Lipid-dissolved γ-carotene, β-carotene,and lycopene in globular chromoplasts of peach palm (Bactris gasipaes Kunth) fruits

Main conclusion

High levels of β-carotene, lycopene, and the rare γ-carotene occur predominantly lipid-dissolved in the chromoplasts of peach palm fruits. First proof of their absorption from these fruits is reported. The structural diversity, the physical deposition state in planta, and the human bioavailability of carotenoids from the edible fruits of diverse orange and yellow-colored peach palm (Bactris gasipaes Kunth) varieties were investigated. HPLC–PDA–MSⁿ revealed a broad range of carotenes, reaching total carotenoid levels from 0.7 to 13.9 mg/100 g FW. Besides the predominant (all-E)-β-carotene (0.4–5.4 mg/100 g FW), two (Z)-isomers of γ-carotene (0.1–3.9 mg/100 g FW), and one (Z)-lycopene isomer (0.04–0.83 mg/100 g FW) prevailed. Approximately 89–94 % of total carotenoid content pertained to provitamin A carotenoids with retinol activity equivalents ranging from 37 to 609 µg/100 g FW. The physical deposition state of these carotenoids in planta was investigated using light, transmission electron, and scanning electron microscopy. The plastids found in both orange and yellow-colored fruit mesocarps were amylo-chromoplasts of the globular type, containing carotenoids predominantly in a lipid-dissolved form. The hypothesis of lipid-dissolved carotenoids was supported by simple solubility estimations based on carotenoid and lipid contents of the fruit mesocarp. In our study, we report first results on the human bioavailability of γ-carotene, β-carotene, and lycopene from peach palm fruit, particularly proving the post-prandial absorption of the rarely occurring γ-carotene. Since the physical state of carotenoid deposition has been shown to be decisive for carotenoid bioavailability, lipid-dissolved carotenoids in peach palm fruits are expected to be highly bioavailable, however, further studies are required.     

Biological control of the oil palm pestLatoia viridissima [Lepidoptera,limacodidae], in Cote d'Ivoire,by a new picornavirus

Among the major oil palm pest insects in the Côte d'Ivoire,Latoia viridissima Holland [Lepidoptera, Limacodidae] is the most frequently observed defoliator. During a pullulation of this species, a natural epizootic permitted us to demonstrate the occurrence of a small isometric RNA virus of 30nm in diameter. The buoyant density of the virus particles was 1.34. The virus capsid contained 2 major proteins with molecular weights of 30,000 (55%) and 31,000 (20%) and 3 minor proteins. One genome component was detected with molecular weight 2,9×10⁶. Agarose gel diffusion tests showed this virus was distinct from any other described insect Picornavirus. Trials with different doses of viral suspensions were tested on industrial oil palm plantation, allocated byL. viridissima, from ground level, using an automatic air carried sprayer. One week after the treatment, a mortality gradient, increasing from 11 to 61% according to the dose applied, was obtained. Two weeks after the treatment the mortality reached 92% of the larvae in the treated parcels. During the next generation, the number of caterpillars on the same parcel was very low.     

Effects of rearing conditions on the parasitism of Tetrastichus brontispae on its pupal host Octodonta nipae

Octodonta nipae (Maulik) (Coleoptera: Chrysomelidae) is currently a serious invasive pest of palm plants in southern China. Although previous studies reported that Tetrastichus brontispae Ferriere (Hymenoptera: Eulophidae) could successfully parasitize the pupae of O. nipae, little is known of the potential for T. brontispae to control this pest. To understand the interaction between T. brontispae and O. nipae, the effects of parasitoid feeding regimes, host age and density, parasitoid age and density, and cold storage on the parasitism of T. brontispae were investigated. Our results indicate that a supply of either glucose or sucrose increased the longevity and fecundity of T. brontispae. The parasitoid preferred one-day-old host pupae and its fecundity increased with increasing host or parasitoid female density. Extended cold storage negatively affected the parasitism of T. brontispae. These results demonstrate how to efficiently raise T. brontispae and will contribute to the effective management of O. nipae.     

