Search Results (10)

Research on lemon grass (Cymbopogon citratus L.) revealed a variety of active molecules and examined their biological characteristics. However, most of these studies were conducted on wild varieties, while cultivated plants were addressed less. This study aimed to characterize the biomolecules and biological activities of lemon grass growing under North African conditions in Morocco. Phenolic compound profiles of aqueous (AE), ethanol (EE), and methanol (ME) extracts and their fractions were obtained with steric exclusion chromatography on Sephadex G50 gel and identified by LC-MS/MS. Then, total polyphenols (TPC), flavonoids (TFC), and antioxidant activities (FRAP: scavenging value and TAC: Total Antioxidant Capacity) of the fraction were evaluated, as well as the antimicrobial activity. The obtained results showed that the ME contained eight major compounds (i.e., apigenine-7-O-rutinoside and myricitine-3-O-rutinoside). The AE showed the presence of five molecules (i.e., kaempferol-3-O-glucuronide), while EE showed the presence of three molecules (i.e., quercetine-3-O-rutinoside). Regarding the chemical characterization, the highest value of total phenolic content (TPC) was obtained in AE (25) (4.60 ± 0.29 mg/g), and the highest value of total flavonoid content (TFC) was obtained in ME (29) (0.7 ± 0.08 mg/g). Concerning the antioxidant activity, the highest FRAP was obtained in ME (29) (97.89%), and the highest total antioxidant capacity (TAC) was obtained in ME (29) (89.89%). Correlation between FRAP, TPC, and TFC was noted only in fractions of AE and ME. All tested extracts of C. citratus and their fractions showed a significant antimicrobial effect. The lowest minimum inhibitory concentration (MIC) was recorded for ME against E. coli. Extracts’ biological activities and their fractions were governed by their active molecules. These data are new and clarify a novel aspect of bioactive molecules in the extracts of cultivated C. citratus. Equally, throughout this research, we clarified the relationship between identified molecules and their biological properties, including antioxidant and anti-microbial activities, which is new for the study area. This study is suggested as a reference for comparative studies and other assays of other biological activities for the study plant. Full article

A set of 54 snap bean lines grown under organic farming was characterized for different traits: pod color, pod cross-section shape, pod section width (PSW), protein content (PC), and sugar content (S). After cooking, the lines were analyzed for firmness and color parameters (CIE-L*, a*, b*). The snap bean lines were grouped based on pod cross-section shape and pod color into eight groups, and significant differences were observed among lines and groups for all the traits investigated. In particular, the yellow pods were harder than the other snap beans and less sweet due to the negative correlation between firmness and sugar content. Fourteen selected lines with contrasting firmness and belonging to different color groups were investigated for their phenolic composition and antioxidant activity (TEAC) before and after domestic cooking. A general decrease was observed only for vanillic acid, quercetin, and apigenin-8-C-glucoside. Quercetin-3-O-rutinoside and kaempferol-3-O-rutinoside were detected in all samples with the highest values in the SBP042 line in both raw and cooked samples. Antioxidant activity decreased with cooking (average of 39%), but purple line SBP053 showed the lowest and no significant loss (3.1%). The results reported in this study could be useful to design specific varieties for different markets and purposes. Full article

Fermented Capsicum frutescens L. is a well-known traditional food ingredient in China with a variety of potential nutritional functions due to the increased content of polyphenolic compounds during the fermentation process. This study aimed to investigate the ameliorative effect of fermented chili peppers (FCP) on insulin resistance and the potential mechanism of action. HepG2 cells were treated with 5 × 10⁻⁶ mol/L insulin for 12 h to establish the insulin resistance model. The results showed that the ethanol extract of FCP (1 mg/mL), rather than non-FCP extract, significantly increased glucose consumption in insulin-resistant HepG2 cells, which was at least partly attributed to an increase in polyphenolic compounds after fermentation, including kaempferol-3-O-rutinoside, caffeic acid, kaempferol-3-O-glucoside, luteolin, and apigenin. Molecular docking analysis suggested that these five significantly increased polyphenolic compounds in FCP could partially and effectively interact with the key amino acid residues of four key insulin resistance-related receptors (INSR, PTP1B, PPAR-γ, and AMPK). In conclusion, the fermentation process enhanced or even conferred a pronounced anti-insulin resistance effect on chili peppers, and the increased polyphenolic compounds in chili pepper had synergistic effects in modulating the INSR, PTP1B, PPAR-γ, and AMPK pathways to regulate the destruction of glucose consumption. Full article

