Phenolic compositions and antioxidant capacities of Chinese wild mandarin (Citrus reticulata Blanco) fruits

Antioxidant effect of Kimchi supplemented with Jeju citrus concentrate and its antiobesity effect on 3T3-L1 adipocytes

Citrus is cultivated throughout Jeju Island and is thought to possess some medicinal properties. Citrus concentrate is the most extensively utilized form of citrus in the food industry. In this study, antioxidant and antiobesity effects of Kimchi supplemented with citrus concentrate were investigated. Prepared Kimchi was infused with 7% citrus concentrate (CK) and freeze-dried for analysis. Normal Kimchi (NK) without citrus concentrate was utilized as a control. Total phenol content (TPC), total flavonoid content (TFC), and antioxidant activities were examined. Cytotoxicity, intracellular triglycerides (TG), and total cholesterol (TC) levels in 3T3-L1 adipocytes were also measured. Additionally, the inhibitory effects on lipid accumulation were trialed by measuring the oil-red O (ORO)-stained cells. TPC, TFC, and antioxidant activities of CK were significantly higher than those of NK (p < .05). CK showed less cytotoxicity and attenuated the lipid accumulation at all concentrations by reducing TG and TC levels compared to NK. The inhibitory effect of CK on lipid accumulation was observed via reducing ORO-stained lipid droplets. Consequently, the antioxidant and antiobesity effects of CK were revealed in vitro. Furthermore, the addition of citrus may provide competitive price due to low production costs as well as health functionality.

Integrated therapy decreases the mortality of patients with polymyositis and dermatomyositis: A Taiwan-wide population-based retrospective study

ETHNOPHARMACOLOGICAL RELEVANCE

The issue of whether integrated treatment with conventional medicine (CM) and herbal medicine (HM) can reduce mortality in patients with polymyositis/dermatomyositis (PM/DM) had not been addressed.

AIM OF THE STUDY

In this study, we investigated the effect of integrated therapy on mortality in a retrospective PM/DM cohort in the Taiwan National Health Insurance Research Database (NHIRD).

MATERIALS AND METHODS

Patients with PM/DM were retrospectively enrolled from the PM/DM Registry of Catastrophic Illnesses cohort in the Taiwan NHIRD between 1997 and 2011. The patients were divided into an integrated medicine (IM) group that received CM and HM and a non-IM group that received CM alone. The Cox proportional hazards regression model and Kaplan-Meier method were used to evaluate the hazard ratio (HR) for mortality.

RESULTS

Three hundred and eighty-five of 2595 patients with newly diagnosed PM/DM had received IM and 99 had received non-IM. The adjusted HR for mortality was lower in the IM group than in the non-IM group (0.42, 95% confidence interval 0.26-0.68, p < 0.001). The adjusted HR for mortality was also lower in the IM group that had received CM plus HM than in the group that received CM alone (0.48, 95% confidence interval 0.28-0.84, p < 0.05). The core pattern of HM prescriptions integrated with methylprednisolone, methotrexate, azathioprine, or cyclophosphamide to decrease mortality included "San-Qi" (Panax notoginseng), "Bai-Ji" (Bletilla striata), "Chen-Pi" (Citrus reticulata), "Hou-Po" (Magnolia officinalis), and "Dan-Shan" (Salvia miltiorrhiza).

CONCLUSION

Integrated therapy has reduced mortality in patients with PM/DM in Taiwan. Further investigation of the clinical effects and pharmaceutical mechanism involved is needed.

SlMYB75, an MYB-type transcription factor, promotes anthocyanin accumulation and enhances volatile aroma production in tomato fruits

Genetic manipulation of genes to upregulate specific branches of metabolic pathways is a method that is commonly used to improve fruit quality. However, the use of a single gene to impact several metabolic pathways is difficult. Here, we show that overexpression of the single gene SlMYB75 (SlMYB75-OE) is effective at improving multiple fruit quality traits. In these engineered fruits, the anthocyanin content reached 1.86 mg g-1 fresh weight at the red-ripe stage, and these SlMYB75-OE tomatoes displayed a series of physiological changes, including delayed ripening and increased ethylene production. In addition to anthocyanin, the total contents of phenolics, flavonoids and soluble solids in SlMYB75-OE fruits were enhanced by 2.6, 4, and 1.2 times, respectively, compared to those of wild-type (WT) fruits. Interestingly, a number of aroma volatiles, such as aldehyde, phenylpropanoid-derived and terpene volatiles, were significantly increased in SlMYB75-OE fruits, with some terpene volatiles showing more than 10 times higher levels than those in WT fruits. Consistent with the metabolic assessment, transcriptomic profiling indicated that the genes involved in the ethylene signaling, phenylpropanoid and isoprenoid pathways were greatly upregulated in SlMYB75-OE fruits. Yeast one-hybrid and transactivation assays revealed that SlMYB75 is able to directly bind to the MYBPLANT and MYBPZM cis-regulatory elements and to activate the promoters of the LOXC, AADC2 and TPS genes. The identification of SlMYB75 as a key regulator of fruit quality attributes through the transcriptional regulation of downstream genes involved in several metabolic pathways opens new avenues towards engineering fruits with a higher sensory and nutritional quality.

