Osbeck Cv Research Articles

Effects of storage time and temperature on the chemical composition and organoleptic quality of Gannan navel orange (Citrus sinensis Osbeck cv. Newhall)

Effects of storage time and temperature on the chemical composition and organoleptic quality of Gannan navel orange (Citrus sinensis Osbeck cv. Newhall)

Variations of the chemical composition of Citrus sinensis Osbeck cv. Newhall fruit in relation to the symptom severity of Huanglongbing

In this study, the chemical compositions of Huanglongbing-symptomatic (HLB-SY) and Huanglongbing-asymptomatic (HLB-AS) Newhall navel oranges were comprehensively studied. Our results indicated that the orange juice of HLB-SY contained fewer amounts of TSS (total soluble solids), fructose, glucose, sucrose and Vc (vitamin C), while having more limonin and TA (titratable acidity) when compared to the respective one in HLB-AS juice, which was consistent with most of the previous reports. The hesperidin and didymin, however, were significantly (p < 0.05) less present in HLB-SY juice, with narirutin content being almost unchangeable, differing from the majority of earlier studies. On the contrary, the contents of primary flavonoids in HLB-SY peel, involving narirutin, hesperidin, didymin, 3,6,7,8,2′,5′-hexamethoxyflavone, nobiletin, 4′,5,6,7-tetramethoxyflavone, 3,3′,4′,5,6,7,8-heptamethoxyflavone and tangeretin, were significantly (p < 0.05) higher than those in HLB-AS peel. Meanwhile, when compared to the HLB-AS peel oil, the HLB-SY peel oil contained a significantly (p < 0.05) higher percentage of 4 monoterpenoids (sabinene, 3-carene, terpinolene, limonene-1,2-epoxide), 4 fatty aldehydes (octanal, nonanal, decanal, undecanal), and 3 alcohols (4-thujanol, linalool, α-terpineol), while showing significantly lower in the percentage of 5 terpene aldehydes (citronellal, geranial, neral, β-sinensal, α-sinensal), 3 sesquiterpenoids (valencene, β-cadinene, nootkatone), and limonene. The principal components analysis (PCA) was used to visualize the correlations amongst the variation of chemical compositions. The results presented here might be beneficial for the value-added utilization of HLB fruits.

Effects of field inoculation with arbuscular mycorrhizal fungi and endophytic fungi on fruit quality and soil properties of Newhall navel orange

Beneficial fungi - including difficult - to - culture arbuscular mycorrhizal fungi (AMF) and the culturable endophytic fungus Piriformospora indica - play positive roles in hosts under controlled conditions, whereas information regarding the application of these fungi in field citrus (a mycorrhizal - dependent plant) is scarce. The present study aims to analyze the effects of two AMF species (Diversispora spurca and D. versiformis) and an endophytic fungus (P. indica) on the fruit quality and soil properties of Newhall navel oranges (Citrus sinensis Osbeck cv. Newhall) grafted on trifoliate oranges in the field. The results showed the improvement of root fungal colonization following fungal inoculation. The fungal inoculations increased the soil's acid, neutral, alkaline, and total phosphatase activity, as well as soil Bray-P content; increased the distribution of water-stable aggregates, mainly in the size range of 2–4 mm; and stimulated the production of easily extractable, difficultly extractable, and total glomalin-related soil proteins in a fungal-species-dependent manner, which was positively correlated with soil aggregate stability. Fungal inoculations, to some extent, improved external fruit quality, depending on the fungal species. Among the three fungi, only D. versiformis significantly increased the fruits' soluble solid content, but all three together promoted fruit glucose, fructose, and sucrose content. The two AMF species dramatically increased fruit phosphorus (P) content, while P. indica distinctly reduced it. D. versiformis also significantly elevated fruit potassium (K), magnesium (Mg), and manganese (Mn) content, D. spurca improved fruit copper (Cu), zinc (Zn), K, and Mg content, and P. indica increased fruit iron (Fe) and Zn content, compared with non-inoculated controls. Our results indicate that the field inoculation of citrus with AMF and P. indica partially improved fruit quality and soil properties, providing a pathway for P. indica to partially replace AMF in field citrus applications.

