叶龄与摘花对黄秋葵叶黄素和β-胡萝卜素含量的影响

研究了叶龄与摘花两因子对黄秋葵018、024和0213品系的叶片叶黄素和β-胡萝卜素含量的影响。结果表明：018品系20d叶龄叶片的叶黄素和β-胡萝卜素含量最高,024品系30d叶龄叶片的叶黄素和β-胡萝卜素含量最高,021品系40d叶龄叶片的叶黄素和β-胡萝卜素含量最高;摘花处理降低了018和024品系叶片的叶黄素和β-胡萝卜素含量,却提高了021品系叶片的叶黄素和β-胡萝卜素含量。     

Cyanobacteria Secondary Metabolites as Biotechnological Ingredients in Natural Anti-Aging Cosmetics: Potential to Overcome Hyperpigmentation,Loss of Skin Density and UV Radiation-Deleterious Effects

The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O₂^•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O₂^•− scavenging, (IC₅₀ = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC₂₅ = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC₅₀ = 863 µg/mL; elastase, IC₅₀ = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O₂^•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.     

Effect of Phosphatidylcholine and Beta-Carotene Supplementation on Growth and Immune Response of Nile Tilapia,Oreochromis niloticus,in Cool Water

The effects of nutraceuticals in improving growth and immune response of Nile tilapia in cool water were investigated. Fish were reared in two different environments: warm water (28°C) and cool water (16°C). Fish reared in warm water (control) were provided with a basal commercial diet, while fish reared in cool water were provided with either the basal commercial diet (cool water control) or diets supplemented with nutraceuticals (either phosphatidylcholine or β-carotene). Experiments were conducted over an 8-week period. Fish held in warm water had significantly higher growth (p < 0.05), but condition factor, blood hematocrit, plasma glucose, and phagocytic capacity of macrophage cells were similar to fish held in cool water. Within the cool water groups (basal vs. supplemented diet), fish did not show any significant difference in condition factor, blood hematocrit, and phagocytic capacity of macrophage cells. Furthermore, there were no significant differences in glucose levels until the eighth week. Collectively these data indicate that a nutraceutical supplementation to the basal diet was not significantly beneficial. Despite slower growth, fish reared in cool water remained generally healthy. The observation that phagocytic capacity of macrophage cells was not significantly different suggests that disease resistance of tilapia grown in cool water may be comparable to those reared in warm water. Thus, our experiments suggest the feasibility of stocking or rearing tilapia in water temperatures as low as 16°C during cool weather, without need for supplementation to basal commercial feed.     

Phenotypic divergence in vegetable amaranth for total antioxidant capacity,antioxidant profile,dietary fiber,nutritional and agronomic traits

A lot of variations in vegetable amaranth germplasm have been observed in Bangladesh. It has been used as a cheap source of antioxidants, nutrients, protein, and dietary fiber. But no efforts had not been taken to know the status of antioxidant content, polyphenol, flavonoid, antioxidant vitamins and minerals, dietary fiber, nutritional and agronomic traits. In this study, Forty-three vegetable amaranth genotypes were evaluated to determine the status of total antioxidant content, polyphenol, flavonoid, antioxidant vitamins and minerals, dietary fiber, nutritional and agronomic traits and the magnitude of genetic diversity based on the contribution of those traits for meaningful grouping and proper utilization in future breeding program. The experiment was carried out in an open experimental field at Bangabandhu Sheikh Mujibur Rahman Agricultural University, Bangladesh in a randomized complete block design with three replications. Multivariate (Principal component and cluster) analysis was done using numerical taxonomic techniques of Sneath, & Sokal. Four principal components contributed 98.61% of the variation. Biological yield and total antioxidant content was strongly associated with their related all agronomic traits. Total flavonoid content had a higher contribution to total antioxidant capacity compared to vitamin and mineral antioxidants. Contribution of antioxidant profile and agronomic traits was the highest in diversity of vegetable amaranth. Both high and low yielding genotypes had a high antioxidant profile. Therefore, high yielding genotypes (From cluster VI) could be used directly as high antioxidant profile varieties and low yielding genotypes as a source of donor parents in hybridization program. Cluster analysis grouped the genotypes into six clusters. The diverse genotypes in different clusters were identified. Genotypes with desirable genes of one cluster hybridized with promising genotypes of other diverge clusters could facilitate the accumulation of favorable genes in hybrids.

Abbreviations: PCA: principal component analysis; PC: principal component; dw: dry weight; TFC: total flavonoid content; TAC: total antioxidant capacity; TPC: total polyphenol content; K: potassium; Ca: calcium; Mg: magnesium; Fe: iron; Mn: manganese; Cu: copper; Zn: zinc     

Nematicides induced changes in the chemical constituents of potato tubers

Changes in the chemical constituents of potato tubers grown under different concentrations of 3 synthetic organic nematicides (carbofuran, aldicarb and phorate) and a natural plant product (sawdust) were investigated. There were no significant differences in the specific gravity, dry matter and starch content of tubers from different treatments. A significant increase in the content of non-reducing and total sugars was observed in all the treatments. Nematicidal treatments had significant effects on reducing sugars, true protein, free amino acids, orthodihydroxy phenols, beta-carotene and ascorbic acid. Application of nematicides reduced the content of total phenolic compounds which is a desirable change from a processing viewpoint. Potatoes grown under different nematicidal treatments can be processed into chips and French fries as they contain permissible levels of reducing sugars required for these forms of processing.     

