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Many bacteria form mats at the air-liquid interface of static microcosms. These structures typically involve the secretion of exopolysaccharide(s), the production of which is often controlled by the secondary messenger c-di-GMP. Mechanisms of mat formation have been particularly well characterized in Pseudomonas fluorescens SBW25; mutations that lead to an increase in c-di-GMP production by diguanylate cyclases (WspR, AwsR, or MwsR) result in the secretion of cellulose, and mat formation. Here, we characterize and compare mat formation in two close relatives of SBW25: Pseudomonas simiae PICF7 and Pseudomonas fluorescens A506. We find that PICF7 – the strain more closely related to SBW25 – can form mats through mutations affecting the activity of the same three diguanylate cyclases as SBW25. However, instead of cellulose, these mutations activate the production of the Pel exopolysaccharide. We also provide evidence for at least two further – as yet uncharacterized – routes to PICF7 mat formation. P. fluorescens A506, while retaining the same mutational routes to mat formation as SBW25 and PICF7, forms mats by a semi-heritable mechanism that likely culminates in Pga and/or Psl production. Overall, our results demonstrate a high level of evolutionary flexibility in the molecular and structural routes to mat formation, even among close relatives.

The present investigation was conducted to find out the influence of different polyamines (PAs) viz. spermine (spm), spermidine (spd) and putrescine (put) and plant growth regulators (PGRs) on multiplication, rooting, callusing and regeneration in Aristolochia indica L. in vitro. Firstly, the A. indica plants were collected, surface sterilized and cultured in Schenk and Hildebrandt (SH) media fortified with various PGRs and PAs in different concentrations and combinations. SH media fortified with benzylaminopurine (BAP) (2.0 mg/l)+put (0.5 mM) and in another experiment, BAP (2.0 mg/l)+spd (1 mM) produced best results with 41.00 and 39.2 axillary shoots/ nodal explant respectively. Following 4-6 weeks of incubation, explants propagated in SH media augmented with various combinations and concentrations of BAP and kinetin (kin) (0.5, 1, 1.5 and 2 mg/l), spm, spd and put (0.5 and 1 mM) generated white friable callus. SH media supplemented with BAP (2.0 mg/l)+spd (0.5 mM) displayed best response with an average number of 47.5 base callus derived shoots . Following 6 weeks of incubation, SH+ indole-3-acetic acid (IAA) (1.0 mg/l)+spd (0.5 mM) resulted maximum average number (7) of roots per shoot. The genetic homogeneity of the mother plant (MP), hardened plant (HP) and in vitro regenerated plants was ascertained employing random-amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers. In this present study, in randomly selected A. indica plants, by using 6 ISSR and 5 RAPD primers, 63 scorable bands were derived, 59 of which were recorded as monomorphic with a degree of monomorphism of 90%. High-performance thin layer chromatography (HPTLC) revealed aristolochic acid (AA) content in in vitro grown A. indica roots and the roots from the mother plant (MP) as 6074.54 µg/g and 5891.14 µg/g respectively.

In the present report, the effect of methyl jasmonate (MJ) and salicyclic acid (SA) elicitation, on the indole alkaloid production from micropropagated culture of the endangered Ayurvedic medicinal plant Rauvolfia serpentina Benth. ex Kurz, was investigated. The highest shoot multiplication was found in Murashige and Skoog (MS) media augmented with BAP (2.0 mg/l) following 4 weeks of culture. MS media fortified with cytokinins produced nodal explant-derived nodular base callus (NBC)/ nodular meristemoids (NMs) following 6 weeks. Maximum root length was found in half strength MS basal (½ MSO) media and maximum number of roots per shoot was noted in ½ MS media augmented with indole-3-butyric acid (IBA) (1.5 mg/l). Clonal fidelity of the in vitro plants was assessed by 10 inter-simple sequence repeat (ISSR) primers of which only 3 primers (UBC-810, UBC-820, and UBC-827) produced clear and reproducible bands. The content wise variation of indole alkaloids (reserpine and ajmalicine), post elicitor (MJ and SA) treatment (0.5-2 mg/l) was quantified via high-performance thin layer chromatography (HPTLC). In vitro raised R. serpentina root accumulated highest amount of reserpine (0.456% and 0.440%) followed by 1.5 mg/l MJ and SA mediated elicitation respectively. Ajmalicine content of in vitro root, grown on culture elicitated with MJ (1.5 mg/l and 2 mg/l), was 0.261%. The ascorbate peroxidase (APX) activity was the highest in MJ (1.5 mg/l) treated micropropagated plantlets (0.86 EU/min/mg protein) and comparatively lesser in root samples (0.77 EU/min/mg protein) following 9 days of treatment. In all tested concentrations, SA treated plant sample exhibited strong superoxide dismutase (SOD) activity but the MJ and SA mediated elicitation caused sharp decrease in catalase (CAT) activity in all plant samples. In elicitor treated plant samples, the 1,1-diphenyl2-picrylhydrazyl (DPPH) radical scavenging activity (%) as well as total phenolics and flavonoids contents were marginally higher than the untreated ones. In vivo and in vitro grown R. serpentina root extracts showed best response against the four evaluated ATCC strains of bacteria.

