibiting higher possibilities of insecticidal effect by an early knockdown mechanism.

Increasing the quantity of natural folates in plant foods is recently gaining significant interest, owing to their acute deficiencies in various populations. This study observed that foliar salicylic acid treatment enhanced the accumulation of folates in Arabidopsis, which correlated with the increase in a folate binding protein (FBP) and the expression of mRNA of a putative folate binding protein At5G27830. A protein band corresponding to ∼43 kDa was observed after resolving the affinity-purified protein on SDS-PAGE, and the partial amino acid sequence indicated that the protein is indeed At5G27830. Docking studies performed with At5G27830 confirmed specific binding of folic acid to predicted site. Heterologous expression of At5G27830 in the yeast resulted in significant uptake and accumulation of folic acid in cells. This novel study of a plant FBP will be useful for folate metabolic engineering of a wide range of crops.

Coriander (Coriandrum sativum L.), a commonly used annual herb that accumulates carotenoids upon methyl jasmonate (MeJA) treatment, provides an excellent model to investigate carotenogenesis and gene regulation. To explore key mechanisms involved in enhancing carotenoids, transcriptional expression profile of ten carotenogenic genes in the presence of MeJA and various gene specific inhibitors were investigated. Foliar application of MeJA (10 μM) increased expression levels of CsPDS (phytoene desaturase), CsZDS (ς-carotene desaturase), CsCHYE (carotene e - hydroxylase) and CsLCYE (lycopene β-cyclase) genes, and their transcript levels were strongly associated with carotenoid content, where, three days after treatment, 3.9 & 6.1 fold increase was observed for β-carotene and lutein respectively. The regulatory effect of key genes, CsPDS, CsZDS, CsLCYE and LCYB were further confirmed by using gene-specific inhibitors fosmidomycin, norflurazon and amitrol. Norflurazon- the phytoene desaturation inhibitor leads to a decrease in β-carotene and lutein content correlated with CsPDS, CsZDS gene induction. Our results clearly demonstrate that MeJA induced-signalling network evokes carotenogenic genes, leading to the accumulation of carotenoids. This knowledge may help to develop precise strategies for remodelling carotenoid pathway so that desired levels of a particular carotenoid in leafy vegetables is achievable.

The present study reports the presence of folate binding proteins (FBPs) in the plants, coriander and Arabidopsis, and their contributions toward folate enhancement. After observing that salicylic acid (SA) enhanced the accumulation of folates in coriander, a study was conducted in Arabidopsis, where twofold increase in folates occurred in foliage upon SA treatment. For obtaining insights into genes involved in SA-induced folate accumulation, microarray data of responsive genes in Arabidopsis were screened. Based on the expression profiles, 19 genes were further analysed by qPCR. The results revealed that folate biosynthetic genes were largely down-regulated, whereas a gene of a putative folate-binding protein (FPB) was up-regulated, which correlated with a significant increase of FPBs in foliage. This new information on a plant FBP appears useful for metabolic engineering of a wide range of crops to enhance the content and stability of the folates during post-harvest storage.

Foliage of coriander crop is a rich source of pro-vitamin-A carotenoids and phenolics of relevance to human health. Foliar-application of plant growth regulators e methyl jasmonate and salicylic acid, differentially elicited total carotenoids, b-carotene, lutein, chlorophylls, total phenolics and chlorogenic acid in coriander, GS4 Multicut and Mahak, the cultivars with high and low carotenoids respectively. Carotenoids and total phenolics increased 6.8 and 3 folds respectively when treated with methyl jasmonate (10 mmol/L), whereas salicylic acid (500 mmol/L) showed 5.4 and 3.5 folds of respective compounds. These treatments also enhanced levels of b-carotene, lutein, chlorophylls and chlorogenic acid, as observed by HPLC/MS analyses. Carotenoid and phenolic extracts of the best treatments showed significant increase in hydroxyl and superoxide radical scavenging antioxidant activities compared with controls. The observations made here indicate that the precise use of plant growth regulators is a simple method for naturally augmenting the nutritionally important compounds in coriander crop.

