In vitro antileukaemic activity of extracts from berry plant leaves against sensitive and multidrug resistant HL60 cells

From by-products to new application opportunities: the enhancement of the leaves deriving from the fruit plants for new potential healthy products

In the last decades, the world population and demand for any kind of product have grown exponentially. The rhythm of production to satisfy the request of the population has become unsustainable and the concept of the linear economy, introduced after the Industrial Revolution, has been replaced by a new economic approach, the circular economy. In this new economic model, the concept of "the end of life" is substituted by the concept of restoration, providing a new life to many industrial wastes. Leaves are a by-product of several agricultural cultivations. In recent years, the scientific interest regarding leaf biochemical composition grew, recording that plant leaves may be considered an alternative source of bioactive substances. Plant leaves' main bioactive compounds are similar to those in fruits, i.e., phenolic acids and esters, flavonols, anthocyanins, and procyanidins. Bioactive compounds can positively influence human health; in fact, it is no coincidence that the leaves were used by our ancestors as a natural remedy for various pathological conditions. Therefore, leaves can be exploited to manufacture many products in food (e.g., being incorporated in food formulations as natural antioxidants, or used to create edible coatings or films for food packaging), cosmetic and pharmaceutical industries (e.g., promising ingredients in anti-aging cosmetics such as oils, serums, dermatological creams, bath gels, and other products). This review focuses on the leaves' main bioactive compounds and their beneficial health effects, indicating their applications until today to enhance them as a harvesting by-product and highlight their possible reuse for new potential healthy products.

Strawberry Fragaria x ananassa cv. Festival: A Polyphenol-Based Phytochemical Characterization in Fruit and Leaf Extracts

Berry fruits are an important dietary source of health-promoting antioxidant polyphenols. Interestingly, berry leaves of diverse species, including strawberries, have shown higher bioactive phytochemical content in the leaves than in the fruit. Moreover, the vegetative part of the plants is usually discarded, representing a presumably large source of underutilized bioactive biomass. In this investigation, the polyphenol profiles of tropical highland strawberry (Fragaria x ananassa cv. Festival) leaves and fruits were compared by high-performance liquid chromatography coupled with a diode array detector (UHPLC-DAD) and mass spectrometry (HPLC-MS). The total polyphenol strawberry leaf extracts exhibited a 122-fold-higher total polyphenol content and 13-fold higher antioxidant activity (ORAC) than strawberry fruits, and they showed evidence of possible photoprotective effects against UV damage in human melanoma cells (SK-MEL-28) and in murine embryo fibroblasts (NIH/3T3), together with promising anti-proliferative activities against the same melanoma cells. Seven polyphenols were confirmed by HPLC-DAD in the leaf extracts, with differences depending on fraction solubility. Moreover, three substituted quercetin derivatives, three substituted kaempferol derivatives, two anthocyanins, and catechin were confirmed in the soluble fraction by HPLC-MS. Given their higher total polyphenol content and bioactive activities, underutilized strawberry Festival leaves are a potential source of apparently abundant biomass with prospective bioactive applications.

Nanoencapsulation of Vaccinium ashei Leaf Extract in Eudragit® RS100-Based Nanoparticles Increases Its In Vitro Antioxidant and In Vivo Antidepressant-like Actions

Depression is a major psychiatric disorder in Brazil and worldwide. Vaccinium ashei (V. ashei) leaves are cultivation by-products with high bioactive compound levels. Here, a hydroalcoholic extract of V. ashei leaves (HEV) was associated with Eudragit^® RS100-based nanoparticles (NPHEV) to evaluate the in vitro antioxidant and in vivo antidepressant-like effects. Interfacial deposition of the preformed polymer method was used for NPHEV production. The formulations were evaluated regarding physicochemical characteristics, antioxidant activity (DPPH radical scavenging and oxygen radical absorbance capacity), and antidepressant-like action (1-25 mg/kg, single intragastric administration) assessed in forced swimming and tail suspension tests in male Balb-C mice. The NPHEV presented sizes in the nanometric range (144-206 nm), positive zeta potential values (8-15 mV), polydispersity index below 0.2, and pH in the acid range. The phenolic compound content was near the theoretical values, although the rutin presented higher encapsulation efficiency (~95%) than the chlorogenic acid (~60%). The nanoencapsulation improved the HEV antioxidant effect and antidepressant-like action by reducing the immobility time in both behavioral tests. Hence, Eudragit^® RS100 nanoparticles containing HEV were successfully obtained and are a promising alternative to manage depression.

