Secondary Metabolite Profiles Research Articles

Metabolic profiling provides insights into the accumulation patterns of flavonoids and phenolic acids in different parts of Lactuca indica L.

Lactuca indica L. contains high amounts of flavonoids and phenolic acids. However, there is limited information on the composition of these compounds in different parts of the plant. The present study analyzed the secondary metabolite profiles of the stem, leaf, flower, and seed of Lactuca indicaL.cv. Mengzao (LIM) using a widely targeted metabolomic approach. A total of 576 secondary metabolites were identified, including 218, 267, 232, 286, 302, and 308 differentially accumulated metabolites (DAMs) in the stem_vs_leaf, stem_vs_flower, stem_vs_seed, leaf_vs_flower, leaf_vs_seed, and flower_vs_seed comparisons. In particular, considerable differences were detected in the flavonoids and phenolic acids, five flavonoids, five phenolic acids, one triterpenoid and one alkaloid being differentially accumulated in the four parts. Compared to the stem and flower, the leaf and seed had higher total flavonoid content and total phenolic content. Thses findings provide comprehensive insights into utilizing different parts of LIM in developing functional food products.

Tissue-specific and novel secondary metabolites identified by SPME/GC-MS in Artemisia annua calli cultured under different wavelength

The controlled environment in the in vitro conditions allow for a stable and high-quality production of metabolites. Also, the use of different tissues, under in vitro conditions, can produce a profile of secondary metabolites different from those produced under conventional systems. The present study aimed to develop a protocol for in vitro calli induction and proliferation of Artemisia annua, and to compare the secondary metabolite profile of in vitro calli, in vitro plantlets, and plants cultivated ex vitro. The effects of different light wavelengths on the production of secondary metabolites were also evaluated. The presence of phytoregulators 6-Benzylaminopurine (BAP) and Naphthalene Acetic Acid (NAA) promoted the induction and proliferation of calli, with an increase in diameter and fresh weight of the calli. SPME/GC-MS analysis showed differences in the profile of secondary metabolites produced by different A. annua cultivation systems and light wavelengths. White light sources (cold fluorescent) and red light (LEDs) resulted in a greater diversity of metabolites produced by the calli. In total, 25 metabolites were detected exclusively in calli of A. annua, four of which are reported for the first time in the species: menthyl acetate, geranyl acetate, 4-methoxy benzaldehyde, and alpha-santalene. Of these, six metabolites were uniquely identified in calli cultured under red LED, demonstrating calli response specificity. The results demonstrate the potential of in vitro culture of A. annua calli in the production of metabolites different from those obtained in different tissues, such as in vitro plantlets and plants grown in greenhouse.

Phytochemical Screening and Profiling of Secondary Metabolites of Annona Muricata Bark

Screening of phytochemicals is a precious stair in the detection of bioactive principles present in medicinal plants and may lead to novel drug discovery). In present study aimed to investigate the preliminary phytochemical screening, fluorescence, and spectroscopic characterization in Annona muricata bark. The qualitative analysis of aqueous, hexane, ethanol, hydro-ethanolic and methanol extracts of Annona muricata bark were investigated. Among the various extracts, the hydro-ethanolic extract of Annona muricata bark contains a higher concentration of phytochemicals than other extracts and is used for subsequent studies. Quantitative analysis revealed that the Annona muricata bark has contain significant amount of phenol, flavonoids, saponin, tannin and alkaloids were present. Histochemical analysis further confirmed the presence of phytochemicals in Annona muricata bark. UV-VIS spectral analysis we can confirm that the presence of tannins and flavonoids. FTIR analysis had confirmed the presence of alcohol, phenol, aromatic, carboxylic acid, and aliphatic amines. Results of the study concluded that rich source of phytochemicals in Annona muricata bark is responsible for their therapeutic effects. So, it is recommended as a plant of phytopharmaceutical importance and further studies are needed with these plants to evaluate their pharmacological potentials of the bioactive compounds responsible for their bio-activities and other medicinal values.