Medicinally important steroid-based compound diosgenin is usually obtained from the secondary metabolic products of several plant species. Diosgenin has been proven as a prospective bioactive drug lead to the pharmaceutical industries as having anti-cancer activity, anti-microbial activity, anti-thrombic activity, anti-diabetic activity, cardioprotective activity, anti-inflammatory activity, osteoarthritis protective activity etc. Observing the multiple therapeutic values of this compound, scientists and chemists have become interested to discover alternative sources. Endophytic microorganisms possess the potentials producing prospective secondary metabolites. Some diosgenin producing endophytic fungi and bacteria are detected and reported by authors. Extraction and quantification of the respective secondary metabolite in a proper way is required initially for its large scale production. Regular involvement of advance biotechnological approaches plus industrial fermentation technology along with proper funding following government policy is necessary for further progress in this field. Exploration of a higher number of diosgenin producing endophytic strains will definitely increase the supply for social requisition in a cost-effective and environment-friendly manner as limiting the excessive exploitation of plant sources.

Several plant-derived neuroprotective nutraceuticals have shown their neuroprotective efficacy in various in vitro, in vivo, and clinical investigations. These molecules represent diverse types of chemical structures such as organosulfur, flavone, flavonol, alkaloid, polyphenol, and isothiocyanate. Neuroprotection offered by these molecules is mediated by antioxidation, anti-apoptosis, and anti-inflammation and by maintaining mitochondrial functionality. These nutraceuticals also prevent neurodegeneration by modulating several signaling pathways and gene expression. These include regulation of NOS via Akt and ERK, enhancement of mitochondrial function, downregulation of MAPK pathways, reducing convulsions, upregulating amyloidogenic route of brain APP processing, upregulating Keap1/Nrf2 pathway, and modulating NF-κB activation via the p38MAPK/PKC pathway and so on. Due to their ability to target multiple factors responsible for neuronal loss, they can serve as an excellent therapeutic agent to combat the complex nature of most of these neurodegenerative diseases. The present review focuses on the role of such botanical-derived nutraceuticals in the protection and prevention of several neurodegenerative diseases in vitro and in vivo mediated by their ability to modulate several signaling pathways, molecules, and gene expression to control various pathophysiological features of such diseases.

One of the most effective antitumor drugs is the Taxol (paclitaxel), a diterpenoid compound initially sequestered from the Pacific yew tree bark extract in the middle of 1960s. With a distinctive mode of action, paclitaxel is effective against several types of cancers, and hence there is an increasing demand for its worldwide supply. It is difficult to meet the present market requisite using existing industrial production approaches for the drug, i.e., total chemical synthesis and semi-synthesis by extracting paclitaxel precursors from the Pacific yew (Taxus brevifolia) tree species. Therefore, other methods have been meticulously explored, and one such encouraging strategy is the use of endophytic fungi. In this chapter, sources of endophytic fungi, their association with host plants, and their influence in producing the anticancer compound, paclitaxel, from their host plants are discussed. Also, paclitaxel-producing endophytic fungi and their possible scientific exploration are explained in detail.

Sex hormones have been found to play an intimate role with some of the cancers such as the breast-cancer, prostate-cancer, uterine-cancer, etc. The relation between the estrogen and breast-cancer h...

Endophyte is a broad term for microorganisms that colonize asymptomatically inside the healthy tissue of a host plant and maintain mutualistic association for the whole or part of their lifecycle. Many reports are found in the current literature on endophyte-mediated secondary metabolite production in diverse plant species. Piper is a genus belonging to family Piperaceae; it is commonly known as “Paan” and is cultivated extensively in Sri Lanka, India, Thailand, Taiwan, and other Southeast Asian countries. The parts of Piper utilized are leaves, roots, stems, stalks, and fruits. The plant has a large number of biomolecules that show diverse pharmacological activity. The leaves of Piper possess bioactivities with antitumor, antimutagenic, and antihelminthic properties. Piperine and piperidine are two such alkaloids found as the active compounds in the Piper. Few endophytes producing these compounds in Piper as secondary metabolites are reported and detailed in some existing literature. Further investigation needs to be undertaken for the identification of more such piperidine and piperine-producing fungi and survey on any bacterial endophytes. A survey of more such endophytes can assist in the commercial enrichment of these bioactive molecules and can limit the overuse of respective medicinal plant materials. The present review focuses on the utilization, extraction, and shortcomings of endophyte-mediated natural product biosynthesis in the major genera of Piper with a note on future perspectives.

