The sweet cassava breeding programs are focused on the selection of varieties containing carotenoids within the storage roots. The research was conducted with the objective to evaluate the agronomic ...potential and the carotenoid contents within the storage roots of cassava accessions with cream, yellow and pinkish color root pulp aiming their potential direct adoption by producers and/or their use as parents for breeding programs. Thirteen cassava accessions were evaluated in an experiment held at Embrapa Cerrados, for two crop seasons, considering the following characters: height of the first ramification, height of the plant, mass of plant canopy, root productivity, starch percentage within roots, bacterial blast severity, carotenoid contents in roots, root cooking time in minutes and cyanidric acid contents within roots. The results demonstrated existence of significant differences among the accessions for height of the first ramification, height of the plant, mass of plant canopy, root productivity, starch percentage within roots, bacterial blast severity and carotenoid contents within roots. Moreover, it was observed significant variations among crop seasons and significant interaction between the crop seasons and accessions for all the characters evaluated, except for bacterial blast severity and carotenoid contents within roots. No accession presented agronomic performance that would justify commercial cultivation within the Cerrado region of Central Brazil. There were accessions identified with potential for use as parents in plant breeding aiming the increment of P-carotene BGMC 1221, BGMC BGMC 1223 and BGMC 1224 and lycopene BGMC 1222 and BGMC 1229 contents in storage roots. Key words: Manihot esculenta Crantz, cassava, plant breeding, biofortification. Os programas de melhoramento genetico de mandioca de mesa estao focados na selecao de variedades com a presenca de carotenoides nas raizes de reserva. O trabalho foi realizado com o objetivo de avaliar o potencial agronomico e o teor de carotenoides em raizes de reserva de acessos de mandioca com coloracao da polpa das raizes creme, amarela e rosada visando a utilizacao direta por produtores e/ou sua utilizacao como genitores em programas de melhoramento. Treze acessos de mandioca foram avaliados em experimento conduzido na Embrapa Cerrados por duas safras, quanto aos caracteres altura da primeira ramificacao, altura da planta, massa da parte aerea, produtividade de raizes, porcentagem de amido nas raizes, severidade de bacteriose, teor de carotenoides nas raizes, tempo para a coccao em minutos e teor de acido cianidrico nas raizes. Os resultados evidenciaram a existencia de diferencas significativas entre os acessos para os caracteres altura da primeira ramificacao, altura da planta, massa da parte aerea, produtividade de raizes, porcentagem de amido nas raizes, severidade de bacteriose e teor de carotenoides nas raizes. Tambem foram detectadas variacoes significativas entre as safras e interacao significativa entre as safras e acessos para todos os caracteres, com excecao da severidade da bacteriose e do teor de carotenoides nas raizes. Nenhum acesso apresentou desempenho agronomico que justifique o cultivo de forma comercial na regiao do Cerrado do Brasil Central. Foram detectados acessos com potencial para utilizacao no melhoramento, visando ao incremento de beta-caroteno BGMC 1221, BGMC BGMC 1223 e BGMC 1224 e de licopeno BGMC 1222 e BGMC 1229 em raizes de reserva. Palavras-chave: Manihot esculenta Crantz, aipim, melhoramento genetico, biofortificacao.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The sweet cassava breeding programs are focused on the selection of varieties containing carotenoids within the storage roots. The research was conducted with the objective to evaluate the agronomic ...potential and the carotenoid contents within the storage roots of cassava accessions with cream, yellow and pinkish color root pulp aiming their potential direct adoption by producers and/or their use as parents for breeding programs. Thirteen cassava accessions were evaluated in an experiment held at Embrapa Cerrados, for two crop seasons, considering the following characters: height of the first ramification, height of the plant, mass of plant canopy, root productivity, starch percentage within roots, bacterial blast severity, carotenoid contents in roots, root cooking time in minutes and cyanidric acid contents within roots. The results demonstrated existence of significant differences among the accessions for height of the first ramification, height of the plant, mass of plant canopy, root productivity, starch percentage within roots, bacterial blast severity and carotenoid contents within roots. Moreover, it was observed significant variations among crop seasons and significant interaction between the crop seasons and accessions for all the characters evaluated, except for bacterial blast severity and carotenoid contents within roots. No accession presented agronomic performance that would justify commercial cultivation within the Cerrado region of Central Brazil. There were accessions identified with potential for use as parents in plant breeding aiming the increment of P-carotene BGMC 1221, BGMC BGMC 1223 and BGMC 1224 and lycopene BGMC 1222 and BGMC 1229 contents in storage roots.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•Umbrella review of 20 outcomes in 17 systematic reviews and meta-analyses.•Tomato intake benefited mortality, prostate cancer, and gastric cancer.•Lycopene benefited mortality, prostate cancer, CVD, ...and metabolic syndrome.•Caution was warranted for potential allergy and pollution.•But the quality of the evidence was not high.
