Biochemistry

Background: Ascorbic acid (vitamin C, ascorbate) has been shown to protect cells against various types of oxidant injury at physiologically relevant concentrations. Vitamin C has been suggested as having both a preventative and therapeutic role in a number of pathologies when administered at much higher-than-recommended dietary allowance levels. This article reviews the scientific rational for intravenous vitamin C as a potential treatment for cancer.

This study was conducted to evaluate the hepatoprotective activity of
aqueous and ethanol extract of Mangifera-indica stem bark in paracetamolinduced
liver injury in winstar albino rats. Aqueous and ethanolic extracts of
M. indica stem bark at a dose of 200mg/kg were administered for 7 days to
rats in groups II and III respectively while vitamin C (200mg/kg) was given
as a standard antioxidant to group IV along with water and standard feed.
Groups I and V received water and standard feed for 7day. On the 8th day all
groups except group I received paracetamol at a dose of 2g/kg body weight
and all rats were sacrificed 12hrs after paracetamol administration. Serum
total protein (TP), albumin, aspartate transaminase (AST), alanine
transaminase (ALT) and alkaline phosphatase (ALP) were determined to
assess the effect of the extract on the paracetamol induced hepatic damage in
addition to hepatic antioxidant status. The ethanolic extract was found to be
more effective than the aqueous extract (200 mg/kg) in paracetamol induced
liver damage by decreasing the activity of serum enzymes AST, ALT and
ALP while increasing significantly (P<0.05) the levels of total proteins and
albumin. Glutathione (GSH), catalase (CAT) and superoxide dismutase
(SOD) activity were significantly increased (P<0.05) in the treated groups
while malondialdehyde (MDA) levels were reduced. From this studies it is
concluded that both aqueous and ethanol extract of M. indica stem bark
possesses hepatoprotective activity.

The Moringa plant provides a rich and rare combination of zeatin, quercetin, sitosterol, caffeoylquinic acid and kaempferol. In addition to its compelling water purifying powers and high nutritional value, M. oleifera is very important for its medicinal value. Various parts of this plant such as the leaves, roots, seed, bark, fruit, flowers and immature pods act as cardiac and circulatory stimulants, antipyretic, antitumor, anti-inflammatory, antiepileptic, diuretic, antiulcer, antispasmodic antihypertensive, cholesterol lowering, antidiabetic, antioxidant, antibacterial, hepatoprotective, and antifungal activities, and are being employed for the treatment of different ailments in the indigenous system of medicine, particularly in South Asia.

Madhuca longifolia (Mahua) belongs to family Sapotaceae. Madhuca commonly known as the Butter nut tree is a medium to large sized deciduous tree distributed in Nepal, India and Sri Lanka. Madhuca longifolia is a large tree, about 17m high with a large top. Mahua is a large, shady, deciduous tree doting much of the central Indian landscape, both wild and cultivated. Mahua seeds are of economic importance as they are good source of edible fats. Medicinal herbs are moving from fringe to mainstream use with a great number of people seeking remedies and health approaches free from side effects caused by synthetic chemicals. Madhuca longifolia is reported to contain sapogenins, triterpenoids, steroids, saponins, flavonoids and glycosides. It is used as spasmogenic, oxytocic, uterotonic, anti-bacterial, anti-implantation, anti-tumour, anti-progestational, antiestrogenic activity against menorrhagia and anti-cancer. This review contains the traditional uses of various parts of plant, Phytochemical constituent and different reported pharmacological activity.