As an emerging third-generation fruit, blackberry has high nutritional value and is rich in polyphenols, flavonoids and anthocyanins. Flavonoid biosynthesis and metabolism is a popular research topic, but no related details have been reported for blackberry. Based on previous transcriptome data from this research group, two blackberry flavonol synthase genes were identified in this study, and the encoded proteins were subjected to bioinformatics analysis. RuFLS1 and RuFLS2 are both hydrophobic acidic proteins belonging to the 2OG-Fe(II) dioxygenase superfamily. RuFLS2 was expressed at 27.93-fold higher levels than RuFLS1 in red–purple fruit by RNA-seq analysis. Therefore, RuFLS2-overexpressing tobacco was selected for functional exploration. The identification of metabolites from transgenic tobacco showed significantly increased contents of flavonoids, such as apigenin 7-glucoside, kaempferol 3-O-rutinoside, astragalin, and quercitrin. The high expression of RuFLS2 also upregulated the expression levels of NtF3H and NtFLS in transgenic tobacco. The results indicate that RuFLS2 is an important functional gene regulating flavonoid biosynthesis and provides an important reference for revealing the molecular mechanism of flavonoid accumulation in blackberry fruit. Full article

Annona crassiflora Mart., the marolo fruit of the Cerrado biome, is one of the most frequently consumed species from the Brazilian Midwest. This study aimed to evaluate the chemical composition and the antioxidant and cytotoxic properties of the fruit pulp of A. crassiflora collected at Chapada das Mesas, Maranhão, Brazil. The volatile concentrate was identified as mainly ethyl octanoate, ethyl hexanoate, and methyl octanoate. From the ethanol (LFP-E) and ethyl acetate (LFP-A) extracts were identified phenolic acids (p-coumaric, gallic, quinic, and ferulic), flavones and derivatives (apigenin, epicatechin, 2′-5-dimethoxyflavone, 3′,7-dimethoxy-3-hydroxyflavone, kaempferol-3-O-glucoside and 3-O-rutinoside, quercetin-3-O-glucoside, procyanidin B2, and rutin), aporphine alkaloids (xylopine, stephagine, and romucosine), and acetogenin (annonacin). For the LFP-E and LFP-A extracts, the total phenolic compound values were 15.89 and 33.16 mg GAE/g, the flavonoid compound content values were 2.53 and 70.55 mg QE/g, the DPPH radical scavenging activity showed EC₅₀ values of 182.54 and 57.80 µg/mL, and the ABTS radical activity showed TEAC values of 94.66 and 192.61 µM TE/g. The LFP-E extract showed significant cytotoxicity and cell selectivity for the U251-glioma strain, presenting a GI₅₀ value of 21.34 µg/mL, which is close to doxorubicin (11.68 µg/mL), the standard chemotherapeutic drug. The marolo fruit seems to be a promising source for developing innovative and healthy products for the food industry. Full article

Tulipa gesneriana has rich cultivars with abundant flower colors; among them, black tulips have become precious cultivars for their rareness in nature. It is of great significance to understand its color formation mechanism for breeding new cultivars with a blackish flower color in the future. In this present study, petals at five developmental stages of Tulipa gesneriana ‘Queen of Night’ (shorted for ‘QN’), a typical black tulip cultivar, were collected to identity the flavonoid composition and compare the accumulation along with the flower development process, aiming to explore the metabolic mechanism of its flower coloration. By using UPLC-Q-TOF-MS, three anthocyanins and nineteen anthoxanthins (including eighteen flavonols and one flavone) were detected in the petals of ‘QN’. The anthocyanins were identified as delphinidin 3-o-rutinoside, cyanidin 3-o-rutinoside and pelargonidin 3-o-rutinoside, respectively. The main flavonols were identified as quercetin, kaempferol, isorhamnetin, naringin and their glycosides. The only one flavone substance was identified as an apigenin derivative. By comparing the content, anthocyanins were the most abundant substance in the petals of ‘QN’, and showed obvious regularity in the development process. With the flower opening, the anthocyanin content accumulated continuously, and reached the highest level at 3575.9 μg·g⁻¹·FW at S5, accounting for 80% of the total flavonoids. Among them, delphinidin 3-o-rutinoside and cyanidin 3-o-rutinoside made the main contribution to the coloration of ‘QN’. The content of anthoxanthins increased first and then decreased, reaching the highest to 1114.8 μg·g⁻¹·FW at S3. Quercetin and its glycosides were the most important flavonol substances in the petals of ‘QN’, accounting for more than 60% of the total anthoxanthins in the five stages. The content of a flavone identified was extremely low, suggesting a limited role in the flower color of ‘QN’. Taken together, the flower color presentation of ‘QN’ was closely related to the composition and accumulation of anthocyanins and flavonols; anthocyanins were the main substances that determine the petal coloration of ‘QN’, and the high content of flavonols played a role of co-pigmentation with these anthocyanins. Full article