Lycopene is a potent lipophilic antioxidant in tomato. We aim to clarify the evidence for associations between tomato and lycopene and multiple health outcomes. Umbrella review of meta-analyses and systematic reviews was performed in humans. A total of 174 articles were searched, 17 articles with 20 health outcomes were identified by eligibility criteria. Tomato intake was inversely associated with all-cause mortality, coronary heart disease mortality, cerebrovascular disease mortality, prostate cancer, and gastric cancer. Dietary lycopene intake or serum lycopene was inversely associated with all-cause mortality, prostate cancer, stroke, cardiovascular disease, metabolic syndrome, and male infertility. Caution was warranted for potential allergy and pollution. The quality of the vast majority of evidence by GRADE was low or very low with the remaining six as moderate. The intake of tomato or lycopene was generally safe and beneficial for multiple health outcomes in humans. But the quality of the evidence was not high.
Substrate inhibition of enzymes can be a major obstacle to the production of valuable chemicals in engineered microorganisms. Here, we show substrate inhibition of lycopene cyclase as the main ...limitation in carotenoid biosynthesis in Yarrowia lipolytica. To overcome this bottleneck, we exploit two independent approaches. Structure-guided protein engineering yields a variant, Y27R, characterized by complete loss of substrate inhibition without reduction of enzymatic activity. Alternatively, establishing a geranylgeranyl pyrophosphate synthase-mediated flux flow restrictor also prevents the onset of substrate inhibition by diverting metabolic flux away from the inhibitory metabolite while maintaining sufficient flux towards product formation. Both approaches result in high levels of near-exclusive β-carotene production. Ultimately, we construct strains capable of producing 39.5 g/L β-carotene at a productivity of 0.165 g/L/h in bioreactor fermentations (a 1441-fold improvement over the initial strain). Our findings provide effective approaches for removing substrate inhibition in engineering pathways for efficient synthesis of natural products.
Lutein, as a carotenoid with strong antioxidant capacity and an important component of macular pigment in the retina, has wide applications in pharmaceutical, food, feed, and cosmetics industries. ...Besides extraction from plant and algae, microbial fermentation using engineered cell factories to produce lutein has emerged as a promising route. However, intra‐pathway competition between the lycopene cyclases and the conflict between cell growth and production are two major challenges. In our previous study, de novo synthesis of lutein had been achieved in Saccharomyces cerevisiae by dividing the pathway into two stages (δ‐carotene formation and conversion) using temperature as the input signal to realize sequential cyclation of lycopene. However, lutein production was limited to microgram level, which is still too low to meet industrial demand. In this study, a dual‐signal hierarchical dynamic regulation system was developed and applied to divide lutein biosynthesis into three stages in response to glucose concentration and culture temperature. By placing the genes involved in δ‐carotene formation under the glucose‐responsive ADH2 promoter and genes involved in the conversion of δ‐carotene to lutein under temperature‐responsive GAL promoters, the growth‐production conflict and intra‐pathway competition were simultaneously resolved. Meanwhile, the rate‐limiting lycopene ε‐cyclation and carotene hydroxylation reactions were improved by screening for lycopene ε‐cyclase with higher activity and fine tuning of the P450 enzymes and their redox partners. Finally, a lutein titer of 19.92 mg/L (4.53 mg/g DCW) was obtained in shake‐flask cultures using the engineered yeast strain YLutein‐3S‐6, which is the highest lutein titer ever reported in heterologous production systems.
