Aromatic Secondary Metabolites Research Articles

Mechanistic Insights into the Antioxidant and Pro-oxidant Activities of Bromophenols from Marine Algae: A DFT Investigation.

Marine algae are a rich source of aromatic secondary metabolites, with bromophenols (BPs) receiving particular attention due to their health benefits. Despite extensive research on BPs, the understanding of their antioxidant potential, as well as their mechanisms of action at the molecular level, remains incomplete. This study utilized density functional theory (DFT) to systematically elucidate the antioxidant and pro-oxidant mechanisms of the main BP scaffolds under physiological conditions. It was found that BPs exhibit potent antioxidant capacity in both polar and lipid environments. In lipid media, the formal hydrogen transfer mechanism has been identified as the exclusive antiradical pathway. The position of bromine atoms significantly influenced the activity, particularly in scaffolds containing one hydroxyl group. However, no significant effect was observed in scaffolds with two hydroxyl groups. In water, monodeprotonated BPs showed key radical scavenging activity, with different mechanisms favored depending on the configuration of the hydroxyl groups. Additionally, BPs, particularly those bearing a catechol moiety, exhibit secondary antioxidant activity by reducing the production of hydroxyl radicals via the ascorbic acid anion pathway. These findings provide further validation of the potent antioxidant properties of BPs and shed light on their mechanism of action in physiological environments.

Aromatic secondary metabolite production from glycerol was enhanced by amino acid addition in Pichia pastoris

Aromatic secondary metabolites are widely used in various industries, including the nutraceutical, dietary supplement, and pharmaceutical industries. Their production currently relies on plant extraction. Microbe-based processes have recently attracted attention as sustainable alternatives to plant-based processes. We previously showed that the yeast Pichia pastoris (Komagataella phaffii) is an optimal host for producing aromatic secondary metabolites. Additionally, titers of resveratrol, an aromatic secondary metabolite, increased by 156 % when glycerol was used as a carbon source instead of glucose. However, the mechanisms by which glycerol resulted in higher production has remained unclear. In this study, we aimed to elucidate how P. pastoris produces higher levels of aromatic secondary metabolites from glycerol than from glucose. Titers of p-coumarate, naringenin, and resveratrol increased by 103 %, 118 %, and 157 %, respectively, in natural complex media containing glycerol compared with that in media containing glucose. However, the titers decreased in minimal synthetic medium without amino acids, indicating that P. pastoris cells used the amino acids only when glycerol was the carbon source. Fermentation with the addition of single amino acids showed that resveratrol titers from glycerol varied depending on the amino acid supplemented. In particular, addition of aspartate or tryptophan into the medium improved resveratrol titers by 146 % and 156 %, respectively. These results suggest that P. pastoris could produce high levels of aromatic secondary metabolites from glycerol with enhanced utilization of specific amino acids. This study provides a basis for achieving high-level production of aromatic secondary metabolites by P. pastoris.Key points•P. pastoris can produce high levels of aromatic metabolites from glycerol•P. pastoris cells use amino acids only when glycerol is the carbon source•Aromatic metabolite titers from glycerol increase with amino acids utilization

Whole-genome analysis of the benzoic acid-degrading bacterium Bacillus halotolerans B28 to reveal its phytoprobiotic effects

Benzoic acid is a representative allelochemical in soils affected by continuous cropping obstacles, and it is also a typical aromatic pollutant, causing a direct or indirect inhibition on crop growth. In this study, a strain B28 that was isolated from the rhizosphere of peanut by using benzoic acid as the sole carbon source and sequenced. Strain B28 contained a single circular chromosome, the complete genome size was 4,132,583 bp, the average GC was 43.89%, with 3928 predicted genes, and based on phylogenomic analyses, B28 was designated as Bacillus halotolerans. The strain B28 with outstanding abilities to biodegrade benzoic acid, enhance plant growth and control soil-borne diseases, which were the key to the phytoprobiotic functions. Genome mining revealed the potential genomic properties associated with plant growth promotion, such as aromatic xenobiotics biodegradation, IAA synthesis, biofilm formation, chemotaxis motility and secondary metabolite synthesis. The effects of strain B28 on the growth of Arachis hypogaea L. (peanut) was evaluated, and the physiological parameters of peanut such as fresh weight, dry weight, plant height and root length were significantly higher after inoculating strain B28. Overall, our present results indicate that Bacillus halotolerans B28 is a potential PGPR strain for benzoic acid bioremediation and organic agriculture application.