This study exploited the application of pulsed electric field (PEF) on the recovery of polyphenols from aerial parts of Sideritis scardica, tepals of Crocus sativus, and fruits of Vitis vinifera. Short pulses of 10 μs in a period of 1 ms were applied to the plant material, while different electric field intensities, 1.2 to 2.0 kV/cm were tested to optimize the procedure. The content in total polyphenols and the polyphenolic profile of the plant extracts were evaluated. Along with PEF samples, control samples were prepared for comparison. PEF treatment enhanced the recovery in total polyphenols for all the three plants examined. A significant increase was noticed in each plant tested and PEF condition applied, though lower electric field intensities up to 1.4 kV/cm proved to be more effective. Under the optimum electric field intensities, 1.4 kV/cm for V. vinifera and 1.2 kV/cm for S. scardica and C. sativus, increases of 49.15%, 35.25%, and 44.36% in total polyphenol content, respectively, were achieved. Additionally, an 85% increase of quercetin 3-rutinoside for V. vinifera, a 56% of apigenin 7-O-glucoside for S. scardica, and a 64% increase for kaempferol 3-O-glucoside for C. sativus were obtained. Full article

Many halophytes have great nutritional and functional potential, providing chemical compounds with biological properties. Salicornia patula Duval-Jouve is a common euhalophyte from saline Mediterranean territories (Spain, Portugal, France, and Italy). In the present work we quantified for the first time the bioactive compounds in S. patula (total phenolic compounds and fatty acids), from Iberian Peninsula localities: littoral-coastal Tinto River basin areas (southwest Spain, the Huelva province), and mainland continental territories (northwest and central Spain, the Valladolid and Madrid provinces). Five phenolic acids including caffeic, coumaric, veratric, salicylic, and transcinnamic have been found with differences between mainland and coastal saltmarshes. S. patula contain four flavonoids: quercetin-3-O-rutinoside, kaempferol/luteolin, apigenin 7-glucoside, and pelargonidin-3-O-rutinoside. These last two glycosylated compounds are described for the first time in this genus of Chenopodiaceae. The fatty acid profile described in S. patula stems contains palmitic, oleic, and linoleic acids in high concentrations, while stearic and long-chain fatty acids were detected in low amounts. These new findings confirm that S. patula is a valuable source of bioactive compounds from Mediterranean area. Full article

Background: Flavonoids with various structures play a vital role in plant acclimatization to varying environments as well as in plant growth, development, and reproduction. Exogenous applications of ethylene and 1-aminocyclopropane carboxylic acid (ACC), could affect the accumulation of flavonoids. Very few attempts have been made to investigate the effect of 1-aminocyclopropane carboxylic acid oxidase (ACO), a unique enzyme that catalyzes ACC to ethylene, on genes and metabolites in the flavonoid biosynthetic pathway. In this study, two ACOs in safflower (CtACOs) were cloned, and then transgenic safflower with overexpressed CtACO1 was generated through the Agrobacterium-mediated floral dipping method. Results: CtACO1 and CtACO2 were both characterized by the 2-oxoglutarate binding domain RxS and the ferrous iron binding site HxDxnH as ACOs from other plants. However, the transcript levels of CtACO1 in flowers at stages I, II, III, and IV were all higher than those of CtACO2. At the cellular level, by using electroporation transformation, CtACO1 was found to be localized at the cytomembrane in onion epidermal cells. CtACO1 overexpression had varying effects on genes involved in the ethylene and flavonoid biosynthetic pathways. The metabolites analysis showed that CtACO1 overexpression lines had a higher accumulation of quercetin and its glycosylated derivatives (quercetin 3-β-d-glucoside and rutin). In contrast, the accumulation of quinochalcones (hydroxysafflor yellow A and carthamin), kaempferol glycosylated derivatives (kaempferol-3-O-β-rutinoside and kaempferol-3-O-β-d-glucoside), apigenin, and luteolin in CtACO1 overexpression lines were decreased. Conclusion: This study confirmed the feasibility of applying the floral dipping method to safflower and showed a novel regulatory effect of CtACO1 in the flavonoid biosynthetic pathway. It provides hypothetical and practical groundwork for further research on regulating the overall metabolic flux of flavonoids in safflower, particularly hydroxysafflor yellow A and other quinochalcones, by using appropriate genetic engineering strategies. Full article

Full article