•Guava juice was processed by high power ultrasound.•This process disrupted guava cells altering the juice properties.•The juice physical stability was improved, avoiding pulp ...sedimentation.•Ultrasound decreases the amount of lycopene in guava juice.•Ultrasound increased the in vitro accessibility of lycopene in guava juice.
The present work evaluated the effect of high-power ultrasonication on the structure and properties of guava juice. The microstructure, concentration of lycopene, in vitro accessibility of lycopene and physical properties (pulp sedimentation, turbidity and colour) were evaluated. The results of this study demonstrate that the ultrasonication disrupts the guava cells, releasing their content and altering the juice properties. Although this processing decreases the total amount of lycopene in guava juice, the release of lycopene from the cells increased its in vitro accessibility. Furthermore, the size reduction of the dispersed pulp particles improved the physical stability of the juice, avoiding pulp sedimentation without significant colour changes during storage. In conclusion, it is suggested that ultrasonication is an interesting alternative to improve the physical and nutritional properties of fruit juices.
The influence of physicochemical properties of carrier oils on nanoemulsion stability and the bioaccessibility of lycopene were studied. Lycopene-loaded nanoemulsions were prepared by using sesame ...oil, linseed oil or walnut oil as the oil phase and lactoferrin as the emulsifier. The stability was investigated by particle size, zeta potential, pH sensitivity, thermal stability and lycopene retention. Results showed that the stability was positively correlated with oil density but negatively related to oil viscosity and unsaturation degree; the lycopene nanoemulsion prepared by sesame oil exhibited greater stability and a slower degradation rate of lycopene compared to the other nanoemulsions. In addition, the lycopene retention in sesame oil-nanoemulsions was significantly higher during the first three weeks of storage. The bioaccessibility of lycopene, as measured by a simulated gastrointestinal model, was greatly improved in the nanoemulsion system. The lycopene bioaccessibility was around 25% in sesame oil- and linseed oil-nanoemulsions, and 18% in walnut oil-nanoemulsions, showing a similar trend with their stability. This information may facilitate the design of more efficacious lycopene-fortified delivery systems.
•The stability and bioavailability of the prepared nanoemulsions were studied by using three different vegetable oils.•Provides a reference for the preparation of a stable and efficient nanoemulsion system.•Enables lycopene to enhance its stability and bioaccessibility through a stable and efficient nanoemulsion delivery system.
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Recent mechanistic and epidemiological studies have provided insights into health benefits of dietary lycopene to decrease the risk and complications associated with several chronic ...diseases such as cardiovascular diseases (CVD), obesity, type 2 diabetes, cancer, and neurodegenerative disorders. These chronic diseases are primarily associated with oxidative stress-induced systemic and low-grade chronic inflammation. Owing to its potent antioxidant properties, lycopene can potentially alleviate enhanced levels of proinflammatory mediators (e.g., proinflammatory cytokines IL-8, -6, and -1, and oxidized phospholipids) and prevent NF-κB activation by modulating oxidative stress. Moreover, lycopene serves as a precursor for various oxidative cleavage products and metabolites including Apo-8’-, apo-10’-, and apo-12’-lycopenals that can interact with multiple transcription factors (e.g., Nrf2, RARs, RXRs, and PPARs) to overexpress antioxidant and cytoprotective Phase II enzymes and other growth-stimulating proteins (e.g., brain-derived neurotrophic factor (BDNF) for enhanced neuroprotection. These events altogether can protect the body from chronic inflammatory disorders. In the present review, the latest mechanistic development from cell and animal models and results of case-control, cohort, and randomized trials are discussed to support the protective part of lycopene in cancer, CVD, and neurodegenerative disorders. This review focuses on cellular and molecular events involved in protective effects of lycopene. Although molecular and cellular mechanisms involved in health-promoting activities of lycopene have been reported, no detailed mechanistic studies have been published. Hence, future studies should be conducted to elucidate the mechanistic role(s) of lycopene-derived oxidation products in modulating cellular signaling.
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