Multi-omics resources for targeted agronomic improvement of pigmented rice

Pigmented rice (Oryza sativa L.) is a rich source of nutrients, but pigmented lines typically have long life cycles and limited productivity. Here we generated genome assemblies of 5 pigmented rice varieties and evaluated the genetic variation among 51 pigmented rice varieties by resequencing an additional 46 varieties. Phylogenetic analyses divided the pigmented varieties into four varietal groups: Geng-japonica, Xian-indica, circum-Aus and circum-Basmati. Metabolomics and ionomics profiling revealed that black rice varieties are rich in aromatic secondary metabolites. We established a regeneration and transformation system and used CRISPR–Cas9 to knock out three flowering time repressors (Hd2, Hd4 and Hd5) in the black Indonesian rice Cempo Ireng, resulting in an early maturing variety with shorter stature. Our study thus provides a multi-omics resource for understanding and improving Asian pigmented rice.

Thymol-Nanoparticles as Effective Biocides against the Quarantine Pathogen Xylella fastidiosa.

Quarantine pathogens require the investigation of new tools for effective plant protection. In particular, research on sustainable agrochemicals is the actual challenge. Plant extracts, essential oils, and gels are natural sources of efficient biocides, such as aromatic secondary metabolites. Thymol is the major phenolic constituent of thyme and oregano essential oils, and it can inhibit many pathogenic microbes. Thymol nanoparticles were obtained through adsorption on CaCO3 nanocrystals, exploiting their carrier action. High loading efficiency and capability were reached as verified through UV and TGA measurements. We report the first study of thymol effect on Xylella fastidiosa, conducing both fluorometric assay and in vitro inhibition assay. The first test confirmed the great antibacterial effect of this compound. Finally, an in vitro test revealed an interesting synergistic action of thymol and nanocarriers, suggesting the potential application of thymol-nanoparticles as effective biocides to control Xylella fastidiosa infection.

Bacillus- and Lactobacillus-Based Dietary Synbiotics Are Associated with Shifts in the Oropharyngeal, Proximal Colonic, and Vaginal Microbiomes of Korean Native Black Pigs

In this study, we evaluated the modulatory effect of synbiotics (probiotics + prebiotics) on the oropharyngeal, proximal colonic, and vaginal microbiomes of Korean native pigs using 16S rRNA gene sequencing. We found increased abundances of an unclassified deltaproteobacterial genus in oropharyngeal communities of pigs supplemented with a Lactobacillus-based synbiotic. These pigs also had increased abundances of unclassified genera of Tremblayales and Lactobacillales in their proximal colons. In another group, pigs supplemented with a Bacillus-based synbiotic had increased Megasphaera and reduced Campylobacter within their oropharyngeal microbiota. In addition, their vaginal microbiota had increased Clostridium and Halalkalibacillus, as well as reduced Filifactor and Veillonella. We then explored changes in the predicted microbial functionality, associated with the synbiotics. Our analysis showed a reduction in the abundance of a fatty acid and lipid biosynthesis pathway among proximal colonic microbiomes of the Lactobacillus-fed pigs. In pigs supplemented with a Bacillus-based synbiotic, the analysis showed reduced pathway abundances for the biosynthesis of carbohydrates, as well as vitamins, cofactors, and carrier molecules within their oropharyngeal microbiomes. Meanwhile, their vaginal microbiomes had higher pathway abundances for aromatic compound degradation and secondary metabolite biosynthesis, but lower abundances for amino acid degradation. The results confirmed our hypothesis that dietary synbiotics modulate the microbiome, not only in the proximal colon, but also the oropharyngeal cavity and vaginal tract of these pigs.