Comparative analysis of the cuticular waxes and related gene expression between ‘Newhall’ and ‘Ganqi 3’ navel orange during long-term cold storage

Previously, we obtained a wax-deficient mutant ‘Ganqi 3’ (MT) from ‘Newhall’ navel orange (Citrus sinensis [L.] Osbeck cv. Newhall, WT). The weight loss and postharvest decay in MT fruit were much higher than those in WT fruit after long-term cold storage. To understand the underlying mechanism, the changes in the morphology, chemical composition and gene expression of cuticular waxes between WT and MT fruit were compared during 150 days of storage at 4 °C. The density of epicuticular wax crystals and the contents of most of the aliphatic wax fractions in MT fruit were much lower than those in WT fruit over 90 days of storage. Further research revealed that the differences in the morphology and chemical composition of cuticular waxes might be important causes for the differences of postharvest weight loss and decay rates between WT and MT fruit. Notably, the expression profiles of 16 wax-related genes in WT and MT fruit were consistent with the change trends of corresponding cuticular wax components during cold storage. These results suggest that the morphology and chemical composition of cuticular waxes may be regulated by wax-related genes and play an important role in regulating the postharvest weight loss and the tolerances to postharvest decay in navel orange.

Postharvest Application of 24-Epibrassinolide Reduces Chilling Injury Symptoms and Enhances Bioactive Compounds Content and Antioxidant Activity of Blood Orange Fruit.

Blood oranges (Citrus sinensis L. Osbeck cv. Sanguinello) fruit were treated with 24-epibrassinolide (Br) at 1, 5, and 10 μM previous to storage at 5°C during 42 days. The samples were analyzed after 14, 28, and 42 days plus 2 days at 20°C. Chilling injury was reduced in Br-treated fruit based on the lower percentage of electrolyte leakage and visual symptoms of peel dehydration and browning. Treated fruit showed lower acidity losses, due to retention of the main organic acids’ concentration (citric and malic acids), as well as was higher content of sugars (sucrose, fructose, and glucose), especially in those fruit treated with the highest concentration (10 μM). Total phenolics and hydrophilic total antioxidant activity (H-TAA) decreased in control fruit over storage, while Br-treated fruit showed significantly higher concentration. In addition, total anthocyanins were enhanced in Br-treated oranges, which were correlated with color Hue angle. Overall, the application of Br at 10 μM provides results increasing the storability of blood oranges and their content on bioactive compounds with antioxidant activity.

Complete genome sequence of citrus yellow spot virus, a newly discovered member of the family Betaflexiviridae.

A novel plant virus with a positive single-stranded (+ss) RNA genome was detected in Taibei pomelo (Citrus grandis (L.) Osbeck cv. Taibeiyou) in China by high-throughput sequencing (HTS). Tentatively named "citrus yellow spot virus" (CiYSV), it has 8,061 nucleotides (nt) excluding the poly(A) tail and contains three open reading frames (ORFs). ORF1 is predicted to encode a replicase polyprotein (RP) with conserved domains typical of members of the family Betaflexiviridae. ORF2 encodes a protein sharing the highest sequence identity with the putative movement protein (MP) found in the negative-stranded RNA virus Trifolium pratense virus B (TpVB, MH982249, genus Cytorhabdovirus). ORF3 overlaps ORF2 by 137 nt and encodes a predicted coat protein (CP) that is distantly related to those of betaflexiviruses. Phylogenetic analysis based on the MP amino acid sequence showed that the CiYSV clustered with cytorhabdoviruses rather than betaflexiviruses, whilst trees based on the whole genome, RP, and CP showed it to belong to the family Betaflexiviridae but to be distinct from any other known betaflexiviruses. These results suggest that the CiYSV should be considered the first member of a tentative new genus in the family Betaflexiviridae.