Development of an adhesive tablet for the delivery of Diospyros villosa root for the treatment of oral cavity diseases

The Diospyros villosa root extract (DVR) has the potential to treat oral cavity diseases (DOC), as confirmed by its frequent use as a toothbrush among Mozambicans. In the present work, a tablet with adhesive properties was developed with properties that have the potential to overcome the expected difficulties in delivering the drug into the oral cavity. The chemical profile of the extract marker secondary metabolites was established by TLC and LC-UV/DAD, and the quantification of its main classes was performed by UV and IR spectrophotometries. The size of the particles of the extract was determined by laser diffractometry. The tablets manufactured were evaluated to confirm the extract chemical stability based on the major marker secondary metabolite profile, throughout processing (differential scanning calorimetry, DSC and Fourier transform infrared spectroscopy, FTIR) and their performance based on adhesion forces (i.e., force required to remove a tablet from a flat surface) and for their ability to release the main marker secondary metabolites (dissolution test). The study has shown that the use of colloidal silica in the preparation of the extract delivered a powder containing particles with improved flow and by adding an adhesive polyacrylic acid derivative to the composite extract particles it was possible to obtain a blend enabling the manufacture of adhesive tablets by direct compression. Overall, the study demonstrated the ability to produce DVR-containing adhesive tablets for buccal use against DOC.

The Metabolite Profiling of Aspergillus fumigatus KMM4631 and Its Co-Cultures with Other Marine Fungi.

An Aspergillus fumigatus KMM 4631 strain was previously isolated from a Pacific soft coral Sinularia sp. sample and was found to be a source of a number of bioactive secondary metabolites. The aims of this work are the confirmation of this strain' identification based on ITS, BenA, CaM, and RPB2 regions/gene sequences and the investigation of secondary metabolite profiles of Aspergillus fumigatus KMM 4631 culture and its co-cultures with Penicillium hispanicum KMM 4689, Amphichorda sp. KMM 4639, Penicillium sp. KMM 4672, and Asteromyces cruciatus KMM 4696 from the Collection of Marine Microorganisms (PIBOC FEB RAS, Vladivostok, Russia). Moreover, the DPPH-radical scavenging activity, urease inhibition, and cytotoxicity of joint fungal cultures' extracts on HepG2 cells were tested. The detailed UPLC MS qTOF investigation resulted in the identification and annotation of indolediketopiperazine, quinazoline, and tryptoquivaline-related alkaloids as well as a number of polyketides (totally 20 compounds) in the extract of Aspergillus fumigatus KMM 4631. The metabolite profiles of the co-cultures of A. fumigatus with Penicillium hispanicum, Penicillium sp., and Amphichorda sp. were similar to those of Penicillium hispanicum, Penicillium sp., and Amphichorda sp. monocultures. The metabolite profile of the co-culture of A. fumigatus with Asteromyces cruciatus differed from that of each monoculture and may be more promising for the isolation of new compounds.

Phytochemical characterization of Typha domingensis and the assessment of therapeutic potential using in vitro and in vivo biological activities and in silico studies.

Typha domingensis, a medicinal plant with significant traditional importance for curing various human diseases, has potentially bioactive compounds but was less explored previously. Therefore, this study aims to investigate the therapeutic potential of T. domingensis by evaluating the phytochemical profile through high-performance liquid chromatography (HPLC) techniques and its biological activities (in vitro and in vivo) from the methanolic extract derived from the entire plant (TDME). The secondary metabolite profile of TDME regulated by reverse phase ultra-high-performance liquid chromatography-mass spectrometry (RP-UHPLC-MS) revealed some bioactive compounds by -ve and +ve modes of ionization. The HPLC quantification study showed the precise quantity of polyphenols (p-coumaric acid, 207.47; gallic acid, 96.25; and kaempferol, 95.78μg/g extract). The enzyme inhibition assays revealed the IC50 of TDME as 44.75 ± 0.51, 52.71 ± 0.01, and 67.19 ± 0.68µgmL-1, which were significant compared to their respective standards (indomethacin, 18.03 ± 0.12; quercetin, 4.11 ± 0.01; and thiourea, 8.97 ± 0.11) for lipoxygenase, α-glucosidase, and urease, respectively. Safety was assessed by in vitro hemolysis (4.25% ± 0.16% compared to triton × 100, 93.51% ± 0.36%), which was further confirmed (up to 10g/kg) by an in vivo model of rats. TDME demonstrated significant (p < 0.05) potential in analgesic activity by hot plate and tail immersion tests and anti-inflammatory activity by the carrageenan-induced hind paw edema model. Pain latency decreased significantly, and the anti-inflammatory effect increased in a dose-dependent way. Additionally, in silico molecular docking revealed that 1,3,4,5-tetracaffeoylquinic acid and formononetin 7-O-glucoside-6″-O-malonate possibly contribute to enzyme inhibitory activities due to their higher binding affinities compared to standard inhibitors. An in silico absorption, distribution, metabolism, excretion, and toxicological study also predicted the pharmacokinetics and safety of the chosen compounds identified from TDME. To sum up, it was shown that TDME contains bioactive chemicals and has strong biological activities. The current investigations on T. domingensis could be extended to explore its potential applications in nutraceutical industries and encourage the isolation of novel molecules with anti-inflammatory and analgesic effects.