Recent scientific investigations focused on drug discovery have accelerated the demand for novel pharmaceutical and agricultural products which are closely correlated with industrial applications. So, the present scenario of natural product-oriented research has expanded the combinatorial application of analytical chemistry, bioinformatics, and molecular biology to identify and isolate lead bioactive compounds from unexplored biological resources. The key features of natural selection attribute cumulatively in the functionality of any natural product, so secondary metabolites derived from specific organisms that exhibit exquisite niche specificity are favored over the common organism in ongoing pharmaceutical research. Endophytic fungi are ubiquitous, but their host infestation mechanism is quite interesting and evolutionarily very active, so the metabolic pathway regulating the mutualistic host-endophyte relationship possesses exclusive features and often biological applications. The research includes isolation, identification, and characterization of endophytic fungi as well as qualitative and quantitative estimation, structure elucidation, and screening of the structure-activity relationship of the biologically active compounds. However, biotope specificity and competitive vigor for nutrition, host, and survival of endophytic fungi are largely correlated with their biological activity, and are found to be superior to other microbes such as epiphytes. The precise balance between pathogenicity and mutualism is greatly monitored by the agonistic and antagonistic activity of fungal metabolites. Moreover, the influence of these metabolites boosts the immunological strength of the host and triggers a preventive reaction against herbivory or allelopathy in exchange for nutrients supplied to the microbial population. Interestingly, endophytes serve as a novel resource producing an array of bioactive compounds with great significance in basic research and medicine. Different biosynthetic pathways produce the secondary constituents, and they belong to diverse chemical classes including alkaloids, phenols, terpenes, quinones, isocoumarins, chromones, cytosporones, chalcone, steroids, xanthones, polyketides, and esters screened for a plethora of biological activities, that is, antibacterial, antifungal, insecticidal, and anticancer. Structure-activity relationship studies, key lead-based in vitro and in vivo investigations, and drug-metabolite synergism have largely elucidated the promising characteristics of endophytic fungi-derived metabolites to be the template of safe, economic, and bioactive therapeutics. However, authentication, screening, differentiation, clinical, and preclinical investigations are largely required before ensuring the medicinal efficacy of any metabolite derived from endophytic fungi.

Endophyte is a broad term covering a variety of microscopic organisms found within the living plant cells. Commonly they are different types of fungi and bacteria engaged in interactions with the plant host varying from symbiotic to pathogenic at various instances. Secondary metabolites are the diverse array of organic compounds produced by the plants or at times by some associated microorganisms essentially involved in a variety of defense-related activities of the plants. Several plant species have been reported with endophyte-mediated secondary metabolite production. A detailed examination and study of such secondary metabolites produced by the endophytic colonizers is helping to stress the medicinal properties of such products and ultimately to focus on unlocking new drug molecules. Asiaticoside and madecassoside are two such triterpenoid molecules of plant-origin found as the active compounds chiefly in the plant Centella asiatica. Few of the endophytes producing asiaticoside and madecassoside as secondary metabolites are being explored and are reported in different existing literatures. Different standardized protocols can be employed for the purpose of specific endophyte isolation and metabolite extraction. Further investigation needs to be undertaken for the identification of more asiaticoside and madecassoside producing fungi and also any bacterial endophytes. Industrial fermentation techniques can help in mass production of the compounds. Commercial enrichment of these bioactive molecules will help in curbing the overuse of the respective medicinal plant resources. Holistic knowledge about the wider distribution of endophytic microbial counterparts depending on various conditions of plant tissues can help in consistent grasping of the role of these organisms in synthesis of the bioactive metabolites.

The wisdom of traditional medicine has attained considerable appreciation and experimental research-based exposure in recent era. The emergence of the concept and practice of “complementary and alternative medicine” throughout the globe has considerably heightened the demand of medicinal plants. The trending approach of specific lead targeted drug-delivery system of modern medicine has utilized several plant-derived natural products and structural analog, some of which are under final stage of clinical trial. However, the bottlenecks regarding elucidation of mode of action rendered by active phytoconstituents and accelerated production of secondary metabolites through metabolic engineering are yet to be unveiled in many cases. The nonpathogenic symbiotic association between arbuscular mycorrhizal fungi (AMF) and plants has been reported for playing critical role in secondary metabolite accumulation. The mutualistic symbiosis in soil microflora not only influences plant growth and survival but also regulates various physiological features and stress responses. The probable mechanism includes altered stomatal conductance pattern, trichome density, photosynthesis rate, flowering, water and mineral uptake efficiency, plant growth regulator expression, and hormonal function. All these have contributed to cumulative production of secondary metabolites, viz., artemissin, glycyrrhizin, liquiritin, hypericin, pseudohypericin, and hyperforin, and enhanced accumulation is reported. The promising role of medicinal plant and AMF symbiosis in bioharvesting of natural products is an alternative and sustainable approach. The intensified plant biomass production is another positive outcome of this mutualistic association useful to cope with the industrial demand. This review is aimed to decipher the constructive effect of AMF symbiosis on medicinal plants, possible mechanism of bioactive compound accumulation under AMF association and degree of mutualistic effect under variable experimental conditions.

