Chemical and biological assessment of high value pharmaceutical raw material from Egyptian orange peel

In Egypt, orange juice industries generate huge amount of waste peel that could be a source of raw materials with high value and economic return. Here, we explored a better model for waste management of citrus processing waste in Egypt by developing an ecofriendly method for preparation of value added materials. A high grade pectin (HGP) was obtained from the crude acidic water extract of the peel after passing through Diaion HP20 column. The HGP showed potent antidiabetic activity at lower dose than those reported in literature. It possessed significant effect on blood glucose (BG) level, as well as parameters relevant to liver and kidney functions in streptozotocin (STZ) induced diabetic rats. On the other hand, the essential oil (EO) prepared by cold press showed the highest yield (0.72% w/w) and it is the most applicable method of isolate orange oil on pilot scale. EO showed significant antimicrobial activity against the tested food borne pathogens. In conclusion, high value materials — HGP and EO were prepared on pilot scale from the waste orange peel. While the HGP can be included in food supplement for diabetic patients, EO can be used as a natural food preservative.

Potential of X-ray imaging to detect citrus granulation in different cultivars with progress in harvesting time

Granulation, a physiological disorder of citrus is manifested by shriveled juice sacs and internal dryness. Extractable juice in granulated tissue is drastically reduced as a consequence of gelatinization and secondary epidermis formation. Since, the defect cannot be detected externally it leads to consumer dissatisfaction and poor returns to farmers. Processing industry also faces huge economic loss due to reduction in the juice recovery from granulated fruit. In this context, here, we studied the possibility of developing an image processing algorithm through MATLAB software to detect granulation with advancement of maturity via X-ray micrographs. Fruit of eight citrus cultivars comprising of granulation susceptible and tolerant varieties harvested at four different intervals were exposed to X-rays. Voltage of 46 kV and current of 6.5 mA given to fruit for an exposure time of 320 mAs gave the best X-ray image contrasts. The developed algorithm could effectively distinguish the healthy and granulated fruit with an accuracy of 90% as validated by subsequent destructive analysis when estimated for four different harvesting dates. The imaging technique can be employed by the processors to determine the severity of granulation and to sort out fruit online which will help in saving economic losses.

Genomewide analysis of the CIII peroxidase family in sweet orange (Citrus sinensis) and expression profiles induced by Xanthomonas citri subsp. citri and hormones

Class III peroxidase (CIII prx) is a plant-specific multigene family that regulates the physiological and stress responses. This research aimed to exhaustively annotate and analyse the CIII prx family in sweet orange and to explore the regulated expression profiles by Xanthomonas citri subsp. citri (Xcc) and plant hormones. We further assessed the relationship between CIII prxs and citrus bacterial canker. The phylogeny, gene structure, conserved motifs, gene duplications and microsynteny of the CIII prx family were analysed. Expression profiles of specific CsPrxs induced by Xanthomonas citri subsp. citri and plant hormones were detected by quantitative reverse transcription-polymerase chain reaction. Subcellular localization was analysed through transient expression assessments. A total of 72 CIII prx members were identified from the genomes of sweet orange. In all chromosomes of sweet orange, the CsPrxs could be detected except in chromosome 8. In addition, three segmental duplications, four tandem duplications and 11 whole-genome duplications occurred among the CsPrxs, contributing to the family size expansion. From the Ka/Ks ratios, 15 of 18 duplicated CsPrxs pairs have experienced purifying selection process. A total of 15 conserved motifs were detected in CsPrxs, four of which were detected in all complete CsPrxs. A total of 12 expressed genes were identified from the EST database. The expression trends of 12 CsPrxs were differently expressed at different stages of infection by Xcc, five of which were potential candidate genes involved in Xcc resistance. These genes could be induced by salicylic acid and methyl jasmonate, and were extracellular proteins. These results further support our understanding of CIII prxs in citrus, particularly in citrus bacterial canker studies

Effect of Maltodextrin Concentration and Inlet Air Temperature on Properties of Spray Dried Powder from Reverse Osmosis Concentrated Sweet Orange Juice