Untargeted metabolomic analyses support the main phylogenetic groups of the common plant-associated Alternaria fungi isolated from grapevine (Vitis vinifera)

Alternaria, a cosmopolitan fungal genus is a dominant member of the grapevine (Vitis vinifera) microbiome. Several Alternaria species are known to produce a variety of secondary metabolites, which are particularly relevant to plant protection and food safety in field crops. According to previous findings, the majority of Alternaria species inhabiting grapevine belong to Alternaria sect. Alternaria. However, the phylogenetic diversity and secondary metabolite production of the distinct Alternaria species has remained unclear. In this study, our aim was to examine the genetic and metabolic diversity of endophytic Alternaria isolates associated with the above-ground tissues of the grapevine. Altogether, 270 Alternaria isolates were collected from asymptomatic leaves and grape clusters of different grapevine varieties in the Eger wine region of Hungary. After analyses of the nuclear ribosomal DNA internal transcribed spacer (ITS) and RNA polymerase second largest subunit (rpb2) sequences, 170 isolates were chosen for further analyses. Sequences of the Alternaria major allergen gene (Alt a 1), endopolygalacturonase (endoPG), OPA10-2, and KOG1058 were also included in the phylogenetic analyses. Identification of secondary metabolites and metabolite profiling of the isolates were performed using high-performance liquid chromatography (HPLC)–high-resolution tandem mass spectrometry (HR-MS/MS). The multilocus phylogeny results revealed two distinct groups in grapevine, namely A. alternata and the A. arborescens species complex (AASC). Eight main metabolites were identified in all collected Alternaria isolates, regardless of their affiliation to the species and lineages. Multivariate analyses of untargeted metabolites found no clear separations; however, a partial least squares-discriminant analysis model was able to successfully discriminate between the metabolic datasets from isolates belonging to the AASC and A. alternata. By conducting univariate analysis based on the discriminant ability of the metabolites, we also identified several features exhibiting large and significant variation between A. alternata and the AASC. The separation of these groups may suggest functional differences, which may also play a role in the functioning of the plant microbiome.

Diverse biological activities and secondary metabolites profile of Penicillium brevicompactum HE19ct isolated from the high-Andean medicinal plant Perezia coerulescens

Endophytic fungi produced attractive primary and secondary metabolites for industries, pharmacology, and biotechnology. The bioactive potential of HE19ct, identified as Penicillium brevicompactum according to ITS-BenA-caM, was addressed. Antimicrobial and antioxidant activities and secondary metabolite contents using four culture media in Agar-plate (ApF) and Submerged (SmF) fermentation were evaluated. Some plant growth-promoting (PGP) traits and their related genes were tested. HE19ct exhibited antimicrobial activity against Staphylococcus aureus, Enterococcus faecalis, Candida albicans, C. tropicalis, Fusarium sp., Geotrichum candidum, and Alternaria sp. All cultures showed DPPH scavenging activity and phenolic compounds, where ethyl acetate extract of SmF with malt extract showed higher activity and SmF/ApF with potato-dextrose exhibited higher yield, respectively. HE19ct solubilized tricalcium-phosphate and produced siderophore, endoglucanase, proteinase, and amylase. It enhanced the alfalfa's germination at 15 °C, root development, and phenols production at 15 and 24 °C. Phenols, tannins, anthraquinones, triterpenoids/steroids, and alkaloids production were detected depending on culture media. Polyketide synthase type I gene (PksI), subtilisin-like protease prb 1 (Pbr), and siderophore D (sidD) were PCR-amplified. Finally, HE19CT could be a promising source of interesting bioactive compounds for pharmacology and agriculture mainly in extreme conditions, then metabolomic and functional genetic research must be performed to support their appropriate application.

