Comprehensive metabolite profiling of Arum palaestinum (Araceae) leaves by using liquid chromatography–tandem mass spectrometry

Effects of Ultra-High-Pressure Treatment on Chemical Composition and Biological Activities of Free, Esterified and Bound Phenolics from Phyllanthus emblica L. Fruits

Phyllanthus emblica L. fruits (PEFs) were processed by ultra-pressure (UHP) treatment and then extracted by the ultrasonic-assisted extraction method. The influence of UHP on the phenolic composition, enzyme inhibitory activity and antioxidant activity of the free, esterified, and bound phenolic fractions from PEFs were compared. UHP pretreatment of PEFs significantly increased the total phenolic and flavonoid contents (p < 0.05). A total of 24 chemical compositions were characterized in normal and UHP-treated PEFs by UHPLC-ESI-HRMS/MS. Compared with normal PEFs, these three different phenolic fractions had stronger antioxidant activities and inhibitory effects on the intracellular reactive oxygen species (ROS) production in H2O2-induced HepG2 cells (p < 0.05). The ROS inhibition might be due to an up-regulation of the expressions of superoxide dismutase (SOD) and glutathione (GSH) activities. In addition, these three different phenolic fractions also significantly inhibited the activities of metabolic enzymes, including α-glucosidase, α-amylase and pancreatic lipase. This work may provide some insights into the potential economics and applications of PEFs in food and nutraceutical industries.

Rheological properties, biochemical changes, and potential health benefits of dehulled and defatted industrial hempseeds after fermentation

Dehulled hempseed (DHS), fermented dehulled hempseed (FDHS), hempseed cake (HSC), and fermented HSC (FHSC) were examined for their phytochemical composition, health benefits, and rheological characteristics. At 500 µg/mL concentration, DHS, FDHS, HSC, and FHSC extracts exhibited the ability to inhibit DPPH radicals, with 32.46 %, 47.35 %, 33.85 %, and 47.41 %, respectively. Similarly, they demonstrated potential to scavenge ABTS radicals by 13.7 %, 27.87 %, 14.40 % and 25.70 %, respectively. For lipase inhibition activity, FDHS (72.92 %) and FDHS (85.89 %) outperformed DHS (52.94 %) and HSC (43.08 %). Furthermore, FHSC enhanced the survival and reduced fat accumulation in glucose-supplemented Caenorhabditis elegans. We used HPLC and UHPLC-ESI-QTOF-MS for metabolite analysis, quantifying eight polyphenols using HPLC and identifying thirty-four metabolites with UHPLC-ESI-QTOF-MS. Generally, metabolomics indicated an improved metabolite profile after fermentation. Fermentation also showed impact on rheological characteristics, modifying viscosity, loss modulus, and storage modulus. These findings collectively demonstrate the ability of fermentation in enhancing overall value of hempseed.

Potential Anti-Tumorigenic Properties of Diverse Medicinal Plants against the Majority of Common Types of Cancer

Globally, cancer is one of the primary causes of both morbidity and mortality. To prevent cancer from getting worse, more targeted and efficient treatment plans must be developed immediately. Recent research has demonstrated the benefits of natural products for several illnesses, and these products have played a significant role in the development of novel treatments whose bioactive components serve as both chemotherapeutic and chemo-preventive agents. Phytochemicals are naturally occurring molecules obtained from plants that have potential applications in both cancer therapy and the development of new medications. These phytochemicals function by regulating the molecular pathways connected to the onset and progression of cancer. Among the specific methods are immune system control, inducing cell cycle arrest and apoptosis, preventing proliferation, raising antioxidant status, and inactivating carcinogens. A thorough literature review was conducted using Google Scholar, PubMed, Scopus, Google Patent, Patent Scope, and US Patent to obtain the data. To provide an overview of the anticancer effects of several medicinal plants, including Annona muricata, Arctium lappa, Arum palaestinum, Cannabis sativa, Catharanthus roseus, Curcuma longa, Glycyrrhiza glabra, Hibiscus, Kalanchoe blossfeldiana, Moringa oleifera, Nerium oleander, Silybum marianum, Taraxacum officinale, Urtica dioica, Withania somnifera L., their availability, classification, active components, pharmacological activities, signaling mechanisms, and potential side effects against the most common cancer types were explored.

Bioactive compounds from the leaves of Maytenus ilicifolia Mart. ex Reissek: Inhibition of LDL oxidation, glycation, lipid peroxidation, target enzymes, and microbial growth

ETHNOPHARMACOLOGICAL RELEVANCE

Maytenus ilicifolia Mart. ex Reissek, a medicinal plant used for treating gastritis, ulcers, and gastric disorders, possesses therapeutic properties attributed to diverse leaf compounds-terpenoids, alkaloids, flavonoids, phenols, and tannins, reflecting the ethnopharmacological knowledge of traditional users.

