Project description:The light and scanning electron microscopic observations were carried out for anatomical features of leaf, pollens and powder.Microscopic studies provide useful information for identification and authentication of adulteration in A. maritima. Nutritional analysis of A. maritima revealed that life fundamental macromolecules such as carbohydrates (49.63 %) crude proteins (13.17 %) and crude fibers (21.06 %) were present in sufficient quantity while crude fats (4.11 %) reported in low quantity. The life essential elements such as Mg (9.472 ± 0.011), Ca (4.152 ± 0.135) and Fe (4.112 ± 0.002) were found in high concentration while heavy metals reported under the safety threshold of WHO. These observations favored A. maritima an alternative of food.Appreciable quantity of phenolics (17.64 ± 0.574) and flavonoids (7.67 ± 0.069) were found while qualitatively active phytochemicals were reported. The FTIR characterization of A. maritima crude powder revealed chromatogram in 3328.61 to 408.68 frequency range and 24 characteristic peaks on the basis of which different compounds of biological importance were classified. HPLC-UV technique quantifiedand identified six phenolic compounds morin,epigallocatechin gallate, catechin hydrate,ellagic acid, pyrogallol andrutin. Identification of compounds through GC-MS chromatogram revealed the presence of 46 compounds in methanolic fraction however 17 compounds of biological importance were selected. In-vitro biological evaluation of A. maritima for antioxidant, antimicrobial, antidiabetic (12.61 ± 0.113 %) and cytotoxic activities (LC50 = 20 μg/ml) suggested that methanolic fractions exhibited the highest activity as compared to chloroform and ethyl acetate fractions. The MIC values of 10 or 15 mg/ml were recorded for most of the fungal pathogens. Antibacterial activity revealed 3.75 mg/ml of MIC values against B. subtilis and 1.87 mg/ml against S. aureus, E. coli and P. aeruginosa. In-vivo biological evaluation revealed thatmaximum inhibition was observed for crude extract at 250 mg/kg body weight. The mechanism underlined in-vivo analgesic responses was carried out which revealed that naloxone (morphine and tramadol antagonist) showed no prominent effect while Glibenclamide pretreatment minutely modified the analgesic action. These observations clearly indicted the absence of opiod receptors and involvement of ATP sensitive potassium channels.
Project description:Artemisinin, a sesquiterpene lactone exhibiting effective antimalarial activity, is produced by only Artemisia annua plant. A key step in artemisinin biosynthesis is the cyclization of farnesyl pyrophosphate (FPP) to amorpha-4,11-diene catalyzed by amorpha-4,11-diene synthase (AaADS). Intriguingly, several non-artemisinin-producing Artemisia plants also express genes highly homologous to AaADS. Our previous functional analysis of these homologous enzymes revealed that they catalyzed the synthesis of rare natural sesquiterpenoids. In this study, we analyzed the function of another putative sesquiterpene synthase highly homologous to AaADS from A. maritima. Unlike AaADS, in vivo enzymatic assay showed that this enzyme cyclized FPP to 4-amorphen-11-ol, a precursor of several gastroprotective agents. The discovery of 4-amorphen-11-ol synthase (AmAOS) and the successful de novo production of 4-amorphen-11-ol in engineered yeast demonstrated herein provides insights into the methods used to enhance its production for future application.
Project description:This work explored the biotechnological potential of the medicinal halophyte Artemisia campestris subsp. maritima (dune wormwood) as a source of health promoting commodities. For that purpose, infusions, decoctions and tinctures were prepared from roots and aerial-organs and evaluated for in vitro antioxidant, anti-diabetic and tyrosinase-inhibitory potential, and also for polyphenolic and mineral contents and toxicity. The dune wormwood extracts had high polyphenolic content and several phenolics were identified by ultra-high performance liquid chromatography-photodiode array-mass-spectrometry (UHPLC-PDA-MS). The main compounds were quinic, chlorogenic and caffeic acids, coumarin sulfates and dicaffeoylquinic acids; several of the identified phytoconstituents are here firstly reported in this A. campestris subspecies. Results obtained with this plant's extracts point to nutritional applications as mineral supplementary source, safe for human consumption, as suggested by the moderate to low toxicity of the extracts towards mammalian cell lines. The dune wormwood extracts had in general high antioxidant activity and also the capacity to inhibit α-glucosidase and tyrosinase. In summary, dune wormwood extracts are a significant source of polyphenolic and mineral constituents, antioxidants and α-glucosidase and tyrosinase inhibitors, and thus, relevant for different commercial segments like the pharmaceutical, cosmetic and/or food industries.