Qualitative Identification of Secondary Metabolites and Determination of the Toxicity of Extracts Obtained from the Flower of Kalanchoe Pinnata

Kalanchoe pinnata, also known as air leaf or life leaf, is a plant used in traditional medicine in different world regions. In Mexico, it is included in the Atlas de la Medicina Tradicional Mexicana with a wide variety of applications, such as antimicrobial, anti-inflammatory, anticancer, and antihistamine, among others. However, neither a secondary metabolite profile of the flower has been reported nor information on its possible toxicity. The latter is the purpose of this work. A phytochemical profile of extracts with solvents of different polarity (aqueous, methanol, ethanol, and ether) was carried out. In this profile, the structural compounds could be qualitatively determined by chemical reactions, and some changes in coloring or precipitation were observed. The acute toxicity test of the extracts was performed with an aquatic organism, Artemia sp, and a terrestrial organism Eisenia foetida, as well as the evaluation of the antioxidant capacity of the extracts in the organism of Eisenia foetida. The ABTS radical method and TROLOX were applied as synthetic antioxidants for the evaluation of the inhibition percentage. Most important secondary metabolites were qualitatively identified in the extracts of K. pinnata flowers. Mainly in the alcoholic extracts (methanol and ethanol) tannins, alkaloids, and flavonols were found. As mentioned above, they are reported to have toxicological effects. The toxicity and antioxidant activity tests confirm the preliminary results obtained in the identification of secondary metabolites. It is therefore concluded that the flower of Kalanchoe pinnata contains secondary metabolites that may be of great therapeutic interest.

De novo transcriptome profiling and development of novel secondary metabolites based genic SSRs in medicinal plant Phyllanthus emblica L. (Aonla)

Phyllanthus emblica (Aonla, Indian Gooseberry) is known to have various medicinal properties, but studies to understand its genetic structure are limited. Among the various secondary metabolites, ascorbic acid, flavonoids, terpenoids, phenols and tannins possess great potential for its pharmacological applications. Keeping this consideration, we assembled the transcriptome using the Illumina RNASeq500 platform, generating 39,933,248 high-quality paired-end reads assembled into 1,26,606 transcripts. A total of 87,771 unigenes were recovered after isoforms and unambiguous sequences deletion. Functional annotation of 43,377 coding sequences against the NCBI non-redundant (Nr) database search using BlastX yielded 38,692 sequences containing blast hits and found 4685 coding sequences to be unique. The transcript showed maximum similarity to Hevea brasilensis (16%), followed by to Jatropha curcas (12%). Considering key genes involved in the biosynthesis of flavonoids and various classes of terpenoid compounds, thirty EST-SSR primer sequences were designed based on transcriptomic data. Of which, 12 were found to be highly polymorphic with an average of 86.38%. The average value for marker index (MI), effective multiplicity ratio (EMR), resolution power (Rp) and polymorphic information content (PIC) was 7.20, 8.34, 8.64 and 0.80, respectively. Thus, from this study, we developed newly EST-SSRs linked to important genes involved in the secondary metabolites biosynthesis that will be serving as an invaluable genetic resource for crop improvement including the selection of elite genotypes in P. emblica and its closely related Phyllanthaceae species.

