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Comparative evaluation of in vitro antioxidant potent of the marine actinobacteria from gulf of mannar biosphere reserve
Abstract
The present study was carried out to evaluate the in vitro antioxidant activity of actinobacteria isolated from the sediments of coral reef environment of the Gulf of Mannar Biosphere Reserve, India. Among 86 strains, five actinobacterial strains (PM15, PM16, PM17, PM18 and PM19) were tested for antioxidant potential, using standard methods. The most active strain PM17 was identified using chemotaxonomical and molecular taxonomical methods. Out of 6 different isolates, PM17 (Streptomyces sp.) showed higher antioxidant activity with an ascorbic acid equivalent of 204.16 ±0.408. Total reducing power was 81.66±0.577 μg/ml and scavenging of hydrogen peroxide and nitric oxide 66.29% and 60.30% respectively. Quantitative analysis of the scavenging assays of the strains assured the presence of antioxidant activity of the respective strains. The most active strain PM17 was taxonomically identified as a species of Streptomyces.
... Metabolites from microbes have various bioactive potentials, such as antioxidant, immunosuppressive, enzyme inhibitory, anti-inflammatory, and other therapeutic uses [71]. In the present observation, archaeal EPS has the capacity to form polyoxometalates from molybdate and convert the trivalent ferric iron into divalent ferrous iron by the oxidation process [72]. Similarly, ROS formation of the cell membrane was generated by the reaction of hydrogen peroxide with divalent ferrous, and copper ions were inhibited by the archaeal EPS [73]. ...
In the present study, halophilic archaea were isolated from a marine sediment sample. Totally, 15 isolates (AMS 1–15) were identified by molecular identification as belonging to the ten genera. Further, their extracellular polymeric substances (EPS) were extracted (3.172 g/L), and their bioactivity was determined in terms of biosurfactant, emulsification, enzymatic and non-enzymatic antioxidants, and anticancer activity. The highest amount of EPS has been produced by Halococcus sp., AMS12. It is made up of 54.28% carbohydrates, 32.91% proteins, 2.41% lipids, and other compounds. Further, EPS has 43.69 ± 1.89 U/mg of gelatinase enzyme by degrading the substrate. The potential total antioxidant activity of 103.80 ± 0.02 (ascorbic acid equivalence (AAE)), total reducing power of 86.1 ± 0.25 AAE, 1,1-diphenyl-2-picrylhydrazyl (DPPH) activity of 97.23 ± 0.21%, the hydrogen peroxide scavenging of 60.8 ± 0.21%, and nitric oxide scavenging activity of 89.37 ± 0.24% were observed at 100 μg/mL of EPS. Hence, we conclude that the archeal EPS is multifunctional and useful for developing natural polymers for industrial, food, and pharmaceutical applications.
... The gastropod egg and tissue consists of active secondary metabolites that have more antimicrobial activities because of the protecting embryos inside the capsule [5]. The antioxidant compounds are essential to trap free radicles and reduce the risk of cancer and heart disorders [6][7][8]. The large number of works has been done in other organisms, but only a few researches were done on molluscs [9]. ...
Objective: To analyse the economically important gastropods for prospective antimicrobial,
antioxidant and cytotoxic activities from the Gulf of Mannar region, southeast coast of India.
Methods: The bioactive potential of some gastropods i.e. Babylonia spirata (B. spirata),
Phalium glaucum, Tonna dolium, Hemifusus pugilinus, Xancus pyrum, Chicoreus ramosus (C.
ramosus), Harpa articularis, Ficus ficus and Babylonia zeylanica were analysed. Antimicrobial
activity was carried out against 8 human pathogenic bacteria and 3 fungal strains by well
diffusion method. Antioxidant and cytotoxic activities were analyzed by standard methods.
Results: In antibacterial and antifungal activities, methanolic extract of B. spirata significantly
showed the highest inhibition zone against Aeromonas hydrophila and Fusarium spp. (P > 0.05).
In the total antioxidant activity, the maximum activity was observed in B. spirata (510 µg/mg)
and in the 1.1-diphenyl-2-picrylhydrazyl scavenging activity, B. spirata showed the highest
percentage of inhibition (76.7%). In the case of cytotoxicity i.e. brine shrimp lethality tests
the methanolic extract of C. ramosus showed the lowest percentage of mortality and the LC50
values were found to be 523.9 µg/mL.