Cellular transport of water, i.e., essential for cell survival, takes place through a specialized water channel, referred to as an aquaporin (AQP). It falls under the category of the membrane intrinsic protein (MIP) superfamily and possesses several isoforms. AQP functions are directly related to an osmotic adjustment of plants facing different types of stresses. PIPs are the conserved ones among plant AQP subfamilies as found in most of the plant groups. About 30 kDa-sized monomers constitute the tetrameric structure of AQPs. Six transmembrane α-helices constitute the water transport channel where NPA, AEFL, and HW[V/I][F/Y]WXGP are the conserved sequences. Rapid water movement through this water channel occurs as a single-file configuration of water by means of channel selectivity with respective pore size. Specialized alignment of water molecules along with dipole charges plays a significant role in maintaining this water conduction. Basically, water stress is one of the substantial reasons for creating osmotic imbalances. Plasma membrane intrinsic proteins (PIPs) and tonoplast intrinsic proteins (TIPs) are expressed in most of the plants with deficiency of optimum water content for normal physiological activities. Each type of biotic and abiotic stress condition eventually causes cell-damaging osmotic stress. There are different factors like protons (H +), divalent cations, pH status, reactive oxygen species (ROS), hormones, phosphorylation, cellular trafficking, etc., which regulate the expression of AQPs in response to osmotic imbalance by different mechanisms. Presently, study of the role of AQPs in osmoregulation is very important in advanced research. Moreover, a multidirectional investigation is essential to answer questions regarding unrevealed issues in this area of plant physiology.

A specialized group of aliphatic polycations is referred to as polyamines distributed ubiquitously in prokaryotic and eukaryotic organisms. Free polyamines as well as conjugated polyamines are found in living cells. In plants, polyamines are synthesized from arginine via two alternative pathways. Plants have well-organized transport system for polyamine conduction. Among the wide range of physiological functions of polyamines, stress response is an important one. Plants have evolved a variety of mechanisms to recognize distinct stimuli for the alteration of the gene expression in response to different types of stresses (Hatmi et al. Osmotic stress and ABA affect immune response and susceptibility of grapevine berries to gray mold by priming polyamine accumulation. Front Plant Sci 65:75–88. https://doi.org/10.3389/fpls.2018.01010, 2018). Often, partially overlapping sets of responses are activated in different stress conditions, and several points of crosstalk exist between abiotic and biotic stress responses. Rice, an important food grain of South Asian countries, has been confronted with several stresses in the field of agriculture. Destructive pathogenic attack is one of the major challenges for their survival and good production. Apart from the conventional chemical treatment, modulation of genes for polyamine biosynthesis and expression might be a worthwhile means of solution for this problem. Considering the preventive role of polyamines during microbial infection, scientists are now trying to develop resistant varieties with the help of genetic engineering. In the present review, some relevant aspects are talked over to find out some cues about the detailing of the respective gene expression regarding this particular issue.

Bacopa monnieri (L.) Wettst. (Scrophulariaceae), commonly known as water hyssop, is an extensively used herb in Ayurveda. The bioactive phyto-constituents like the dammarane-type triterpenoid saponins such as bacosides A, B, and C were reported mostly for neuroprotective, nootropic, and memory-enhancing properties. Furthermore, B. monnieri also acts as a natural antioxidant, which can ameliorate morphine dependence, memory deficit in epilepsy, hepatocarcinogenesis, hepatotoxicity, β-amyloid cytotoxicity, inflammation, and oxidative stress (Singh et al., Physiol Plant. 2019). The neuroprotective role of the plant was manifested against neurodegenerative disorders like Parkinson’s disease (PD), Alzheimer’s disease (AD)-associated dementia, attention-deficit hyperactivity disorder in children, and anxiety. Somer report also found the traces of heavy metals in various species of Bacopa monnieri. Inadequate knowledge regarding underlying mechanism of neuroprotection and associated systematic structure-activity relationship (SAR) studies and development of semisynthetic derivatives of saponins are of high importance to facilitate rational designing of novel drugs based on leads from bacopasaponins. This review systematically summarizes the origin, analysis of the pharmacotherapeutic properties, and structural significance of bioactivities exerted by the bacopasaponins. Moreover, future research arenas, lacunae in the present understanding, are also highlighted in this work. Together, this book chapter may further direct to the synthetic optimization of bacopasaponins as lead compounds for the designing of efficacious and clinically acceptable analogues.