Determination of Total Phenolic Content, Secondary Metabolite Profile from Mangosteen Leaf Extract and Its Potential Utilization in Herbal Tea Preparations as Anticancer

Background; Mangosteen leaves (Garcinia mangostana L.) have secondary metabolites, namely phenolics, flavonoids, tannins, saponins, and triterpenoids. Phenolics are one of the largest groups of compounds found in mangosteen leaves which have several pharmacological and therapeutic functions, one of which is anti-cancer. Objectives; To determine the total phenol content and profile of secondary metabolites and the type of phenolic extract of mangosteen leaves. Method; Using UV-Vis spectrophotometer Folin-Ciocalteu method with the gallic acid standard. Profile of secondary metabolites and phenolic types using LCMS. Results; Based on the research that has been done, the total phenolic content is obtained where the highest concentration is in the ethanol extract 96% (290.90 mg GAE/g extract or 29.08%), then ethyl acetate extract (161.07 mg GAE/g extract or 16, 10%). Identification of LCMS, detected 15 compounds, including 6 phenolic compounds. Phenolic compounds found were gallic acid, amarogentin, oleuropein glucoside, mandelic acid, vanillic acid, and gentisic acid.. Conclusion; Phenolic compounds can act as antioxidants by protecting body cells from damage caused by free radicals such as degenerative diseases, one of which is cancer due to free radical induction.

Exogenous ʟ-tryptophan treatment increases the concentrations of melatonin and aroma compounds in grape berries and wine

Abstract l-Tryptophan (Trp) is a substrate for the biosynthesis of melatonin, and melatonin is a signal molecule that alters the secondary metabolite profile; whether Trp treatments promote the biosynthesis of melatonin to regulate aroma compounds in grape berries and wine remains unclear. Here, the content of melatonin was higher in Marselan grapes and wine than that in other grape cultivars. Marselan grapes were subjected to 30 different Trp treatments. The content of melatonin and aroma compounds in Marselan grapes was increased by several treatments. Increases in the content of volatiles were mainly driven by increases in aldehydes. Hexanal, the most abundant aldehyde compound, was the main contributor to increases in aldehydes following Trp treatment. The results of our study indicate that the root application of 250 mg/L l-tryptophan during the fruiting expansion stage and the spraying application of 50 mg/L l-tryptophan spray during the veraison stage were the optimal treatments because the content of melatonin and aroma compounds, as well as other basic quality parameters, were highest in Trp-treated grape berries and wine in these treatments. Overall, these two effective Trp treatments could be used to enhance the content of melatonin and aroma compounds in Marselan grapes, and this could increase the economic value of this cultivar.

Antioxidant Properties and Secondary Metabolites Profile of Hyptis colombiana at Various Phenological Stages.

Hyptis colombiana (Lamiaceae family), a species also treated as Cantinoa colombiana in a recently segregated genus from Hyptis, is a perennial herb or subshrub native to the Andes of northern South America. H. colombiana leaves are commonly used in traditional medicine to treat respiratory and digestive illnesses. In this study, H. colombiana plants at different phenological stages (vegetative, flowering, and post-flowering) were harvested to obtain essential oils (EOs) and extracts (from fresh plant materials or post-distillation waste) whose chemical compositions and antioxidant activities were determined. H. colombiana EOs distilled by microwave-assisted hydrodistillation were analyzed by GC/MS/FID, and hydroalcoholic extracts obtained from fresh plant materials or post-distillation waste were analyzed by UHPLC-ESI+/--Orbitrap-MS. The antioxidant activity was evaluated by the ABTS+• and ORAC assays. The principal compounds found in EOs were sesquiterpene hydrocarbons (65%); specifically, (E)-β-caryophyllene and germacrene D. Pyranone, rosmarinic acid, rutin, and p-hydroxybenzoic acid were the main constituents in H. colombiana extracts. After analyzing the chemical composition and antioxidant activity (ORAC) of EOs and hydroethanolic extracts from flowering H. colombiana plants, minimal variations were found. It is advisable to harvest H. colombiana plants during their flowering stage to acquire EOs and extracts that can be utilized in the agro-industry of EOs and their natural derivatives.

