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1.
Molecules ; 28(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36677741

RESUMO

Arabica-coffee and Theobroma-cocoa agroindustrial wastes were treated with NaOH and characterized to efficiently remove Pb(II) from the aqueous media. The maximum Pb(II) adsorption capacities, qmax, of Arabica-coffee (WCAM) and Theobroma-cocoa (WCTM) biosorbents (qmax = 303.0 and 223.1 mg·g-1, respectively) were almost twice that of the corresponding untreated wastes and were higher than those of other similar agro-industrial biosorbents reported in the literature. Structural, chemical, and morphological characterization were performed by FT-IR, SEM/EDX, and point of zero charge (pHPZC) measurements. Both the WCAM and WCTM biosorbents showed typical uneven and rough cracked surfaces including the OH, C=O, COH, and C-O-C functional adsorbing groups. The optimal Pb(II) adsorption, reaching a high removal efficiency %R (>90%), occurred at a pH between 4 and 5 with a biosorbent dose of 2 g·L-1. The experimental data for Pb(II) adsorption on WACM and WCTM were well fitted with the Langmuir-isotherm and pseudo-second order kinetic models. These indicated that Pb(II) adsorption is a chemisorption process with the presence of a monolayer mechanism. In addition, the deduced thermodynamic parameters showed the endothermic (ΔH0 > 0), feasible, and spontaneous (ΔG0 < 0) nature of the adsorption processes studied.


Assuntos
Cacau , Coffea , Poluentes Químicos da Água , Café , Chumbo , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Termodinâmica , Água/química , Cinética , Adsorção
2.
Food Res Int ; 163: 112253, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36596163

RESUMO

Physicochemical transformation of coffee during roasting depends on the applied time-temperature profile (i.e., rate of heat transfer), with heat transfer phenomena governed by particle dynamics. Positron Emission Particle Tracking (PEPT), a non-invasive imaging technique, was used here to characterise the granular flow of coffee in a real, pilot-scale rotating drum roaster. The experimental study established the impact of drum speed, batch size and bean density (i.e., roast degree) on the system's particle dynamics. Particle motion data revealed two distinct regions: (i) a disperse (low occupancy, high velocity) region of in-flight particles and (ii) a dense (high occupancy, low velocity) bean bed. Implications of these results for heat transfer suggest that controlling drum speed for different density coffees will provide roaster operators with a tool to modulate conductive heat transfer from the heated drum to the bean bed. These comprehensive data thus inform roasting best practices and support the development of physics-driven models coupling heat and mass transfer to particle dynamics.


Assuntos
Coffea , Elétrons , Temperatura Alta , Sementes
3.
Genes (Basel) ; 14(1)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36672930

RESUMO

In this study, marker-assisted recurrent selection was evaluated for pyramiding resistance gene alleles against coffee leaf rust (CLR) and coffee berry diseases (CBD) in Coffea arabica. A total of 144 genotypes corresponding to 12 hybrid populations from crosses between eight parent plants with desired morphological and agronomic traits were evaluated. Molecular data were used for cross-certification, diversity study and resistance allele marker-assisted selection (MAS) against the causal agent of coffee leaf rust (Hemileia vastatrix) and coffee berry disease (Colletotrichum kahawae). In addition, nine morphological and agronomic traits were evaluated to determine the components of variance, select superior hybrids, and estimate genetic gain. From the genotypes evaluated, 134 were confirmed as hybrids. The genetic diversity between and within populations was 75.5% and 24.5%, respectively, and the cluster analysis revealed three primary groups. Pyramiding of CLR and CBD resistance genes was conducted in 11 genotypes using MAS. A selection intensity of 30% resulted in a gain of over 50% compared to the original population. Selected hybrids with increased gain also showed greater genetic divergence in addition to the pyramided resistance alleles. The strategies used were, therefore, efficient to select superior coffee hybrids for recurrent selection programs and could be used as a source of resistance in various crosses.