Effects of cross-pollination by 'Murcott' tangor on the physicochemical properties, bioactive compounds and antioxidant capacities of 'Qicheng 52' navel orange

This study investigated the effects of cross-pollination by 'Murcott' tangor on the fruit quality of 'Qicheng52' navel orange, including the physicochemical properties, bioactive compounds and antioxidant capacities. There were no significant differences on the fruit weight, juice yield and pH value of juice between self- and cross-pollinated fruits. However, cross-pollination could significantly improve the fruit quality of 'Qicheng52' fruits by increasing the total soluble solid content from 11.12 ± 1.02 °Brix to 13.86 ± 1.17 °Brix. The results of high performance liquid chromatography analysis of three sugar components indicated that the increase of total sugar was mainly contributed by the increase of fructose and sucrose. Cross-pollination exhibited no effect on the flavonoids content, while the total phenolics content was increased from 210.09 ± 18.55 mg/L to 298.25 ± 29.10 mg/L, which contributed to the higher antioxidant capacity in the cross-pollination fruit juice.

Comprehensive Metabolomics Analysis of Mandarins ( Citrus reticulata) as a Tool for Variety, Rootstock, and Grove Discrimination

The metabolite profile responsible for the quality of mandarin fruit is influenced by preharvest factors including genotype, rootstock, grove location, etc. In this paper, mandarin varieties were discriminated using metabolomics. Additionally, effects on metabolic profiles due to grove location and rootstock differences were also investigated. Results revealed that mandarin varieties could be differentiated using the metabolite profile, while the compositions of flavonoids have the potential for variety differentiation. With regard to fruits of the same variety, grove location might determine the overall profile of metabolites, whereas rootstock possibly affected composition of secondary metabolites. Pathway enrichment analysis demonstrated that biosynthesis pathways of terpenoids and steroids involving limonene and linalool were highly influenced by variety diversity. Moreover, the flavonoid biosynthesis pathway, involving hesperetin, naringenin, eriodictyol, and taxifolin, was indicated to have a close relationship with rootstock differentiation. This study provides useful and important information with depth for breeding and optimizing preharvest practices.

A Comparative Metabolomics Analysis Reveals the Tissue-Specific Phenolic Profiling in Two Acanthopanax Species

Acanthopanax senticosus (Rupr. Maxim.) Harms (ASH) and Acanthopanax sessiliflorus (Rupr. Maxim.) Seem (ASS), are members of the Araliaceae family, and both are used in Asian countries. These herbals have drawn much attention in recent years due to their strong biological activity, with innocuity and little side effects. However, the common and distinct mode of compound profiles between ASH and ASS is still unclear. In this study, a high performance liquid chromatograph-mass spectrometry (HPLC-MS) method was developed to simultaneously quantify the seven major active compounds, including protocatechuate, eleutheroside B, eleutheroside E, isofraxidin, hyperoside, kaempferol and oleanolic acid. Then the targeted metabolomics were conducted to identify 19 phenolic compounds, with tight relation to the above mentioned active compounds, including nine C6C3C6-type, six C6C3-type and four C6C1-type in the two Acanthopanax species studied here. The results showed that the seven active compounds presented a similar trend of changes in different tissues, with more abundant accumulation in roots and stems for both plants. From the view of plant species, the ASH plants possess higher abundance of compounds, especially in the tissues of roots and stems. For phenolics, the 19 phenols detected here could be clearly grouped into five main clusters based on their tissue-specific accumulation patterns. Roots are the tissue for the most abundance of their accumulations. C6C3C6-type compounds are the most widely existing type in both plants. In conclusion, the tissue- and species-specificity in accumulation of seven active compounds and phenolics were revealed in two Acanthopanax species.