Huntington's disease (HD) is an incurable, chronic, progressive, and autosomal-dominant genetic neurodegenerative disorder manifested by abnormal involuntary and voluntary movements, cognitive, and psychiatric disruptions linked with corticostriatal neuronal loss. HD is one of the deadliest diseases commonly affecting older people and the present treatment offers only systematic relief without hindering the onset or ameliorating the disease. 3-Nitropropionic acid (3-NP) treatment mimics HD pathology via striatal degeneration leading to motor and cognitive anomalies. Therefore, striatal neurodegeneration involving a 3-NP model using transgenic animals and expressing mutant proteins is commonly used in preclinical investigations in order to elucidate HD-pathology and explore possible anti-HD therapeutics. In this present review, a number of plant-derived natural products are reported on the basis of their ability as disease-modifying agents active against HD-pathology in various neurotoxic and transgenic animal models via biochemical and molecular modulations of different signaling pathways commonly involving mitochondrial and oxidative stress. Anti-HD activity has been observed for α-mangostin, astragalan, berberine, celastrol, curcumin, galantamine, ginsenosides, hesperidin, lycopene, melatonin, onjisaponin b, protopanaxtriol, resveratrol, S-allylcysteine, sesamol, spermidine, vanillin, etc. These natural compounds alleviated disease pathology via retarding motor dysfunction, autophagy, mitochondrial dysfunction, lipid peroxidation, neuroinflammation, striatal toxicity, and also by promoting antioxidation, mutant protein degradation, motor and cognitive functions, behavioral improvement via modulation of biochemical and molecular signaling pathways, viz., Keap1-Nrf2-ARE pathway, MAPKs and NF-κB pathways, ERK pathway, etc. Moreover, the complex nature and possible synergism of polyherbal formulations containing phytochemicals against the multifactorial nature of HD-pathogenesis have also been discussed. However, very few systematic structure–activity relationship studies have been performed in order to explain the underlying mechanism of action of the natural products against neurodegenerative disorders, such as HD. Limited animal models and overdependence on cellular models are considered as major constraints in evaluating anti-HD natural products. However, the advent of HD transgenic models expressing mutant proteins may facilitate the routine screening of probable anti-HD natural therapeutics besides explaining HD-pathogenesis and more efficacious treatment strategies.

Marine biodiversity is a great reservoir of various types of fascinating structures such as sponges, bryozoans, tunicates, and fungi. In the past few years, natural products from marine life have acquired the limelight in drug discovery as they reduce the burden and dependency on plants. Marine fungi have drawn the attention of the scientific community toward their medically important secondary metabolites. The exclusive evolution pattern and osmoregulatory mechanism have contributed to its significantly enriched chemical biodiversity. Many bioactive compounds, phenolics, and amino-aldehydes with novel carbon skeletons were discovered and the search for new metabolites as pharmaceutical leads is on the rise. Many novel natural products from marine fungi have been reported as promising therapeutic drugs. For example, simplicilliumtides A, E, G, and H were isolated from Simplicillium obclavatum, a deep sea-derived fungal strain. It showed weak cytotoxicity toward selective human leukemia cell lines. Chemical compounds are classified according to their biological activity such as antiviral, anticancer, and antibacterial. Biological activities are mainly focused on the areas of antibiotic and anticancer properties. However, other critical features such as cell cycle inhibition, phosphatase and kinase inhibition, radical scavenging, and antagonistic platelet activation are closely associated with the antiproliferative mechanism. A different kind of metabolite has been discovered from various sources of fungi such as sponges, algae, and mangroves. The vast diversity of fungi habitats has an impact on the biosynthesis of these products. Although there is proven significance of the active metabolites of marine fungi, none of them has been successfully established in the market. The aim of this review is to highlight different sources of potential anticancer natural products obtained from marine fungi.

Crocus sativus L. (common name: Saffron; family: Iridaceae) is an important flowering plant used extensively in spice and food coloring as well as a flavoring agent. Among 85 species reported under the genus Crocus, Saffron (C. sativus) is the most interesting and commercially important species. Saffron is a triploid (3n) and sterile herb propagated naturally by corms, originated from mother corms. In the traditional system of medicine, it has been reported widely for its profound therapeutic efficacy; viz. anti-depressant, aphrodisiac, analgesic and expectorants. Saffron stigma is the potent source of bioactive compounds and an essential marketed spice as well as a food colorant. The expensive spice, Saffron and its bioactive apocarotenoids are known for their therapeutic effects on neurodegenerative diseases exhibiting anti-convulsant, anti-depressant, anti-anxiety, anti-ischemia, anti-Parkinsons’, anti-Alzheimer’s and anti-nociceptive activities. The principle pigments of saffron are crocin, safranal, glycoside picrocrocin and crocetin. However, there has been little success in enhancing the levels of these bioactive apocarotenoids of commercial importance. The genetic study has shown that this plant represents variegated ploidy pattern and the occurrence of genetically heterogenous forms—indicating the possibility of clonal selection, mutation breeding and polyploidy induction in the development of new high yielding cultivars of C. sativus. Tissue culture is an alternative, sustainable and biotechnologically advance method for large scale production of infection free corm biomass of Crocus. This review illustrates therapeutic potential of saffron and its active phytoconstituents, their extraction method, analysis of genetic diversity, quality control assessment and sustainable production of bioactive compounds harvested from C. sativus.