Rapid screening of secondary aromatic metabolites in Populus trichocarpa leaves

BackgroundHigh-throughput metabolomics analytical methodology is needed for population-scale studies of bioenergy-relevant feedstocks such as poplar (Populus sp.). Here, the authors report the relative abundance of extractable aromatic metabolites in Populus trichocarpa leaves rapidly estimated using pyrolysis-molecular beam mass spectrometry (py-MBMS). Poplar leaves were analyzed in conjunction with and validated by GC/MS analysis of extracts to determine key spectral features used to build PLS models to predict the relative composition of extractable aromatic metabolites in whole poplar leaves.ResultsThe Pearson correlation coefficient for the relative abundance of extractable aromatic metabolites based on ranking between GC/MS analysis and py-MBMS analysis of the Boardman leaf set was 0.86 with R2 = 0.76 using a simplified prediction approach from select ions in MBMS spectra. Metabolites most influential to py-MBMS spectral features in the Clatskanie set included the following compounds: catechol, salicortin, salicyloyl-coumaroyl-glucoside conjugates, α-salicyloylsalicin, tremulacin, as well as other salicylates, trichocarpin, salicylic acid, and various tremuloidin conjugates. Ions in py-MBMS spectra with the highest correlation to the abundance of extractable aromatic metabolites as determined by GC/MS analysis of extracts, included m/z 68, 71, 77, 91, 94, 105, 107, 108, and 122, and were used to develop the simplified prediction approach without PLS models or a priori measurements.ConclusionsThe simplified py-MBMS method is capable of rapidly screening leaf tissue for relative abundance of extractable aromatic secondary metabolites to enable prioritization of samples in large populations requiring comprehensive metabolomics that will ultimately inform plant systems biology models and advance the development of optimized biomass feedstocks for renewable fuels and chemicals.

Plants Phenolics as Possible Pseudomonas aeruginosa Resistance Inhibitors

Pseudomonas aeruginosa virulence has for long been a serious medical, economic and social problem. It is responsible for numerous nosocomial infections like pneumonia, urinary tract infections, surgical site infections and some of community-acquired infections such as otitis, ulcerative keratitis and soft tissue infections. Its ability of adhering to various kinds of surfaces, such as hospital and surgical materials (thus: implicated in causing nosocomial infections) is one of the many reasons why P. aeruginosa is of utmost medical and economic importance. This bacterium has an extensive adaptive capability to different kinds of physical surfaces and conditions. P. aeruginosa has high capability for the formation of resistant biofilms and the regulation of efflux pumps, thus; these two contributes highly towards an elevated resistance to numerous antibiotics. Several antibiotic resistance genes are responsible for P. aeroginosa drug resistance virulence. Plant phenolics have the ability to bind to protein and non-protein domains leading to modification or inhibition protein–protein/co-factor interactions. These are a diverse group of aromatic secondary metabolites involved in plant defense. P. aeruginosa resistance genes mechanisms and evasion tactics can be affected and neutralized by ethno-plant secondary metabolites especially Phenolics, in several different ways due to the nature of its inter-molecular interactions. Ethno-plant phenolics could really provide an alternative natural remedy for the management and neutralization of P. aeruginosa Multi-drug resistance Genes.

Synergistic effect of secondary metabolites isolated from Pestalotiopsis sp. FKR-0115 in overcoming β-lactam resistance in MRSA.

Six aromatic secondary metabolites, pestalone (1), emodin (2), phomopsilactone (3), pestalachlorides B (4), C (5), and D (6), were isolated from Pestalotiopsis sp. FKR-0115, a filamentous fungus collected from white moulds growing on dead branches in Minami Daito Island. The efficacy of these secondary metabolites against methicillin-resistant Staphylococcus aureus (MRSA) with and without meropenem (β-lactam antibiotic) was evaluated using the paper disc method and broth microdilution method. The chemical structures of the isolated compounds (1-6) were characterised using spectroscopic methods, including nuclear magnetic resonance and mass spectrometry. All six isolated compounds exhibited synergistic activity with meropenem against MRSA. Among the six secondary metabolites, pestalone (1) overcame bacterial resistance in MRSA to the greatest extent.