Genome of Wild Mandarin and Domestication History of Mandarin

Mandarin (Citrus reticulata) is one of the most important citrus crops worldwide. Its domestication is believed to have occurred in South China, which has been one of the centers of mandarin cultivation for four millennia. We collected natural wild populations of mandarin around the Nanling region and cultivated landraces in the vicinity. We found that the citric acid level was dramatically reduced in cultivated mandarins. To understand genetic basis of mandarin domestication, we de novo assembled a draft genome of wild mandarin and analyzed a set of 104 citrus genomes. We found that the Mangshan mandarin is a primitive type and that two independent domestication events have occurred, resulting in two groups of cultivated mandarins (MD1 and MD2) in the North and South Nanling Mountains, respectively. Two bottlenecks and two expansions of effective population size were identified for the MD1 group of cultivated mandarins. However, in the MD2 group there was a long and continuous decrease in the population size. MD1 and MD2 mandarins showed different patterns of interspecific introgression from cultivated pummelo species. We identified a region of high divergence in an aconitate hydratase (ACO) gene involved in the regulation of citrate content, which was possibly under selection during the domestication of mandarin. This study provides concrete genetic evidence for the geographical origin of extant wild mandarin populations and sheds light on the domestication and evolutionary history of mandarin.

Seed germination and biochemical profile of Citrus reticulata (Kinnow) exposed to green synthesised silver nanoparticles

The biosynthesis of silver nanoparticles (AgNPs) is substantial for its applications in different fields. The Moringa oleifera leaves were used as reducing and stabilising agent for the biosynthesis of AgNPs. The synthesised AgNPs were characterised through UV-visible spectroscopy, zeta analyser, scanning electron microscopy (SEM) and energy dispersive Xray (EDX). In this study, effects of the synthesised AgNPs were also evaluated on nucellus tissues germination frequency and biochemical parameters of plant tissues. Nucellus tissues of Citrus reticulata were inoculated on MS medium supplemented with 10, 20, 30 and 40 µg/ml suspension of the synthesised AgNPs. Green synthesised AgNPs enhanced the in vitro germination because of low toxicity and nonfriendly issues. Significant results were obtained for germination parameters i.e. root and shoot length and seedling vigour index in response to 30 µg/ml suspension of green synthesised AgNPs. The 30 µ/ml suspension of AgNPs also enhanced antioxidant activity (41%) and SOD activity (0.36 nM/min/mg FW) while total phenolic content (4.7 µg/mg FW) and total flavonoid content (1.1 µg/mg FW) was significantly high when MS medium was fortified with 40 µg/ml suspension of the synthesised AgNPs. The content of total protein was significant (558 µg/BSA Eq/mg FW) in control plantlets as compared to the other treatments.

Ranking genome-wide correlation measurements improves microarray and RNA-seq based global and targeted co-expression networks

Co-expression networks are essential tools to infer biological associations between gene products and predict gene annotation. Global networks can be analyzed at the transcriptome-wide scale or after querying them with a set of guide genes to capture the transcriptional landscape of a given pathway in a process named Pathway Level Coexpression (PLC). A critical step in network construction remains the definition of gene co-expression. In the present work, we compared how Pearson Correlation Coefficient (PCC), Spearman Correlation Coefficient (SCC), their respective ranked values (Highest Reciprocal Rank (HRR)), Mutual Information (MI) and Partial Correlations (PC) performed on global networks and PLCs. This evaluation was conducted on the model plant Arabidopsis thaliana using microarray and differently pre-processed RNA-seq datasets. We particularly evaluated how dataset × distance measurement combinations performed in 5 PLCs corresponding to 4 well described plant metabolic pathways (phenylpropanoid, carbohydrate, fatty acid and terpene metabolisms) and the cytokinin signaling pathway. Our present work highlights how PCC ranked with HRR is better suited for global network construction and PLC with microarray and RNA-seq data than other distance methods, especially to cluster genes in partitions similar to biological subpathways.

Effect of drying temperature on the sugars, organic acids, limonoids, phenolics, and antioxidant capacities of lemon slices

Changes in contents of sugars, organic acids, limonoids, phenolics contents, and antioxidant capacities of lemon slices dried at different temperatures were evaluated. Air drying (AD) promoted losses of sugars, citric acid, ascorbic acid, extractable phenolics (EPs), and non-extractable phenolics (NEPs), while it introduced an increase in limonoids. Phenolics of lemon were mainly presented in their extractable form. Hesperidin and eriocitrin were the main EPs; protocatechuic acid and poncirin were the predominant NEPs. The decrease in extractable phenolic acid, EP, and NEP content in lemon is lower at low drying temperatures, while the increase in non-extractable phenolic acid content is higher at high drying temperatures. The antioxidant capacity of EP was higher than that of NEP. Phenolics contributed to antioxidant capacities of lemon slices, and flavonoids were the main contributors among phenolics. Considering limonoids contents and the high levels of EP, NEP, and antioxidant capacities, AD at 60 °C could be an appreciate treatment for dehydrating lemon slices.