The influence of EDTA on the composition of alginate synthesized by Azotobacter vinelandii

1. During an investigation of the physiology of Azotobacter vinelandii with particular reference to polysaccharide formation, a suitable medium which was precipitate-free was developed by adding EDTA at a concentration of 50 mg/l to a basal medium containing one of eight different carbohydrates as sole carbon source.
2. Acetylated alginate was always produced by the organism when cultured under defined conditions, regardless of the carbohydrate source incorporated in the basal medium.
3. When EDTA was added to the medium, the bacteria produced acetylated polyuronides with a preponderance of mannuronic acid residues.
4. A comparison of the infrared spectra of the alginate produced by Azotobacter vinelandii and the affect of EDTA upon the mannuronic acid/guluronic acid ratios of the alginate are reported.

     

Molluscicidal activity of the Puerto Rican Weed,Solatium nodiflorum,against snail hosts ofFasciola hepatica

After screening 200 species of Puerto Rican plants, Solanum nodiflorumwas selected for comprehensive laboratory evaluation as a source of natural molluscicide. All parts of this plant were found toxic to the snails Fossaria (Lymnaea) cubensis, Lymnaea columella, Biomphalaria glabrata,and Physa cubensis.No toxicity was found against Marisa cornuarietisand Tarebia granifera. The toxicant was not affected by pH and dry storage. There was a direct correlation between temperature and molluscicidal activity. The plant is easy to find locally and could be developed into cheap, safe means for controlling both Schistosomaand Fasciolasnail hosts in Puerto Rico.     

Identification of hypervariable regions within the 16S–23S rRNA intergenic spacer region of Flavobacterium columnare and its application in assigning genomovar group to an individual strain

Flavobacterium columnare is an important bacterial pathogen of fish with a wide genetic variability within the species. This intra-species diversity has been termed as genomovars and genomovar groups on the basis of Restriction Fragment Length Polymorphisms of 16S rDNA and 16S–23S rDNA intergenic spacer region (ISR), respectively. In this study, we demonstrate the source of genetic heterogeneity in the F. columnare by sequence analysis of ISR. The length of ISR sequences of different genomovars varied from 553 to 592 nucleotides, while the similarity among sequences ranged from 76.1 to 92.6%. A common ISR structure with tRNA^Ala and tRNA^Ile embedded within the sequence was identified in all the genomovars of F. columnare. The results show that strains of F. columnare can be categorized into five genomovar groups based on the heterogeneity of the ISR sequences. Of these, strains belonging to Genomovar I and II can be sub-divided into two groups each; while strains of Genomovar III belong to one group. Sequence similarity between genomovar groups was lower for ISR (76.1–92.6%) as compared to 16S rDNA (96.1–99.4%) indicating its ability to resolve closely related groups within the genomovars of F. columnare. The main source of variation between the genomovar groups is the presence of three hyper variable regions (V1, V2, and V3) in the ISR. Of the three, V3 was found to be the most heterogeneous region and was found to be useful in assigning a genomovar group to an individual strain of F. columnare.     

Glyoxylate conversion by Hyphomicrobium species grown on allantoin as nitrogen source

Glyoxylate, formed as a result of allantoin degradation, is converted by Hyphomicrobium species to glycerate via tartronate semialdehyde. Glyoxylate carboligase and tartronate semialdehyde reductase, the two enzymes involved, are present only in cells grown on allantoin as nitrogen source.     

Zearalenone degradation by two Pseudomonas strains from soil

This study describes the screening of soil bacteria for their capability to degrade zearalenone (ZEN), employing an enrichment technique in which ZEN is used as the sole carbon source. Two isolates that were able to degrade ZEN belonged to the genus Pseudomonas according to biochemical characterization and 16S rRNA gene sequence and were named as Pseudomonas alcaliphila TH-C1 and Pseudomonas plecoglossicida TH-L1, respectively. The results showed that the degradation rates of P. alcaliphila TH-C1 and P. plecoglossicida TH-L1 for ZEN (2 μg/ml) were 68?±?0.85 % and 57?±?0.73 %, when incubated for 72 h at 30 °C in a rotary shaker (160 rpm) and detected by high-performance liquid chromatograms (HPLC). These results suggest that the two Pseudomonas strains are new bacterial resource for degrading ZEN and can provide a new approach for the detoxification of ZEN.     