AbstrAct It is a current concern in the wood preservation field to avoid the use of toxic chemicals and develop new technologies based on low environmental impact agents and sustainable principles. Under this expectation, an intended state-of-the-art is introduced on the application of natural products such as traditional tar and wood oils as well as tannins and plant extracts. A particular revision to heartwood chemical components is offered. The combined methods of using natural and chemical components are reviewed, considering as outstanding the mixtures of natural organic constituents with cooper and boron salts that seem to be under encouraging experimentation. Fungicides and anti-termite applications are commented as well the leaching problem of inorganic salts. Chemical modification of wood structure through the formation of adducts and the treatment with nanomaterials are promising tools that will change the actual view and performance of wood preservation techniques. resumen Una de las prioridades actuales en el campo de la preservación de madera es evitar el uso de materiales tóxicos, desarrollando nuevas tecnologías fundamentadas en principios sustentables y empleando agentes de bajo impacto ambiental. Con esta expectativa se plantea una revisión del estado del arte sobre la aplicación de productos naturales, tales como taninos, alquitrán, aceites y extractos vegetales. Se presenta en particular una revisión sobre los componentes químicos contenidos en el duramen de maderas naturalmente resistentes. Se analizan los métodos combinados de ingredientes naturales y químicos, resaltando las mezclas de componentes naturales orgánicos con sales de cobre y boro que parecen representar una opción experimental confiable. Se comentan también las aplicaciones fungicidas y anti termitas, así como los problemas de lixiviación de sales inorgánicas. Opciones como la modificación química de la madera vía la formación de aductos y por tratamiento con nanomateriales son procesos promisorios que cambiaran eventualmente la manera de ver y aplicar la tecnología actual de preservación de maderas.

ABSTRACT
This work was carried out to investigate the chemical/mineral composition of the water extract of zobo (Hibiscus sabdariffa) drink using the modern atomic absorption spectrophotometer. Zobo drink is a popular drink in the Nigeria, especially in the northern part of Nigeria. The result of the analysis indicated that the drink is high in vital mineral nutrients required for the healthy growth by humans and for the proper metabolic processes to be adequately maintained. Zobo drink is high, as indicated in the result, in iron – a major component of the human haemoglobin, when compared with other leaf like the popular vegetable leaf known as awa (Piper methysticum).

This study evaluates the percentage content of carbohydrate components present in sour sop pulp peels. The samples were washed and dried at 60oC for eighteen hours; this was done to prevent the volatilization of some components at higher temperatures. The carbohydrate components that were determined included starch, lignin, cellulose, hemicelluloses, holocellulose and reducing sugar. Standard methods were used to determine the various parameters. Results showed that starch, lignin, cellulose, hemicelluloses, holocellulose and reducing sugar had percentage concentrations of 0.25%, 14.7%, 20%, 15%, 34% and 14.3% respectively. This study shows that the peels of sour sop pulp have some industrial potentials especially in the production of paper and low cost ethanol.

, is an endemic resinous plant used in traditional medicine, perfume production, incenses, aroma therapy and cosmetic industry. Due to the high economic value, large-scale smuggling of G. walla from Sri Lanka has been practiced for a long time. Therefore, present study was undertaken to study the phytochemical and volatile oil components of G. walla. Phytochemical analysis of leaf, bark and stems were performed according to the methods described in WHO guidelines. Aerial parts were hydro-distilled in a Clevenger-type apparatus for 8 h. Oil was analyzed using GC-MS and identification of components of volatile oils was carried out based on retention indices and fragmentation patterns of the mass spectra. Phytochemical screening of leaf, stem and bark crude extracts of G. walla revealed the presence of tannins, saponins, steroid glycosides, flavonoids and alkaloids in all three parts tested. Thin layer chromatographic profiles observed under UV light at 366 nm exhibited higher number of spots in CH 2 Cl 2 extracts for all three parts followed by hexane and methanol fractions, respectively. Sky blue spot present in all three fractions [hexane (R f = 0.83), dichloromethane (R f = 0.66) and methanol (R f = 0.77)] of stem extracts was characteristic to the stem extract. The yield of the essential oils obtained from stem parts of G. walla was 0.20 ± 0.01%. Major constituents, which exist more than 1% in heartwood of G. walla oil, were gamma-selinene (72.49%), 3-Phenyl-2-butanone (2.04%), 3-pentanone (2.02%), betapatchoulene (1.37%) respectively. Present study reports the presence of preliminary phytochemicals, TLC finger prints and GC-MS analysis of essential oil of G.walla for the first time in Sri Lanka. Presence of high content of γselinene and β-patchoulene (73.86%) indicates potential for commercial production of world class perfume and other scented products.