Since vitamin A deficiency is prevalent in many developing countries, we sought to focus research on local, affordable and well-accepted sources of provitamin A carotenoids. As dessert bananas are consumed fresh round the year and processed as products, this study investigated whether postclimacteric biochemical changes are linked to carotenoid degradation in four Indian varieties, one commercial (Cavendish, AAA), one Red banana (genome AAA) and two locally-important ones (genome AAB). Despite large differences in their ripening characteristics, textural loss was lesser in AABs than AAAs. High levels of carotenoids (21.0 mg/g FW), b-carotene (9.14 mg/g FW) and a-carotene (9.32 mg/g FW) were found in Red banana accounting for retinol activity equivalent of 114 mg/100 g FW. The carotenoid levels were lower in two local varieties and lowest in Cavendish, with no post-climacteric loss. Dry grits, prepared using Red banana pulp, milk powder and sugar, retained about 70% carotenoids and appeared useful in confectionaries.

Carotenoids and anthocyanins from floral petals of Delonix regia (Fabaceae) were isolated and characterized. Astaxanthin, a ketocarotenoid and anthocyanins — Peonidin-3- O -glucoside and Petunidin-3- o -acetyl-glucoside were newly identified by HPLC-MS. On 100 g dry weight basis, anthocyanin content was 830 mg in fresh and 580 mg in oven dried petals and 30 mg of β-carotene content in a total of 69 mg of carotenoids. This study has demonstrated that floral petals of D . regia are rich in unusual combination of biologically active carotenoids and anthocyanins, particularly cyanidin-3- O -rutinoside (800 mg/100 g DW), holding a great promise for food and pharmaceutical applications. Since astaxanthin is rarely found in higher plants, D. regia appears interesting for gene discovery for understanding of ketocarotenoid biosynthesis in higher plants.

Although populations of several tropical countries are under severe vitamin-A deficiency, traditional sources of pro-vitamin-A carotenoids have not been exploited due to the lack of relevant research data. In this study, ten commercial varieties of coriander (Coriandrum sativum L.), grown at identical conditions, were evaluated for carotenoids, their bio-efficacy and stability during drying, with the main emphasis on β-carotene (vitamin-A precursor) analysis by HPLC-MS. In all varieties, β-carotene content was higher in foliage at mature stage, than in seedlings and seeds. Variety GS4 Multicut produced highest biomass (6.18 ± 0.73 g/plant), total carotenoids (217.50 ± 5.6 mg/100 g DW) and β-carotene (73.64 ± 0.3 mg/100 g DW) at pre-flowering stage. Carotenoids extract showed a high antioxidant activity with IC50 value of 14.29 ± 1.68 μg/ml, scavenging hydroxyl radicals and rendering higher protection to DNA than by standard gallic acid (IC50 = 357.21 ± 4.29). Microwave drying of foliage was rapid with better retention of pigments, high intactness of trans-β-carotene and higher extractability of pigments when compared with oven drying.

To arrive at an appropriate bioreactor design and in situ recovery of the products, red beet hairy roots were used as a model system where the levels of betalain pigments (betacyanins and betaxanthins) were followed as secondary metabolite and the peroxidase enzyme as primary metabolite. Medium volume and other kinetic parameters were found to play significant roles by way of directly affecting the biomass yield rather than a specific metabolite. The hydrodynamic stress created on the roots by large culture volume could be minimized by pulse-feeding of medium in shake-flasks; and by separating the biomass chamber from the aerated medium reservoir in circulatory fed-batch bioreactor. Accordingly the bioreactor was modified to provide anchorage and air-enrichment chamber which resulted in higher formation of both the metabolites than in shake-flasks. Various down-stream processing aspects such as in situ release of pigments by non-destructive methods, followed by adsorption through a column and recovery by desorption were optimized for betalains. A strategy for simultaneous recovery of pigment and peroxidase was worked out using aqueous two phase extraction (ATPE).