Abstract Sweet orange juice is an important part of diet since it is nutritious beverage offering good taste and play significant part in a healthy diet. High hygroscopicity, thermo-plasticity and presence of low molecular weight components in sweet orange juice offer low glass transition temperature (Tg), likely to form soft particle with sticky surface leading to sticky powder during drying. Maltodextrins are amorphous drying aids that tend to inhibit sugar crystallization and form a high Tg product after drying. In this study, the effect of the different spray drying parameters on the quality of powder derived from control and concentrated juice at three inlet air temperatures 120, 130 and 140 °C and at three levels of juice total soluble solids (TSS): maltodextrin levels at 1:0.5; 1:1 and 1:1.5 were studied. The impact of inlet air temperature and maltodextrin concentration has significantly affected various properties of sweet orange powder. For control juice, process yields increased with increase in inlet air temperature and maltodextrin concentration. However, for reverse osmosis (RO) concentrate, process yield increased with increase in maltodextrin concentration and decreased with increase in inlet air temperature. For control juice, process yields obtained were in the range of 12.59-41.16% and in case of concentrated juice, the process yield obtained was in the range of 21.35-56.95% at different combinations of inlet air temperature and maltodextrin concentrations. Spray-dried powder was considered as "possible" and "fair" in terms of flowability and cohesiveness. Vitamin C retention was high at lower inlet air temperature with lower concentration of maltodextrin.

Diversidade de moscas-das-frutas em pomares de citros no município de Araruama, RJ / Diversity of fruit flies in citrus groves in the municipality of Araruama, RJ

O objetivo deste estudo foi determinar as espécies de Tephritidae e Lonchaeidae (Diptera: Tephritoidea) de ocorrência em pomares de laranja doce (Citrus sinensis Osbeck) e tangerina (Citrus reticulata Blanco), no município de Araruama, RJ, durante o período de dezembro de 2002 a novembro de 2003. Os espécimes foram coletados em armadilhas McPhail contendo solução aquosa de proteína hidrolisada a 5 por cento e em amostras de frutos de seis variedades de citros. Nas armadilhas, o total de 2.543 adultos de Tephritoidea (1.430 fêmeas e 1.023 machos) foi capturado, sendo dez espécies de Tephritidae, quatro espécies e dois morfotipos de Lonchaeidae. Dos Tephritidae e capturados nas McPhail, quatro espécies (Anastrepha fraterculus, A. obliqua, A. sororcula e Ceratitis capitata) infestaram frutos cítricos, enquanto que, dos Lonchaeidae, somente os morfotipos não infestaram as amostras de citros. Os resultados demonstram que a densidade populacional das moscas-das-frutas pode ser superestimada, quando baseada no número de moscas por armadilha, devido à captura de espécies que não infestam os frutos de interesse comercial.

This study was aimed at determining the species of Tephritidae and Lonchaeidae (Diptera: Tephritoidea) that occur on groves of sweet orange (Citrus sinensis Osbeck ) and tangerine (Citrus reticulata Blanco) in the municipality of Araruama, state of Rio de Janeiro, Brazil, from December, 2002 to November, 2003. The specimens were collected by McPhail traps with aqueous solution of hydrolyzed protein to 5 percent and in fruits samples of six varieties of citrus. In the traps the total of 2,543 adults of Tephritoidea (1,430 females and 1,023 males) was captured, being ten species of Tephritidae, four species and two morphotypes of Lonchaeidae. From the Tephritidae caught by the McPhail, four species (Anastrepha fraterculus, A. obliqua, A. sororcula and Ceratitis capitata) infested citric fruits while the Lonchaeidae, the morphotypes did not infest the citrus. The results showed that the population density of fruit flies may be overestimated when based on the number of flies per trap due to the capture of species that not infest the fruits of commercial interest.

An in silico analysis of the key genes involved in flavonoid biosynthesis in Citrus sinensis

Citrus species are known by their high content of phenolic compounds, including a wide range of flavonoids. In plants, these compounds are involved in protection against biotic and abiotic stresses, cell structure, UV protection, attraction of pollinators and seed dispersal. In humans, flavonoid consumption has been related to increasing overall health and fighting some important diseases. The goals of this study were to identify expressed sequence tags (EST) in Citrus sinensis (L.) Osbeck corresponding to genes involved in general phenylpropanoid biosynthesis and the key genes involved in the main flavonoids pathways (flavanones, flavones, flavonols, leucoanthocyanidins, anthocyanins and isoflavonoids). A thorough analysis of all related putative genes from the Citrus EST (CitEST) database revealed several interesting aspects associated to these pathways and brought novel information with promising usefulness for both basic and biotechnological applications.