Essential oils are complex mixtures isolated from aromatic plants which may possess antioxidant and anti-inflammatory activities of interest in thye food and cosmetic industries as well as in the human health field. In this work, a review was done on the most recent publications concerning their antioxidant and anti-inflammatory activities. At the same time a survey of the methods generally used for the evaluation of antioxidant activity and some of the mechanisms involved in the anti-inflammatory activities of essential oils are also reported.

Omega 3 fatty acids are issued from linolenic acid (18:3ω3). Nutritional interest about ω3 fatty acids has begun since the epidemiological studies of Dyerberg et al. have shown a relationship between consumption of marine fats and reduction of cardiovascular diseases. Long-chain ω3 fatty acids, mainly eicosapentaenoic (20:5ω3 or EPA) and docosahexaenoic (22:6ω3 or DHA) acids, are considered to be the main bioactive components in marine sources. Other studies have confirmed that consumption of fish ou EPA\\DHA supplements may reduce mortality in patients who have suffered from myocardial infarction. Beneficial effects of ω3 fatty acids are also recognized in inflammatory disorders. The main mechanism involved for those effects is assumed to be the interference between long-chain ω3 fatty acids and the arachidonic acid (AA) metabolism in blood and vascular cells. In those cells, AA may be released from membrane phospholipids by phospholipase A 2 and subsequently oxygenated into eicosanoids (overall called AA cascade). According to the cell, oxygenated products from AA include thromboxane (platelets), prostacyclin (endothelial cells) and leukotrienes (leukocytes). EPA and DHA can interfere with AA cascade by several ways to reduce the vascular risk. However, high intake of such fatty acids may increase lipid peroxidation and have deleterious effects, in particular in subjects suffering from oxidative stress, whereas law may exert "antioxidant" activity. We conclude that a moderate consumption of longchain ω3 fatty acids can protect against cardiovascular dysfunction.

Hairy root transformation has been widely adapted in plant laboratories to rapidly generate transgenic roots for biochemical and molecular analysis. We present hairy root transformations as a versatile and adaptable model system for a wide variety of undergraduate laboratory courses and research. This technique is easy, efficient, and fast making it an ideal tool for undergraduate teaching. Students in a biotechnology course successfully transformed soybean cotyledons with Agrobacterium rhizogenes strain K599 during laboratory sessions. The students introduced the green fluorescent protein (GFP) gene into soybean and observed hairy roots regeneration. After two weeks, 45% of the cotyledons developed roots. Of the roots that appeared after transformation, 55% expressed the GFP protein.

DNA computing is a new computing paradigm which uses bio-molecular as information storage media and biochemical tools as information processing operators. It has shows many successful and promising results for various applications. Since DNA reactions are probabilistic reactions, it can cause the different results for the same situations, which can be regarded as errors in the computation. To overcome the drawbacks, much works have focused to design the error-minimized DNA sequences to improve the reliability of DNA computing. In this research, Population-based ACO (P-ACO) is proposed to solve the DNA sequence optimization. P-ACO approach is a meta-heuristic algorithm that uses some ants to obtain the solutions based on the pheromone in their colony. The DNA sequence design problem is modelled by four nodes, representing four DNA bases (A, T, C, and G). The results from the proposed algorithm are compared with other sequence design methods, which are Genetic Algorithm (GA), and Mult...

he fossils described elsewhere in this issue probably left no descendants, are not very old, and were found on a remote island. Despite this, they are among the most outstanding discoveries in palaeoanthropology for half a century. The two papers concerned-by Brown et al. 1 and Morwood et al. 2-appear on pages 1055 and 1087 of this issue, and respectively describe the fossils and their archaeological context. The find is startling.It is of a pygmysized, small-brained hominin, which lived as recently as 18,000 years ago, and which was found on the island of Flores together with stone tools, dwarf elephants and Komodo dragons. Discoveries don't get better than that. The Flores fossils add a new and surprising twig to the hominin family tree, which diverged from the chimpanzee lineage about 7 million years ago. The first African hominins existed 7-1.2 million years ago, were 1-1.5 metres tall, walked upright on two legs (that is, were bipedal), and had chimpanzee-size brains. These early forms comprised as many as six genera and fourteen species, of which the australopithecines are the best known. By 2.5 million years ago, our own genus, Homo, had emerged, with its different body shape, slower growth, greater reliance on meat in the diet, and 'encephalization'-larger brains than expected for body size. These were the first hominins to make stone tools systematically and to colonize Eurasia. They include the familiar names of H. habilis, H. erectus, H. neanderthalensis and, finally, H. sapiens, which put in an appearance about 160,000 years ago. The new fossil is part of this Homo group (Fig. 1). Flores lies to the east of Java, and was probably never connected to the mainland. The presence of 800,000-year-old simple stone tools first attracted attention in 1998 (ref. 3), raising the controversial possibility that H. erectus had produced them and had crossed major sea barriers to reach Flores. Now we have the announcement of the discovery of an 18,000-year-old hominin skeleton from a cave, Liang Bua, on Flores. Although this date is more than 140,000 years after modern humans evolved in Africa, more than 25,000 years after H. sapiens reached Australia, and about 10,000 years after the last known Neanderthal, the