Incorporation of green chemistry techniques in undergraduate (UG) laboratories has a great demand. The challenge is to select and modify the known fundamental reactions in a greener way to implement into UG laboratories. A practical, two-step synthesis of 4-bromoacetanilide from aniline through a greener approach is described. Design of the synthetic route is based on the fundamental concepts of green chemistry. It can be adapted in most of the UG laboratories, including those with limited facilities. In the first step, aniline is converted to acetanilide using Zn dust/Fe powder–acetic acid instead of conventional acetic anhydride. In the second step, acetanilide is brominated using ceric ammonium nitrate–KBr combination in ethanolic–aqueous medium instead of bromine. The overall concept of modification could be useful to teach students about the concept of green chemistry, functional group protection, aromatic electrophilic substitution, and laboratory techniques such as reaction setup, isolation, purifi...

Objectives: To understand the monophasic kinetic behavior of hemicellulose hydrolysis and determination of thermodynamic parameters involved in dilute acid pretreatment by tartaric acid. Methods/Statistical Analysis: Biomass samples from thatched roofs were collected and analyzed for cellulose, hemicellulose and lignin through Neutral Detergent Fibre (NDF), Acid Detergent Fibre (ADF) and Acid Detergent Lignin (ADL) methods. The ground biomass was hydrolysed with tartaric acid, saccharified applying cellulase, xylanase at different time/agitation speed for obtaining reducing sugar and finally fermented for ethanol yield. The kinetics of hemicellulose hydrolysis was critically studied in the present work. Findings: The maximum yield of xylose and reducing sugars after hydrolysis and saccharification at optimum conditions were 134 mg/g and 494.8 mg/g using tartaric acid as hydrolyzing media. Pichia stipitis was very effective for conversion of pentoses and hexoses during fermentation. The maximum ethanol yield of 25.1% using tartaric acid was obtained after fermentation. Overall, the present works depicts the introduction of a new hydrolytic agent, tartaric acid and a comprehensive view of the complete bio processing of waste rice straw to bioethanol. The amount of ethanol yield was from 17% to 25.1%. It was noticed that the ethanol content was directly proportional with the increase in age of the samples. An increasing trend of ethanol with time was visible until 9th hour. High ethanol yield was obtained in this study since Pichia stipitisstrain could utilize both hexose sugars and pentose sugars together. Applications/Improvements: Thatched rice straw roof can be better utilized for ethanol making with natural degradation of lignin due to aging instead of increasing environment pollution using significantly less synthetic enzymes.

Ethnopharmacological relevance Aristolochia indica L. (Aristolochiaceae) is a common medicinal plant described in many traditional medicine as well as in Ayurveda used against snakebites. Besides, the plant has also been reported traditionally against fever, rheumatic arthritis, madness, liver ailments, dyspepsia, oedema, leishmaniasis, leprosy, dysmenorrhoea, sexual diseases etc. The plant is known to contain its major bioactive constituent aristolochic acid (AA) known for its anti-snake venom, abortifacient, antimicrobial and antioxidant properties. Materials and methods This present work describes a validated, fast and reproducible high performance thin layer chromatography (HPTLC) method to estimate AA from the roots of 20 chemotypes of A. indica procured from 20 diverse geographical locations from the state of West Bengal, India. Further, an evidence-based approach was adopted to investigate the reported anti-venom activity of the aqueous extracts of the A. indica roots by assessing its phospholipase A2 (PLA2) inhibitory properties since PLA2 is a major component of many snake-venoms. Finally, the cytotoxicity and genotoxicity of the aqueous root extract of the Purulia (AI 1) chemotype were assessed at various concentrations using Allium cepa root meristematic cells. Results The highest amount of AA (7643.67 μg/g) was determined in the roots of A. indica chemotype collected from Purulia district followed by the chemotypes collected from Murshidabad, Jalpaiguri and Birbhum districts (7398.34, 7345.09 and 6809.97 μg/g respectively). This study not only determines AA in the plants to select pharmacologically elite chemotypes of A. indica, but it also identifies high AA producing A. indica for further domestication and propagation of the plants for pharmacological and industrial applications. The method was validated via analyzing inter-day and intra-day precision, repeatability, reproducibility, instrumental precision, limit of detection (LOD) and limit of quantification (LOQ) and specificity. Chemotypes with high AA content exhibited superior anti-PLA2 activity by selectively inhibiting human-group PLA2. Moreover, A. indica root extract significantly inhibited mitosis in Allium cepa root tips as a potent clastogen. Conclusions The present quick, reproducible and validated HPTLC method provides an easy tool to determine AA in natural A. indica plant populations as well as in food and dietary supplements, a potential antivenin at one hand and a possible cause of aristolochic acid nephropathy (AAN) at another. Besides, the cytotoxic and mitotoxic properties of the root extracts should be used with caution especially for oral administration.