An intracellular peroxidase (POD) produced by genetically transformed root cultures of red beet (Beta vulgaris L.) was purified using a combination of (NH4)2SO4 fractionation and ion exchange chromatography resulting in 15-fold enhancement of activity. This enzyme exhibited highest activity (10,500 U mg−1 protein) and stability at pH 5.0 and retained over 70% of the activity for 20 min at 70 °C where horseradish peroxidase (HRP) – a vastly used commercial source, had lost its activity after 11 min. The purified enzyme showed highest preference for H2O2 as the substrate (Km value of 0.1). Among the H donors, the enzyme appeared to have affinity in the order of orthodianisidine > 2,2′-azino-bis(3-ethylbenz-thiazoline)-6-sulfonic acid > guaiacol. The purified POD was completely and competitively inhibited by periodate ( HIO 6 - , Ki = 0.2 mM) whereas sodium azide (NaN3) was a non-competitive inhibitor. The purified POD had a molecular mass of 45 kDa as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and activity staining. This is the first report describing purification and characterization of POD from red beet hairy roots showing its better efficacy than commercial HRP.

Within 8 days of harvest, fruits of Capsium annum showed striking changes in texture when ripened at room temperature. Physiologically, they showed a significant weight loss and organoleptically, a change in textural firmness which was evident microscopically, as extensive cellular damage. The associated biochemical changes during ripening were: (1) an increase in free-sugar levels, (2) an increase in in situ hydrolysis of some hemicellulose fractions (Hem a, b and c) and (3) a general increase in the activity of cellulase, α-mannosidase, laminarinase, polygalacturanase, galactanase, mannanase, β-galactosidase and hemicellulase (HCe) activity on Hem b and c. In contrast the activity of xylanase, pectin methyl esterase and HCe on Hem a decreased during ripening. Cold storage (8°C) held textural changes in check, resulting in a longer shelf-life for cold-stored fruits compared to fruits stored at room temperature.

The presence of intensely colored hydrophilic nitrogenous betalain pigments, abundance of health-promoting compounds, growth-linked pigment-laden vacuoles in their cells and the possibility of quantitative regulation of pigment molecules have all made red beet cultured cells both an experimental model for studying cellular physiologies and a valuable source of various nutraceutical compounds. Compared with many other fruit/vegetable crops and sugar beets, studies targeted at developing in vitro regeneration protocols for varietal improvements and exploiting cell cultures for other biotechnological applications have not received much importance in red beet. With a focus on classic attempts made towards using cultured cells and organs for understanding growth, development and pigment biosynthesis-related physiologies, this chapter discusses aspects of newer technologies where cultured cells of Beta vulgaris may find applications.

Triggering cultured plant cells and organs to synthesize the highest possible extent of a particular metabolite is an advantage for its industrial-scale production. However, product recovery by smart techniques is equally important for the commercial success of the process. Considering the possibilities of in situ and ex situ product extraction methods, a large number of studies have focused on different modes of recovery of metabolites where intactness of molecules and their further stabilities have posed technological challenges. In red beet hairy roots, where chiefly betalains are of significance, reverse sequestration of vacuolar pigments into the cell exterior was accomplished by driving forces of both physical and chemical nature. Subsequent coupling technologies, such as pigment concentration by ex situ adsorption and simultaneous separation into red and yellow compounds during desorption, have also been successfully applied. Experiments conducted at bench-scale to standardize several unit operations were found adoptable for continuous process when such units were integrated. This chapter brings together research attempts made towards the recovery of betalains as well as the progress made towards developing strategic processes for the simultaneous recovery of betalains and peroxidase enzymes from red beet hairy roots grown in specialized bioreactors.

The invention of hairy root induction from various higher plants has ­provided a new set of hopes for using such organs in vitro as an alternative to cell cultures, chiefly because of their genetic stabilities that impart them high biochemical consistencies. Several research groups characterized different types of red beet hairy root clones, their scaled-up performances as well as their applications for various basic studies. Rather than cell cultures, hairy roots of red beet have attracted the attention of more number of research groups, probably because of their genetic aspects, spectacular colors, various morphologies, clonal stability and for other technological challenges associated with their scale-up and product recovery. The astonishingly variable responses of a cultivar of red beet (Ruby Queen) to different strains of Agrobacterium rhizogenes and the variable spectrum of morpho-physiological responses to nutrient components make red beet an ever interesting material for genetic as well as physiological studies, as discussed in this chapter. The fact that higher plants can transcribe animal genes and perfectly translate them into functional proteins has attracted newer opportunities for obtaining boundless number of important therapeutic proteins from cultured plant cells and organs. Hairy roots are often chosen for such purposes because of their consistent performances under fully manageable in vitro conditions. Many opportunities could also be realized with red beet hairy roots.