The use of microfluidic glass chips for continuous single-cell lysis and assay of internal-Galactosidase (-Gal) content is described. Cells were transported single file toward a Y-shaped mixing junction at which lytic agents were introduced by suction. Flow velocities of 100 and 40 m/s were used under protein denaturing [35 mM sodium dodecylsulfate (SDS)] and nondenaturing (0.1% Triton X-100) conditions, respectively. Complete and reproducible lysis of individual cells on-chip occurred within 30 s using Triton X-100 and 2 s when using SDS. Optimal concentrations of lysis and enzyme substrate reagents were determined using microtitre plate and chip-based procedures. Fluorescence peaks, due to the enzymatic product fluorescein mono-D-galactopyranoside (FMG), were detected downstream of the mixing and cell lysis point for the reaction of-Gal with 200 M of the fluorogenic substrate fluorescein-diD -galactopyranoside (FDG). FMG fluorescence was observed from cells preincubated with FDG off-chip then subsequently lysed on-chip with SDS. Unincubated cells were mixed on-chip with both FDG and Triton X-100, each individual cell generating FMG fluorescence downstream of the mixing point detected within 2 min of mixing. In contrast, viable cells incubated with FDG required 1 h or more in order to generate significant signal in a flow cytometer.

Telomeric DNA consists of G-and C-rich strands that are always polarized such that the G-rich strand extends past the 3' end of the duplex to form a 12-16-base overhang. These overhanging strands can self-associate in vitro to form intramolecular structures that have several unusual physical properties and at least one common feature, the presence of non-Watson-Crick G-G base pairs. The term "G-DNA" was coined for this class of structures . On the basis of gel electrophoresis, imino proton N M R , and circular dichroism (CD) results, we find that changing the counterions from sodium to potassium (in 20 m M phosphate buffers) specifically induces conformational transitions in the G-rich telomeric D N A from Tetrahymena, d(T2G4)4 (TET4), which results in a change from the intramolecular species to an apparent multistranded structure, accompanied by an increase in the melting temperature of the base pairs of > 2 5 O , as monitored by loss of the imino proton N M R signals. N M R semiselective spin-lattice relaxation rate measurements and HPLC size-exclusion chromatography studies show that in 20 m M potassium phosphate (pH 7) buffer (KP) TET4 is approximately twice the length of the form obtained in 20 m M sodium phosphate (pH 7) buffer (Nap) and that mixtures of Na+ and K+ produce mixtures of the two forms whose populations depend on the ratio of the cations. Since K+ and NH4+ are known to stabilize a parallel-stranded quadruplex structure of poly[r(I),], we infer that the multistranded structure is a quadruplex. Our results indicate that specific differences in ionic interactions can result in a switch in telomeric DNAs between intramolecular hairpin-like or quadruplex-containing species and intermolecular quadruplex structures, all of which involve G G base pairing interactions. We propose a model in which duplex or hairpin forms of G-DNA are folding intermediates in the formation of either 1-, 2-, or 4-stranded quadruplex structures. In this model monovalent cations stabilize the duplex and quadruplex forms via two distinct mechanisms, counterion condensation and octahedral coordination to the carbonyl groups in stacked planar guanine "quartet" base assemblies. Substituting one of the guanosine residues in each of the repeats of the Tetrahymena sequence to give the human telomeric DNA, d(T2AG,)4, results in less effective K+-dependent stabilization. Thus, the ion-dependent stabilization is attenuated by altering the sequence. Upon addition of the Watson-Crick (WC) complementary strand, only the Na+-stabilized structure dissociates quickly to form a W C double helix. This demonstrates that under some circumstances the K+-stabilized G-DNA structure can be kinetically preferred over W C DNA.