AIMS OF THE STUDY

We aimed to assess the antioxidant and antiglycant capacities of Maytenus ilicifolia's ethanolic extract and organic fractions, identify bioactive compounds through HPLC-MS/MS analysis, and conduct phytochemical assessments. We also assessed their potential to inhibit digestive and cholinesterase enzymes, mitigate oxidation of human LDL and rat hepatic tissue, and examine their antimicrobial and cytotoxic properties.

MATERIALS AND METHODS

Organic fractions (hexane - HF-Mi, dichloromethane - DMF-Mi, ethyl acetate - EAF-Mi, n-butanol - BF-Mi, and hydromethanolic - HMF-Mi) were obtained via liquid-liquid partitioning. Antioxidant (DPPH, FRAP, ORAC) and antiglycant (BSA/FRU, BSA/MGO, ARG/MGO/LDL/MGO models) capacities were tested. Phytochemical analysis employed HPLC-MS/MS. We also studied the inhibitory effects on α-amylase, acetylcholinesterase, butyrylcholinesterase, human LDL and rat hepatic tissue oxidation, antimicrobial activity, and cytotoxicity against RAW 264.7 macrophages.

RESULTS

HPLC-ESI-MS/MS identified antioxidant compounds such as catechin, quercetin, and kaempferol derivatives. Ethanolic extract (EE-Mi) and organic fractions demonstrated robust antioxidant and antiglycant activity. EAF-Mi and BF-Mi inhibited α-amylase (2.42 μg/mL and 7.95 μg/mL) compared to acarbose (0.144 μg/mL). Most organic fractions exhibited ∼50% inhibition of acetylcholinesterase and butyrylcholinesterase, rivaling galantamine and rivastigmine. EAF-Mi, BF-Mi, and EE-Mi excelled in inhibiting lipid peroxidation. All fractions, except HMF-Mi, effectively countered LDL oxidation, evidenced by the area under the curve. These fractions protected LDL against lipid peroxidation.

CONCLUSION

This study unveils Maytenus ilicifolia's ethanolic extract and organic fractions properties. Through rigorous analysis, we identify bioactive compounds and highlight their antioxidant, antiglycant, enzyme inhibition, and protective properties against oxidative damage. These findings underline its significance in modern pharmacology and its potential applications in healthcare.

Steroidal Alkaloids from Food Waste of Tomato Processing Inhibit Neuroblastoma Cell Viability

Nowadays, there is considerable attention toward the use of food waste from food processing as possible sources of compounds with health properties, such as anticancer activity. An example is tomato processing, which is responsible for generating a remarkable amount of waste (leaves, peel, seeds). Therefore, our goal was to evaluate the potential anticancer property of tomato extracts, in particular "Datterino" tomato (DT) and "Piccadilly" tomato (PT), and to study their phytochemical composition. Liquid chromatography with tandem mass spectrometry (LC/MS-MS) results showed that these extracts are rich in alkaloids, flavonoids, fatty acids, lipids, and terpenes. Furthermore, their potential anticancer activity was evaluated in vitro by MTT assay. In particular, the percentage of cell viability was assessed in olfactory ensheathing cells (OECs), a particular glial cell type of the olfactory system, and in SH-SY5Y, a neuroblastoma cell line. All extracts (aqueous and ethanolic) did not lead to any significant change in the percentage of cell viability on OECs when compared with the control. Instead, in SH-SY5Y we observed a significant decrease in the percentage of cell viability, confirming their potential anticancer activity; this was more evident for the ethanolic extracts. In conclusion, tomato leaves extracts could be regarded as a valuable source of bioactive compounds, suitable for various applications in the food, nutraceutical, and pharmaceutical fields.

Profiling of primary and phytonutrients in edible mahlab cherry (Prunus mahaleb L.) seeds in the context of its different cultivars and roasting as analyzed using molecular networking and chemometric tools

Prunus mahaleb L. (mahlab cherry) is a deciduous plant that is native to the Mediterranean region and central Europe with a myriad of medicinal, culinary and cosmetic uses. The present study explored different cultivars of mahlab (white from Egypt and Greece, red from Egypt and post roasting). UPLC-MS led to the detection of 110 primary and secondary metabolites belonging to different classes including phenylpropanoids (hydroxy cinnamates, coumaroyl derivatives), organic acids, coumarins, cyanogenic glycosides, flavonoids, nitrogenous compounds, amino acids and fatty acids, of which 39 are first time to be detected in Prunus mahaleb L. A holistic assessment of metabolites was performed for further analysis of dataset using principal component analysis (PCA) among mahlab cultivars to assess variance within seeds. The results revealed that phenolic acids (coumaric acid-O-hexoside, ferulic acid-O-hexoside, ferulic acid-O-hexoside dimer, dihydrocoumaroyl-O-hexoside dimer and ferulic acid), coumarins (coumarin and herniarin) and amino acids (pyroglutamic acid) were abundant in white mahlab cultivars (cvs.) from different locations. In contrast, red mahlab and its roasted seeds were more rich in organic acids (citric and malic acids), amygdalin derivative and sphingolipids. Orthogonal projections to latent structures discriminant analysis (OPLS-DA) revealed for markers in red mahlab and in response to roasting, where red mahlab was rich in nitrogenous compounds viz. nonamide, deoxy fructosyl leucine, glutaryl carnitine and isoleucine, while roasted product (REM) was found to be enriched in choline.