Hydroalcoholic Extract of Rabbiteye Blueberry (Vaccinium ashei) Leaves Mitigates Unpredictable Chronic Mild Stress Model Inducing Depressive-Like Behavior in Rats

Several studies reported that rabbiteye blueberry (Vaccinium ashei Reade) leaves present promising biological properties. To the best of our knowledge, no study investigated the possible application of their hydroalcoholic extract for treating mood disorders. Herein, we evaluated if the hydroalcoholic extract of rabbiteye blueberry (Vaccinium ashei Reade) leaves (HEV) promotes an antidepressant-like effect in rodents using chronic experimental approaches. The effect of repeated administration of HEV (50 mg/kg, p.o.) on the immobility time was assessed in the forced swimming test (FST) in an unpredictable chronic mild stress (UCMS) model. Repeated treatment with HEV reversed the depressive-like behavior induced by UCMS by reducing the immobility time. Besides, the exposure to HEV caused no changes in relative organ weights in rats submitted to UCMS. The results indicated that HEV administration presented antidepressant-like action devoid of toxic effects. Thus, it is possible to suggest its potential as a safe and accessible therapeutic tool in the management of depression and other related mood disorders.

Effect of Blueberry Extract on Liver in Aged Rats

Aging and age-related disorders are prominent issues. Aging is associated with a gradual impairment of physiology at the genetic, cellular, tissue, and whole organism level that directly influences the development of chronic diseases and organ failure. Blueberries, on the other hand, are well known for their high content of bioactive compounds and have demonstrated positive impacts on metabolic factors that influence health and general well-being. This study is aimed at evaluating the ameliorating the effects of blueberry on the liver of aged rats by monitoring changes in metabolic disturbances, oxidative stress, and inflammatory disruption. The aged group of rats was orally administered with blueberry extract (200 mg/kg) for a period of 4 weeks. The results revealed that aging was associated with an increase in body weight, liver weight, and metabolic parameters like serum insulin, triglycerides, total cholesterol, and liver function markers accompanied with a decrease in vitamin D levels. Furthermore, the results showed a significant diminish in the activities of antioxidant enzymes, glutathione content with an elevation in lipid peroxidation, inflammatory mediators (tumor necrosis factor alpha, interleukin 6, and nuclear factor kappa-light-chain-enhancer of activated B cells) as well as fibrotic markers (TGF-β1) in the liver of aged rats. Compared to the young rats (control group), blueberry effectively reversed age-mediated disruption of the aforementioned parameters. Hence, blueberries can be used as a potential therapeutic strategy for the management of age-related liver dysfunction and disease.

In Vitro Antioxidant and Prooxidant Activities of Red Raspberry (Rubus idaeus L.) Stem Extracts

Leaves and stems of red raspberry (Rubus idaeus) are used in Lithuanian folk medicine. Healing properties of raspberry are related to the content of bioactive compounds, mainly polyphenols. Extracts of raspberry leaves contained higher total phenolic content (TPC) (1290 mg/L, expressed in gallic acid equivalent) compared to that in extracts of stems or peeled bark (up to 420 mg/L and 598 mg/L, respectively). To find out whether the collection time of herbal material was critical for the properties of the extracts, the stems were collected at different times of the year. TPC in the extracts depended more on extraction conditions rather than on the sampling time. Antioxidant activity of raspberry stem and bark extracts tested by spectrophotometric (DPPH● scavenging) and electrochemical (cyclic and differential pulse voltammetry) assays correlated with TPC. DPPH radical scavenging activity values for stem, leaf, and bark extracts were as follows: ≤1.18 ± 0.07, 1.63 ± 0.10, and ≤1.90 ± 0.04 (mmol/L, TROLOX equivalent), respectively. Assessed electrochemically, hydrogen peroxide-scavenging activity of extracts was independent on TPC. The latter activity was related to the presence of some protein in the extract as revealed by gel electrophoresis. Prooxidant activity of raspberry stem extracts was dependent on solution pH and temperature.