Phytochemical and biological characterization of acetone extracts from the lichen Cladonia coniocraea and Cladonia ramulosa growing in Serbia

A comparative study of aromatic secondary metabolites and antioxidant, antimicrobial, and anticancer potential of two lichen species Cladonia coniocraea and Cladonia ramulosa is presented in this paper. HPLC-UV analysis revealed the presence of depsidone fumarprotocetraric acid and depside sekikaic acid as major aromatic metabolites in both tested species but in different amounts. The antioxidant activity was evaluated by free radical scavenging and reducing power assays. In both assays the extracts showed weak activity (IC50>1000 μg/ml, while absorbances for reducing power were from 0.0118 to 0.1675). The total content of phenol and flavonoid in extracts was examined using Folin–Ciocalteu reagent and aluminium chloride method and the obtained values were expressed as pyrocatechol equivalents, and as rutin equivalents, respectively. Further, the antimicrobial activity was estimated by determination of the minimal inhibitory concentration by the broth microdilution method against five bacterial and 10 fungal species. Tested extracts showed similar antimicrobial activity with minimum inhibitory concentration values ranging from 0.156 to 20 mg/ml. Finally, the cytotoxic activity was tested using MTT method on the human epithelial carcinoma (Hela), human lung carcinoma (A549) and human colon carcinoma (LS174) cells. The strongest cytotoxic activity with IC50 value of 185.59 μg/ml expressed extract of C. ramulosa toward Hela cells. Obtained results indicate that these lichens showed the potential for further investigation and possible biopharmaceutical application.

Essential Oils as Potential Source of Anti-dandruff Agents: A Review.

Dandruff is a frequent occurring scalp problem that causes significant discomfort to approximately 50% population at some stage of life, especially post-puberty and preadult age. In this review, we aim to summarise the recent findings regarding anti-fungal properties of herbal essential oils against pathogens involved in dandruff prognosis. A literature search of studies published between 2000 and 2020 was conducted over databases: PubMed, Google Scholar, Scopus, and Science Direct. Literature was explored using the guidelines given in Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Dandruff, characterised by clinical symptoms of dryness, pruritis, scaly, and flaky scalp, is considered as a primary manifestation of seborrheic dermatitis. Amongst various etiological and pathophysiological factors, significant role of yeasts, primarily, species of Malassezia, Candida, has been strongly correlated with dandruff, while incidences of M. furfur, M. restricta and M. globosa are high compared to others. Due to relapse of symptoms with withdrawal of conventional anti-dandruff products, patients find best alternatives in natural products. Essential oils of herbal origin such as tea tree oil, lime oil, rosemary oil, have gained global importance in dermatology. These oils are rich in aromatic secondary metabolites, especially terpenes and phenolic components that impart substantial antimicrobial properties and resisting biofilm production. On the basis of the available information, we can conclude that essential oils have huge potential to be developed as anti-dandruff products, however, further studies are warranted to establish their efficacy in dandruff cure.

Dimeric phenanthrenoids: possible biogenetic pathway and missing compounds

Secondary metabolites extracted from plants have historically been critical for drug discovery, but their isolation involves expensive and complicated procedures in terms of time and labor resources. Thus, the biogenetic pathway offers the possibility of identifying specific compounds that have not yet been isolated and predicting their isolation from specific natural sources. In plants, biphenanthrenes represent a relatively small group of aromatic secondary metabolites that are considered as important taxonomic markers with promising biological activities. To date, 38 mixed phenanthrenoid dimers have been identified, the biosynthesis of which involves the radical coupling of the two subunits, namely, a phenanthrene and a dihydrophenanthrene. For each of the compounds, it is possible to identify the single phenanthrenic and dihydrophenanthrenic units constituting the considered dimer. Based on the biogenetic pathway, it is possible to identify 19 phenanthrenes and 17 dihydrophenanthrenes, and to distinguish those already known from those not yet isolated. By comparing the results of the possible biosynthetic pathway for each compound with the data in the literature, it is possible to identify three known phenanthrenes and seven known dihydrophenanthrenes, as well as eleven new phenanthrenes and five new dihydrophenanthrenes, and to identify from which plant it is possible to isolate them. This could direct the work of researchers seeking to identify known or new molecules useful for their possible biological properties, and ultimately, to confirm the veracity of the proposed and generally accepted biosynthetic pathway.