Lignin is the principal impediment in the production of biofuel from different lignocellulosic sources through hydrolysis, saccharification and fermentation route. The two main types of treatment for lignin separation from the other main constituent plant materials, hemicellulose and cellulose, are biodegradation and the chemical degradation including base-catalyzed, acid-catalyzed, ionic liquids-assisted lignin depolymerization. Severe reaction conditions, such as high pressure, high temperature and extreme pH, are being in practice for chemical degradation and result in the requirement of specially designed reactors. This leads to high costs of facility and handling along with the inadvertent generation of toxins. Biological degradation seems to be widespread and cost effective if enzymes degrading lignin could be produced by isolation of fungi. Bacterial strains could also be prepared that produce the lignin-splitting enzyme laccase. The present article reviews the available processes for lignin degradation during lignocellulosic conversion of ethanol and discusses the research gaps in these fields.

Bryophytes, taxonomically placed between the algae and the pteridophytes, are divided into three classes such as Liverworts, Hornworts and Mosses. Indigenous use involves this small group of plants to treat various diseases. Bryophytes have been investigated pharmacologically for active biomolecules. Several constituents with therapeutic potential have been isolated, characterized and investigated for antibacterial, antifungal, antiviral, antioxidative, antiinflamatory and anticancerous efficacy. The present review deals with the literature covering the anticancerous potential of bryophytes. Apart from the examples of the compounds and the containing bryophyte genera, the authors have tried to include the examples of cancer cell lines on which the efficacy have been tested and the mode of action of certain cytotoxic agents. Crude extracts and isolated compounds from bryophytes were found to possess potent cytotoxic properties. Different types of terpenoids and bibenzyls have been reported among the most potent cytotoxic compounds. Most of these compounds were found to induce apoptosis by activating a number of genes and enzymes. Biochemical markers such as DNA fragmentation, nuclear condensation, proteolysis of poly (ADP-ribose) polymerase, activation of caspases, inhibition of antiapoptotic nuclear transcriptional factor-kappaB, activation of p38 mitogen-activated protein kinase etc. have been found to be associated with apoptotic and necrotic response. This review summarizes recent scientific findings and suggests further investigations to evaluate the cytotoxic efficacy of bryophytes.

Alkaloids are a diverse group of naturally occurring secondary compounds derived from amino acids or the process of transamination. Some synthetic compounds with similar structure are also called alkaloids. Alkaloids provide useful starting templates for new drug designing. The botanical family Apocynaceae (also known as Dogbane family) consists of almost 250 genera and 2000 species of plants of various habits. Apocynaceae is especially rich in bioactive alkaloids such as reserpine, ajmaline, ajmalicine, yohimbine, serpentine, deserpine, thevetin, oleanderin, vincristine, vinblastine, catharanthine, vindoline, tabernanthine, tabernaemontanine, ibogamine, neriifolin, neriocorin, echitamine, alstonine, and many more with biological and therapeutic significance. Alkaloids are significantly abundant in the genera Rauvolfia, Catharanthus, Alstonia, Tabernaemontana, Strophanthus etc. Indole, bisindole, terpenoid indole, β-carboline indole, monomeric indole, acridone, pregnane, and steroidal are the various types and subtypes of alkaloids isolated from the apocynaceous plants. The Catharanthus (Vinca) alkaloids consist of a group of almost 130 terpenoid indole alkaloids of high medicinal significance of which vinblastine has been marketed for about 50 years as an anticancer therapeutic and a true lead for anticancer drug discovery. Besides, Vinca alkaloids have also been used as hypoglycemic, against high blood pressure and as disinfectants. The antihypertensive indole alkaloid reserpine from the genus Rauvolfia has also exhibited profound activity against cancer cell lines. Since medicinal plants produce a number of secondary metabolites with curative properties, alkaloids are no exception in this regard. Plant alkaloids have exhibited diverse pharmacological and medicinal properties such as antihypertensive, cytotoxic, anti-inflammatory, vasorelaxant, uterotrophic, antiparasitic, antimicrobial, opioid analgesic, antifertility, antidiabetic, neuroprotective, acetylcholinesterase inhibitiory, inducible nitric oxide synthase inhibitory, muscle relaxation, and antitussive activities. Many of these alkaloids are also used in cancer chemotherapy. Bioactivity-guided isolation has led to characterization of alkaloid rich antipsychotic and cytotoxic constituents from Apocynaceae members. Unfortunately, little is known about the underlying mechanism of bioactivity, and very little systematic structure-activity relationship studies have been undertaken in this diverse class of natural product. Synergistic effects among closely related compounds may serve as a crucial factor in determining pharmacological properties of plant constituents. Therefore, information on structure-bioactivity relationships of alkaloids and their naturally occurring congeners and semisynthetic derivatives is of immense importance in facilitating rational designing of novel drugs based on leads from natural alkaloids. This review is focused on the origin, analysis of the pharmacological and medicinal properties, and structural significance of bioactivities exerted by the plant-derived alkaloids. Moreover, to unfold future research openings, lacunae in the present understanding are also highlighted. Together, this review may further direct to the synthetic optimization of alkaloid as lead compound for the development of efficacious and clinically applicable alkaloid analogues.