Phenolic Composition, Mineral Content, and Beneficial Bioactivities of Leaf Extracts from Black Currant (Ribes nigrum L.), Raspberry (Rubus idaeus), and Aronia (Aronia melanocarpa)

Currently, the incidence of lifestyle diseases is increasing due to inappropriate nutrition and environmental pollution. To prevent these diseases, various groups of bioactive compounds are needed with a broad spectrum of action and without adverse side effects. Polyphenolic compounds are the most widely studied group of this type of compounds. They occur widely in plants, but their content depends on many factors, including the type of plant, climatic conditions, and the date of harvest. The spectrum of bioactivity of phenolic compounds is determined by their chemical structure, concentration, and interaction with other compounds. Traditional recipes have been studied to search for active plant ingredients. Leaves of shrubs and fruit trees were used in folk medicine as a panacea for many diseases and have been forgotten with time, but their benefits are now being rediscovered. In recent years, much new information about biological activity of phenolic compounds from berry bushes (black currant, raspberry, and aronia) was published. This was reviewed and discussed in this article. The mineral content of their leaves was also summarized because minerals constitute a significant component of plant infusions. It has been shown that high antioxidant and biological activity of leaf extracts results from the presence of active phenolic compounds, which occur in definitely higher amounts than in fruits. Therefore, the leaves of berry bushes seem to be a promising source of substances that can be used as replacements for synthetic agents in the treatment and prevention of lifestyle diseases.

In Vitro Propagation and Variation of Antioxidant Properties in Micropropagated Vaccinium Berry Plants-A Review

The berry crops in genus Vacciniun L. are the richest sources of antioxidant metabolites which have high potential to reduce the incidence of several degenerative diseases. In vitro propagation or micropropagation has been attractive to researchers for its incredible potential for mass production of a selected genotype in a short time, all year round. Propagation techniques affect the antioxidant activity in fruits and leaves. Total antioxidant activity was higher in the fruit of in vitro propagated plants compare to the plants grown ex vivo. This review provides critical information for better understanding the micropropagation and conventional propagation methods, and their effects on antioxidant properties and morphological differentiation in Vaccinium species, and fills an existing gap in the literature.

Chemometric Characterization of Strawberries and Blueberries according to Their Phenolic Profile: Combined Effect of Cultivar and Cultivation System

Chemical characterizations of leaves and fruits that were obtained from organically and integrally produced strawberries ('Favette', 'Alba', and 'Clery') and blueberries ('Bluecrop', 'Duke', and 'Nui') from western Serbia were undertaken in this study. Phenolic analysis was done while using ultra-high performance liquid chromatography coupled to a linear ion trap-Orbitrap hybrid mass analyzer, while total phenolic content (TPC), total anthocyanin content (TAC), and radical-scavenging activity (RSA) by spectrophotometry. In general, leaves and fruits from blueberry showed higher levels of TPC and TAC as compared to strawberry. These chemical traits were larger in organic grown fruits and larger in leaves than fruits. The most abundant phenolics in leaves and fruits of blueberry was 5-O-caffeoylquinic acid, followed by quercetin 3-O-galactoside, while catechin, quercetin, and kaempferol 3-O-glucosid were dominant in the leaves and fruits of strawberry. cis, trans-Abscisic acid was detected in all fruit samples, but not in leaves. Blueberries (both fruits and leaves) were separated from strawberries, but only organic blueberry fruits were distinguished from integrated fruits, according to principal component analysis. Quercetin, kaempferol, 5-O-caffeoylquinic acid, ferulic acid, caffeic acid, catechin, p-coumaric acid, and p-hydroxybenzoic acid were the most influential phenolic compounds for the separation. Much higher contents of TPC, RSA, TAC, quercetin 3-O-galactoside, and quercetin were found in fruits and TPC, RSA, catechin, p-hydroxybenzoicacid, p-coumaricacid, and ferulic acid in leaves in all three blueberry cultivars and the strawberry cultivar 'Clery'. These phenolic compounds are good sources of antioxidant compounds with potentially high beneficial effects on human health.