This paper presents researches regarding the content of essential oils, flavonoids, polyphenolic and phenolic compounds in leaf parsley from an organic culture and the methods of extraction used for determinations. The obtained results highlight the medicinal properties of parsley, both the alimentary and economic importance, as a vegetable aromatic plant used for human consumption worlwide.

The present work is in the technical field of plant extraction. More particularly, the work relates to the extraction of medicinal plants using liquid nitrogen in a closed environment. The principal objective of this work is to provide a new method of plant extraction using liquid nitrogen which is simple, safe and less time consuming as compared to the existing open method of plant extraction using liquid nitrogen. The plant used for the study was Cynodon dactylon (Linn.) Pers. The new method includes the steps of size reduction of the plant material, taking the plant material and solvent in culture tubes, closing the tubes properly and dipping these tubes into liquid nitrogen at below-196 °C, melting the frozen material inside the tubes and collecting the liquid extract. The new method of plant extraction avoids exposing liquid nitrogen in open environment and thus avoids the drawbacks of the available methods of plant extraction using liquid nitrogen in open environment.

Cystic fibrosis is the most common autosomal recessive potentially lethal hereditary disease. The disease is caused by mutations in the CFTR gene of the transmembrane peptide. CFTR, functioning as a cAMP-dependent chlorine channel, regulates chlorine and sodium channels, participates in water and ATP. As a result of a genetic defect, the secretion of the glands of external secretion thickens, its evacuation becomes more difficult, secondary changes occur in the organs.

X-ray microcomputed tomography (mCT) allows nondestructive visualisation of plant root systems within their soil environment and thus offers an alternative to the commonly used destructive methodologies for the examination of plant roots and their interaction with the surrounding soil. Various methods for the recovery of root system information from X-ray computed tomography (CT) image data have been presented in the literature. Detailed, ideally quantitative, evaluation is essential, in order to determine the accuracy and limitations of the proposed methods, and to allow potential users to make informed choices among them. This, however, is a complicated task. Three-dimensional ground truth data are expensive to produce and the complexity of X-ray CT data means that manually generated ground truth may not be definitive. Similarly, artificially generated data are not entirely representative of real samples. The aims of this work are to raise awareness of the evaluation problem and to propose experimental approaches that allow the performance of root extraction methods to be assessed, ultimately improving the techniques available. To illustrate the issues, tests are conducted using both artificially generated images and real data samples.

The antimicrobial peptide human α-defensin 5 (HD5) is expressed in Paneth cells, secretory epithelial cells in the small intestine. Unlike other characterized defensins, HD5 is stored in secretory vesicles as a propeptide. The storage quantities of HD5 are ∼90-450 µg per cm 2 of mucosal surface area, which is sufficient to generate microbicidal concentrations in the intestinal lumen. HD5 peptides isolated from the intestinal lumen are proteolytically processed forms-HD5(56-94) and HD5(63-94)-that are cleaved at the Arg 55 -Ala 56 and Arg 62 -Thr 63 sites, respectively.We show here that a specific pattern of trypsin isozymes is expressed in Paneth cells, that trypsin colocalizes with HD5 and that this protease can efficiently cleave HD5 propeptide to forms identical to those isolated in vivo. By acting as a prodefensin convertase in human Paneth cells, trypsin is involved in the regulation of innate immunity in the small intestine.