Comparison and multivariate statistical analysis of anthocyanin composition in Lycium ruthenicum Murray from different regions to trace geographical origins: The case of China

Anthocyanin composition in forty-five Lycium ruthenicum Murray (LRM) samples grown in China was identified by high-performance liquid chromatography-electrospray ionisation-mass spectrometry (HPLC-ESI-MS) and quantified by HPLC with a diode array detector (HPLC-DAD). The results showed that the overall pattern of anthocyanin composition of LRM from different provinces was the same, while the individual and total anthocyanin concentrations, were significantly different, indicating an important impact of geographical origin on anthocyanin composition, which can be considered as credible indices for LRM classification. Principal component analysis (PCA) and linear discriminant analysis (LDA) were applied to develop discrimination models for the anthocyanin concentrations. PCA clearly separated the LRM based on its geographical origins. LDA satisfactorily categorized the samples by providing a 100% success rate based on geographical origins. The results obtained could be used to trace the geographical origin of LRM.

Dietary feeding of freeze-dried whole cranberry inhibits intestinal tumor development in Apcmin/+ mice

It is increasingly perceived that dietary components have been linked with the prevention of intestinal cancer. Cranberry is a rich source of phenolic constituents and non-digestible fermentable dietary fiber, which shows anti-proliferation effect in colorectal cancer cells. Herein, we investigated the efficacy of long-term cranberry diet on intestinal adenoma formation in Apc^min/+ mice. Apc^min/+ mice were fed a basal diet or a diet containing 20% (w/w) freeze-dried whole cranberry powder for 12 weeks, and the number and size of tumors were recorded after sacrifice. Our results showed that cranberry strongly prevented the growth of intestinal tumors by 33.1%. Decreased cell proliferation and increased apoptosis were observed in tumors of cranberry-fed mice. Cranberry diet reduced the expression profile of colonic inflammatory cytokines (IFN-γ, IL-1β and TNF-α) accompanied with increased levels of anti-inflammatory cytokines (IL-4 and IL-10). Moreover, the number of colonic goblet cells and MUC2 production were increased, and the intestinal barrier function was also improved. In addition, cranberry diet increased caecal short chain fatty acids concentrations, and down-regulated epidermal growth factor receptor signaling pathway. These data firstly show the efficacy and associated mechanisms of cranberry diet on intestinal tumor growth in Apc^min/+ mice, suggesting its chemopreventive potential against intestinal cancer.

An Integrated Approach to Mandarin Processing: Food Safety and Nutritional Quality, Consumer Preference, and Nutrient Bioaccessibility

Mandarins are a member of the Citrus genus and are the focus of growing commercial interest, with satsuma mandarins (Citrus unshiu) and the common mandarin (Citrus reticulata Blanco) being the most important mandarin varieties. The possible health benefits and functional properties of those fruits are often associated with the antioxidative function of vitamin C, carotenoids, and phenolic compounds. While most mandarins are consumed fresh, many are processed into juices (mostly cloudy), usually via thermal processing which can lead to the creation of off-flavors and may diminish nutritional quality. The aim of this review is to summarize the most significant and recent information on the safety, sensorial properties, and nutritional benefits of mandarins and their processing into juice. The article also discusses recent information regarding the bioaccessibility of valuable, mandarin specific, compounds.

Characterization and Metabolic Diversity of Flavonoids in Citrus Species

Flavonoids are widely distributed in plants and play important roles in many biological processes. Citrus fruits are rich dietary sources of flavonoids. However, there have been very few reports about the comprehensive metabolic profile and natural diversity of flavonoids in different tissues of various Citrus cultivars. In this study, based on the 7416 metabolic signals detected with non-targeted metabolomics approach, Principal Component Analysis revealed the flavedo has the largest differences from other tissues in metabolite levels; as many as 198 flavonoid signals were then detected in 62 Citrus germplasms from 5 species mainly cultivated worldwide, while 117 flavonoids were identified, including 39 polymethoxylated flavonoids (PMFs), 7 flavones, 10 C-O-glycosylflavonoids, 44 O-glycosylflavonoids, 10 C-glycosylflavonoids and 7 newly annotated O-glycosylpolymethoxylated flavonoids. Tissue-specific accumulations were observed: O-glycosylated flavonoids were abundant in all fruit tissues, while PMFs were accumulated preferentially in the flavedo. Among different species, mandarins had the highest levels of PMFs and O-glycosylpolymethoxylated flavonoids, followed by sweet oranges. Based on the flavonoid profiles, 62 germplasms could be clearly grouped into five distinct clusters via hierarchical clustering analysis, which were perfectly matched with their species, with sweet oranges and mandarins clustering closely and being further away from other three species.