Assuntos
Coffea , Resistência à Doença , Resistência à Doença/genética , Coffea/genética , Alelos , Doenças das Plantas/genética
4.
Food Funct ; 14(1): 262-276, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36484426

RESUMO

The scientific interest in the medicinal properties of Kombucha beverages, a carbonated drink with live microorganisms, has increased recently. Hence, the aim of this study was to determine the chemical profile and to examine the antioxidant, antidiabetic and antineurodegenerative potential of unfermented and also Kombucha fermented Camellia sinensis (green tea), Coffea arabica (coffee), and Ganoderma lucidum (Reishi) extracts. The extracts were prepared as follows: the first (unfermented) set contained 1 L of water, 50 g of sucrose and 20 g of dried and ground green tea, coffee, or Reishi basidiocarp, while the second (fermented) set contained all of the aforementioned ingredients individually inoculated with Kombucha and fermented for 21 days. The chemical analysis was conducted using liquid chromatography-mass spectrometry (LC-MS). The antioxidant activity was assessed by DPPH, total reducing power (TRP), and ß-carotene bleaching assays. The inhibition of α-amylase and α-glucosidase activity was used to estimate the antidiabetic potential, while the level of inhibition of acetylcholinesterase (AChE) and tyrosinase (TYR) was used to evaluate the antineurodegenerative activity. The results suggested that the fermented extracts of green tea, coffee, and Reishi exert significant antioxidant effects, although they were lower compared to the unfermented extracts. The unfermented green tea extract exhibited the highest DPPH-scavenging activity (87.46%) and the highest preservation of ß-carotene (92.41%), while the fermented coffee extract showed the highest TRP (120.14 mg AAE per g) at 10 mg mL-1. Although the extracts did not inhibit the activity of α-amylase, they were quite effective at inhibiting α-glucosidase, especially the unfermented Reishi extract, inhibiting 95.16% (at a concentration of 10 mg mL-1) of α-glucosidase activity, which was slightly higher than the positive control at the same concentration. The most effective AChE inhibitor was unfermented green tea extract (68.51%), while the fermented coffee extract inhibited 34.66% of TYR activity at 10 mg mL-1. Altogether, these results are in accordance with the differences found in the extracts' chemical composition. Finally, this is the first report that highlights the differences in the chemical profile between the unfermented and Kombucha fermented green tea, coffee and Reishi extracts, while it also reveals, for the first time, the antineurodegenerative potential of Kombucha fermented Reishi extract. The examined extracts represent potent functional foods, while their more detailed mechanisms of action are expected to be revealed in future research.


Assuntos
Camellia sinensis , Coffea , Reishi , Antioxidantes/farmacologia , Antioxidantes/análise , Camellia sinensis/química , Hipoglicemiantes/farmacologia , Hipoglicemiantes/análise , alfa-Glucosidases , Acetilcolinesterase , beta Caroteno/análise , Cromatografia Gasosa-Espectrometria de Massas , Chá/química , alfa-Amilases , Extratos Vegetais/farmacologia , Extratos Vegetais/química
5.
Plant Physiol Biochem ; 194: 627-637, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36535102

RESUMO

Species of the genus Coffea accumulate diterpenes of the ent-kaurane family in the endosperm of their seeds, of which cafestol and kahweol are the most abundant. The diterpenes are mainly stored in esterified form with fatty acids, mostly palmitate. In contrast to the numerous studies on their effects on human health and therapeutic applications, nothing was previously known about their biological and ecological role in planta. The antifungal and anti-insect activities of cafestol and cafestol palmitate were thus investigated in this study. Cafestol significantly affected the mycelial growth of five of the six phytopathogenic fungi tested. It also greatly reduced the percentage of pupation of larvae and the pupae and adult masses of one of the two fruit flies tested. By contrast, cafestol palmitate had no significant effect against any of the fungi and insects studied. Using confocal imaging and oil body isolation and analysis, we showed that diterpenes are localized in endosperm oil bodies, suggesting that esterification with fatty acids enables the accumulation of large amounts of diterpenes in a non-toxic form. Diterpene measurements in all organs of seedlings recovered from whole seed germination or embryos isolated from the endosperm showed that diterpenes are transferred from the endosperm to the cotyledons during seedling growth and then distributed to all organs, including the hypocotyl and the root. Collectively, our findings show that coffee diterpenes are broad-spectrum defence compounds that protect not only the seed on the mother plant and in the soil, but also the seedling after germination.