Identification of metabolite profiles of local cowpeas (Vigna unguiculata L. Walp) from Southwest Maluku, Indonesia

Cowpea is considered an important food in the Southwest Maluku (SWM) District with high morphogenetic diversity. However, information on nutrition and metabolite profiles of the cowpea from SWM has been unrevealed for a new food ingredient for local people of SWM. The laboratory work was conducted descriptively to reveal the nutrient composition of the metabolite profile of some local cowpeas from SWM, Indonesia using High-Performance Liquid Chromatography (HPLC) and Gas Chromatography -Mass Spectrometry (GC-MS) methods. Key chemical profiles of amino acids, fatty acids, flavonoids, phenolic acids, and other secondary metabolites in cowpeas were analyzed using PCA. The results showed that there were fifteen amino acids, 35 fatty acids, and 52 secondary metabolites identified. The highest amino acid content found in all varieties was glutamic acid at 4.32 ± 0.31%. The highest fatty acid content was identified as arachidic acid at 15.83 ± 3.94%. The plant sterol identified in all varieties was stigmasterol with an average of 3.05 ± 0.43%. The KM7 variety had the highest amino acid in contrast to the KM6 variety. The highest stigmasterol, total flavonoids, and total phenolic content were found in the KM3 variety. These results reveal that local cowpeas have the potential for nutritional and functional food development.

Therapeutic potential of the genus Zanthoxylum phytochemicals: A theoretical ADME/Tox analysis

Natural products (NPs) are essential in the search for new drugs to treat a wide range of diseases, including infectious and malignant disorders. However, despite the discovery of many bioactive NPs, they often do not make it to market as drugs due to toxicity and other challenges. The development of NPs into drugs is a long and expensive process, and many promising compounds are abandoned along the way. These molecules require in silico ADMET profiling in order to speed up their development into drugs lower costs, and the high attrition rate. The objective of this work was to produce thorough ADMET profiles of secondary metabolites from several classes that were isolated from Zanthoxylum species. The genus has a long history of therapeutic use, including treating tumours, hypertension, gonorrhea, coughs, bilharzia, chest pains, and toothaches. The study used a dataset of 406 compounds from the genus for theoretical ADMET analysis. The findings revealed that 81% of the compounds met Lipinski's rule of five, indicating good oral bioavailability. The drug-likeness criteria were taken into account, with percentages ranging from 66.2 to 88.1 percent. Additionally, 9.2% of the compounds were predicted to be lead-like, demonstrating their potential as promising drug development candidates. Interestingly, none of the compounds inhibited hERG I, while 33% inhibited hERG II, potentially having cardiac implications. Additionally, 30% of the compounds exhibited AMES toxicity inhibition, while 23.6% were identified as hepatotoxic and 22.2% would cause skin sensitivity. Moreover, 81.8% of the compounds demonstrated high intestinal absorption, making them desirable for oral drugs. In conclusion, these findings highlight the diverse properties of the investigated compounds and their potential for drug development.

Metabolome profiling of arbuscular mycorrhizal fungus treated Ocimum tenuiflorum L. provides insights into deviation in allocation of carbon compounds to secondary metabolism

Arbuscular mycorrhiza (AM) has been reported to influence secondary metabolism of Ocimum tenuiflorum L., thereby improving its therapeutic and commercial importance. To explain changes in the secondary metabolite profile, the study reports effects of AM on leaf metabolome of two high yielding genotypes of O. tenuiflorum inoculated with Rhizophagus intraradices. NMR-based non-targeted metabolic fingerprinting was related to changes at physiological, biochemical, and molecular levels in mycorrhizal (M) plants. AM resulted in higher accumulation of sucrose, which could be related with enhanced photosynthesis by virtue of increased uptake of mineral nutrients. A strong positive correlation between sucrose and net photosynthetic rate and sucrose and mineral nutrients supported that AM-mediated increase in uptake of mineral nutrients is associated with enhanced photosynthetic rate and accumulation of sucrose. Further, higher sucrose synthase activity resulted in increased glucose. Hexokinase activity was also higher in M plants resulting in higher pyruvate accumulation. On the contrary, Krebs cycle was compromised in M plants as evident by lower activities of its enzymes and concentrations of organic and amino acids. Nevertheless, AM increased activities and expressions of enzymes of terpenoid biosynthesis, shikimate, and phenylpropanoid pathways, thereby resulting in augmented production of terpenoids, phenylalanine, and phenols, respectively. Thus, metabolic reprogramming downstream of glycolysis was apparent wherein AMF resulted in more allocation of carbon resources to secondary metabolism as opposed to primary metabolism, which was supported by Pearson's correlation analysis. Higher C:N ratio in M plants explains the provision of more carbon resources to secondary metabolism as against primary metabolism.