Sayl andghayl: The ecology of water allocation in Yemen

In this article, comparison is made between the two major types of water allocation systems in Yemen: seasonal flood (sayl)and highland spring flow (ghayl).Constraints in the nature of water as a flowing resource are defined for each system. The major distinctions between the two types of systems are variability in water flow (which influences the determination of access rights), techniques of water control, measurement of water turns, the need for supervision of irrigation activities, and the potential for economic expansion of the production system. It is argued that tribal political organization is an adaptive response to highland spring flow allocation in Yemen, but undergoes stress in coastal flood systems where competition for the same water source extends across tribal boundaries in upstream-downstream conflict.     

Double Transgenesis of Humanized fat1 and fat2 Genes Promotes Omega-3 Polyunsaturated Fatty Acids Synthesis in a Zebrafish Model

Omega-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are essential nutrients for human health. However, vertebrates, including humans, have lost the abilities to synthesize EPA and DHA de novo, majorly due to the genetic absence of delta-12 desaturase and omega-3 desaturase genes. Fishes, especially those naturally growing marine fish, are major dietary source of EPA and DHA. Because of the severe decline of marine fishery and the decrease in n-3 LC-PUFA content of farmed fishes, it is highly necessary to develop alternative sources of n-3 LC-PUFA. In the present study, we utilized transgenic technology to generate n-3 LC-PUFA-rich fish by using zebrafish as an animal model. Firstly, fat1 was proved to function efficiently in fish culture cells, which showed an effective conversion of n-6 PUFA to n-3 PUFA with the n-6/n-3 ratio that decreased from 7.7 to 1.1. Secondly, expression of fat1 in transgenic zebrafish increased the 20:5n-3 and 22:6n-3 contents to 1.8- and 2.4-fold, respectively. Third, co-expression of fat2, a fish codon-optimized delta-12 desaturase gene, and fat1 in fish culture cell significantly promoted n-3 PUFA synthesis with the decreased n-6/n-3 ratio from 7.7 to 0.7. Finally, co-expression of fat1 and fat2 in double transgenic zebrafish increased the 20:5n-3 and 22:6n-3 contents to 1.7- and 2.8-fold, respectively. Overall, we generated two types of transgenic zebrafish rich in endogenous n-3 LC-PUFA, fat1 transgenic zebrafish and fat1/fat2 double transgenic zebrafish. Our results demonstrate that application of transgenic technology of humanized fat1 and fat2 in farmed fishes can largely improve the n-3 LC-PUFA production.     

Prey range of the predatory ladybird Cryptolaemus montrouzieri

The prey range of Cryptolaemus montrouzieri was studied in the laboratory to investigate whether the mealybug destroyer can contribute to the suppression of other pest insects besides mealybugs and to assess its potential impact on non-mealybug populations as part of an environmental risk assessment for its use in biological control. Prey tested in these experiments were: tobacco aphid Myzus persicae nicotianae (Sulzer)(Hemiptera: Aphididae), pea aphid Acyrthosiphon pisum (Harris)(Hemiptera: Aphididae), tobacco whitefly Bemisia tabaci (Gennadius)(Hemiptera: Aleyrodidae), southern green stinkbug Nezara viridula (L.)(Hemiptera: Pentatomidae) eggs, western flower thrips Frankliniella occidentalis (Pergande)(Thysanoptera: Thripidae), two-spotted ladybird Adalia bipunctata (L.)(Coleoptera: Coccinellidae) eggs and eggs of the greater wax moth Galleria mellonella L. (Lepidoptera: Pyralidae). Larval survival was high to moderate when C. montrouzieri was provided with hemipteran prey and poor to zero when the ladybirds were provided with non-hemipteran prey. Females reared on M. persicae and A. pisum produced similar numbers of eggs as their counterparts fed the citrus mealybug Planococcus citri (Risso)(Hemiptera: Pseudococcidae), but fecundity was significantly lower when the ladybirds were reared on B. tabaci nymphs or on A. bipunctata eggs. Prey species that were found to be less suitable for immature development of C. montrouzieri could still be an adequate food source for reproduction and survival of adult ladybirds. For example, only 8 % of the predator larvae reached the adult stage when provided with A. bipunctata eggs, but females that had developed on eggs of the Mediterranean flour moth Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) and that were supplied with A. bipunctata eggs from adult emergence on, were only 35 % less fecund than females provided with mealybugs in their adult life. The results are discussed in relation to the development of a suitable methodology for prey/host range testing in the framework of an environmental risk assessment for arthropod natural enemies.     