Conclusions: The results revealed that all the gastropods in the present study possessed
antimicrobial, antioxidant and cytotoxic effects. However, species like B. spirata and C.
ramosus exhibited potent activity and can be used for further clinical studies.
Sun overexposure is associated with the development of diseases that primarily affect the skin, which can lead to skin cancer. Among the main measures of photoprotection is the use of sunscreens. However, there is currently concern about the reported harmful effects to both humans and the environment due to several of the sunscreen ingredients available on the market. For this reason, the search for and development of new agents with photoprotective properties is required. In searching for these metabolites, researchers have turned their attention to microbial sources, especially the microbiota in unusual hostile environments. Among the diverse microorganisms available in nature, Actinobacteria and specifically Streptomyces, have been shown to be a source of metabolites with various biological activities of interest, such as antimicrobial, antitumor and immunomodulator activities. Herein, we present the results of a systematic review of the literature in which Streptomyces isolates were studied as a source of compounds with photoprotective properties. A meta-analysis of the structure-property and structure-activity relationships of those metabolites identified in the qualitative analysis phase was also carried out. These findings indicate that Streptomyces are a source of metabolites with potential applications in the development of new, safe and more eco-friendly sunscreens.
The present study is designed to investigate the preventive effects of actinobacterial
extract on colon carcinogenesis in NDEA induced mice tumor. Twenty four mice were
divided into four groups of six animals each. Animals (Group I) proceed as the control
without any treatment. Animals (Group II) were intraperitonially injected with Nnitrosodiethylamine
at three doses at an interval for ten days so as to induce colon cancer.
Animals (Group III) were orally administrated of actinobacterial strain SNI5 extract.
Animals (Group IV) were administered orally with actinobacterial extract and Nnitrosodiethylamine.
The present study demonstrated that the actinobacterial extract
effectively prevented the formation of preneoplastic foci in mice when given along with the
NDEA treatment i.e. during the inhibition phase and often the NDEA treatment until the
end of the experiment. Therefore, the present investigation demonstrated that the
actinobacterial extract SNI5 seems to be a potential, and a promising chemopreventive
agent.
The present study deals with the antioxidant and anti-inflammatory activities of Stachys lavandulifolia (S. lavandulifolia). Total phenolic content was assessed using Folin-Ciocalteu's method. The antioxidant activity was determined by measuring the scavenging activity of DPPH, ABTS, FRAP and lipid peroxidation assay. In vitro anti-inflammatory activity was evaluated using 15-lipoxygenase (15-LO) inhibitory assay. Quercetin was used as a standard drug for the study of anti-inflammatory activity. The methanolic extract of S. lavandulifolia showed highest total Phenolic content. The methanol and ethyl acetate extracts possessed strong scavenging activity in DPPH, ABTS and FRAP methods. Both ethyl acetate and methanol extracts showed Dose-Dependent protective effect against lipid peroxidation and free radical generation in liver homogenates. All extracts of S. lavandulifolia screened for anti-inflammatory LOX assay and hexane extract showed significant LOX inhibition compare to quercetin as positive control. For further investigation hexane extract was subjected to thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). One of TLC fraction showed significant LOX inhibition. The results obtained in this study confirm the traditional use of S. lavandulifolia for the treatment of painful and inflammatory conditions.
actinomycetes population ranged between 2.1 X 104 and 6.4 X 104 cfu g-1 of dry sediment. Maximum actinomycetes population was noted in rhizosphere of Avicennia marina and the minimum with Excoecaria agallocha. About 50% of the isolates showed activity against S. aureus
followed by B. subtilis, E. coli, V. cholerae, K. pheumoniae, P. vulgaris and S. typhi. Bioactive compound from one potential strain Rh1 was produced using soybean meal medium. The culture filtrate and its ethyl acetate extract showed 8-15 mm and 12-20 mm inhibition, respectively.
Based on the studied phenotypic characteristics, strain Rh1 was identified as Streptomyces fradiae (Rh1). Purification and characterization of potential actinomycetes strain Rh1 is in progress, to prove its potential further.
Unlabelled:
We have developed a new software package, Molecular Evolutionary Genetics Analysis version 2 (MEGA2), for exploring and analyzing aligned DNA or protein sequences from an evolutionary perspective. MEGA2 vastly extends the capabilities of MEGA version 1 by: (1) facilitating analyses of large datasets; (2) enabling creation and analyses of groups of sequences; (3) enabling specification of domains and genes; (4) expanding the repertoire of statistical methods for molecular evolutionary studies; and (5) adding new modules for visual representation of input data and output results on the Microsoft Windows platform.