Assuntos
Coffea , Diterpenos , Humanos , Café , Plântula/química , Antifúngicos/farmacologia , Endosperma/química , Germinação , Diterpenos/farmacologia , Sementes/química , Ácidos Graxos
6.
J Food Sci ; 88(1): 214-227, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36533940

RESUMO

Drying is a key step that affects the chemical composition and quality of tea. In the present study, we reported the impacts of drying temperature and time on drying and color change kinetics, phytochemical composition, antioxidant activity, and surface microstructure of coffee leaves during hot-air drying. The results showed that drying temperature was positively (p < 0.05) correlated with the drying rate (DR), color index a* and total color change ΔE, and total soluble sugar (TSS), while negatively correlated with color indexes b* and L*, soluble protein content, and the DPPH scavenging capacity. Drying time has similar impacts on the color indexes and soluble protein as drying temperature. The content of total free amino acid and TSS increased by 62.5% and 47.4%, respectively, when coffee leaves were dried at 160°C for 24 min, under which the total phenolic content and DPPH and ABTS scavenging capacities reached the maximum of 108.04 mg GAE/g, 515.07 µmol Trolox/g, and 606.70 µmol Trolox/g, respectively. Drying significantly decreased the contents of chlorogenic acids and mangiferin and antioxidant activity, while high-temperature short-time drying helped retain phenolic compounds in coffee leaves. The DR fitted Page kinetic model. The color changes fitted the first-order kinetic models and the activation energies ranged from 16.00 to 31.06 kJ·mol-1 . Prolonged drying time caused serious wrinkles on the surface of coffee leaves and the stomata closed. PRACTICAL APPLICATION: Drying decreased soluble protein while increasing free amino acid and soluble sugar. High-temperature short-time drying helps retain phenolics in the coffee leaves. The color change of coffee leaves during drying follows first-order kinetic. Prolonged drying time resulted in loosened texture of coffee leaves. Our study suggested that drying coffee leaves at 160°C for 24 min results in the coffee leaf tea being of better quality.


Assuntos
Antioxidantes , Coffea , Antioxidantes/química , Dessecação/métodos , Fenóis/análise , Chá
7.
Food Chem ; 409: 135317, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-36586269

RESUMO

The advancement in the use of spectroscopic techniques to investigate coffee samples is of high interest especially considering the widespread problems with coffee adulteration and counterfeiting. In this work, the use of solid-state nuclear magnetic resonance (NMR) is investigated as a means to probe the various chemically-distinct phases existent in roasted coffee samples and to detect the occurrence of counterfeiting or adulterations in coffee blends. Routine solid-state 1H and 13C NMR spectra allowed the distinction between different coffee types (Arabica/Robusta) and the evaluation of the presence of these components in coffee blends. On the other hand, the use of more specialized solid-state NMR experiments revealed the existence of phases with different molecular mobilities (e.g., associated with lipids or carbohydrates). The results illustrate the usefulness of solid-state NMR spectroscopy to examine molecular mobilities and interactions and to aid in the quality control of coffee-related products.


Assuntos
Coffea , Café , Café/química , Coffea/química , Sementes/química , Espectroscopia de Ressonância Magnética/métodos , Imageamento por Ressonância Magnética
10.
J Environ Sci Health B ; 57(12): 989-998, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36573489

RESUMO

Caffeine content is a crucial attribute of coffee. Its concentration and thus maximum cups of Coffea arabica from Africa, Asia, Central America, and South America from different altitudes of growing areas, altitude, and process using different post-harvest processing (dry, wet, and pulped natural). Our results suggest that geographical origin might affect the alkaloid concentration in C. arabica. The caffeine concentration pattern in green samples was as follows: Central America > South America > Asia > Africa. Altitude affected the concentrations, lowlands > midlands > highlands, however, not significantly. Given caffeine is thermostable, the medium roasting process did not affect the concentration of caffeine directly, but a small increase was observed. Scientific opinion on the safety of habitual caffeine consumption of up to 400 mg per day does not raise safety concerns for non-pregnant adults. A cup (7 g coffee in 120 mL of water) was used for recalculation. Results suggest that mostly highlands and midlands coffee from Africa reached levels of caffeine that might be consumed in more than 5.5 cups a day.