Chemical composition, antioxidant, antibacterial, and tyrosinase inhibition activity of extracts from Newhall navel orange (Citrus sinensis Osbeck cv. Newhall) peel.

Newhall navel orange (Citrus sinensis Osbeck cv. Newhall) is the major navel orange cultivar planted in China. Almost all Newhall navel orange peels produced in that country are currently discarded, which is not only harmful to the environment but also a waste of resources. It is therefore necessary to carry out research to explore the utilization potential of this resource. A 95% ethanol extract (EE) of Newhall orange peel was prepared and fractionated into three subextracts: petroleum ether extract (PEE), ethyl acetate extract (EtOAcE), and water extract (WE) by simple liquid / liquid extractions. These four extracts were then subjected to antioxidant, antibacterial, and tyrosinase inhibition assays. Interestingly, EtOAcE was significantly superior to all other three extracts, exhibiting the best biological effects. The total polyphenol content (TPC), total flavonoid content (TFC), and primary individual flavonoids of these four extracts were analyzed and compared. This was followed by principal component analysis (PCA) and the Pearson's correlation test. The result indicates that the primary bioactive compounds responsible for the biological effects of the EtOAcE are sinensetin, 4',5,6,7-tetramethoxyflavone, nobiletin, 3,3',4',5,6,7-hexamethoxyflavone, and narirutin. In view of its easy preparation and potent biological effects, EtOAcE might demonstrate excellent application potential in various industrial areas. This study successfully identified EtOAcE as a potent naturally occurring antioxidant, antibacterial, and tyrosinase inhibitory agent, which might add value to the utilization of Newhall navel orange peel in the food, cosmetic, and pharmaceutical industries. © 2020 Society of Chemical Industry.

Temporal Dynamics of Candidatus Liberibacter asiaticus Titer in Mature Leaves from Citrus sinensis cv Valencia Are Associated with Vegetative Growth.

Huanglongbing, a highly destructive disease of citrus species, is associated with a fastidious, gram-negative, phloem-limited bacteria (Candidatus Liberibacter spp.). In Florida, the causative agent of Huanglongbing (HLB) is C. Liberibacter asiaticus (CLas) and it is transmitted by the insect vector, Asian citrus psyllid (Diaphorina citri Kuwayama). Previous investigations have revealed systemic infection of CLas with an erratic and uneven distribution of pathogen in tree phloem. However, previous investigations did not consider the potential impact of plant vegetative growth on presence/absence of CLas in planta. Our objectives were to determine: 1) the effect of vegetative growth of Citrus sinensis (L.) Osbeck cv Valencia on detection of CLas in mature leaves, and 2) the impact of CLas inoculation frequency on progression of CLas titer in citrus leaves through the first year of infection. Temporal dynamics of CLas detection were associated with vegetative flush growth. Surprisingly, there was no difference in CLas titer detected between plants exposed to infected vectors for a one-time 7 d inoculation access period, as compared with plants exposed to continuously breeding CLas-infected insects over the course of an entire year of plant infection. Our results suggest that the CLas bacterium is transported through phloem during annual movement of carbon compounds needed for vegetative plant growth, including transportation from roots to mature leaves. These results highlight the importance of vegetative growth on temporal dynamics of CLas in citrus, and suggest a critical role of the sink-source interaction on presence/absence of CLas in leaves.

Effects of storage conditions and heat treatment on the hesperidin concentration in Newhall navel orange (Citrus sinensis Osbeck cv. Newhall) juice

The effects of storage condition and heat treatment on the hesperidin concentration in Newhall navel orange (Citrus sinensis Osbeck cv. Newhall) juice were investigated systematically in the present study. Our results indicated that, 1) the hesperidin concentration in orange juice gradually decreased during storage, even when the juice was stored at low temperature; 2) hesperidin was stable in juice subjected to either heat or concentrating treatment; 3) the total content of hesperidin in juice remained almost unchanged, although the hesperidin would gradually settle out from the juice, possibly caused by the decomposition of vitamin C during storage, resulting in the reduction of hesperidin concentration in juice. The experimental observations in this study might help clarify some inconsistent reports on hesperidin content in the literature and provide valuable information for the measurement of hesperidin in orange juice. Meanwhile, the results of our study suggested that the hesperidin content in juice should not be considered as a marker for identification of NFC (not from concentrate) orange juice.