A genome-wide detection of copy number variation using SNP genotyping arrays in Beijing-You chickens

Copy number variation (CNV) has been recently examined in many species and is recognized as being a source of genetic variability, especially for disease-related phenotypes. In this study, the PennCNV software, a genome-wide CNV detection system based on the 60 K SNP BeadChip was used on a total sample size of 1,310 Beijing-You chickens (a Chinese local breed). After quality control, 137 high confidence CNVRs covering 27.31 Mb of the chicken genome and corresponding to 2.61 % of the whole chicken genome. Within these regions, 131 known genes or coding sequences were involved. Q-PCR was applied to verify some of the genes related to disease development. Results showed that copy number of genes such as, phosphatidylinositol-5-phosphate 4-kinase II alpha, PHD finger protein 14, RHACD8 (a CD8α- like messenger RNA), MHC B-G, zinc finger protein, sarcosine dehydrogenase and ficolin 2 varied between individual chickens, which also supports the reliability of chip-detection of the CNVs. As one source of genomic variation, CNVs may provide new insight into the relationship between the genome and phenotypic characteristics.     

Feeding behavior and diet of the eight-banded butterflyfish Chaetodon octofasciatus in the Thousand Islands,Indonesia

Marine fishes reach their highest diversity in coral reef ecosystems, which they utilize as territory, place of refuge and reproduction, and source of food. One type of predation among reef fishes is feeding on coral polyps, and a single, easily identifiable family of fishes, Chaetodontidae, contains the majority of obligate corallivore species. Multiple studies have examined the behaviour and ecology of Chaetodontidae and their relationship with the benthic habitat. However, many questions remain about their feeding ecology and food specifity at the species level. The present study is the first attempt to systematically decipher the feeding behavior of the obligate corallivore, Chaetodon octofasciatus. Field data were collected from four sites in the Thousand Islands, Indonesia, during two sampling campaigns in 2006, covering two seasons and two different depths. A high abundance of C. octofasciatus was positively related to hard coral cover. Out of a total of 57 scleractinian coral genera observed during the study period, 24 were utilized by C. octofasciatus. All fish collected during the study (n?=?36) had >86 % nematocysts in their guts, supporting their classification as obligate corallivores. Based on the Strauss electivity index, C. octofasciatus displayed a preference for the coral genus Acropora at all depths, while preference for Fungia became more marked at greater depth. Both Acropora and Fungia were observed at high density at all sites, with Acropora density decreasing markedly with depth and Fungia density increasing. Bite rates showed an asymptotic relationship to Acropora density, levelling off between 15 and 20 bites/5 min. The existence of a strong relationship with live coral cover and the preference for specific genera such as Acropora designate C. octofasciatus as a potential bioindicator in the Thousand Islands reefs, while making it particular susceptible to the ongoing degradation of reefs in the region.     

NaturalMycoplasma arthritidis infection in mice

B6C3F₁ mice from a hybrid production colony frequently were serologically positive by enzyme-linked immunosorbent assay (ELISA) and consistently negative by culture forMycoplasma pulmonis. Subsequently, 162 mice were obtained and intensively studied using an expanded group of cultural procedures, ELISA, and histopathology. Lesions attributable to mycoplasma infection were not found, butMycoplasma arthritidis was isolated from 20 mice. TheM. pulmonis ELISA was positive (IgM, IgG, or both) in 113 mice. Selected sera were tested simultaneously in both theM. pulmonis ELISA and in an ELISA usingM. arthritidis antigen, and were found to be positive in both the IgM and IgG classes in both ELISAs. Thus, cross-reacting antibody was produced in mice naturally infected withM. arthritidis, confirming previous observations based on experimental infections. To our knowledge, this is the first report of naturalM. arthritidis infection in laboratory mice.