Availability:
http://www.megasoftware.net.
Contact:
s.kumar@asu.edu
4 different actinomycete strains (A1, A2, A3 and A4) were isolated from the laterite soil samples of
Guntur region. Growth pattern and antifungal profiles of the strains were evaluated against the test
fungi such as Aspergillus flavus, Aspergillus niger, Candida albicans and Fusarium oxysporum. Based
on the cultural, morphological and physiological characteristics, the strains A1, A2 and A4 were
identified as the species of Streptomyces while the strain A3 was assigned to Nocardia. Among the 4
tested strains, Streptomyces sp. A1 showed strong antifungal activity which may provide a potent
source for antifungal metabolites
Purpose: To isolate and characterize antibiotic producing actinomycetes from soil samples in Belgaum, Karnataka, India. Methods: Crowded plate technique was used for the isolation of actinomycetes in media such as soybean - casein digest medium and actinomycetes isolation agar. The morphological and cultural characterization of one of the selected strains, designated A-4, was performed as per International Streptomycete Project (ISP). Results: Morphological and cultural studies showed that A-4 belonged to the Actinomycete genus. The morphological and cultural characteristics of the A-4 mutant showed cellular and aerial growth as well as soluble pigment formation in various ISP media. Conclusion: Findings from this investigation revealed that the selected strain, A-4, is an actinomycete.
Nitric oxide (NO) is an intra- and extracellular messenger that mediates diverse signaling pathways in target cells and is known to play an important role in many physiological processes including neuronal signaling, immune response, inflammatory response, modulation of ion channels, phagocytic defense mechanism, penile erection, and cardiovascular homeostasis and its decompensation in atherogenesis. Recent studies have also revealed a role for NO as signaling molecule in plant, as it activates various defense genes and acts as developmental regulator. In plants, NO can also be produced by nitrate reductase. NO can operate through posttranslational modification of proteins (nitrosylation). NO is also a causative agent in various pathophysiological abnormalities. One of the very important systems, the cardiovascular system, is affected by NO production, as this bioactive molecule is involved in the regulation of cardiovascular motor tone, modulation of myocardial contractivity, control of cell proliferation, and inhibition of platelet activation, aggregation, and adhesion. The prime source of NO in the cardiovascular system is endothelial NO synthase, which is tightly regulated with respect to activity and localization. The inhibition of chronic NO synthesis leads to neurogenic and arterial hypertensions, which later contribute to development of myocardial fibrosis. Overall, the modulation of NO synthesis is associated with hypertension. This review briefly describes the physiology of NO, its synthesis, catabolism, and targeting, the mechanism of NO action, and the pharmacological role of NO with special reference to its essential role in hypertension.
Streptomyces sp. MNK7 was isolated from Natore, Bangladesh. Morphological, physiological and biochemical studies strongly suggested that the isolate belonged to Streptomyces. Attempts were made to optimize the culture conditions for the production of antimicrobial metabolite by this strain. Antimicrobial metabolite production was started after 3 days of incubation and maximum level was obtained after 10 days and thereafter gradually decreased. The optimum temperature and pH for antimicrobial metabolite production was 35oC and 5 respectively. Inositol and L-Asparagine as carbon and nitrogen sources was proved to be the best for production of bioactive metabolite. The extract of metabolite was obtained by solvent extraction method using ethyl acetate as the solvent. The ethyl acetate extract exhibited reasonable antibacterial activities against a series of Gram positive and Gram negative bacteria. The minimum inhibitory concentrations (MICs) of crude extract were found to be in the range of 32-64 mg/ml against seven pathogenic bacteria. The extract also assessed for preliminary cytotoxicity and the LC50 values were found to be 7.58 μg/ml.
A new method called the neighbor-joining method is proposed for reconstructing phylogenetic trees from evolutionary distance data. The principle of this method is to find pairs of operational taxonomic units (OTUs [= neighbors]) that minimize the total branch length at each stage of clustering of OTUs starting with a starlike tree. The branch lengths as well as the topology of a parsimonious tree can quickly be obtained by using this method. Using computer simulation, we studied the efficiency of this method in obtaining the correct unrooted tree in comparison with that of five other tree-making methods: the unweighted pair group method of analysis, Farris's method, Sattath and Tversky's method, Li's method, and Tateno et al.'s modified Farris method. The new, neighbor-joining method and Sattath and Tversky's method are shown to be generally better than the other methods.