While Chap. 1 of this book provides an overview of what has been researched in red beet, this chapter tries to put red beet into the newer arena of diverting its current progress towards newer technologies and applications. Beets have unlimited applications, from food, fodder, fuel and pharmaceutical to ornamentals and environmental cleansing agents; this means that the allied technologies span from moderate to very high-tech ventures. Scientifically, as a model system, beet has contributed continuously to our knowledge of cellular physiologies of primary metabolism, energy conservation in the form of sugar synthesis and sequestration processes of primary and secondary metabolites. In the field of genetics, their ever-diversifying nature and amazing adaptability to newer environments have mesmerized scientists. Red beet occupies a position among the top ten vegetables for its antioxidant capacity, cancer-prevention activities and instant blood pressure control. However, it is essential to supplement the current knowledge with innovative scientific methods in terms of validation, characterization and further onward integration of processes through advanced mechanotronics to develop mainstream food products. Treating in vitro cultures and normal beet plant with innovative biotechnologies such as metabolic engineering and genetic modification is expected to significantly improve the sustainable production of a wide array of food, pharmaceuticals and bio-energy products. To realize these potentials, the probable technological leaps that are needed are discussed in this chapter.

Research on red beet has increased rapidly in the last decade owing to the presence of brightly colored water-soluble pigments complemented by its richness of antioxidants, neuro-stimulators and strong anti-hypertensive and anti-cancer effects. Apart from their increasing traditional applications in food and pharmaceutical products, betalains have found newer applications such as for developing solar cells and anti-ageing formulations. While the visible presence of vacuolar pigments has made the tissues of red beet a model system for studying several vacuole-related cellular physiologies, the material is ideal for developing color-extraction techniques and related engineering aspects. Although its derivative variety – the sugar beet – has attracted great attention because of its capacity to accumulate high sugar content, similar emphasis has never been placed on red beet. The modern knowledge and molecular techniques of genomics, proteomics and metabolomics have not been applied efficiently for improving existing nutraceuticals within the plant or for identifying hitherto unexplored biomolecules. The present chapter provides an overview of recent biotechnological research developments on red beet, highlighting the important research areas worth addressing in the near future.

Enzymes are natural biocatalysts that initiate and accelerate a large ­number of biochemical reactions in living cells. The fact that an isolated enzyme could also accomplish specific reactions outside the cell has resulted in an enormous demand for industrial-scale production of different enzymes from microbes and cultured plant cells/organs. The soluble protein of Beta vulgaris was observed to display high activities of several enzymes of commercial importance, of which, type III peroxidases (POD) (EC 1.11.1.7), are interesting. These PODs are encoded by multigenic families in land plants, where they are involved in several important physiological, developmental and ecological processes. Because of their versatile functionalities, a wide range of chemicals can be modified by dual catalytic activity of POD (oxidoreductase) and, therefore, are useful for several novel applications. Presently, horseradish is sourced for high-quality POD for biochemical/clinical applications, whereas certain agricultural wastes/by-products have been suggested for commercial applications, although with limitations associated with difficulties in their purification. Alternatively, cultured plant cells and hairy roots have recently attracted profound attention. Cultured red beet hairy roots (RBHR) exhibit massive activities of PODs with some isomers released directly into the medium. The characteristics of RBHR POD were found comparable with those of horseradish peroxidase (HRP), and hence can be similarly used in reagents for clinical diagnosis, for tracking various ­biochemical events in laboratory experiments and for pollution monitoring. This chapter provides an overview of recent advances made in the identification and characterization of different enzymes, particularly POD and their commercial applicability. Other presumed/hypothetical applications and research trends in this direction are also discussed.