Flavonoids composition and antioxidant potential assessment of extracts from Gannanzao Navel Orange (Citrus sinensis Osbeck Cv. Gannanzao) peel

The antioxidant effect of 95% ethanol extract and its three subfractions, PE (petroleum ether), EtOAc (ethyl acetate), and water extracts, from Gannanzao navel orange peel, were evaluated by ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)), DPPH (1,1-diphenyl-2-picryl-hydrazyl) and FRAP (ferric reducing/antioxidant potential) methods for the first time. Furthermore, the TPC (total polyphenol content), TFC (total flavonoid content), and primary individual flavonoids of the four extracts were analyzed and compared. The results indicated that: (1) the EtOAc extract exhibited the best antioxidant potential among these four extracts in all three antioxidant bioassay platforms; (2) Corresponding to the antioxidant potential, the EtOAc extract contained the highest contents of both TPC and TFC; (3) Compared with other extracts, the EtOAc extract was significantly (p < 0.01) rich in the contents of narirutin, sinensetin, nobiletin, 4′,5,6,7-tetramethoxyflavone, and 3,3′,4′,5,6,7-hexamethoxyflavone, which might be the main bioactive compounds responsible for the excellent antioxidant potential of EtOAc extract.

Comparative Metabolite Profiling of Four Citrus Peel Cultivars via Ultra-Performance Liquid Chromatography Coupled with Quadrupole-Time-of-Flight-Mass Spectrometry and Multivariate Data Analyses.

Citrus plants are one of the most economical fruit bearing trees grown worldwide for their medicinal use as well as for the flavor and food industry. This study attempts to characterize the metabolome difference in polyphenols of four Citrus species fruit peels; C. reticulata Blanco cv. Egyptian, C. sinensis (L.) Osbeck cv. Olinda Valencia, C. aurantiifolia Swingle cv. Mexican and C. paradisi Macfad. cv. Duncan via ultra-performance liquid chromatography coupled with quadrupole-time-of-flight-mass spectrometry platform. A total of 163 metabolites were characterized of which 28 were detected for the first time in Citrus cultivars including eight coumarin derivatives, three cinnamic acids conjugates, one polymethoxyflavone, 5 O-glycosides, 2 C-glycosides, three flavone-di-O-glucosides and six acetyl sugar derivatives of luteolin and kaempferol in addition to oxygenated and methylated fatty acids. Flavonoids amounted for the most abundant secondary metabolites class in the studied Citrus peels. The relative variability among these Citrus peels was estimated using clustering analysis with flavonoids accounting for cvs. segregation. Hierarchical clustering analysis revealed the chemical similarity of C. reticulata, C. sinensis and C. paradise peels and being distant them from that of C. aurantiifolia. To the best of our knowledge, this study provides the first report for metabolite compositional differences in these four Citrus peels.

Daily Consumption of Orange Juice from Citrus sinensis L. Osbeck cv. Cara Cara and cv. Bahia Differently Affects Gut Microbiota Profiling as Unveiled by an Integrated Meta-Omics Approach.