Antitumour effects of selected plant polyphenols, gallic acid and ellagic acid, on sensitive and multidrug-resistant leukaemia HL60 cells

The aim of this study was to examine the antitumour effects of plant phenolic acids, gallic acid (GA) and ellagic acid (EA), on human promyelocytic leukaemia sensitive HL60 cell line and its resistant sublines exhibiting two MDR phenotypes: HL60/VINC (overexpressing P-glycoprotein) and HL60/MX2 (characterized by the presence of mutated α isoform of topoisomerase II). Both studied compounds exerted comparable cytotoxic activities towards sensitive HL60 cells and their MDR counterparts. It was also found that GA and EA modulated the cellular level of reactive oxygen species in a dose-dependent and time-dependent manner. Furthermore, it was demonstrated that GA (IC₉₀ ) and EA (IC₅₀ and IC₉₀ ) significantly increased the percentage of sub-G1 subpopulation of all studied leukaemia cells causing oligonucleosomal DNA fragmentation. Both compounds used at IC₉₀ triggered mainly the apoptotic death of these cells. However, GA had no effect on the activity of caspase-3 as well as caspase-8 in sensitive HL60 cells and their MDR counterparts. In contrast, EA provoked a significant activation of these caspases in all studied leukaemia cells. It was also found that lysosomes were not involved in triggering programmed death of sensitive HL60 and MDR cells by GA and EA.

Influence of Harvest Season and Cultivar on the Variation of Phenolic Compounds Composition and Antioxidant Properties in Vaccinium ashei Leaves

The effect of variation of harvest season and cultivar on the total phenolic content (TPC), total flavonoid content (TFC), HPLC-UV/DAD profile and antioxidant properties in Vaccinium ashei (Rabbiteye blueberry) leaves grown in Brazil was evaluated. The cultivars collected in December and March were Aliceblue, Powderblue, Climax, Bluegem and FloridaM. It was observed that leaves from March had the highest TPC values (222 ± 1 mg gallic acid equivalents/g to Aliceblue cultivar) and highest TFC values (49.8 ± 0.8 and 48.7 ± 0.7 µg rutin/g to Clímax and Powderblue cultivars, respectively). The chromatographic profile was quantitatively similar, however, the proportions of each compound were influenced by cultivar and harvest season. Chlorogenic acid and rutin were the main identified phenolic compounds, but chlorogenic acid was the most abundant in both harvest seasons. Antioxidant capacities values ranged from 5.80 ± 0.04 to 105 ± 2 µg/mL (DPPH) and 178 ± 5 to 431 ± 8 mmol Trolox/100 g (ORAC). The cultivar Bluegem by March had the highest values in both assays. The results indicate that the blueberry leaves from different cultivars and harvest seasons have different phenolic compounds content and different antioxidant capacities. In addition, the antioxidant properties demonstrated a high correlation with rutin content.

Polyphenols Beyond Barriers: A Glimpse into the Brain

BACKGROUND

Ageing can be simply defined as the process of becoming older, which is genetically determined but also environmentally modulated. With the continuous increase of life expectancy, quality of life during ageing has become one of the biggest challenges of developed countries. The quest for a healthy ageing has led to the extensive study of plant polyphenols with the aim to prevent age-associated deterioration and diseases, including neurodegenerative diseases. The world of polyphenols has fascinated researchers over the past decades, and in vitro, cell-based, animal and human studies have attempted to unravel the mechanisms behind dietary polyphenols neuroprotection.

METHODS

In this review, we compiled some of the extensive and ever-growing research in the field, highlighting some of the most recent trends in the area.

RESULTS

The main findings regarding polypolyphenols neuroprotective potential performed using in vitro, cellular and animal studies, as well as human trials are covered in this review. Concepts like bioavailability, polyphenols biotransformation, transport of dietary polyphenols across barriers, including the blood-brain barrier, are here explored.

CONCLUSION

The diversity and holistic properties of polypolyphenol present them as an attractive alternative for the treatment of multifactorial diseases, where a multitude of cellular pathways are disrupted. The underlying mechanisms of polypolyphenols for nutrition or therapeutic applications must be further consolidated, however there is strong evidence of their beneficial impact on brain function during ageing. Nevertheless, only the tip of the iceberg of nutritional and pharmacological potential of dietary polyphenols is hitherto understood and further research needs to be done to fill the gaps in pursuing a healthy ageing.