Orbitrap Mass Spectrometry-Based Profiling of Secondary Metabolites in Two Unexplored Eminium Species and Bioactivity Potential

The study aimed at the metabolite profiling and evaluation of antioxidant and enzyme inhibitory properties of methanol extracts from flowers, leaves, and tubers of unexplored Eminium intortum (Banks & Sol.) Kuntze and E. spiculatum (Blume) Schott (Araceae). A total of 83 metabolites, including 19 phenolic acids, 46 flavonoids, 11 amino, and 7 fatty acids were identified by UHPLC-HRMS in the studied extracts for the first time. E. intortum flower and leaf extracts had the highest total phenolic and flavonoid contents (50.82 ± 0.71 mg GAE/g and 65.08 ± 0.38 RE/g, respectively). Significant radical scavenging activity (32.20 ± 1.26 and 54.34 ± 0.53 mg TE/g for DPPH and ABTS) and reducing power (88.27 ± 1.49 and 33.13 ± 0.68 mg TE/g for CUPRAC and FRAP) were observed in leaf extracts. E. intortum flowers showed the maximum anticholinesterase activity (2.72 ± 0.03 mg GALAE/g). E. spiculatum leaves and tubers exhibited the highest inhibition towards α-glucosidase (0.99 ± 0.02 ACAE/g) and tirosinase (50.73 ± 2.29 mg KAE/g), respectively. A multivariate analysis revealed that O-hydroxycinnamoylglycosyl-C-flavonoid glycosides mostly accounted for the discrimination of both species. Thus, E. intortum and E. spiculatum can be considered as potential candidates for designing functional ingredients in the pharmaceutical and nutraceutical industries.

Protective effects of a chemically characterized extract from solanum torvum leaves on acetaminophen-induced liver injury

Distinct parts of Solanum torvum Swartz. (Solanaceae) are popularly used for a variety of therapeutic purposes. This study determined the phytochemical composition of a phenolic fraction of S. torvum leaf aqueous extract and investigated its antioxidant and liver-protective properties. A phenolic compound-enriched fraction, or phenolic fraction (STLAE-PF) of an infusion (STLAE) of S. torvum leaves, was tested in vitro (antagonism of H₂O₂ in cytotoxicity and DCF assays with HepG2/C3A cells), and in vivo for antioxidant activity and protective effects against acetaminophen (APAP)-induced liver injury in mice. Thirty-eight compounds (flavonoids, esters of hydroxycinnamic acid, and chlorogenic acid isomers) were tentatively identified (high-performance liquid chromatography coupled to high-resolution electrospray mass spectrometry) in the STLAE-PF fraction. In vitro assays in HepG2/C3A cells showed that STLAE-PF and some flavonoids contained in this phenolic fraction, at noncytotoxic levels, antagonized in a concentration-dependent manner the effects of a powerful oxidant agent (H₂O₂). In C57BL/6 mice, oral administration of STLAE (600 and 1,200 mg/kg bw) or STLAE-PF (300 mg/kg bw) prevented the rise in serum transaminases (ALT and AST), depletion of reduced glutathione (GSH) and elevation of thiobarbituric acid reactive species (TBARs) levels in the liver caused by APAP (600 mg/kg bw, i.p.). The hepatoprotective effects of STLAE-PF (300 mg/kg bw) against APAP-caused liver injury were comparable to those of N-acetyl-cysteine (NAC 300 or 600 mg/kg bw i.p.). These findings indicate that a phenolic fraction of S. torvum leaf extract (STLAE-PF) is a new phytotherapeutic agent potentially useful for preventing/treating liver injury caused by APAP overdosing.

Effect of Common Cooking and Drying Methods on Phytochemical and Antioxidant Properties of Corchorus olitorius Identified Using Liquid Chromatography-Mass Spectrometry (LC-MS)

In this study, Corchorus olitorius leaves were subjected to different thermal treatments (blanching, boiling, drying, frying, and steaming) and analyzed, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity. Furthermore, Fourier transform infrared spectroscopy (FTIR) was used to identify functional groups, while metabolites were identified with LC-MC. The TPC and antioxidant activity of C. olitorius were significantly (p < 0.05) increased by cooking and drying. The steam-cooked sample had the highest TPC (18.89 mg GAE/g) and TFC (78.42 mg QE/g). With ABTS, FRAP, and DPPH assays, the steam-cooked sample exhibited the highest antioxidant activity of 119.58, 167.31, and 122.23 µM TE/g, respectively. LC-MS identified forty-two (42) metabolites in C. olitorius that included phenolic acid derivatives, flavonoid derivatives, and amino acid derivatives. Overall, steaming appears to be the best cooking method, with respect to the retention of phytochemical compounds and antioxidant activity.