Construction of an l-Tyrosine Chassis in Pichia pastoris Enhances Aromatic Secondary Metabolite Production from Glycerol.

Bioactive plant-based secondary metabolites such as stilbenoids, flavonoids, and benzylisoquinoline alkaloids (BIAs) are produced from l-tyrosine (l-Tyr) and have a wide variety of commercial applications. Therefore, building a microorganism with high l-Tyr productivity (l-Tyr chassis) is of immense value for large-scale production of various aromatic compounds. The aim of this study was to develop an l-Tyr chassis in the nonconventional yeast Pichia pastoris (Komagataella phaffii) to produce various aromatic secondary metabolites (resveratrol, naringenin, norcoclaurine, and reticuline). Overexpression of feedback-inhibition insensitive variants of 3-deoxy-d-arabino-heptulosonate-7-phosphate synthase (ARO4K229L) and chorismate mutase (ARO7G141S) enhanced l-Tyr titer from glycerol in P. pastoris. These engineered P. pastoris strains increased the titer of resveratrol, naringenin, and norcoclaurine by 258, 244, and 3400%, respectively, after expressing the corresponding heterologous pathways. The titer of resveratrol and naringenin further increased by 305 and 249%, resulting in yields of 1825 and 1067 mg/L, respectively, in fed-batch fermentation, which is the highest titer from glycerol reported to date. Furthermore, the resveratrol-producing strain accumulated intermediates in the shikimate pathway. l-Tyr-derived aromatic compounds were produced using crude glycerol byproducts from biodiesel fuel (BDF) production. Constructing an l-Tyr chassis is a promising strategy to increase the titer of various aromatic secondary metabolites and P. pastoris is an attractive host for high-yield production of l-Tyr-derived aromatic compounds from glycerol.

Biotransformation of Agricultural By-Products into Biovanillin through Solid-State Fermentation (SSF) and Optimization of Different Parameters Using Response Surface Methodology (RSM)

Vanillin is a flavorful and aromatic secondary metabolite found in vanilla plants. Natural vanillin, produced through processed vanilla beans accounts for scarcely 0.2% of industrial requirements. Vanillin produced via chemical methods and microbial fermentation fills the remaining gap. Among naturally available precursors for biovanillin synthesis, ferulic acid is widely used because of its structural similarity and abundant availability. Herein, various agricultural lignocellulosic by-products (sugarcane bagasse, wheat straw, rice straw, rice bran, and corn cob) were scrutinized for their ferulic acid content, and their biotransformation into biovanillin was examined by solid-state fermentation (SSF). Then, different physicochemical parameters, i.e., moisture content, pH, temperature, inoculum size, and incubation days, were optimized to achieve a high yield of biovanillin using central composite design (CCD) of response surface methodology (RSM). Among agricultural by-products tested, sugarcane bagasse produced 0.029 g/100 g of biovanillin using Enterobacter hormaechei through SSF. After optimization, the highest concentration of biovanillin (0.476 g/100 g) was achieved at a moisture content of 70%, temperature of 37.5 °C, pH 7.5, inoculum size of 4 mL and incubation time of 48 h. The F-value of 6.10 and p-value of 0.002 evidenced the ultimate significance of the model. The significance of the constructed model was supported by the 91.73% coefficient of determination (R2), indicating that the effects of moisture, pH, and temperature were significant. HPLC and FTIR confirmed the sample identification and purity (was reported to be 98.3% pure). In conclusion, sugarcane bagasse appears to be a cost-effective substrate choice for large-scale biovanillin production.