Chemical Characterization and Cytotoxic Activity of Blueberry Extracts (cv. Misty) Cultivated in Brazil

Vaccinium corymbosum (L.) varieties cultivation is relatively recent in Brazil, but its production has been intensified given its good adaptability to the Southern Brazil climate. Blueberries are a rich source of phenolic compounds and contain significant levels of anthocyanins, flavonols, chlorogenic acids, and procyanidins, which lead to different biological activities. Chemical identification of skin and whole hydroalcoholic blueberry extracts (ExtSB and ExtWB) revealed the presence of anthocyanins concentrated in the skin and others chemicals compounds as quercetin glycosides, proanthocyanins dimers, citric, and chlorogenic acid in the pulp. Selectivity for tumor cell lines (Hep-2, HeLa, HT-29) using ExtSB and ExtWB extracts was observed through MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay after 24 h of treatment when compared to nontumor cells (MRC-5). Morphological changes and late stages of apoptotic and necrosis process were seen in HT-29 cell line after ExtWB treatment, compared to nontumor cell line MRC-5. These results are in agreement with other studies that indicate the activity of compounds such as anthocyanins and other molecules found in Southern Highbush blueberry variety, attributed to promote beneficial effects on health that may respond as cytotoxic natural agent and contribute to cancer treatment.

Anticancer and multidrug-resistance reversing potential of traditional medicinal plants and their bioactive compounds in leukemia cell lines

Multidrug resistance remains a serious clinical problem in the successful therapy of malignant diseases. It occurs in cultured tumor cell lines, as well as in human cancers. Therefore, it is critical to develop novel anticancer drugs with multidrug-resistance modulating potential to increase the survival rate of leukemia patients. Plant-derived natural products have been used for the treatment of various diseases for thousands of years. This review summarizes the anticancer and multidrug-resistance reversing properties of the extracts and bioactive compounds from traditional medicinal plants in different leukemia cell lines. Further mechanistic studies will pave the road to establish the anticancer potential of plant-derived natural compounds.

Cytotoxicity of dietary flavonoids on different human cancer types

Flavonoids are ubiquitous in nature. They are also in food, providing an essential link between diet and prevention of chronic diseases including cancer. Anticancer effects of these polyphenols depend on several factors: Their chemical structure and concentration, and also on the type of cancer. Malignant cells from different tissues reveal somewhat different sensitivity toward flavonoids and, therefore, the preferences of the most common dietary flavonoids to various human cancer types are analyzed in this review. While luteolin and kaempferol can be considered as promising candidate agents for treatment of gastric and ovarian cancers, respectively, apigenin, chrysin, and luteolin have good perspectives as potent antitumor agents for cervical cancer; cells from main sites of flavonoid metabolism (colon and liver) reveal rather large fluctuations in anticancer activity probably due to exposure to various metabolites with different activities. Anticancer effect of flavonoids toward blood cancer cells depend on their myeloid, lymphoid, or erythroid origin; cytotoxic effects of flavonoids on breast and prostate cancer cells are highly related to the expression of hormone receptors. Different flavonoids are often preferentially present in certain food items, and knowledge about the malignant tissue-specific anticancer effects of flavonoids could be purposely applied both in chemoprevention as well as in cancer treatment.

Estonian folk traditional experiences on natural anticancer remedies: from past to the future

CONTEXT

Despite diagnostic and therapeutic advancements, the burden of cancer is still increasing worldwide. Toxicity of current chemotherapeutics to normal cells and their resistance to tumor cells highlights the urgent need for new drugs with minimal adverse side effects. The use of natural anticancer agents has entered into the area of cancer research and increased efforts are being made to isolate bioactive products from medicinal plants.

OBJECTIVE

To lead the search for plants with potential cytotoxic activity, ethnopharmacological knowledge can give a great contribution. Therefore, the attention of this review is devoted to the natural remedies traditionally used for the cancer treatment by Estonian people over a period of almost 150 years.

METHODS

Two massive databases, the first one stored in the Estonian Folklore Archives and the second one in the electronic database HERBA ( http://herba.folklore.ee/ ), containing altogether more than 30 000 ethnomedicinal texts were systematically reviewed to compile data about the Estonian folk traditional experiences on natural anticancer remedies.

RESULTS AND CONCLUSION

As a result, 44 different plants with potential anticancer properties were elicited, 5 of which [Angelica sylvestris L. (Apiaceae), Anthemis tinctoria L. (Asteraceae), Pinus sylvestris L. (Pinaceae), Sorbus aucuparia L. (Rosaceae), and Prunus padus L. (Rosaceae)] have not been previously described with respect to their tumoricidal activities in the scientific literature, suggesting thus the potential herbal materials for further investigations of natural anticancer compounds.