We have investigated the effect of intake of two different orange juices from Citrus sinensis cv. "Cara Cara" and cv. "Bahia" on faecal microbiota and metabolome using an integrated meta-omics approach. Following a randomized crossover design, healthy subjects daily consumed 500 mL of orange juice from Cara Cara or Bahia juices or an isocaloric control drink. Stools were collected at baseline (T0) and after a week (T7) of intervention. Operational taxonomic units (OTUs) were pyrosequenced targeting 16S rRNA, and faecal metabolites were analyzed by an untargeted metabolomics approach based on 1H NMR spectroscopy. The major shift observed in microbiota composition after orange juice intake was the increased abundance of a network of Clostridia OTUs from Mogibacteriaceae, Tissierellaceae, Veillonellaceae, Odoribacteraceae, and Ruminococcaceae families, whose members were differently affected by Cara Cara or Bahia juice consumption. A core of six metabolites such as inositol, choline, lysine, arginine, urocanic acid, and formate significantly increased in Cara Cara compared to the Bahia group.

Effects of Postharvest Time, Heat Treatment, pH and Filtration on the Limonin Content in Newhall Navel Orange (Citrus sinensis Osbeck cv. Newhall) Juice

Delayed bitterness causes severe economic loss in citrus juice industry worldwide, which is mostly due to the formation of limonoid compounds, especially limonin, in juice. In this study, effects of postharvest time of fruits, heat treatment, pH and filtration of juice on limonin content in Newhall navel orange (Citrus sinensis Osbeck cv. Newhall) juice were investigated. Our research indicated for the first time that: (1) limonin content in juice would gradually increase to a maximal level and then remained almost constant thereafter as storage time going on, whereas the maximum constant value (MCV) of limonin content in juice significantly (p < 0.05) decreased with the increment of postharvest time of fruits being juiced; (2) heat treatment and acidification of juice only speeded up the formation of limonin to the maximal level while without changing the MCV of limonin content; (3) the juice after filtration exhibited much lower MCV of limonin content compared with the unfiltered one. These experimental observations might not only provide useful information for the development of new debitterness method for navel orange juice, but also strongly support the acid-promoted delayed bitterness mechanism, suggesting the formation of delayed bitterness might primary due to the acid-promoted rather than the enzyme-catalyzed lactonization of limonoate A-ring lactone (LARL) to produce limonin in juice of navel orange.

CHEMICAL COMPOSITION OF VOLATILE COMPONENTS IN THE LEAVES OF CITRUS PLANTS CULTIVATED UNDER GREENHOUSE CONDITIONS

The article presents the results of research of the chemical composition of easily volatile components in the leaves of nine taxa representing species and varieties of the genus Citrus L. cultivated under the conditions of greenhouses of the Central Botanical Garden of the National Academy of Sciences of Belarus as: C. unshiu (Tanaka ex Swingle) Marcow., C. grandis Osbeck cv. Bogatyr, C. sinensis Osbeck cv. Washington Navel, C. medica L. cv. Sarcodactilis, C. medica cv. Pavlovskiy Shishkan, Lemon Skernevitsky (’Ponderosa lemon’) is a clone of the hybrid C. medica L. × C. limon (L.) Burm. f., Citrofortunella microcarpa, C. limon (L.) Osbeck cv. Pavlovskiy, C.meyeri (Ju. Tanaka). The volatile components were extracted using a Supelco™ solid-phase microextractor placed in the vapour-air space above air-dried, finely ground and heated to 40 °C leaf samples. The component composition of the extracts was analyzed by the GC/MS method using the Agilent Technologies 6850 Series II system (Network GC System/5975B (VL MSD). Total 36 components were identified in the leaves of citrus plants: monoterpenes (14), sesquiterpenes (11), and oxygen-containing compounds: terpene alcohols, aldehydes, ethers (11). The studies have shown that the cyclic hydrocarbons monoterpene (Z)-β-trans-Ocimene and 3 sesquiterpenes (β-caryophyllene, (3E, 6E)-α-farnesene, and α-caryophyllene) were detected in the volatile components in leaves in the whole citrus group. While 2 sesquiterpenes: (3E,6E)-α-farnesene and α-caryophyllene are dominant for the most taxa based on their proportions in the total volume of volatile compounds. Sesquiterpene beta-Elemene is present as a dominant component exclusively in species and varieties representing the so-called “sweet citrus” group as it follows from the results of the studies: C. unshiu, C. grandis cv. Bogatyr, C. sinensis× cv. Washington Navel, C. meyeri, which allows one to consider it as a significant feature in the taxonomy of the genus Citrus L.