Antioxidant Capacity, Anticancer Ability and Flavonoids Composition of 35 Citrus (Citrus reticulata Blanco) Varieties

Citrus (Citrus reticulate Blanco) is one of the most commonly consumed and widely distributed fruit in the world, which is possessing extensive bioactivities. Present study aimed to fully understand the flavonoids compositions, antioxidant capacities and in vitro anticancer abilities of different citrus resources. Citrus fruits of 35 varieties belonging to 5 types (pummelos, oranges, tangerines, mandarins and hybrids) were collected. Combining li quid chromatography combined with electrospray ionization mass spectrometry (LC-ESI-MS/MS) and ultra-performance liquid chromatography combined with diode array detector (UPLC-DAD), a total of 39 flavonoid compounds were identified, including 4 flavones, 9 flavanones and 26 polymethoxylated flavonoids (PMFs). Each citrus fruit was examined and compared by 4 parts, flavedo, albedo, segment membrane and juice sacs. The juice sacs had the lowest total phenolics, following by the segment membrane. Four antioxidant traits including 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC) and cupric reducing antioxidant capacity (CUPRAC) were applied for the antioxidant capacities evaluation. Three gastric cancer cell lines, SGC-7901, BGC-823 and AGS were applied for the cytotoxicity evaluation. According to the results of correlation analysis, phenolics compounds might be the main contributor to the antioxidant activity of citrus extracts, while PMFs existing only in the flavedo might be closely related to the gastric cancer cell line cytotoxicity of citrus extracts. The results of present study might provide a theoretical guidance for the utilization of citrus resources.

Characterization of phenolic profile and antioxidant capacity of different fruit part from lemon (Citrus limon Burm.) cultivars

Phenolic composition and antioxidant capacity of different fruit part including peel, pulp, juice, whole fruit and seed from five lemon cultivars (Feiminailao, Cuningmeng Limeng, Pangdelusaningmeng, Beijingningmeng) were investigated. Caffeic acid (9.31-741.4 μg/g FW) and chlorogenic acid (2.7-527.5 μg/g FW) were the dominant phenolic acid in fruit tested, Pangdelusaningmeng (PD) and Limeng peels with the highest contents, respectively. Hesperidin was the predominant flavanone (10.27-3315 μg/g FW), Cuningmeng (CN) peels with the highest level. PD peels had rich rutin, CN seeds had rich eriocitrin. Nobiletin was the main polymethoxylated flavonoids identified, PD with the highest level. CN peels contained rich tangeretin. Overall, peels and whole fruit had significantly higher level of phenolics than other fruit parts, and seeds were good source of flavonoids. PD and CN not only contained higher level of phenolic, but also presented higher antioxidant capacity than other cultivars tested, and are of great value for human nutrition.

In Vitro Lipophilic Antioxidant Capacity, Antidiabetic and Antibacterial Activity of Citrus Fruits Extracts from Aceh, Indonesia

This study reports in vitro lipophilic antioxidant, inhibition of α-amylase and antibacterial activities of extracts of peel and pulp of citrus samples from Aceh, Indonesia. HPLC (high-performance liquid chromatography), phytochemical, and FTIR (fourier transform infrared) analysis detected carotenoids, flavonoids, phenolic acids and terpenoids, contributing to the biological potencies. Most peel and pulp extracts contained lutein and lower concentrations of zeaxanthin, α-carotene, β-carotene and β-cryptoxanthin. The extracts also contained flavanone glycosides (hesperidin, naringin and neohesperidin), flavonol (quercetin) and polymethoxylated flavones (sinensetin, tangeretin). L-TEAC (lipophilic trolox equivalent antioxidant capacity) test determined for peel extracts higher antioxidant capacity compared to pulp extracts. All extracts presented α-amylase inhibitory activity, pulp extracts showing stronger inhibitory activity compared to peel extracts. All extracts inhibited the growth of both gram (+) and gram (−) bacteria, with peel and pulp extracts of makin showing the strongest inhibitory activity. Therefore, local citrus species from Aceh are potential sources of beneficial compounds with possible health preventive effects.

Polyphenolic content and bactericidal effect of Mexican Citrus limetta and Citrus reticulata

In this study, total phenolics, total flavonoids, hesperidin and ascorbic acid contents in bagasse, juice and seed of mexican sweet lime (Citrus limetta) and mandarine (Citrus reticulata) were determined at two commercial maturity stages (maturation index), as well as their bactericidal effect on Escherichia coli and Staphylococcus aureus. The results showed that bagasses had the highest total phenolics, total flavonoids, and hesperidin content for both, C. limetta, and C. reticulata; highest ascorbic acid contents were found in C. limetta juice (3.36 ± 0.25 mg g^-1 DW) and C. reticulata bagasse (3.83 ± 0.37 mg g^-1 DW). All tested extracts showed bacterial growth inhibition at 50 and 800 µg mL^-1. Bagasse extracts of both fruits showed the highest inhibitions (>90%) on tested bacteria. Total phenolics, total flavonoids, and hesperidin contents, as well as bactericidal effect increased with maturity. Results indicated that both Mexican citric fruits (C. limetta and C. reticulata) were good sources of antioxidant and bactericidal agents.