Anti-Inflammatory and Anti-Superbacterial Properties of Sulforaphane from Shepherd's Purse

Shepherd's purse, Capsella bursa-pastoris (L.) Medik., has been considered a health food for centuries in Asia and is known to contain the isothiocyanate compound sulforaphane. In this study, we evaluated the anti-inflammatory and antibacterial properties of a sulforaphane-containing solution (SCS) isolated from shepherd's purse. SCS had significant anti-inflammatory activity indicated by the decreased levels of nitric oxide (NO), cytokines (interleukin 1β [IL-1β], IL-6, and IL-10), and prostaglandin E₂ (PGE₂) in lipopolysaccharide-stimulated RAW 264.7 murine macrophages. In addition, SCS decreased the inducible NO synthase (iNOS) and cyclooxygenase 2 (COX-2) levels, which confirmed the anti-inflammatory activity of SCS. Further, SCS inhibited vancomycin-resistant enterococci (VRE) and Bacillus anthracis. The minimal inhibitory concentration was 250 µg/ml for VRE and 1,000 µg/ml for B. anthracis. Taken together, these data indicate that SCS has potential anti-inflammatory and anti-superbacterial properties, and thus it can be used as a functional food or pharmaceutical.

Site-specific anticancer effects of dietary flavonoid quercetin

Food-derived flavonoid quercetin, widely distributed in onions, apples, and tea, is able to inhibit growth of various cancer cells indicating that this compound can be considered as a good candidate for anticancer therapy. Although the exact mechanism of this action is not thoroughly understood, behaving as antioxidant and/or prooxidant as well as modulating different intracellular signalling cascades may all play a certain role. Such inhibitory activity of quercetin has been shown to depend first of all on cell lines and cancer types; however, no comprehensive site-specific analysis of this effect has been published. In this review article, cytotoxicity constants of quercetin measured in various human malignant cell lines of different origin were compiled from literature and a clear cancer selective action was demonstrated. The most sensitive malignant sites for quercetin revealed to be cancers of blood, brain, lung, uterine, and salivary gland as well as melanoma whereas cytotoxic activity was higher in more aggressive cells compared to the slowly growing cells showing that the most harmful cells for the organism are probably targeted. More research is needed to overcome the issues of poor water solubility and relatively low bioavailability of quercetin as the major obstacles limiting its clinical use.

Natural product based leads to fight against leishmaniasis

The growing incidence of parasitic resistance against generic pentavalent antimonials, specifically for visceral disease in Indian subcontinent, is a serious issue in Leishmania control. Notwithstanding the two treatment alternatives, that is amphotericin B and miltefosine are being effectively used but their high cost and therapeutic complications limit their use in endemic areas. In the absence of a vaccine candidate, identification, and characterization of novel drugs and targets is a major requirement of leishmanial research. This review describes current drug regimens, putative drug targets, numerous natural products that have shown promising antileishmanial activity alongwith some key issues and strategies for future research to control leishmaniasis worldwide.

Influence of harvest season on antioxidant activity and constituents of rabbiteye blueberry ( Vaccinium ashei ) leaves

To select rabbiteye blueberry leaves from an appropriate harvest season to develop functional foods, this paper studied the bioactive secondary metabolites and the antioxidant capacity of rabbiteye blueberry leaves from May, September, and November. The results showed the leaves from May had the highest content of total flavonoids (114.21 mg/g) and the leaves from November had the highest content of total polyphenols and proanthocyanidins (425.24 and 243.29 mg/g, respectively). It was further found that blueberry leaves from different seasons have similar bioactive constituents, but their contents are obviously different by HPLC. The rabbiteye blueberry leaves from November had the highest antioxidant capacity, which was well correlated with their highest proanthocyanidin content. The results clarify that the blueberry leaves from different seasons have different contents of bioactive secondary metabolites and different antioxidant activities, which implied that leaves from November should be selected first for utilization in functional foods.

Immature Rubus coreanus Shows a Free Radical-Scavenging Effect and Inhibits Cholesterol Synthesis and Secretion in Liver Cells

Rubus coreanus fruits have been employed as a traditional medicine for centuries in the Asia-Pacific region. Its pharmacological action differs according to the different extraction methods utilized and the degree of fruit ripening. In this study, we determined the cellular effect of different ethanol extracts of mature and immature Rubus coreanus fruits in human hepatic cell line, HepG2 cells. The antioxidant activity, effect on superoxide dismutase activity and cholesterol biosynthesis efficiency was also evaluated. Immature Rubus coreanus extract showed higher antioxidant capability, compared with that of its mature fractions. Cellular antioxidant proteins including HO-1, Cu/Zn-superoxide dismutase and catalase were highly expressed in the presence of Rubus coreanus. Cholesterol levels in HepG2 cells treated with the water fraction of immature Rubus coreanus were significantly reduced. This antihyperlipidaemic action of Rubus coreanus is a consequence of cholesterol biosynthesis and extracellular secretion in HepG2 cells. These results indicate that among different ethanol fraction of mature and immature Rubus coreanus fruit extracts, water extract of immature fruit extract shows higher antioxidant as well as higher antihyperlipidaemic action.