Assuntos
Cafeína , Coffea , Adulto , Humanos , Altitude , Cafeína/efeitos adversos , Cafeína/análise , Coffea/química , Café , Recomendações Nutricionais
11.
Molecules ; 27(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36500526

RESUMO

Coffee bean harvesting incurs various by-products known for their long traditional use. However, they often still end up being a waste instead of being used to their full potential. On the European market, coffee cherry (cascara) products are not yet common, and a novel food approval for beverages made from coffee cherry pulp was issued only recently. In this article, exposure and risk assessment of various products such as juice, jam, jelly, puree, and flour made from coffee cherry pulp and husk are reviewed. Since caffeine in particular, as a bioactive ingredient, is considered a limiting factor, safe intake will be derived for different age groups, showing that even adolescents could consume limited quantities without adverse health effects. Moreover, the composition can be influenced by harvesting methods and processing steps. Most interestingly, dried and powdered coffee cherry can substitute the flour in bakery products by up to 15% without losing baking properties and sensory qualities. In particular, this use as a partial flour substitute is a possible approach to counteract rising grain prices, transport costs, and disrupted supply chains, which are caused by the Russia-Ukraine war and changing climatic conditions. Thus, the supply of affordable staple foods could be partially ensured for the inhabitants of countries that depend on imported wheat and cultivate coffee locally by harvesting both beans and by-products.


Assuntos
Coffea , Frutas , Sementes , Cafeína , Medição de Risco
12.
Molecules ; 27(23)2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36500625

RESUMO

The aim of this study was to detect and identify the volatile compounds in coffee that was obtained in defect roast processes versus standard roasting and to determine the type and strength of the correlations between the roast defects and the volatile compound profile in roasted coffee beans. In order to achieve this goal, the process of coffee bean roasting was set to produce an underdeveloped coffee defect, an overdeveloped coffee defect, and defectless coffee. The "Typica" variety of Arabica coffee beans was used in this study. The study material originated from a plantation that is located at an altitude of 1400-2000 m a.s.l. in Huehuetenango Department, Guatemala. The analyses were carried out with the use of gas chromatography/mass spectrometry (GC-MS) and an electronic nose. This study revealed a correlation between the identified groups of volatile compounds and the following coffee roasting parameters: the time to the first crack, the drying time, and the mean temperatures of the coffee beans and the heating air. The electronic nose helped to identify the roast defects.


Assuntos
Coffea , Nariz Eletrônico , Cromatografia Gasosa-Espectrometria de Massas , Manipulação de Alimentos/métodos , Dessecação , Temperatura , Temperatura Alta , Coffea/química
13.
Molecules ; 27(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36364160

RESUMO

Kahweol and cafestol are two diterpenes extracted from Coffea arabica beans that have distinct biological activities. Recent research describes their potential activities, which include anti-inflammatory, anti-diabetic, and anti-cancer properties, among others. The two diterpenes have been shown to have anticancer effects in various in vitro and in vivo cancer models. This review aims to shed light on the recent developments regarding the potential effects of kahweol and cafestol on various cancers. A systematic literature search through Google Scholar and PubMed was performed between February and May 2022 to collect updates about the potential effects of cafestol and kahweol on different cancers in in vitro and in vivo models. The search terms "Kahweol and Cancer" and "Cafestol and Cancer" were used in this literature review as keywords; the findings demonstrated that kahweol and cafestol exhibit diverse effects on different cancers in in vitro and in vivo models, showing pro-apoptotic, cytotoxic, anti-proliferative, and anti-migratory properties. In conclusion, the diterpenes kahweol and cafestol display significant anticancer effects, while remarkably unaffecting normal cells. Our results show that both kahweol and cafestol exert their actions on various cancers via inducing apoptosis and inhibiting cell growth. Additionally, kahweol acts by inhibiting cell migration.