Although pigments of biological origin are intensely researched for their market potentials and health benefits, their stability, from the maturity status of the source material to their processing and products into which the pigments are incorporated and the storage of those products, is shrouded with many problems. Both extrinsic and intrinsic factors affect the prospective arrays of applications of natural pigments such as betalains. Although the maturity of the red beet may not be the major quality trait in sourcing, the various processing steps, starting from the selection of the extraction medium, extraction conditions, product concentration, storage, transportation and incorporation into products, are huge tasks. The extrinsic factors affecting betalain stability include oxygen, temperature, pH, light and chemicals of processing and food products. On the other hand, the intrinsic factors in the red beet, apart from the quality of the source material, are mainly enzymes: β-glucosidases, polyphenoloxidases (PPOs) and peroxidases (PODs). The current chapter is a compilation of research progress made in understanding the factors affecting the stability of betalains, the chemical changes taking place during degradation and their further fate. Improvements in processing/extraction techniques and storage conditions that impart stability to betalain pigments are discussed. Additionally, application of fermentation and other advanced processes used for the preparation of pigments and food formulations are discussed.

Ethylene plays a key role in promoting fruit ripening, so altering its biosynthesis/signaling could be an important means to delay this process. Nitric oxide (NO)-generated signals are now being shown to regulate ethylene pathways. NO signals have been shown to transcriptionally repress the expression of genes involved in ethylene biosynthesis enzymes and post-translationally modify methionine adenosyl transferase (MAT) activity through S-nitrosylation to reduce the availably of methyl groups required to produce ethylene. Additionally, NO cross-talks with plant hormones and other signal molecules and act to orchestrate the suppression of ethylene effects by modulating enzymes/proteins that are generally triggered by ethylene signaling at post-climacteric stage. Thus, medication of endogenous NO production is suggested as a strategy to postpone the climacteric stage of many tropical fruits.

Folate (vitamin B9) content was evaluated in 10 varieties of coriander with the aim of enhancing its concentration and stability, because of three reasons: 1) coriander is among a few widely used greens in the world and suits many cuisines, 2) folate deficiency is prevalent in developing countries causing anaemia, infant mortality and neural tube closure defects, and 3) natural folate is preferred due to doubts about health risks associated with the synthetic form. In C. sativum, the highest folate content of 1,577 μg/100 g DW was found in var. GS4 Multicut foliage of mature plants (marketable stage) with an insignificantly higher content (1,599.74 μg/100 g DW) at flowering, which is a stage not preferred in markets. In callus cultures treated with plant growth regulators (GRs) (6-benzylaminopurine, kinetin and abscisic acid) substantial increase in folate occurred after 6 h, whereas elicitors (methyl jasmonate and salicylic acid) caused rapid 2-fold increase of folate, particularly in response to salicylic acid. Based on these observations, foliar applications were done for in vivo plants, where salicylic acid (250 μM, 24 h) also enhanced folate level by 2-folds (3,112.33 μg/100 g DW), although the content varied with diurnal rhythms. Stability of folates in treated coriander foliage was 10 % higher than in untreated foliage when stored at 25 °C and 4 °C. This study has established for the first time that coriander foliage is rich in folates, which can be doubled by elicitation and impart 10 % more stability than control during processing and storage.

Monocots (monocotyledonous plants) are one of the two major divisions of flowering plants, and are characterized by having parallel-veined leaves and an embryo with a single cotyledon. Techniques of tissue and cell culture have been successfully applied to a wide range of monocot species, which include cereals and other grasses, lilies, orchids, and palms. The techniques described in this article include callus culture, cell suspension culture, regeneration of plants, protoplast culture, anther and pollen culture, and shoot tip and meristem culture. The article also covers practical applications that use technologies based on tissue and cell cultures. Examples are the rapid propagation of clonal plants, and the production of doubled haploid plants for plant breeding. Genetic transformation has also been achieved through application of tissue and cell culture techniques to grasses and cereals, bananas, pineapples, onions, garlic, and duckweeds. A further application under development is the industrial production of secondary metabolites. Keywords: monocot; callus; somatic embryogenesis; protoplast; anther culture; microspore; haploid; micropropagation; bioreactor; genetic transformation

Monitoring ethylene is crucial in regulating post-harvest life of fruits. The concept of nitric oxide (NO) involvement in antagonizing ethylene is new. NO mediated physiologies casted through regulation of plant hormones are widely reported during developmental and stress chemistry having no direct link with ripening. Research in NO biology and understanding its interplay with other signal molecules in ripening fruits suggest ways of achieving greater synergies with NO applications. Experiments focused at convincingly demonstrating the involvement of NO in altering ripening-related ethylene profile of fruits, would help develop new processes for shelf life extension. This issue being the central theme of this review, the putative mechanisms of NO intricacies with other primary and secondary signals are hypothesized. The advantage of eliciting NO endogenously may open up various biotechnological opportunities for its precise delivery into the target tissues.