Cyanogenesis in Aralia spinosa (Araliaceae)

A systematic survey of Aralia spinosa (Araliaceae), covering an entire growing season and including aboveground organs at various developmental stages, revealed that only about half of all samples collected showed cyanogenesis. Cyanogenesis was detected in inflorescences and leaves but is apparently restricted to certain harvest times or developmental stages. The structurally unusual triglochinin, characterized by a hex-2-enedioic acid partial structure, was the only cyanogenic glycoside detected. This is the first description of triglochinin in this species and in the family of Araliaceae. Triglochinin is biogenetically derived from tyrosine, which is in good agreement with the few cyanogenic glycosides previously detected in members of the Araliaceae family. Triglochinin was identified, characterized, and quantified by modern chromatographic methods, and the amount of enzymatically releasable hydrocyanic acid was determined qualitatively and quantitatively. Two isomers of triglochinin were detected chromatographically at minor levels. The isomeric pattern agreed well with literature data from other triglochinin-containing plants. This was confirmed in the two species, Triglochin maritima and Thalictrum aquilegiifolium, which were comparatively studied. In the case of A. spinosa, inflorescence buds harvested in July showed the highest content of triglochinin, just under 0.2% on a dry weight basis. The detection of triglochinin adds to the knowledge of toxicological properties and the dereplication of U(H)PLC/MS² data provides a comprehensive phytochemical profile of A. spinosa.

Plant Metabolomics as a Tool for Detecting Adulterants in Edible Plant: A Case Study of Allium ursinum

Allium ursinum and poisonous adulterants Convallaria majalis and Arum maculatum were used as a model for detection of adulterants in edible plant. A. ursinum samples were spiked with C. majalis and A. maculatum to mimic adulteration. Metabolomic fingerprinting of all samples was performed using ¹H NMR spectroscopy, and the resulting data sets were subjected to multivariate data analysis. As a result of this analysis, signals of adulterants were extracted from the data, and the structures of biomarkers of adulteration from partially purified samples were elucidated using 2D NMR and LC-MS techniques. Thus, isovitexin and vicenin II, azetidine-2-carboxylic acid, and trigonelline indicated adulteration of A. ursinum samples with C. majalis. Isovitexin was also recognized to be an indicator of adulteration of A. ursinum with A. maculatum. In conclusion, the case study of A. ursinum suggested that plant metabolomics approach could be utilized for identification of low molecular weight biomarkers of adulteration in edible plants.

Antimicrobial, Antivirulence, and Antiparasitic Potential of Capsicum chinense Jacq. Extracts and Their Isolated Compound Capsaicin

Bacterial, fungal, and parasitic infections increase morbimortality rates and hospital costs. This study aimed to assess the antimicrobial and antiparasitic activities of the crude extract from the seeds and peel of the pepper Capsicum chinense Jacq. and of the isolated compound capsaicin and to evaluate their ability to inhibit biofilm formation, eradicate biofilm, and reduce hemolysin production by Candida species. The crude ethanolic and hexane extracts were obtained by maceration at room temperature, and their chemical compositions were analyzed by liquid chromatography coupled to mass spectrometry (LC–MS). The antimicrobial activity of the samples was evaluated by determining the minimum inhibitory concentration. Inhibition of biofilm formation and biofilm eradication by the samples were evaluated based on biomass and cell viability. Reduction of Candida spp. hemolytic activity by the samples was determined on sheep blood agar plates. The antiparasitic action of the samples was evaluated by determining their ability to inhibit Toxoplasma gondii intracellular proliferation. LC–MS-ESI analyses helped to identify organic and phenolic acids, flavonoids, capsaicinoids, and fatty acids in the ethanolic extracts, as well as capsaicinoids and fatty acids in the hexane extracts. Antifungal action was more evident against C. glabrata and C. tropicalis. The samples inhibited biofilm formation and eradicated the biofilm formed by C. tropicalis more effectively. Sub-inhibitory concentrations of the samples significantly reduced the C. glabrata and C. tropicalis hemolytic activity. The samples only altered host cell viability when tested at higher concentrations; however, at non-toxic concentrations, they reduced T. gondii growth. In association with gold standard drugs used to treat toxoplasmosis, capsaicin improved their antiparasitic activity. These results are unprecedented and encouraging, indicating the Capsicum chinense Jacq. peel and seed extracts and capsaicin display antifungal and antiparasitic activities.