Extractable and Non-Extractable Phenolics and Antioxidant Capacity of Mandarin Waste Dried at Different Temperatures

The mandarin industry is generating more waste due to the increasing demand for juice. In this study, extractable and non-extractable phenolics as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), ferric reducing ability of plasma (FRAP), and oxygen radical absorbance capacity (ORAC) antioxidant activities in Satsuma mandarin waste dried at different temperatures were determined. The amounts of non-extractable total phenols, total flavonoids, and condensed tannins measured in mandarin waste dried at 120 °C were 39.4, 44.3, and 45.6 %, respectively, which were higher than those of fresh-mandarin waste. Dried mandarin waste is rich in extractable and non-extractable hesperidin (259.86 and 182.52 mg/g, respectively) and eriocitrin (85.12 and 197.24 mg/g, respectively), as well as non-extractable gallic acid (36.08 μg/g). The antioxidant capacities of extractable and non-extractable phenolics, from the highest to the lowest, were ABTS > ORAC > DPPH > FRAP and ORAC > ABTS > DPPH > FRAP, respectively. The information reported here may encourage mandarin industry operators to re-evaluate their by-products, extending the application of mandarin fruits and reducing waste.

Bioactivities and Health Benefits of Wild Fruits

Wild fruits are exotic or underutilized. Wild fruits contain many bioactive compounds, such as anthocyanins and flavonoids. Many studies have shown that wild fruits possess various bioactivities and health benefits, such as free radical scavenging, antioxidant, anti-inflammatory, antimicrobial, and anticancer activity. Therefore, wild fruits have the potential to be developed into functional foods or pharmaceuticals to prevent and treat several chronic diseases. In the present article, we review current knowledge about the bioactivities and health benefits of wild fruits, which is valuable for the exploitation and utilization of wild fruits.

Antioxidant and antiplatelet activities of flavonoid-rich fractions of three citrus fruits from Korea

Three different fractional (methanol, ethyl acetate and hexane) extracts from yuzu (Citrus junos Sieb ex Tanaka), hallabong [(C. unshiu Marcov × C. sinensis Osbeck) × C. reticulata Blanco] and orange (C. sinensis) were evaluated for their antioxidant activity and antiplatelet effects. 2,2-Diphenyl-1-Picrylhydrazyl (DPPH), cupric reducing antioxidant capacity (CUPRAC) and ferric-reducing antioxidant power (FRAP) methods were used for the antioxidant activity tests. Total flavonoids and total phenolics were also evaluated spectrophotometrically. The ethyl acetate fraction contained the highest total flavonoid and total phenolic content and exhibited the highest antioxidant activities (185.2 ± 14.5 and 208.7 ± 17.5 mg/g dry extract for FRAP and CUPRAC values, respectively). The total phenolic and total flavonoid content ranged from 58.2 ± 1.4 to 102.4 ± 8.6 and 19.6 ± 0.5 to 64.3 ± 0.8 mg/g dry extract, respectively. The results of DPPH assay showed that ethyl acetate fractions had the least IC50 values (0.12 ± 0.002, 0.04 ± 0.0006, in mg/mL for orange and hallabong samples, respectively) followed by the hexane fraction (0.19 ± 0.007 mg/mL) of the orange sample. For all fractions, the antioxidant activity and contents of total phenolics and total flavonoids correlated well with each other. In vitro investigation of the antiplatelet effect showed that ethyl acetate fraction has the highest inhibition (84.3 ± 5.8 to 96.1 ± 1.8 %). Hexane and MeOH fractions of hallabong and orange samples inhibited platelet aggregations by less than or equal to 41 %.

Comparisons and correlations of phenolic profiles and anti-oxidant activities of seventeen varieties of pineapple

Major phenolic, β-carotene, and ascorbic acid (AA) contents in 17 pineapple varieties were quantified and compared. Anti-oxidant activities were evaluated using 2,2-Diphenyl-l-picrylhydrazyl (DPPH), 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), ferric reducing anti-oxidant power (FRAP), and metal chelating capacity (MCC) assays. MD-2 exhibited the highest AA and total phenolic (TP) contents and DPPH and ABTS assay results, but was lower in β-carotene contents. Ripley had the highest total flavonoid (TF) content with a low AA content. Comte de Pairs exhibited the highest MCC and the lowest FRAP values. TP contents and both DPPH and ABTS activities, FRAP values and both AA contents and DPPH activities, and TF contents and ABTS activities were positively correlated. MD-2 exhibited the greatest diversity of phenolics and highest anti-oxidant activities in all assays. Information included herein can be useful for development of pineapple-based food products containing high levels of health promoting anti-oxidants.