Syzygium cumini, Indian black plum or Java plum, is a rich source for anthocyanins (230 mg/100g DW) showing high antioxidant activity in vitro. In the following study it is further demonstrated that S. cumini peel extract rich in anthocyanins (SCA) offers considerable protection against carbon tetrachloride (CCl(4))-induced damage in rat hepatocytes. SCA itself being non-toxic to primary rat hepatocytes at concentrations ranging from 50 to 500 ppm, was found to suppress CCl(4)-induced LDH leakage by 54% at 50ppm, thereby improving the cell viability by 39%. The SCA significantly reversed the CCl(4) induced changes in cellular glutathione (GSH) level, lipid peroxidation and activity of the antioxidant enzyme glutathione peroxidase. Exposure of hepatocytes to SCA after CCl(4) treatment was found to elevate GSH and GPx activities by 2-folds, whereas the activities of catalase and superoxide dismutase were not significantly affected. The fruit pulp extract (SPE) was less effective in offering protection to rat hepatocytes, particularly in terms of total GSH content and a consequent increase in lipid peroxidation although the higher GPx activity suggests the probable involvement of GSH as a substrate for GPx. These observations suggest that the fruit peel extract of S. cumini, is largely responsible for the reversal of CCl(4)-induced oxidative damage in rat hepatocytes. Both peel and pulp extract appear to offer protection to rat hepatocytes through GPx along with other biological pathways independent of catalase and superoxide dismutase.

A large number of micropropagated plantlets of banana, Musa acuminata var. Nanjanagudu Rasabale (NR), that were developed from axillary shoot bud explants over 10 years ago were screened for genetic variation, if any, using RAPD (Random Amplified Polymorphic DNA) and ISSR (Inter-Simple Sequence Repeats) markers. Of the 4000 in vitro plantlets, 11 were used for screening that involved shoot cultures with distinct variation in morphological characteristics (morphotypes). Similarly, the mother maintained in the field was also subjected for genetic analysis. Out of the 50 RAPD and 25 ISSR primers screened, 30 RAPD and 5 ISSR primers produced totally 424 clear, distinct and reproducible band classes resulting in a total of 5088 bands where the banding patterns for each primer was highly uniform and comparable to the field-grown mother clone from which the cultures had been established. These results indicate that the micropropagation protocol developed by us for rapid in vitro multiplication is appropriate and applicable for clonal propagation of banana var. NR over a long period. This is the first report on the use of genetic markers to establish genetic fidelity of long-term micropropagated banana using RAPD and ISSR.

Background: Oxidation of low density lipoproteins and their further uptake by macrophages is known to result in the formation of foam cells, which are critical in the initiation of atherosclerosis through activation of inflammatory signalling cascades. Thus, powerful dietary antioxidants are receiving attention for the reversal of such pathological states. Materials and Methods: Extracts of Scoparia dulcis have been used as tea and health drinks with various health promoting effects. In the present study, we examined the reactive oxygen scavenging potential as well as anti-inflammatory and anti-atherogenic efficacies, using leaf extracts obtained after successive extraction with various solvents. Results: A methanol extract showed potent antioxidant activity with an IC 50 value of 570 μg/ml, caused hydrogen peroxide scavenging (28.9 µg/ml) and anti-inflammatory effects by improving human erythrocyte membrane stabilisation (about 86%). The methanol extract also efficiently inhibited lipid peroxidation and oxidation of low density lipoproteins, thus preventing foam cell formation in cultured RAW 264.7 cells. Furthermore, phytochemical screening of the extracts showed high accumulation of flavonoids. Conclusions: The foliar methanol extract of Scoparia dulcis has a strong anti-atherogenic potential and this property could be attributed maybe due to presence of flavonoids since HPLC analysis showed high concentrations of myricetin and rutin in the methanol extract.