Construction of an aflatoxin aptamer sensor based on a DNA nanoprism structure.

Aflatoxin B1 (AFB1) is a group of heterocyclic aromatic hydrocarbon secondary metabolites, which are the most toxic among the known fungal toxins. Therefore, it becomes particularly important to develop sensitive, accurate, rapid and simple methods for the detection of AFB1. In this work, a method of constructing aflatoxin aptasensor with black phosphorus nano sheet loaded with gold nanoparticles as electrode modification material, Ce-metal organic framework (MOF) material as signal label and prism DNA nano structure modified electrode as recognition interface is proposed. The hybridization between prism DNA and primer probe was used to trigger rolling circle amplification (RCA) on the electrode surface, and then the complementary chain modified with Au NPs@Ce-MOF is bound to the amplification chain to provide electrochemical signals. In the range of 0.024-100 ng mL-1, the response current showed a good linear relationship with the logarithm of aflatoxin concentration, the linear equation was I = 6.4181 lg c + 11.975 with the linear correlation coefficient of 0.9973, and the detection limit was 1.48 pg mL-1 (S/N = 3).

Phytochemical screening, quantification and correlation matrix of Nigerian medicinal plant: Waltheria americana

Background: Plant’s kingdom provides new and important leads against various pharmacological targets due to the current wide spread of belief that green medicine is safe and more dependable than the costly synthetic drugs. The medicinal property of plants step from their ability to synthesize aromatic substances and secondary metabolites that are potent bioactive compounds found in medicinal plant parts that are precursors for the synthesis of useful drugs. In the present study, the leaf, stem, and root extracts of Waltheria americana were evaluated for phytochemical compositions and their correlation matrix. Methods: Quantitative and quantitative standard methods of analysis were used to evaluate the presence, amount, and the correlationships of the different phytochemicals in the leaf, root and stem of W. americana plant. Results: The quantitative phytochemicals percentage composition of W. americana varied with large ranges for alkaloids, tannins, flavonoids, but short ranges occurred of terpenes and cardiac glycosides. Alkaloids had the highest percentage composition and cardiac glycosides showed the lowest for all the plant parts. The stem seems to be the major area of phytochemical production than other parts of the plant, indicating that the stem of W. americana could serve as a major source of phytochemicals in any herbal concoction. “The correlation” of phytochemical constituents, alkaloids and tannins in the leaf were positively and significantly correlated with cardiac glycosides in the stem at 95% confidence respectiely. However, no correlation was observed of any phytochemicals in the other plant. Conclusion: These findings indicated that the production, quantification, and distribution of these phytochemicals were complimentary in nature in Waltheria americana plant, and the shoot may have played a major role in this regard

Establishment of In Vitro Cell Suspension Culture, Kinetics of Cell Growth, pH, Nutrient Uptake and Production of 2-hydroxy-4-Methoxybenzaldehyde from the Germinated Root of Decalepis hamiltonii Wight & Arn. -An Endangered Plant

Decalepis hamiltonii Wight & Arn. belongs to Asclepiadaceae family which is an ethno-pharmaceutically important monogenic plant species that is native to the Deccan peninsula forest areas of India. It is endangered due to habitat loss and over exploitation for volatile 2-hydroxy-4-methoxybenzaldehyde (HMB), which is an aromatic bioactive secondary metabolite. HMB is of great biological significance and is present in the plant’s tuberous roots. Plant cell culture is a viable alternative method for in vivo plant cultivation for secondary metabolites production. Callus induction with high biomass from the germinated root as explants for HMB production was optimised on Murashige and Skoog’s (MS) medium containing 3% (w/v) sucrose, supplemented with 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D), 1 μM α- naphthaleneacetic acid (NAA) and 10 μM 6-benzylaminopurine (BAP) in dark incubation. Cell suspension cultures were established in 250 ml shake flasks, and each flask contained 50 ml of the same induction medium. Moreover, the pH 5.8, 3% sugar concentration and 120 rpm agitation speed in dark condition were suitable for high biomass production and the specific growth rate (µ) was 0.086 /day. Extraction of HMB was done by steam condensate methods from the biomass of cell suspension culture. Qualitative and quantification analyses of HMB were performed with gas chromatography (GC) and observed that 0.92 ± 0.02 mg/ml (0.092%) HMB were synthesized in the cell suspension culture.