Influence of different pretreatments and drying methods on the chemical compositions and bioactivities of Smilacis Glabrae Rhizoma

Background

The processing of medicinal plant materials is one of the important factors influencing the components and biological activities of TCMs. Smilax glabra Roxb. is an herbal vine widely distributed in China, and its dried rhizome (Smilacis Glabrae Rhizoma, SGR) is often used in traditional medicines and functional foods. The processing methods of fresh cutting for SGR slices have been included in ancient Chinese herbal works, some local standards of TCMs, and the current Chinese Pharmacopoeia. Nevertheless, to date, the scientific basis for the processing of fresh medicinal materials for SGR slices has not been revealed.

Methods

To optimize the processing method for preparing SGR slices from the fresh rhizomes, the chemical compositions of the un-pretreated and pretreated (boiling, steaming) samples before and after drying (sun-drying, shade-drying, oven-drying), and the contents of astilbin isomers in dried SGR were analyzed by UHPLC-Q-TOF-MS/MS and UHPLC-DAD methods, respectively. Then, the antioxidant, anti-inflammatory, xanthine oxidase and α-glucosidase inhibitory activities of the prepared SGR slices were investigated by biological assays.

Results

A total of fifty-two compounds were identified from the un-pretreated and pretreated samples and a total of forty-nine compounds were identified from the subsequently dried samples. After pretreated by boiling and steaming, the contents of neoastilbin, neoisoastilbin, and isoastilbin in the prepared samples all increased. As a quality marker of SGR, the content of astilbin was unchanged or decreased slightly compared with that in the un-pretreated samples. During the drying process, the contents of the four astilbin stereoisomers in the un-pretreated samples increased significantly, while those in the pretreated samples had a slight increase or decrease. The effects of different processing methods were sorted according to the bioactivities of the prepared SGR. As a result, SGR slices prepared with no pretreatment followed by a sun-drying process have a higher astilbin content, better bioactivities and more energy savings, representing the optimum processing method for SGR slices.

Conclusions

This study reveals the scientific basis for the processing of fresh medicinal materials for SGR slices. The results provide scientific information for the quality control of SGR and its rational applications in herbal medicines and functional foods.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-022-00614-7.

Characterization of Phenethyl Cinnamamide Compounds from Hemp Seed and Determination of Their Melanogenesis Inhibitory Activity

Hyperpigmentation is induced by the overactivation of tyrosinase, which is a rate-limiting enzyme in melanogenesis. The defatted extract of hemp (Cannabis sativa L.) seed is known to have inhibitory effects on melanogenesis; however, effective compounds in the extract have not been identified yet. In this study, three phenethyl cinnamamides present in hemp seed extract were prepared by purification and chemical synthesis and were assessed for their inhibitory effect on melanogenesis in B16F10 melanoma cells. A comparison of the anti-melanogenesis and anti-tyrosinase activity of hemp seed solvent fractions revealed that the ethyl acetate fraction possessed the greatest potential for suppressing melanogenesis in melanoma cells by decreasing tyrosinase activity. We tentatively identified 26 compounds in the ethyl acetate fraction by comparing spectroscopic data with the literature. Three phenethyl cinnamamides such as N-trans-caffeoyltyramine, N-trans-coumaroyltyramine, and N-trans-feruloyltyramine present abundantly in the ethyl acetate fraction were prepared and their anti-melanogenesis and anti-tyrosinase activities in melanoma cells were evaluated. We found that N-trans-caffeoyltyramine and N-trans-feruloyltyramine inhibited alpha melanocyte stimulating hormone (α-MSH)-induced melanogenesis without cytotoxicity, while N-trans-coumaroyltyramine inhibited melanogenesis with cytotoxicity. IC₅₀ values of N-trans-caffeoyltyramine, N-trans-feruloyltyramine, and N-trans-coumaroyltyramine for inhibition of α-MSH-mediated tyrosinase activation were 0.8, 20.2, and 6.3 μM, respectively. Overall, N-trans-caffeoyltyramine possessed the strongest anti-melanogenesis activity among the three phenethyl cinnamamides evaluated. The inhibitory effect of N-trans-caffeoyltyramine was verified by determining the melanin content and tyrosinase activity in melanoma after treating the cells with synthetic compounds. Thus, N-trans-caffeoyltyramine isolated from hemp seed extract could be useful in cosmetics as a skin-whitening agent.

Comparative metabolomics reveals the cytotoxic and anti-inflammatory discriminatory chemical markers of raw and roasted colocynth fruit (Citrullus colocynthis L.)

Colocynth has a long history of use in traditional medicine for treatment of various inflammatory diseases where it is commonly roasted before being applied for medical purposes to reduce its toxicity. This study aims at tracking the effect of heat processing on the metabolic profile of the peels, pulps and seeds of colocynth fruit using UPLC-QqQ-MS-based metabolomics. The analysis resulted in tentative identification of 72 compounds belonging to different chemical classes. With roasting, a decline was observed in the relative amounts of chemical constituents where 42, 25 and 29 compounds were down-regulated in the peels, pulps and seeds, respectively. EC₁₀₀ values resulting in 100% cell viability were all higher in roasted samples compared to their relevant raw ones. Correlation analysis indicated that the main cytotoxic chemical markers were cucurbitacin glycosides and their genins. Further, ex vivo anti-inflammatory activity testing multivariate models revealed that unprocessed samples correlated with inhibition of TNF-α, IL-1β and IFN-γ where quercetrin, calodendroside A, and hexanoic acid methyl ester were the most significant chemical markers, while processed samples showed correlation with IL-6 pro-inflammatory marker inhibition with protocatechuic and protocatechuic acid glycoside being the main correlated chemical markers.