Performance of ‘Cadenera’ orange trees grafted on five rootstocks

Abstract Citriculture is an important alternative for the agribusiness development in the state of Paraná, Brazil. However, the use of a few cultivars of scion and rootstock restricts the harvest period and increases the vulnerability to pests and diseases. This study aimed to evaluate the vegetative growth, production and fruit quality of ‘Cadenera’ orange trees (Citrus sinensis (L.) Osbeck ) grafted on five rootstocks, during nine harvests, under a subtropical environmental condition. The experimental design was randomized blocks with six replications, two plants per plot, and five rootstocks: ‘Rangpur’ lime (C. limonia Osb.), ‘Cleopatra’ (C. reshni hort. ex Tanaka ) and ‘Sunki’ mandarins (C. sunki hort. ex Tanaka (L.) Raf.), ‘Swingle’ citrumelo [C. paradisi Macfad. x Poncirus trifoliata (L.) Raf.], and ‘C-13’ citrange [C. sinensis (L.) Osbeck cv. Pera x P.s trifoliata (L.) Raf.]. Biometric variables, and fruit yield and quality were analyzed. The smallest canopy size was induced by ‘Rangpur’ lime and ‘C 13’ citrange rootstocks. ‘Swingle’ citrumelo and ‘C 13’ citrange provided the highest yields for the ‘Cadenera’ sweet orange trees and were superior to ‘Rangpur’ lime. Trees grafted on ‘C 13’ citrange presented the highest yield and productive efficiency.

Chemical composition and antimicrobial activity of Gannan navel orange (Citrus sinensis Osbeck cv. Newhall) peel essential oils.

The present investigation reported the chemical composition of cold pressed Gannan navel orange peel essential oil (EO) and its molecular distillation fraction (light phase EO), and examined their antimicrobial activity against spoiling and pathogenic microorganisms. Gas chromatography‐mass spectrometry analysis identified 27 and 20 different chemical constituents in cold pressed EO and light phase EO, respectively. Limonene was the major constituent, accounting for 85.32% of cold pressed EO and 60.44% of light phase EO. Both EOs and some of their constituents showed good antimicrobial activity. Compared to cold pressed EO, light phase EO exhibited the better antimicrobial activity under weak acidic and neutral conditions. The light phase EO presented a higher antimicrobial activity after thermo‐treatment at 60–100°C for 20 min than cold pressed EO. These results demonstrated that light phase EO had a potential to be used as a novel antimicrobial agent for food preservation and food processing.

Characterization and selection of Citrus sinensis Osbeck cv. Margaritera parental trees for repopulation in the Mompox depression region, Colombia

At the Mompox depression region, located in the lower valley of the Magdalena River, citrus trees and especially the orange cultivar Margaritera (Citrus sinensis Osbeck) are cultivated by small producers. The effects of the rainy season during 2010 and 2011 caused the loss of ca. 80% of the planted area in some municipalities. The main objective of this study was to select outstanding genotypes according to fruit quality attributes based on the Colombian Technical Standard NTC4086. This selection was carried out by collecting and characterizing 120 Margaritera orange genotypes represented by three clones: Margarita, Azucar and Criollo. The characterization was performed using 14 fruit descriptors regulated by the parameters of the International Plant Genetic Resources Institute. Outstanding clones were chosen using a selection index based on attributes such as juice percentage and maturity index. The fruit characterization showed variability for all the descriptors evaluated, especially those related to size, weight and acidity (explained 51.76% of the total variability). Furthermore, these contributed mostly to comprise three phenotypic groups conformed by 79, 23 and 18 genotypes, respectively. Eight outstanding genotypes were selected for quality attributes: four Margarita clones, two Azucar clones and two Criollo clones; these became a source of guaranteed propagation material in the region.