Bioactive Flavonoids, Antioxidant Behaviour, and Cytoprotective Effects of Dried Grapefruit Peels (Citrus paradisi Macf.)

Grapefruit (Citrus paradisi Macf.) is an important cultivar of the Citrus genus which contains a number of nutrients beneficial to human health. The objective of the present study was to evaluate changes in bioactive flavonoids, antioxidant behaviour, and in vitro cytoprotective effect of processed white and pink peels after oven-drying (45°C–60°C) and freeze-drying treatments. Comparison with fresh grapefruit peels was also assessed. Significant increases in DPPH, FRAPS, and ABTS values were observed in dried grapefruit peel samples in comparison with fresh peels, indicating the suitability of the treatments for use as tools to greatly enhance the antioxidant potential of these natural byproducts. A total of thirteen flavonoids were quantified in grapefruit peel extracts by HPLC-MS/MS. It was found that naringin, followed by isonaringin, was the main flavonoid occurring in fresh, oven-dried, and freeze-dried grapefruit peels. In vivo assay revealed that fresh and oven-dried grapefruit peel extracts (45°C) exerted a strong cytoprotective effect on SH-SY5Y neuroblastoma cell lines at concentrations ranging within 0.1–0.25 mg/mL. Our data suggest that grapefruit (Citrus paradisi Macf.) peel has considerable potential as a source of natural bioactive flavonoids with outstanding antioxidant activity which can be used as agents in several therapeutic strategies.

HPTLC Fingerprinting and Cholinesterase Inhibitory and Metal-Chelating Capacity of Various Citrus Cultivars and Olea europaea

Inhibitory activity of thirty-one ethanol extracts obtained from albedo, flavedo, seed and leaf parts of 17 cultivars of Citrus species from Turkey, the bark and leaves of Olea europaea L. from two locations (Turkey and Cyprus) as well as caffeic acid and hesperidin was tested against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), related to the pathogenesis of Alzheimer's disease, using ELISA microtiter assays at 500 µg/mL. Metal-chelating capacity of the extracts was also determined. BChE inhibitory effect of the Citrus sp. extracts was from (7.7±0.7) to (70.3±1.1) %, whereas they did not show any inhibition against AChE. Cholinesterase inhibitory activity of the leaf and bark ethanol extracts of O. europaea was very weak ((10.2±3.1) to (15.0±2.3) %). The extracts had either no or low metal-chelating capacity at 500 µg/mL. HPTLC fingerprinting of the extracts, which indicated a similar phytochemical pattern, was also done using the standards of caffeic acid and hesperidin with weak cholinesterase inhibition. Among the screened extracts, the albedo extract of C. limon 'Interdonato', the flavedo extracts of 'Kara Limon' and 'Cyprus' cultivars and the seed extract of C. maxima appear to be promising as natural BChE inhibitors.

Phenolic compositions and antioxidant activities of grapefruit (Citrus paradisi Macfadyen) varieties cultivated in China

The phenolic compounds in different fruit parts including the flavedos, albedos, segment membranes, juice vesicles and seeds of nine grapefruit varieties cultivated in China were determined and their antioxidant capacities were evaluated using three methods. Naringin and neohesperedin were the dominant flavonoids in all grapefruit tested. Fenghongtangmuxun and Jiwei flavedo had the highest contents of naringin (5666.82 μg/g DW) and neohesperedin (1022 μg/g DW), respectively. Gallic acid was the major phenolic acid in all grapefruit tested, and Jiwei juice vesicles had the highest content of gallic acid (343.7 μg/g DW). Fenghongtangmuxun juice vesicles were rich in chlorogenic acid (110.23 μg/g DW), caffeic acid (53.86 μg/g DW) and ferulic acid (23.12 μg/g DW). Overall, the flavedo was rich in flavonoid, while juice vesicle had high amounts of phenolic acid. The Jiwei, Fenghongtangmuxun, Maxu, Huoyan and Hongmaxu grapefruit cultivars contained more phenolics and exhibited higher antioxidant capacities than Shatianyou and Liangpingyou pummelos, and were good sources of natural phytochemical antioxidants.