Citrus plastid-related gene profiling based on expressed sequence tag analyses

Plastid-related sequences, derived from putative nuclear or plastome genes, were searched in a large collection of expressed sequence tags (ESTs) and genomic sequences from the Citrus Biotechnology initiative in Brazil. The identified putative Citrus chloroplast gene sequences were compared to those from Arabidopsis, Eucalyptus and Pinus. Differential expression profiling for plastid-directed nuclear-encoded proteins and photosynthesis-related gene expression variation between Citrus sinensis and Citrus reticulata, when inoculated or not with Xylella fastidiosa, were also analyzed. Presumed Citrus plastome regions were more similar to Eucalyptus. Some putative genes appeared to be preferentially expressed in vegetative tissues (leaves and bark) or in reproductive organs (flowers and fruits). Genes preferentially expressed in fruit and flower may be associated with hypothetical physiological functions. Expression pattern clustering analysis suggested that photosynthesis- and carbon fixation-related genes appeared to be up- or down-regulated in a resistant or susceptible Citrus species after Xylella inoculation in comparison to non-infected controls, generating novel information which may be helpful to develop novel genetic manipulation strategies to control Citrus variegated chlorosis (CVC).

Analysis of expressed sequence tags from Citrus sinensis L. Osbeck infected with Xylella fastidiosa

In order to understand the genetic responses resulting from physiological changes that occur in plants displaying citrus variegated chlorosis (CVC) symptoms, we adopted a strategy of comparing two EST libraries from sweet orange [Citrus sinensis (L.) Osbeck]. One of them was prepared with plants showing typical CVC symptoms caused by Xylella fastidiosa and the other with non-inoculated plants. We obtained 15,944 ESTs by sequencing the two cDNA libraries. Using an in silico hybridization strategy, 37 genes were found to have significant variation at the transcriptional level. Within this subset, 21 were up-regulated and 16 were down-regulated in plants with CVC. The main functional categories of the down-regulated transcripts in plants with CVC were associated with metabolism, protein modification, energy and transport facilitation. The majority of the up-regulated transcripts were associated with metabolism and defense response. Some transcripts associated with adaptation to stress conditions were up-regulated in plants with CVC and could explain why plants remain alive even under severe water and nutritional stress. Others of the up-regulated transcripts are related to defense response suggesting that sweet orange plants activate their defense machinery. The genes associated with stress response might be expressed as part of a secondary response related to physiological alterations caused by the infection.

Differentially expressed stress-related genes in the compatible citrus-Citrus leprosis virus interaction

Leprosis, caused by Citrus leprosis virus, cytoplasmic type (CiLV-C), is the main viral disease in the Brazilian citrus industry. This occurs because of the widespread source of inoculum and the year-round presence of the vector, the tenuipalpid mite Brevipalpus phoenicis, in citrus plants. In addition, while some Citrus species are resistant to CiLV-C, C. sinensis, the main cultivated species in the country, is extremely susceptible to the disease. The main objective of this work was to identify genes in C. sinensis cv. Pêra plants that were differentially expressed after the host was challenged with CiLV-C. In order to accomplish that, cDNA libraries were constructed from healthy and CiLV-inoculated sweet orange leaves. Two hundred and fifty-four genes were found to differ significantly in terms of expression, with 193 of them induced and 61 repressed after inoculation. Here we discuss the possible roles of a sub-set of these genes involved in metabolism, energy, signaling and cell rescue, defense and virulence, and indicate which kind of response may take place in the initial steps of the disease. Although the symptoms induced by CiLV-C in its compatible interaction with sweet orange resemble those of hypersensitive response (HR) in incompatible interactions, our data indicate that, apparently, the manifestation of leprosis symptoms should not be considered HR.