Physicochemical stability of blood orange juice during frozen storage

ABSTRACTBlood orange juice from Citrus sinensis (L.) Osbeck cv. Moro was compared to a concentrated blood orange juice and both juices were studied during frozen storage at −20°C. Analyses were conducted on pH (3.33–3.81) and titratable acidity as citric acid (11.14–13.16 g/L). The formol number decreased in both blood orange juice and concentrated blood orange juice during frozen storage, while vitamin C showed a very slight decrease. Scavenging abilities of the juices for the DPPH∙ radical ranged from 53.39% to 42.55% in blood orange juice and from 39.16% to 33.75% in concentrated blood orange juice during frozen storage. Although anthocyanins showed a diminution during storage in both the concentrated and non-concentrated blood orange juice, they were always higher in the non-concentrated juice fruit. Four phenolic acids were detected: gallic, chlorogenic (the highest quantity, 13–27 mg/L), caffeic, and ferulic, the latter showed the lowest content. Ten flavonoids were identified, two flavonols (rutin and quercetin) and eight flavanones: narirutin (the second highest flavonoid), naringin, hesperidin (the highest quantity), neoeriocitrin, didymin, eriocitrin, neohesperidin, and hesperetin. Concentration and duration of frozen storage were found to influence the physicochemical properties of blood orange juice in different ways.

Characterization and Purification of Bergamottin from Citrus grandis (L.) Osbeck cv. Yongjiazaoxiangyou and Its Antiproliferative Activity and Effect on Glucose Consumption in HepG2 cells.

Bergamottin is a natural furanocoumarin compound with weak polarity. Characterization and quantification of bergamottin were carried out in different fruit tissues of various citrus cultivars. Among the four citrus tissues tested, i.e., flavedo, albedo, segment membrane (SM), and juice sacs (JS) in eight citrus cultivars, the highest bergamottin content was found in the flavedo of Citrus grandis (L.) Osbeck cv. Yongjiazaoxiangyou (YJZXY, 666.54 μg·g−1 DW). A combination of silica gel column chromatography and high-speed counter-current chromatography (HSCCC) was established to efficiently purify bergamottin from the flavedo of YJZXY. Bergamottin showed significant antiproliferative activity on three cancer cell lines, i.e., human liver cancer HepG2, promyelocytic leukemia HL-60, and gastric cancer BGC-823 cells, which showed a marked inhibition effect on these cell lines in a dose-dependent manner. In addition, bergamottin significantly increased glucose consumption in HepG2 cells also in a dose-dependent manner, which is the first report of its potential in anti-diabetes applications.

Fruit flavonoid variation between and within four cultivated Citrus species evaluated by UPLC-PDA system

Citrus fruits are rich in flavonoids and well-recognized for their health values. In order to describe the flavonoid characters of a citrus fruit type accurately, the flavonoid in fruits (peels and pulps) of four most commonly cultivated Citrus species represented by sweet orange (Citrus sinensis Osbeck cv. Newhall), lemon (C. limon Burm.f. cv. Eureka), pummelo (C. grandis Osbeck cv. Liangpingyou) and tangerine (C. tangerina Tanaka cv. Dahongpao), respectively, were studied using a new UPLC-PDA method. In this study, the results showed that different cultivated species were characterized by different dominant flavonoid compounds, such as naringin, erocitrin and hesperidin were the most predominant components of pummelo, lemon, mandarin and sweet orange, respectively. Nine polymethoxylated flavones (PMFs) were identified in the peels of sweet orange and mandarin using this new method, and nobiletin was proved to be the most dominant one. The flavonoid contents varied obviously among different fruit samples even collected from the same production area and the same cultivars. However, it is important to note that all the samples of the same cultivated species grouped in the same cluster in three dimensional scatter plots of principal components analysis (PCA). This study emphasized that the UPLC-PDA method is a simple, rapid and accurate method for citrus flavonoids analysis.