A total of 160 isolates of marine actinomycetes were isolated from the sediment samples drawn from mangroves, estuary, sand dune, and industrially polluted coast. Of these, mangrove sediments were rich sources of marine actinomycetes. Each isolate was tested against four phytopathogenic fungi, viz. Rhizoctonia solani, Pyricularia oryzae, Helminthosporium oryzae (causing sheath blight, blast and leaf spot diseases of rice) and Colletotrichum falcatum (causing red rot disease of sugar cane). About 51% of isolates were found effective against H. oryzae and P. oryzae, 31% against R. solani, and 12.5% against C. falcatum. Of 160 isolates, 10 showed a potent activity against all the fungi tested. These isolates appeared to produce high antifungal compounds at 120 hrs of incubation period of production medium culture. Glucose and soybean meal were the best carbon and nitrogen sources, respectively and 17.5 ppt was the best salinity level for maximum antibiotic production. Cylinder plate method was found better for antifungal assay than the disc diffusion method. Based on the morphological and culture characteristics, the potent strains were identified as the species belonged to the genus Streptomyces. These strains may prove to be the potent source for isolation of agrobased fungicides.
Four successive extracts of the whole plant of Enicostemma axillare (E. axillare), were examined for in vitro antioxidant activity using nine different methods. In the 2,2 -azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid) diammonium salt (ABTS) method, all the four extracts of E. axillare showed potent antioxidant activity with IC 50 values ranging from 13.26 to 24.36 µg/ml. The chloroform extract has shown potent antioxidant activity in H 2 O 2 , nitric oxide, and hydroxyl radical using the deoxyribose and lipid peroxidation methods, with IC 50 values of 16.99 ± 0.38, 60.66 ± 0.30, 25.06 ± 0.12, and 94.66 ± 2.40 µg/ml, respectively. Potent activity was also observed for the petroleum ether extract with the deoxyribose, p-nitroso dimethyl aniline (p-NDA), and H 2 O 2 methods and for the ethyl acetate extract with the H 2 O 2 and nitric oxide methods. All extracts showed moderate total antioxidant capacity using the phosphomolybdenum method. The activity was not correlated with the total phenol content of the extracts.
In the late 1950's free radicals and antioxidants were almost unheard of in the clinical and biological sciences but chemists had known about them for years in the context of radiation, polymer and combustion technology. Daniel Gilbert, Rebeca Gerschman and their colleagues related the toxic effects of elevated oxygen levels on aerobes to those of ionizing radiation, and proposed that oxygen toxicity is due to free radical formation, in a pioneering paper in 1956. Biochemistry owes much of its early expansion to the development and application of chromatographic and electrophoretic techniques, especially as applied to the study of proteins. Thus, superoxide dismutase (SOD) enzymes (MnSOD, CuZnSOD, FeSOD) were quickly identified. By the 1980's Molecular Biology had evolved from within biochemistry and microbiology to become a dominant new discipline, with DNA sequencing, recombinant DNA technology, cloning, and the development of PCR representing milestones in its advance. As a biological tool to explore reaction mechanisms, SOD was a unique and valuable asset. Its ability to inhibit radical reactions leading to oxidative damage in vitro often turned out to be due to its ability to prevent reduction of iron ions by superoxide. Nitric oxide (NO·) provided the next clue as to how SOD might be playing a critical biological role. Although NO· is sluggish in its reactions with most biomolecules it is astoundingly reactive with free radicals, including superoxide. Overall, this high reactivity of NO· with radicals may be beneficial in vivo, e.g. by scavenging peroxyl radicals and inhibiting lipid peroxidation. If reactive oxygen species are intimately involved with the redox regulation of cell functions, as seems likely from current evidence, it may be easier to understand why attempts to change antioxidant balance in aging experiments have failed. The cell will adapt to maintain its redox balance. Indeed, transgenic animals over-expressing antioxidants show some abnormalities of function. There must therefore be a highly complex interrelationship between dietary, constitutive, and inducible antioxidants within the body, under genetic control. The challenge for the new century is to be able to understand these relationships, and how to manipulate them to our advantage to prevent and treat disease.