X-ray crystal structure shows that 3,5-dimethyl-1-(2-nitrophenyl)-1H-pyrazole (DNP) belongs to the rare class of helically twisted synthetic organic molecules. Hydrogenation of DNP gives 2-(3,5-dimethylpyrazole-1-yl)phenylamine (L) which on methylation yields [2-(3,5-dimethylpyrazole-1-yl)phenyl]dimethylamine (L'). Two Pd(II) complexes, PdLCl2 (1) and PdL'Cl-2 (2), are synthesized and characterized by NMR. X-ray crystallography reveals that 1 and 2 are unprecedented square planar complexes which possess well discernible helical twists. (C) 2007 Elsevier B.V. All rights reserved.

Various pyrazole-based P,N (2a–c) and N,N (3a–b) ligands have been synthesized. Using representative ligands, NiII, CoII, CuII, and CuI complexes have been prepared and structurally characterized by crystallography. During complexation of CoII and CuII salts, the phosphane part of the P,N ligand oxidized to phosphane oxide. For N,N donor ligands, a dimeric chloro-bridged NiII complex was obtained. NiII complex 4 is an active catalyst for ethylene oligomerization. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

The structure of the title compound, C 17 H 20 O 3 , a substituted cyclohexene system, has been determined. The high degree of disorder in various substituent moieties results in two different orientations of the molecule in the crystal lattice which have unequal occupancy factors. Lattice-energy calculations based on van der Waals attractive and repulsive potentials clearly show minima at the observed disordered positions. The difference in occupancy factors between the two molecular orientations can be explained from the relative values of lattice energies.

The structure of the title compound, C 17 H 20 O 3 , a substituted cyclohexene system, has been determined. The high degree of disorder in various substituent moieties results in two different orientations of the molecule in the crystal lattice which have unequal occupancy factors. Lattice-energy calculations based on van der Waals attractive and repulsive potentials clearly show minima at the observed disordered positions. The difference in occupancy factors between the two molecular orientations can be explained from the relative values of lattice energies.

Pyrazole-derived bidentate ligands (P,N-donor) with bulky substituents at the 3-position of the pyrazole, 1b–d, were used with Pd2(dba)3 to carry out efficient Suzuki coupling reactions with both aryl bromides and chlorides. Enhanced catalytic activity on account of steric crowding in the metal complex suggested participation of a chelated structure in the intermediate catalytic steps.

Various in vivo and in vitro pituitary-Leydig cell functions were examined in mature (5-8 mo) vs. old (22-25 mo) male Wistar rats. Old rats exhibited decreased serum concentrations of testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) (P less than 0.0025) but similar levels of prolactin (P less than 0.01) both before and 4 wk after castration. The in vitro release of LH, FSH, and free alpha-subunits was measured in primary cultures of dispersed anterior pituitary cells from both intact and castrated rats. During 48 h of incubation, basal secretion rates of the glycoproteins were decreased (P less than 0.001) from cells of both intact and castrated old rats. After stimulation with LH-releasing hormone (LRH) in single (10(-8) M) or multiple (10(-10) - 10(-7) M) doses, the total amounts of the glycoproteins secreted were also less from cells of both intact and castrated old rats. However, repeated measures analysis of variance revealed age-related hyporesponsivity to LRH stimulation only for LH secretion by cells from intact rats. The basal molar ratios of alpha/(LH + FSH) secreted by cells from intact but not castrated old rats were lower than those from cells of the corresponding mature rats. Moreover, after LRH stimulation (10(-10) - 10(-7) M), molar secretory ratios of alpha/(LH + FSH) decreased from cells of intact mature rats but increased from cells of intact old rats. These in vitro data suggest that the reduced serum LH and FSH levels in intact and castrated old male rats result in part from decreased secretion of these glycoproteins.(ABSTRACT TRUNCATED AT 250 WORDS)

Viable colonic epithelial cells from rats were isolated by a non-enzymatic procedure using EDTA. The isolated cells were fractionated by sedimentation through a 15% to 35% discontinuous Ficoll gradient to yield cells differing in proliferative capacity from three different density regions of the gradient. Glycoprotein synthesis of these fractionated cells was examined in terms of their ability to absorb and incorporate labeled glucosamine and fucose into trichloroacetic acid precipitable material. Glycoprotein synthesis was highest among cells with intermediate densities, banding in the middle of the gradient (Fraction II). Cytomorphological examination showed that these cells were predominantly goblet type.