Identification and characterization of low molecular weight polyphenols in berry leaf extracts by HPLC-DAD and LC-ESI/MS

This paper reports the results of qualitative and quantitative analyses of low molecular weight phenolics from five berry leaf extract using HPLC-DAD and LC-ESI/MS. The identification of the black currant, raspberry, bilberry, honeysuckle, and strawberry leaf phytochemicals was based on the comparison of UV-vis absorption maxima (λ(max)) and mass spectral analysis. The peak identification in samples was also based on comparisons of the retention times (t(R)) of the isolated phytochemical standards. Knowledge of the precise phenolic profile of berry leaves may offer a scientific basis to put the underutilized berry leaves to good use as very cheap raw materials for polyphenol extract production. These studies indicated that these leaves can be used as a good and cheap source of bioactive constituents. These results suggest that berry leaves are a potential source of phenolics and have potential pro-healthy properties to contribute to human health.

Screening Antitumor Compounds Psoralen and Isopsoralen from Psoralea corylifolia L. Seeds

Psoralea corylifolia L. (Fabaceae) is a widely used medical plant in China. This study was designed to screen and identify bioactive compounds with anticancer activity from the seeds of Psoralea corylifolia L. One volatile fraction (fraction I) and three other fractions (fraction II, III, IV) from methanol extraction of P. corylifolia L. were obtained. Bioactivities of these fractions were evaluated by the cytotoxicity on KB, KBv200, K562, K562/ADM cancer cells with MTT assay. Major components in the active fraction were identified by HPLC/MS(n). Fraction IV significantly inhibits the growth of cancer cells in a dose-dependent manner. The IC(50) values were 21.6, 24.4, 10.0 and 26.9, respectively. Psoralen and isopsoralen, isolated from fraction IV, were subject to bioactive assay and presented a dose-dependent anticancer activity in four cancer cell lines (KB, KBv200, K562 and K562/ADM). The IC(50) values of psoralen were 88.1, 86.6, 24.4 and 62.6, which of isopsoralen were 61.9, 49.4, 49.6 and 72.0, respectively. Apoptosis of tumor cell significantly increased after treated with psoralen and isopsoralen. Induction of apoptotic activity was confirmed by flow cytometry after staining with Annexin V/PI. These results suggested psoralen and isopsoralen contribute to anticancer effect of P. corylifolia L.

Quercetin: a potential drug to reverse multidrug resistance

This review centers on recent findings with respect to modulating cancer multidrug resistance (MDR) with the well-known flavonoid quercetin. After a short introduction of quercetin, major in vitro and in vivo findings are summarized showing that quercetin is a MDR modulator and thus a potential chemosensitizer. Finally, we contemplate future prospects of modulating MDR in the clinic.

NMR and UPLC-qTOF-MS/MS characterisation of novel phenylethanol derivatives of phenylpropanoid glucosides from the leaves of strawberry (Fragaria x ananassa cv. Jonsok)

INTRODUCTION

Strawberry (Fragaria x ananassa) is rich in polyphenols, particularly anthocyanins, flavonols, condensed tannins and ellagic tannins. In addition to the fruits, the leaves of strawberry also contain a wide range of phenolic compound classes, but have not been investigated to the same extent as the fruit.

OBJECTIVE

To characterise a metabolite group present in the leaves of strawberry, that was not amenable for identification based on earlier information available in the literature.

METHODOLOGY

Methanolic extracts of strawberry leaves were analysed by UPLC-qTOF-MS/MS and iterative quantum mechanical NMR spectral analysis.