Colocynth has a long history of use in traditional medicine for treatment of various inflammatory diseases where it is commonly roasted before being applied for medical purposes to reduce its toxicity.

LC-MS/MS profiling, antibiofilm, antimicrobial and bacterial growth kinetic studies of Pluchea dioscoridis extracts

The therapeutical applications of ornamental plants have been categorized to be of a great effectiveness in multiple industries from ancient times until present days. Pluchea dioscoridis is widely known Egyptian wooden plant that has been extensively applied for different medicinal purposes. In this study, LC-ESI-MS/MS analysis of the potent antimicrobial ethyl acetate and n-butanol extracts of P. dioscoridis leaves led to identification of 28 and 21 compounds, respectively. The identified compounds were categorized as phenolic acids, phenolic acids derivatives, organic acids, flavonoids (aglycones and glycosides), secoiridoids, coumarin derivatives, and gallotannins derivatives. Among them, caffeic acid 3-sulfate was the most predominate in the investigated extracts followed by ferulic acid and dicaffeoyl-quinic acid. Also, the antimicrobial potentiality of different extracts was evaluated against different pathogenic microbes including Enterobacter cloacae, Micrococcus leutus, Aeromonas hydrophila, Bacillus subtilis, Bacillus cereus, Bacillus lichneformis and Clostridium species. Furthermore, different concentrations of the most potent extract were assayed for antibacterial efficacy on growth curve kinetics against the susceptible bacteria along 4days incubation period. Our gathered data confirmed that, the antimicrobial activity against tested bacteria was different according to the solvent used in the extraction process. Mostly, all the extracts showed a wide spectrum antibacterial activity except the plant water extract which shows a mild activity against Clostridium sp. only. Based on the highest inhibition zone diameter, the ethyl acetate extract followed by butanol extract exhibited the highest inhibition zone with Micrococcus luteus and B. subtilis (20.0 and 18.5 mm) respectively. Determining the effect of ethyl acetate extract at different concentration (0, 0.66, 1.66, 3.33, 6.67, 13.34 and 20.01 mg mL−1) on M. luteus growth kinetics, the data assured that the antibacterial activity shows concentration dependent manner with the highest antibacterial activity at 20.01 mg mL−1 culture. The data also confirmed that, none of the selected concentration showed bactericidal activity in the prepared cultures, and with the prolonged incubation period the bacteria acquire resistance against the extract beginning from second or third day of incubation.

Effect of solvent polarity on the Ultrasound Assisted extraction and antioxidant activity of phenolic compounds from habanero pepper leaves (Capsicum chinense) and its identification by UPLC-PDA-ESI-MS/MS

Phenolic compounds are secondary metabolites involved in plant adaptation processes. The development of extraction procedures, quantification, and identification of this compounds in habanero pepper (Capsicum chinense) leaves can provide information about their accumulation and possible biological function. The main objective of this work was to study the effect of the UAE method and the polarity of different extraction solvents on the recovery of phenolic compounds from C. chinense leaves. Quantification of the total phenolic content (TPC), antioxidant activity (AA) by ABTS+ and DPPH radical inhibition methods, and the relation between the dielectric constant (ε) as polarity parameter of the solvents and TPC using Weibull and Gaussian distribution models was analyzed. The major phenolic compounds in C. chinense leaves extracts were identified and quantified by UPLC-PDA-ESI-MS/MS. The highest recovery of TPC (24.39 ± 2.41 mg GAE g-1 dry wt) was obtained using MeOH (50%) by UAE method. Correlations between TPC and AA of 0.89 and 0.91 were found for both radical inhibition methods (ABTS+ and DPPH). The Weibull and Gaussian models showed high regression values (0.93 to 0.95) suggesting that the highest phenolic compounds recovery is obtained using solvents with "ε" values between 35 and 52 by UAE. The major compounds were identified as N-caffeoyl putrescine, apigenin, luteolin and diosmetin derivatives. The models presented are proposed as a useful tool to predict the appropriate solvent composition for the extraction of phenolic compounds from C. chinense leaves by UAE based on the "ε" of the solvents for future metabolomic studies.

Advances in Research on the Preparation and Biological Activity of Maslinic Acid

Maslinic acid, a pentacyclic triterpene acid, is mainly isolated from olives. Maslinic acid and its derivatives exhibit a broad range of biological properties, such as anti-inflammatory, anticancer, anti-diabetic, antimicrobial, neuroprotective and hepatoprotective activities. In this minireview, the progress of research on maslinic acid with regard to its bioactivities, extraction, semisynthetic preparation and patents is reported. The relationships between the structure and the activity of maslinic acid and its derivatives are also discussed.