Use of Secondary Metabolites Profiling and Antioxidant Activity to Unravel the Differences between Two Species of Nettle.

In recent years, the interest in natural remedies has increased, so it is important to analyze the plants widely distributed in nature but whose composition is little known. The main objective of the present work is to obtain information based on the profiles of secondary metabolites and antioxidant activity in Lamium album, a very widespread but little studied plant, with the aim of revealing the differences compared to Urtica dioica. First, the optimization of enzymatic extraction assisted by ultrasound was carried out by the Box-Behnken method. The optimized parameters were: concentration of the enzyme-3.3% cellulase, temperature-55 °C, and the extraction time-40.00 min. The efficiency was estimated based on the content of iridoids, the main class of secondary metabolites from Lamium album. Second, the secondary metabolites profiles of the nettle extracts were obtained by thin-layer chromatography using both normal and reverse phases and by RP-UHPLC. The antioxidant activity was evaluated using DPPH and ABTS+ radicals. The obtained results revealed significant differences between the two nettle species, both in terms of the phytochemical compounds, as well as the antioxidant activity, confirming the fact that Lamium album has a high potential to be used in phytomedicine.

Secondary metabolite profiling of Sphaerostephanos arbuscula (Wild.) Holttum. chloroform extracts by UHPLC and their biopotency

Secondary metabolite profiling of Sphaerostephanos arbuscula (Wild.) Holttum. chloroform extracts by UHPLC and their biopotency

Averrhoa carambola L. fruit and stem metabolites profiling and immunostimulatory action mechanisms against cyclosporine induced toxic effects in rat model as analyzed using UHPLC/MS-MS-based chemometrics and bioassays.

The Averrhoa carambola L. tree encompasses a myriad of phytochemicals contributing to its nutritional and health benefits. The current study aims at investigating the A. carambola L. the metabolite profile grown in tropical and temperate regions represented by fruit and stem, for the first time using UPLC/MS-based molecular networking and chemometrics. Asides, assessment of the immunostimulatory effect of ripe fruit and stem, was compared in relation to metabolite fingerprints. Eighty metabolites were identified, 8 of which are first-time to be reported including 3 dihydrochalcone-C-glycosides, 4 flavonoids, and one phenolic. Multivariate data analysis revealed dihydrochalcones as origin-discriminating metabolites between temperate and tropical grown fruits. Further, an in vivo immunomodulatory assay in a cyclosporine A-induced rat model revealed a potential immune-enhancing effect as manifested by down-regulation of inflammatory markers (IL-6, INF-γ, IL-1, TLR4, and ESR) concurrent with the up-regulation of CD4 level and the CD4/CD8 ratio. Moreover, both extracts suppressed elevation of liver and kidney functions in serum as well as reduction in oxidative stress with concurrent increased levels of T-protein, albumin, globulin, and A/G ratio. This study pinpoints differences in secondary metabolite profiles amongst A. carambola L. accessions from different origins and organ type and its immunomodulatory action mechanisms.

Design and validation of a PCR screen for γ-butyrolactone-like regulatory systems in Streptomyces.

γ-butyrolactone and related signalling systems are found in Streptomyces and other actinobacteria where they control the production of secondary or specialized metabolites such as antibiotics. Genetic manipulation of these regulatory systems therefore leads to changes in the secondary metabolite profile of a strain and has been used to activate previously silent secondary metabolite gene clusters. However, there is no easy way to assess the presence of γ-butyrolactone-like systems in Streptomyces strains without whole-genome sequencing. We have therefore developed and tested a PCR screen that is able to detect homologues of the commonly co-located butenolide synthase and γ-butyrolactone receptor genes. This PCR screen could be employed for the screening of strain libraries to detect signalling systems without the necessity for whole-genome sequencing.