RESULTS

The structures of phenylethanol derivatives of phenylpropanoid glucosides Eutigoside A ( F4) and its two isomeric forms 2-(4-hydroxyphenyl)ethyl-[6-O-(Z)-coumaroyl]-beta-D-glucopyranoside (F6) and 4-(2-hydroxyethyl)phenyl-[6-O-(E)-coumaroyl]-beta-D-glucopyranoside (F1) were resolved by NMR and UPLC-qTOF-MS/MS. In addition, two other derivatives of phenylpropanoid glucosides similar to Eutigoside A but possessing different phenolic acid moieties, namely Grayanoside A ( F5) and 2-(4-hydroxyphenyl)ethyl-[6-O-(E)-caffeoyl]-beta-D-glucopyranoside (F14), were similarly identified. Also, accurate characteristic coupling constants for the subunits are reported and their usefulness in structural analysis is highlighted.

CONCLUSION

Chemical analysis of the leaves of strawberry (Fragaria x ananassa cv. Jonsok) resulted in the identification of a compound class, phenylethanol derivatives of phenylpropanoid glycosides, not previously found in strawberry.

Antiinflammatory activities of Rubus coreanus depend on the degree of fruit ripening

The dried unripe fruit of Rubus coreanus, which is well-known in Korea and referred to as 'Bok-bun-ja', has been employed as a traditional medicine for centuries. This crude drug is utilized in Korea for the management of impotence, spermatorrhea, enuresis, asthma and allergic diseases. The principal objective of the present study was to conduct a comparison of the antiinflammatory effects of ethanol extracts of the unripe (URCE), half-ripened (HRCE) and ripe fruits (RCE) of Rubus coreanus. URCE and HRCE were found to reduce the production of nitric oxide (NO) and prostaglandin E2 (PGE2) as well as pro-inflammatory cytokines, in lipopolysaccharide (LPS)-stimulated RAW264.7 murine macrophages. However, RCE exerted no inhibitory effects against the production of NO and IL-6. The results of the study show that the degree of fruit ripening of Rubus coreanus affects the production of inflammatory mediators such as NO, PGE2 and inflammatory cytokines.

Rubus - A Review of its Phytochemical and Pharmacological Profile

Species of the genus Rubus (family Rosaceae, sub-family Rosoideae, tribe Potentilleae) are widely distributed in the warmer temperate zones of the northern hemisphere. Rubus species have been known since ancient times for their curative properties, and have been used for the treatment of various ailments, such as wounds, diarrhea, colic pain, diabetes, inflammatory disorders, and as antimicrobial agents. However, their use has been based mainly on empirical findings. This contribution provides a comprehensive review of the work published on the phytochemistry and pharmacology of the Rubus species over the past few years, in order to obtain a better understanding of the biological significance of this large genus.

Therapeutic Potential and Chemical Composition of Plants from the Genus Rubus: A Mini Review of the Last 10 Years

Rubus species (Rosaceae) are appreciated for their fruits and their traditional therapeutic uses. Several experimental investigations indicate important biological effects of these plants, related to the presence of different classes of chemical substances, especially terpenoids and phenolic compounds. This work outlines the main biological properties and chemical constituents of the genus Rubus over the last 10 years, with particular emphasis on the plants that occur in Brazil.

Protective actions of Rubus coreanus ethanol extract on collagenous extracellular matrix in ultraviolet-B irradiation-induced human dermal fibroblasts

Solar ultraviolet (UV) irradiation leads to distinct changes in the skin connective tissues by degradation of collagen, which is a major structural component in the extracellular matrix. UV irradiation induces the production of matrix metalloproteinases (MMP) capable of attacking native fibrillar collagen and responsible for inhibiting the construction of collagenous extracellular matrix. In this study, we attempted to investigate the protective actions of Rubus coreanus ethanol extract (RCE) on the MMP production and the consequent procollagen/collagen degradation in UV-B-irradiated human dermal fibroblasts. The analytical data showed that Rubus coreanus ethanol extract was mostly comprised of cyanidin 3-rutinoside. Pre-treatment of fibroblasts with this extract inhibited UV-B-induced production of MMP-1, MMP-8 and MMP-13 in dose-dependent manners. In addition, Western blot analysis and immunocytochemical staining assay revealed that RCE markedly augmented the cellular levels of procollagen/collagen declined in UV-B-exposed dermal fibroblasts. These results demonstrate that RCE blocks UV-B-induced increase of the collagen degradation by inhibiting MMP production. Thus, RCE may act as an agent inhibiting excessive dermal collagen degradation leading to the skin photoaging.