The antioxidant activity and free-radical and active oxygen-scavenging activity of burdock extracts were investigated. Of
the solvents used for extraction, water yielded the greatest amount of extract that exhibited the strongest antioxidant activity.
Water extracts of burdock (WEB) and hot water extracts of burdock (HWEB) exhibited comparable and marked activity on inhibition
of linoleic acid peroxidation, indicating that heat treatment did not alter the antioxidant activity of WEB. WEB and HWEB
produced significantly lower (P<0.05) malondialdehyde (MDA) in both linoleic acid and liposome model systems than did the control. Moreover, mixtures of
tocopherol (Toc), WEB, and HWEB exhibited a remarkable synergistic antioxidant effect in a liposome system; WEB and HWEB thus
potentiated the action of Toc. Furthermore, WEB and HWEB displayed a marked inhibitory effect on lipid peroxidation of rat
liver homogenate in vitro. WEB and HWEB exhibited an 80% scavenging effect on α,α-diphenyl-β-picrylhydrazyl radical and marked reducing power, indicating
that WEB and HWEB act as primary antioxidants. Both extracts at a dose of 1.0 mg exhibited a 60.4–65.0% scavenging effect
on superoxide and an 80.5% scavenging effect on hydrogen peroxide. They also showed a marked scavenging effect on the hydroxyl
radical. These results revealed that WEB and HWEB are also active as oxygen scavengers and as secondary antioxidants. Based
on these results, termination of free-radical reactions and quenching of reactive oxygen species in burdock extracts are suggested
to be, in part, responsible for the antioxidant activity of burdock extracts.
This paper aims to investigate the effect of H2O2 and paraquat on the activities of superoxide dismutase (SOD) and catalase (CAT), and membrane lipid peroxidation (LPO) levels in newly isolated Streptomyces sp. M3004. SOD activities of Streptomyces sp. M3004, grown in 10 mM and 30 mM H2O2, were significantly lower than the control cultures. On the other hand, as an antioxidant enzyme, CAT activity in both H2O2 treatment conditions increased significantly compared with the control. These activity values in 10 mM and 30 mM H2O2 treatment on the 48th hour of incubation were 3.8- and 6.6-fold higher than the control, respectively. SOD activity decreased significantly with respect to paraquat concentration, which was added at the start of the incubation. CAT activities increased significantly in 1.0 mM and 3.0 mM paraquat treatments compared to control. As an indicative marker of membrane damage, LPO levels of the novel isolate Streptomyces sp. M3004 treated with H2O2, and paraquat stress conditions were significantly higher than the control. Nevertheless, compared with the 30 mM H2O2 in both treatment conditions, LPO levels in 10 mM H2O2 were significantly higher. The decreases in SOD activities in paraquat and H2O2 treatment conditions resulted in the increases in the LPO levels although it increases in CAT activities.
Streptopyrrolidine, a benzyl pyrrolidine derivative, was isolated as an angiogenesis inhibitor from the fermentation broth of a marine Streptomyces sp. isolated from the deep sea sediment. Its structure was elucidated by extensive 2D NMR and mass spectroscopic analyses. Streptopyrrolidine exhibited significant anti-angiogenesis activity.
Cladoniamides A-G (3- 9) have been isolated from cultures of Streptomyces uncialis, and their structures have been elucidated by a combination of spectroscopic analysis and an X-ray diffraction analysis of cladoniamide A (3). The cladoniamides have unprecedented rearranged and degraded alkaloid skeletons with putative biogenetic origins from indolocarbazole precursors. Cladoniamide G (9) is cytotoxic to MCF-7 cells in vitro at 10 microg/mL.
Sometimes, we are met with unprecedented challenges and have to rely on our instincts for our decision of how to act. More often than not, this leads to improved results, but occasionally, we worsen our situation by our own attempts to improve it. For example, when sinking in quicksand, it would be advantageous to move very carefully; however, we tend to panic and struggle wildly instead, thus sinking further and actively worsening our situation. Bacteria also face life-threatening situations, for instance, when they are exposed to drugs that threaten their survival. Presumably, billions of years of evolution have “taught” organisms how to respond to such insults to ensure their own survival or at least that of their relatives. Hence, when exposed to attacks, single-celled organisms typically defy their fate by eliciting evolved protective responses. But do they—like humans—sometimes “overreact” and respond in a way that ultimately leads to their own death? In this issue, Graham Walker, Jim Collins, and their colleagues (Davies et al., 2009) show that the bacterium Escherichia coli responds to the drug hydroxyurea (HU) in ways that successfully ensure its survival for several hours but promote cell death at longer times.