Assuntos
Coffea , Diterpenos , Neoplasias , Humanos , Diterpenos/farmacologia , Diterpenos/análise , Apoptose , Neoplasias/tratamento farmacológico , Café
14.
Anal Methods ; 14(46): 4756-4766, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36398971

RESUMO

Coffee is the most consumed beverage and the second most valuable traded commodity in the world. In this current study, a pocket-sized spectrometer and multivariate analysis were used for rapid authentication of coffee varieties (Arabica and Robusta) in three states to check mislabelling (food fraud). Two main coffee varieties were collected from different locations in Africa. The samples were scanned in the 740-1070 nm wavelength and the spectral data were pre-treated with several methods: mean centering (MC), multiplicative scatter correction (MSC), first derivative (FD), second derivative (SD) and standard normal variate (SNV) independently while partial least squares discriminate analysis (PLS-DA), K-nearest neighbour (KNN) and support vector machine (SVM) were used to comparatively build the prediction models for coffee beans (raw, roasted and powdered). The performances of the models were evaluated by using accuracy and efficiency. Among the classification methods developed, the best results were obtained for the following: raw coffee bean SD-SVM had an accuracy of 0.92 and efficiency of 0.82. For roasted coffee beans, SD-KNN had an accuracy of 0.92 and efficiency of 0.87, while for roasted powdered coffee, FD-KNN showed an accuracy of 0.97 and efficiency of 0.97. These finding reveals that for a more accurate differentiation of coffee beans, the roasted powder offers the best results. The obtained results showed that a pocket-sized spectrometer coupled with chemometrics could be employed to provide accurate and rapid authentication of different categories of coffee bean varieties.


Assuntos
Coffea , Alimentos , Bebidas , Pós , Análise Multivariada , Emolientes
15.
Molecules ; 27(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36431856

RESUMO

Coffee bean bagasse is one of the main by-products generated by industrial coffee production. This by-product is rich in bioactive compounds such as caffeine, caffeic and chlorogenic acid, and other phenols. The aims of this work are to optimize the extraction conditions of phenolic compounds present in coffee bean bagasse and incorporate them into stout-style craft beers, as well as to determine their effect on the phenol content and antioxidant capacity. The optimal conditions for extraction were 30% ethanol, 30 °C temperature, 17.5 mL of solvent per gram of dry sample, and 30 min of sonication time. These conditions presented a total phenol content of 115.42 ± 1.04 mg GAE/g dry weight (DW), in addition to an antioxidant capacity of 39.64 ± 2.65 µMol TE/g DW in DPPH• and 55.51 ± 6.66 µMol TE/g DW for FRAP. Caffeine, caffeic and chlorogenic acids, and other minor compounds were quantified using HPLC-DAD. The coffee bean bagasse extracts were added to the stout craft beer and increased the concentration of phenolic compounds and antioxidant capacity of the beer. This work is the first report of the use of this by-product added to beers.


Assuntos
Antioxidantes , Coffea , Antioxidantes/análise , Cerveja , Cafeína , Fenol , Fenóis/análise , Extratos Vegetais/análise
16.
Molecules ; 27(22)2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36431907

RESUMO

Coffee cherry is a rich source of caffeine and chlorogenic acids. In this study we investigate the structural analysis of caffeine-enriched whole coffee cherry extracts, CEWCCE by using 1H and 13C NMR spectroscopy. The changes in 1H chemical shift data in NMR spectra of CEWCCE compared to pure caffeine indicated the formation of complexes between caffeine and chlorogenic acids in aqueous solution. The effect of complexation on the peak position of caffeoylquinic acid and caffeine resonance with increasing addition of caffeine was investigated. 2D NOESY experiments show the presence of cross-peaks that are due to the proximity of chlorogenic acid and caffeine molecules in stable complexes in protic solvents. The quantification data of caffeine by 1H qNMR was found to be in close agreement with the data obtained by HPLC analysis.