Ultrasound-Assisted Extraction Optimization of α-Glucosidase Inhibitors from Ceratophyllum demersum L. and Identification of Phytochemical Profiling by HPLC-QTOF-MS/MS

Ceratophyllum demersum L. (CDL) is a traditional Chinese herb to treat many diseases, but research on its anti-diabetic activity is not available. In this research, the α-glucosidase inhibitory ability and phytochemical constituents of CDL extract were firstly studied. Optimal ultrasound-assisted extraction conditions for α-glucosidase inhibitors (AGIs) were optimized by single factor experiment and response surface methodology (RSM), which was confirmed as 70% methanol, liquid-to-solid ratio of 43 (mL/g), extraction time of 54 min, ultrasonic power of 350 W, and extraction temperature of 40 °C. The lowest IC₅₀ value for α-glucosidase inhibition was 0.15 mg dried material/mL (mg DM/mL), which was much lower than that of acarbose (IC₅₀ value of 0.64 mg DM/mL). In total, 80 compounds including 8 organic acids, 11 phenolic acids, 25 flavonoids, 21 fatty acids, and 15 others were identified or tentatively identified from CDL extract by HPLC-QTOF-MS/MS analysis. The results suggested that CDL could be a potential source of α-glucosidase inhibitors. It can also provide useful phytochemical information for research into other bioactivities.

Characterization of a sweet basil acyltransferase involved in eugenol biosynthesis

Sweet basil (Ocimum basilicum) plants produce its characteristic phenylpropene-rich essential oil in specialized structures known as peltate glandular trichomes (PGTs). Eugenol and chavicol are the major phenylpropenes produced by sweet basil varieties whose synthetic pathways are not fully elucidated. Eugenol is derived from coniferyl acetate by a reaction catalysed by eugenol synthase. An acyltransferase is proposed to convert coniferyl alcohol to coniferyl acetate which is the first committed step towards eugenol synthesis. Here, we perform a comparative next-generation transcriptome sequencing of different tissues of sweet basil, namely PGT, leaf, leaf stripped of PGTs (leaf-PGT), and roots, to identify differentially expressed transcripts specific to PGT. From these data, we identified a PGT-enriched BAHD acyltransferase gene ObCAAT1 and functionally characterized it. In vitro coupled reaction of ObCAAT1 with eugenol synthase in the presence of coniferyl alcohol resulted in eugenol production. Analysis of ObCAAT1-RNAi transgenic lines showed decreased levels of eugenol and accumulation of coniferyl alcohol and its derivatives. Coniferyl alcohol acts as a common substrate for phenylpropene and lignin biosynthesis. No differences were found in total lignin content of PGTs and leaves of transgenic lines, indicating that phenylpropene biosynthesis is not coupled to lignification in sweet basil.

Chemical profile, liver protective effects and analgesic properties of a Solanum paniculatum leaf extract

BACKGROUND/AIM

Solanum paniculatum L. (Solanaceae) is a plant native to South America where it is used in traditional medicine for different therapeutic indications. This study evaluated the chemical composition and the hepatoprotective and analgesic activities of S. paniculatum leaf extracts.

MATERIAL AND METHODS

The chemical profile of an ethyl acetate partition (SPOE) of a S. paniculatum leaf infusion (SPAE) was analysed by high performance liquid chromatography coupled to high-resolution electrospray mass spectrometry (HPLC-ESIMS). Liver protective effects of SPAE (600 and 1200 mg/kg bw, po), or SPOE (300 mg/kg bw, po) were evaluated in a C57BL/6 mouse model of acetaminophen (AP, 600 mg/kg bw, ip) hepatotoxicity by measuring alanine (ALT) and aspartate (AST) aminotransferase activity in the serum, and reduced glutathione (GSH), and thiobarbituric acid reactive species (TBARs) levels in the hepatic tissue.

RESULTS

HPLC-ESIMS analysis of the SPOE fraction tentatively identified 35 flavonoids, esters of hydroxycinnamic acid and isomers of chlorogenic acid. SPAE (600 and 1200 mg/kg bw) and SPOE (300 mg/kg bw) antagonized the rise in ALT and AST, and the depletion of GSH, and elevation of TBARs levels in the liver caused by AP. The liver protective effects of SPOE (300 mg/kg bw) against AP-induced liver toxicity mimicked those of N-acetyl-cysteine (NAC 300 or 600 mg/kg bw ip). The mouse writhing assay showed that SPOE (300 mg/kg bw po) has anti-nociceptive effects comparable to those of AP (180 mg/kg bw po).

CONCLUSION

This study suggests that an extract of S. paniculatum leaves (SPOE), rich in phenolic compounds, is a promising herbal drug to prevent and treat AP poisoning and presents analgesic properties as well.