Antioxidant activity of Citrus fruits

Citrus is well-known for its nutrition and health-promotion values. This reputation is derived from the studies on the biological functions of phytochemicals in Citrus fruits and their derived products in the past decades. In recent years, the antioxidant activity of Citrus fruits and their roles in the prevention and treatment of various human chronic and degenerative diseases have attracted more and more attention. Citrus fruits are suggested to be a good source of dietary antioxidants. To have a better understanding of the mechanism underlying the antioxidant activity of Citrus fruits, we reviewed a study on the antioxidant activity of the phytochemicals in Citrus fruits, introduced methods for antioxidant activity evaluation, discussed the factors which influence the antioxidant activity of Citrus fruits, and summarized the underlying mechanism of action. Some suggestions for future study were also presented.

Ougan (Citrus reticulata cv. Suavissima) flavedo extract suppresses cancer motility by interfering with epithelial-to-mesenchymal transition in SKOV3 cells

BACKGROUND

Ougan (Citrus reticulata cv. Suavissima) flavedo extract (OFE) exhibited potential anti-tumor effects with unclear underlying mechanisms. This study aims to evaluate the potential anti-metastatic activities of OFE on human ovarian cancer cells, and investigate its inhibitory effect on epithelial-to-mesenchymal transition (EMT).

METHODS

Ougan fruits were harvested. Flavedo tissues were separated and made into freeze-dried powder. Then OFE were extracted from the powder. The components of OFE were identified by the high performance liquid chromatography system with a detection wavelength of 280 nm for flavanones and 330 nm for polymethoxylated flavones. Cell viability was assessed by Sulforhodamine B assay. The effects on cancer cell migration and motility were evaluated by wound-healing and transwell assays. The mechanisms of action were investigated by examining the modulation by OFE on EMT-related signaling pathways at the concentrations of 4 μg/mL and 20 μg/mL, using qRT-PCR and western blot analyses.

RESULTS

Non-cytotoxic concentrations of OFE significantly suppressed the cellular migration (4 μg/mL, P = 0.005 vs. control group; 20 μg/mL, P = 0.003 vs. control group) and motility (4 μg/mL, P < 0.001 vs. control group; 20 μg/mL, P < 0.001 vs. control group) of SKOV3 cells, and inhibited transforming growth factor-β1 (TGF-β1)-induced E-cadherin loss (4 μg/mL, P = 0.002 vs. control group; 20 μg/mL, P = 0.001 vs. control group) and mesenchymal marker upregulation, e.g., N-cadherin (4 μg/mL, P = 0.027 vs. control group; 20 μg/mL, P = 0.013 vs. control group), vimentin (4 μg/mL, P = 0.036 vs. control group; 20 μg/mL, P = 0.015 vs. control group) and fibronectin (4 μg/mL, P < 0.001 vs. control group; 20 μg/mL, P < 0.001 vs. control group).

CONCLUSIONS

The anti-metastatic ability of OFE inhibited EMT by interfering with the canonical TGF-β1-SMAD-Snail/Slug axis.

Quantitative analysis of flavanones from citrus fruits by using mesoporous molecular sieve-based miniaturized solid phase extraction coupled to ultrahigh-performance liquid chromatography and quadrupole time-of-flight mass spectrometry

An analytical procedure based on miniaturized solid phase extraction (SPE) and ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry was developed and validated for determination of six flavanones in Citrus fruits. The mesoporous molecular sieve SBA-15 as a solid sorbent was characterised by Fourier transform-infrared spectroscopy and scanning electron microscopy. Additionally, compared with reported extraction techniques, the mesoporous SBA-15 based SPE method possessed the advantages of shorter analysis time and higher sensitivity. Furthermore, considering the different nature of the tested compounds, all of the parameters, including the SBA-15 amount, solution pH, elution solvent, and the sorbent type, were investigated in detail. Under the optimum condition, the instrumental detection and quantitation limits calculated were less than 4.26 and 14.29ngmL(-1), respectively. The recoveries obtained for all the analytes were ranging from 89.22% to 103.46%. The experimental results suggested that SBA-15 was a promising material for the purification and enrichment of target flavanones from complex citrus fruit samples.

A New Flavonoid Glycoside and Potential Antifungal Activity of Isolated Constituents from the Flowers of Lilium Lancifolium

Lancifolide A, 4′,7-dimethoxyisorhamnetin-3-O-α-l-rhamnosyl (1å2)[α-l-arabinosyl (1å6)]-β-d-glucopyranoside, a new flavonoid glycoside, has been isolated from the flowers of Lilium lancifolium, along with five known flavonoid glycosides, which were reported to be obtained for the first time from this plant. Their structures were elucidated on the basis of spectroscopic methods and from literature values. All components were tested for antifungal activity.