Project description:Pulse beetle is the major pests of pulses that cause significant loss to grains leads to unfit for consumption and marketing. Indiscriminate use of synthetic pesticides for the control of pulse beetle (Callosobruchus chinensis and Callosobruchus maculatus) led to insect resistance, pesticide residues on grains which affect consumer's health and environment. Essential oils (EOs) are good alternatives to synthetics due to their safety to the environment and consumers' health. The main objective of the present study was to explore the chemical composition, fumigant, repellency, ovipositional deterrence, persistence, and detoxification enzyme inhibition of Artemisia maritima essential oil against pulse beetle. Results showed that primary components of the EO were 1,8-Cineole and bornyl acetate. EO showed promising fumigant toxicity to C. chinensis and C. maculatus (LC50 = 1.17 and 0.56 mg/L, respectively) after 48 h. In the repellent assay, EO at 8 mg/L showed 92-96% repellence after 1 h. In ovipositional deterrence assay, EO showed more ovipositional deterrence against C. chinensis (OD50 = 3.30 mg/L) than C. maculatus (OD50 = 4.01 mg/L). Higher concentrations of oil (8 and 6 mg/L) in C. maculatus showed significant inhibition of the glutathione-S-transferase enzyme (7.14 and 5.61 n mol/min/mL, respectively).
Project description:We sought to determine the transcriptomic impacts of artemisinin, Artemisia annua extract, and Artemisia afra extract on M. tuberculosis. Log phase cultures were treated with lethal doses for four hours or with inhibitory or sub-inhibitory doses for 24 hours. RNA was collected from untreated controls at the same timepoint.
Project description:DHDPS (dihydrodipicolinate synthase) catalyses the branch point in lysine biosynthesis in bacteria and plants and is feedback inhibited by lysine. DHDPS from the thermophilic bacterium Thermotoga maritima shows a high level of heat and chemical stability. When incubated at 90 degrees C or in 8 M urea, the enzyme showed little or no loss of activity, unlike the Escherichia coli enzyme. The active site is very similar to that of the E. coli enzyme, and at mesophilic temperatures the two enzymes have similar kinetic constants. Like other forms of the enzyme, T. maritima DHDPS is a tetramer in solution, with a sedimentation coefficient of 7.2 S and molar mass of 133 kDa. However, the residues involved in the interface between different subunits in the tetramer differ from those of E. coli and include two cysteine residues poised to form a disulfide bond. Thus the increased heat and chemical stability of the T. maritima DHDPS enzyme is, at least in part, explained by an increased number of inter-subunit contacts. Unlike the plant or E. coli enzyme, the thermophilic DHDPS enzyme is not inhibited by (S)-lysine, suggesting that feedback control of the lysine biosynthetic pathway evolved later in the bacterial lineage.
Project description:Ethnopharmacological relevanceEmergence of drug-resistant and multidrug-resistant Mycobacterium tuberculosis (Mtb) strains is a major barrier to tuberculosis (TB) eradication, as it leads to longer treatment regimens and in many cases treatment failure. Thus, there is an urgent need to explore new TB drugs and combinations, in order to shorten TB treatment and improve outcomes. Here, we evaluated the potential of two Asian and African traditional medicinal plants, Artemisia annua, a natural source of artemisinin (AN), and Artemisia afra, as sources of novel antitubercular agents.Aim of the studyOur goal was to measure the activity of A. annua and A. afra extracts against Mtb as potential natural and inexpensive therapies for TB treatment, or as sources of compounds that could be further developed into effective treatments.Materials and methodsThe minimum inhibitory concentrations (MICs) of A. annua and A. afra dichloromethane extracts were determined, and concentrations above the MICs were used to evaluate their ability to kill Mtb and Mycobacterium abscessus in vitro.ResultsPrevious studies showed that A. annua and A. afra inhibit Mtb growth. Here, we show for the first time that Artemisia extracts have a strong bactericidal activity against Mtb. The killing effect of A. annua was much stronger than equivalent concentrations of pure AN, suggesting that A. annua extracts kill Mtb through a combination of AN and additional compounds. A. afra, which produces very little AN, displayed bactericidal activity against Mtb that was substantial but weaker than that of A. annua. In addition, we measured the activity of Artemisia extracts against Mycobacterium abscessus. Interestingly, we observed that while A. annua is not bactericidal, it inhibits growth of M. abscessus, highlighting the potential of this plant in combinatory therapies to treat M. abscessus infections.ConclusionOur results indicate that Artemisia extracts have an enormous potential for treatment of TB and M. abscessus infections, and that these plants contain bactericidal compounds in addition to AN. Combination of extracts with existing antibiotics may not only improve treatment outcomes but also reduce the emergence of resistance to other drugs.