A marine actinobacterium isolated from the Bay of Bengal, India and previously found to be producing an antimicrobial and cytotoxic terpenoid was further investigated for antimicrobial metabolites. The bacterium was preliminarily identified as a new species of the genus Streptomyces (strain MS1/7). The cell-free culture broth was extracted with n-butanol and purified using silica gel column chromatography and high-performance liquid chromatography. Molecular characterization was done using ESI mass, IR and 1H and 13C NMR spectrometry. 2-Allyloxyphenol (MW 150; C9H10O2), a synthetic drug and chemical intermediate, was obtained as a natural product for the first time. Serendipitous natural occurrence provided new insights into the synthetic molecule. 2-Allyloxyphenol was found to be inhibitory to 21 bacteria and three fungi in the minimum range 0.2-1.75 mg mL(-1) determined by agar dilution method. 2-Allyoxyphenol possesses strong antioxidant property (IC(50) 22 microg mL(-1), measured by 1, 1-diphenyl-2-picryl hydrazyl scavenging activity). Hydroxyl and allyloxy groups in 2-allyloxyphenol were responsible for antimicrobial and antioxidant activities. 2-Allyloxyphenol has marked resemblance to smoky aroma and is two to three times more active as an antimicrobial than some commercial smoke-flavour compounds. Absence of hemolytic toxicity, potential carcinogenicity, cytotoxicity and reports of toxic reactions in literature suggest possible application of 2-allyloxyphenol as a food preservative and an oral disinfectant.
Reactive oxygen species are constantly formed in the human body and removed by antioxidant defenses. An antioxidant is a substance that, when present at low concentrations compared to that of an oxidizable substrate, significantly delays or prevents oxidation of that substrate. Antioxidants can act by scavenging biologically important reactive oxygen species (O2-., H2O2.OH, HOCl, ferryl, peroxyl, and alkyl), by preventing their formation, or by repairing the damage that they do. One problem with scavenging-type antioxidants is that secondary radicals derived from them can often themselves do biologic damage. These various principles will be illustrated by considering several thiol compounds.
A new method called the neighbor-joining method is proposed for reconstructing phylogenetic trees from evolutionary distance data. The principle of this method is to find pairs of operational taxonomic units (OTUs [= neighbors]) that minimize the total branch length at each stage of clustering of OTUs starting with a starlike tree. The branch lengths as well as the topology of a parsimonious tree can quickly be obtained by using this method. Using computer simulation, we studied the efficiency of this method in obtaining the correct unrooted tree in comparison with that of five other tree-making methods: the unweighted pair group method of analysis, Farris's method, Sattath and Tversky's method, Li's method, and Tateno et al.'s modified Farris method. The new, neighbor-joining method and Sattath and Tversky's method are shown to be generally better than the other methods.
The actinomycetes, although not all the Actinobacteria, are easy to isolate from the marine environment. However, their ecological role in the marine ecosystem is largely neglected and various assumptions meant there was little incentive to isolate strains for search and discovery of new drugs. However, the marine environment has become a prime resource in search and discovery for novel natural products and biological diversity, and marine actinomycetes turn out to be important contributors. Similarly, striking advances have been made in marine microbial ecology using molecular techniques and metagenomics, and actinobacteria emerge as an often significant, sometimes even dominant, environmental clade. Both approaches - cultivation methods and molecular techniques - are leading to new insights into marine actinobacterial biodiversity and biogeography. Very different views of actinobacterial diversity emerge from these, however, and the true extent and biogeography of this are still not clear. These are important for developing natural product search and discovery strategies, and biogeography is a hot topic for microbial ecologists.
Evaluation of invitro antioxidant activity of (alkaloids) a marine actinobacterium isolated from Nancowry Island Andaman and Nicobar Islands
- K Kamala
Kamala K (2011) Evaluation of invitro antioxidant activity of
(alkaloids) a marine actinobacterium isolated from Nancowry
Island Andaman and Nicobar Islands, India. M.Phil thesis, Annamalai University