Phytochemical Composition of Solanum retroflexum Analysed with the Aid of Ultra-Performance Liquid Chromatography Hyphenated to Quadrupole-Time-of-Flight Mass Spectrometry (UPLC-qTOF-MS)

Solanum retroflexum (nightshade) is an edible plant that is consumed in some regions of South Africa. Its leaves are a good source of vitamins, proteins, and minerals. It appears that there is no scientific report about the phytochemical composition of S. retroflexum. Here, ultra-performance liquid chromatography coupled to quadruple-time-of-flight mass spectrometry (UPLC-qTOF-MS) technique was use to achieve an untargeted metabolite fingerprinting of this plant. A total of 30 phytochemicals, including alkaloids, flavonoids, and cinnamic acids derivatives, were identified from the methanolic leaf extracts. The concentration of solvent did not affect the type of compounds extracted. The extraction resulted in qualitative yields of molecules such as quercetin-3-rutinoside, kaempferol-3-0-rutinoside, kaempferol-3-0-glucoside, 3-caffeoylquinic acid, 5-caffeoylquinic acid, and 3, 4-di-caffeoylquinic acid. The present study confirms the presence of phytochemical compounds in S. retroflexum similar to other Solanum plants.

Comprehensive metabolite profiling of Solanum tuberosum L. (potato) leaves by HPLC-ESI-QTOF-MS

The objective of this work was to study the non-targeted metabolite profiling of potato leaves using high performance liquid chromatography coupled to quadrupole-time of flight mass spectrometry (HPLC-ESI-QTOF-MS). The mass accuracy, true isotopic pattern in both MS and MS/MS spectra provided by QTOF-MS made possible the tentative identification of 109 compounds present in potato leaves, including organic acids, amino acids and derivatives, phenolic acids, flavonoids, iridoids, oxylipins and other polar and semi-polar compounds. Among them, 32 compounds have been found for the first time in potato leaf and in the Solanaceae family. Quinic acid and its derivatives represented more than 45% of the bioactive compounds quantified in the extract. Derivatives of hydroxybenzoic acid and gentisic acid were also founded at considerable concentrations. This study shed light on the composition of potato leaf extract and will serve as a base for further research into activities of the various compounds found in this matrix which has demonstrated a potential use as functional ingredients.

A Multi-Omics Analysis of Glycine max Leaves Reveals Alteration in Flavonoid and Isoflavonoid Metabolism Upon Ethylene and Abscisic Acid Treatment

Phytohormones are central to plant growth and development. Despite the advancement in our knowledge of hormone signaling, downstream targets, and their interactions upon hormones action remain largely fragmented, especially at the protein and metabolite levels. With an aim to get new insight into the effects of two hormones, ethylene (ET) and abscisic acid (ABA), this study utilizes an integrated proteomics and metabolomics approach to investigate their individual and combined (ABA+ET) signaling in soybean leaves. Targeting low-abundance proteins, our previously established protamine sulfate precipitation method was applied, followed by label-free quantification of identified proteins. A total of 4129 unique protein groups including 1083 differentially modulated in one (individual) or other (combined) treatments were discerned. Functional annotation of the identified proteins showed an increased abundance of proteins related to the flavonoid and isoflavonoid biosynthesis and MAPK signaling pathway in response to ET treatment. HPLC analysis showed an accumulation of isoflavones (genistin, daidzein, and genistein) upon ET treatment, in agreement with the proteomics results. A metabolome analysis assigned 79 metabolites and further confirmed the accumulation of flavonoids and isoflavonoids in response to ET. A potential cross-talk between ET and MAPK signaling, leading to the accumulation of flavonoids and isoflavonoids in soybean leaves is suggested.

Jackfruit (Artocarpus heterophyllus Lam.) peel: A better source of antioxidants and a-glucosidase inhibitors than pulp, flake and seed, and phytochemical profile by HPLC-QTOF-MS/MS

Jackfruit (Artocarpus heterophyllus Lam.) peel is an underutilized by-product in both, the production and processing of jackfruit. This research compared the antioxidant and hypoglycemic potential of jackfruit peel with jackfruit pulp, flake and seed for the first time. The phytochemical profile of peel extract was characterized with HPLC-QTOF-MS/MS. Results revealed that peel extract exhibited the highest total phenolic and total flavonoid content, and the phenolics was 4.65, 4.12 and 4.95 times higher than that of pulp, flake and seed extract, respectively. The strongest DPPH and ABTS⁺ scavenging ability, α-glucosidase inhibition were also found in peel extract, and the α-glucosidase inhibition was about 11.8-fold of that of acarbose. The HPLC-QTOF-MS/MS analysis led to the tentative identification of 53 compounds, prenylflavonoids, hydroxycinnamic acids and glycosides are the predominant bioactive compounds. Above results reveal promising potential of jackfruit peel as a new source of natural antioxidants and hypoglycemic agents.