There is a need to develop efficient tools to prevent damage to marine ecosystems due to pollution. Since microalgae play a key role in marine ecosystems, they are considered potentially useful for quick and sensitive toxicity bioassays. In this study an integrative analysis has been carried out of the anti-oxidant enzyme activities of marine microalgae species. Three marine microalgae species (Cylindrotheca closterium, a benthic diatom; Phaeodactylum tricornutum, a diatom which has been used as model organism in toxicity bioassays; and Rhodomonas salina, a cryptophyceae which is considered to present a certain level of heterotrophy) were exposed to selected concentrations of three model pollutants: copper (5 and 10 mg L À 1 ), atrazine (25 and 50 mg L À 1 ) and Irgarol (0.5 and 1.0 mg L À 1 ). These pollutant concentrations are environmentally relevant for coastal ecosystems, and have been selected for checking the efficiency of the reactive oxygen intermediate (ROI) scavenging enzyme system of these organisms. Superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APx) and glutathione peroxidase (GPx) activities were measured at the end of 24 h exposure. The integrated biomarker response (IBR) indexin our case for oxidative stresshas been employed to evaluate the ROI-scavenging enzyme system for each species and each treatment. In general, the SOD and CAT enzyme activities measured were higher in exposed populations than in controls, whereas APx and GPx activities showed the opposite trend. These microalgae showed significant responses of oxidative stress biomarkers at environmentally relevant concentrations for the assayed pollutants and short exposure periods, conditions that most other model organisms cannot match. Therefore microalgae present clear advantages over other species for their prospective employment in an "early warning system".

The aggregation of R-synuclein is believed to play an important role in the pathogenesis of Parkinson's disease as well as other neurodegenerative disorders ("synucleinopathies"). However, the function of R-synuclein under physiologic and pathological conditions is unknown, and the mechanism of R-synuclein aggregation is not well understood. Here we show that R-synuclein forms a tight 2:1 complex with histones and that the fibrillation rate of R-synuclein is dramatically accelerated in the presence of histones in vitro. We also describe the presence of R-synuclein and its co-localization with histones in the nuclei of nigral neurons from mice exposed to a toxic insult (i.e., injections of the herbicide paraquat). These observations indicate that translocation into the nucleus and binding with histones represent potential mechanisms underlying R-synuclein pathophysiology.

Sox2 has yet to be determined. Sox2 can act synergistically with Oct3/4 in vitro to activate Oct-Sox enhancers, which regulate the expression of pluripotent stem cellspecific genes, including Nanog, Oct3/4 and Sox2 itself. These findings suggest that Sox2 is required by ES cells for its Oct-Sox enhancer activity. Using inducible Sox2-null mouse ES cells, we show that Sox2 is dispensable for the activation of these Oct-Sox enhancers. In contrast, we demonstrate that Sox2 is necessary for regulating multiple transcription factors that affect Oct3/4 expression and that the forced expression of Oct3/4 rescues the pluripotency of Sox2-null ES cells. These results indicate that the essential function of Sox2 is to stabilize ES cells in a pluripotent state by maintaining the requisite level of Oct3/4 expression.

Supplemental Figure 1. Ribose-614 cleavage is unaffected by the addition of 10% complementary strand. Addition of equimolar amounts of the complement greatly lowers cleavage rate and plateau. (A) Cleavage profile for ribose-614 (100 nM)(triangles), or ribose-614 (115 nM) plus complementary strand (11.5 nM)(squares). (B) Cleavage profile for ribose-614 (222 nM)(triangles), or ribose-614 (200 nM) plus equimolar complementary strand (circles). Unless otherwise stated, all kinetics were performed under standard reaction conditions, namely 1M NaCl, 1 mM MgCl 2 , 50 mM HEPES, 25°C, and errors in percent cleaved are < ±2 percentage points. Supplemental Figure 2. Cleavage products do not affect ribose-614 cleavage, and only minimally alter ribose-library cleavage. Ribose-614 or ribose-library were incubated either alone (400 nM), or with the addition of the 28-nt product of 614 cleavage (400 nM), the 78-nt product of 614 cleavage (400 nM), or both (400 nM each). Data are fit to a single exponential curve. Errors in percent cleaved are < ±2 percentage points. Supplemental Figure 3. Gel-purification of ribose-614 at cleavage plateau results in additional cleaveage, indicating a fraction of 614 is folded into an inactive conformation. Ribose-614 (222 nM) was allowed to self-cleave for 140 hours, nearing cleavage plateau