Effects of foliar Fe and Zn fertilizers on storage root Fe,Zn, and beta-carotene content of sweet potato (Ipomoea batatas L.)

Foliar sprays of iron (Fe) and zinc (Zn) fertilizers are effective in improving Fe and Zn concentrations in sweet potato. The objective of this experiment was to examine the effects of foliar fertilization with Fe and Zn in association with amino acids (AA) on Fe and Zn biofortification and the nutritional quality of sweet potato under both greenhouse and field conditions. Compared with treatment CK, foliar Fe, Zn, and Fe-Zn fertilizer applications could biofortify Fe and Zn concentrations and other nutrients in sweet potato to different extents. However, when 0.4% (wt/vol) AA was added to Fe-Zn fertilizer, the average Fe and Zn concentrations were increased by 70.2% and 59.8% under greenhouse conditions, and 52.9% and 43.7% under field conditions, respectively. The Fe-Zn-AA fertilizer application also resulted in incremental increases in root yield and beta-carotene content. This research identified some useful foliar fertilizers for accelerating Fe and Zn accumulation in selected sweet potato cultivars.     

Long-term fluctuations and effect of age on serum concentrations of certain fat-soluble vitamins in dairy cows

BACKGROUND: There is insufficient evidence in the literature concerning the fluctuations and correlations of serum fat-soluble vitamin concentrations during lactation in dairy cows and the potential effect of age of the animals on these values. OBJECTIVES: The objectives of this study were to determine fluctuations in mean serum concentrations of the fat-soluble vitamins A and E and b-carotene and the correlations among them in clinically healthy dairy cows, from the last month of the dry period until the end of lactation, and to investigate whether age was a factor that affects these serum concentrations. METHODS: Forty-five clinically healthy Holstein cows were assigned to 2 groups based on age. Group A consisted of 23 cows 4 years old (mean +/- SD, 3.24 +/- 0.44 years), and group B consisted of 22 cows >4 years old (6.68 +/- 1.66 years). Blood samples for determination of serum beta-carotene, vitamin A, and vitamin E concentrations were collected from each animal just before the start of study (1 month prior to expected parturition), at parturition, and thereafter, at monthly intervals until the end of lactation. RESULTS: There was a significant positive correlation between beta-carotene, vitamin A, and vitamin E values. Mean serum concentrations of beta-carotene, vitamin A, and vitamin E were significantly higher in younger animals. CONCLUSIONS: To our knowledge, this is the first evidence that age is a factor affecting serum concentrations of fat-soluble vitamins in dairy cows.     

β-胡萝卜素的吸收代谢及其影响因素研究

β-胡萝卜素作为一种类胡萝卜素,在动物营养和生理功能方面发挥着重要的作用。本文从β-胡萝卜素的生理功能、吸收、代谢等方面进行了总结。     

The usefulness of iron bioavailability as a target trait for breeding maize (Zea mays L.) with enhanced nutritional value

Iron (Fe) deficiency is the most widespread nutritional problem, affecting as many as half of the world's population. Only a small fraction (2-15%) of Fe from plant sources is typically bioavailable, that is, available for absorption and nutritionally useful for humans. This study evaluated Fe concentration and bioavailability for three diverse sets of 12, 14 and 16 maize hybrids grown in two- or three-location trials to assess the feasibility of selecting for Fe bioavailability in breeding programs. Bioavailability of Fe, assessed using the in vitro digestion/Caco-2 cell model, varied significantly among hybrids in two of the three trials. Location effects were larger than location by genotype interaction effects, additive but not non-additive gene action was significant, and heritability estimates were mostly between 0.55 and 0.65 for Fe bioavailability estimators. Bioavailability of Fe was not associated with Fe concentration in grain or with grain yield. Negative correlation of Fe bioavailability with zinc concentration in grain for one of the three hybrid trials, and positive correlation with provitamin A concentrations in one trial were indicative of inhibitor and enhancer effects on Fe bioavailability, respectively. Although use of the Caco-2 cell model is promising, particularly because it integrates the whole meal, or food matrix effect on Fe bioavailability, the complex nature of the assay and moderate heritability of bioavailability estimators make it most suitable as an intermediate selection tool, following high throughput selection for molecular markers of Fe bioavailability, currently in development by other researchers, and preceding validation and efficacy trials with animal and human models.     

日粮补充β-胡萝卜素对奶牛繁殖性能影响的研究

本试验研究日粮补充β-胡萝卜素对奶牛血液β-胡萝卜素浓度、产后发病率、产后70天内的配种率、受胎率及一次配种受胎率的影响。结果表明:添加300mg/头·天的β-胡萝卜素能显著提高奶牛产前7天、产后10天和产后60天的血液β-胡萝卜素浓度(p<0.05),降低产后胎衣不下和乳腺炎的发病率,提高产后70天内的配种率和配种受胎率,但对一次配种受胎率和配种天数无明显影响。