DNA barcoding of some medicinally important plant species of Lamiaceae family in India

Several species of the Lamiaceae family are the primary source of bioactive aromatic oils and secondary metabolites, having broader applications in the cosmetics, pharmaceuticals, food, confectionery and liquor industries. Due to the scarcity of raw materials and high costs of this family's economically vital species, its products often adulterated to cater to the market's high demand. The present study provides a DNA based approach for identifying different species of this family. Henceforth, the performance of three already proposed barcode loci (matK, trnH-psbA andtrnL) was examined for their PCR amplification and species recognition efficacy on various Lamiaceae species and cultivars using three different approaches such as pairwise genetic distance method, BLASTn and phylogenetic tree based on maximum likelihood (ML) analysis. Results illustrate that among all the DNA barcoding loci, matK locus can accurately and efficiently distinguish all the studied species followed by trnH-psbA and trnL. Present investigation may help diminish the illegal trade and events of adulteration of medicinally important plants species in genus Mentha, Ocimum and Plectranthus. This investigation will also help fulfil the scarcity of sequences of barcode loci of these species in the NCBI database. Apart from providing a molecular level reference for identifying processed herbal products, this technique also offers a convenient method for species identification and germplasm conservation of the Lamiaceae family.

Effect of Vanillic Acid in Streptozotocin Induced Diabetic Neuropathy

Diabetic neuropathy is a one of the usual complications of both type 1 and 2 diabetes mellitus. Lesion to or diseases of somatosensory system may lead to neuropathic pain which are severally painful. Apart from other etiological factors, the oxidative stress has vital role in the pathogenesis and continuation of diabetic neuropathy. Vanillic acid is the phenolic compound and aromatic secondary plant metabolite. Phenolic acids are proved to have antioxidant and neuroprotective role. So, this study was undertaken to evaluate the effects of vanillic acid on STZ induced diabetic neuropathy by assessing behavioural, biochemical, electrophysiological and histological changes. Diabetes was induced in Wistar rats by using single injection of STZ (55 mg/kg, i.p.). After confirmation of diabetes (blood glucose level >200mg/dl), animals treated with Gabapentin (300 mg/kg, p.o.) and Vanillic acid (25, 50 and 100 mg/kg, p.o) for next 4 weeks. Vanillic acid (50 and 100 mg/kg) treated rats showed significant (p<0.05) behavioral changes, decrease in blood glucose levels, significant (p<0.05) increase in reduced glutathione (RGSH) level. Treatment with vanillic acid has also reversed histopathological and electrophysiological changes. In conclusion, the present study suggested anti-hyperglycemic, antioxidant and neuroprotective effect of vanillic acid in diabetic neuropathy.

Diverse Aromatic Metabolites in the Solitary Tunicate Cnemidocarpa irene.

Fourteen aromatic metabolites (6-19) were isolated from an aqueous extract of the solitary tunicate Cnemidocarpa irene collected in Hokkaido, Japan. The structures of the metabolites were determined based on the spectroscopic interpretations, including one- and two-dimensional NMR, mass spectra, UV, and circular dichroism data. The biopterin analogue 10 modulated the behavior of mice after intracerebroventricular injection and showed a weak affinity to ionotropic glutamate receptor subtypes. Analyses of fluorescent coelomic fluid of the tunicate revealed that pterin 12 was responsible for the fluorescence of the blood cells, while β-carbolines 1 and 3 were fluorescent compounds in the serum. The metabolic profiles in adults, juveniles, larvae, and eggs of the animal differed substantially, suggesting that the metabolism of the animal, especially biosynthesis of aromatic secondary metabolites, changes over different life stages.