Assuntos
Coffea , Prunus avium , Coffea/química , Café/química , Ácido Clorogênico/química , Cafeína/análise , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química
17.
Sensors (Basel) ; 22(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36433248

RESUMO

The roasting process is one of the critical points to obtain a product of the highest quality with certain sensorial properties including the aroma of coffee. Samples of coffee beans were roasted at different thermal treatment intensities with the aim of obtaining aromatic compounds detected with an electronic device. Sensory analysis, volatile compound profiling, and electronic nose analysis were carried out. Through principal component analysis (95.8% of the total variance of the data was explained by PC1 and PC2) and partial least squares discriminant analysis (the sum of the diagonal elements gave a hit rate of 94%), it could be demonstrated that the E-nose is able to discriminate roasted coffee beans subjected to different thermal treatments. Aromatic profiling was carried out by a testing panel and volatile compounds (VOCs) for the discrimination of roasted coffee samples. Alcohols, aromatics, esters, ketones and furanone were found in higher proportions in samples at the lowest thermal treatment. The VOCs with positive attributes were 1-(4-nitrophenyl)-3-phenylamino-propenone, carboxylic acids, 2-methoxy-4-vinylphenol, and 2-phenylethyl alcohol, while the compounds with negative ones were 2-methyl-furan, 2,5-dimethyl-pyridine, 2-methyl-butanal, and 2-furfurylthiol. The PLS model allows for the quantification of the positive and negative aromas (RCV2 = 0.92) of roasted coffee by using the E-nose. Therefore, the E-nose, that is, an inexpensive and nondestructive instrument, could be a chemometric tool able to discriminate between different qualities of coffee during processing.


Assuntos
Coffea , Olfato , Odorantes/análise , Manipulação de Alimentos , Alimentos
18.
Artigo em Inglês | MEDLINE | ID: mdl-36293801

RESUMO

This study aimed to investigate the effect of spray drying (SD) and freeze-drying (FD) on the microencapsulation of green coffee extracts by using polydextrose (PD) and inulin (IN) as encapsulating agents and their physicochemical, bioactive compounds' stability, phenolic compounds' bioaccessibility after digestion, and sensory effects in unfermented dairy beverages. The extract encapsulated with IN by FD had lower moisture content, water activity, and hygroscopicity, while particles encapsulated by SD exhibited a spherical shape and the structure of the FD products was irregular. No difference was observed in phenolic compounds' bioaccessibility. Dairy beverages with added encapsulated extracts had higher total phenolic content and antioxidant activity. Microencapsulation allowed a controlled release of the bioactive compounds with an increase in the content of caffeine, chlorogenic acid, and trigonelline during storage. The dairy beverage with added extract encapsulated with IN by FD had the highest scores of acceptability regarding the overall impression and purchase intent.


Assuntos
Coffea , Extratos Vegetais , Antioxidantes/química , Bebidas , Cafeína/análise , Ácido Clorogênico/análise , Preparações de Ação Retardada , Inulina/química , Fenóis/química , Extratos Vegetais/química , Laticínios
19.
Molecules ; 27(20)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36296431

RESUMO

Roasted coffee silver skin is a coffee by-product, the uses of which are currently limited, e.g., as fertilizer, for energy production, or animal feed. Due to a low content of fat and carbohydrates combined with a high content of fiber, polyphenols and proteins, roasted silver skin is a valuable possible food ingredient. Potential applications include partial flour replacement in bakery products, as antioxidant and providing protein or fiber sources in sports or functional foods. As no relevant consumption of isolated silver skin occurred before 1997 in the European Union (EU), it was classified as a novel food in need of premarketing approval. Novel food applications must meet legal requirements for compositional and toxicological information. This review presents information on silver skin composition and toxicological studies. Several in vitro studies and subchronic in vivo studies are available with negative results, not suggesting a need for further studies on carcinogenic effects, reproduction, or chronic toxicity. All available studies so far concluded that no toxic effects of silver skin were found or are to be expected. For a novel food application in the EU, further in vitro studies on mutagenic potential may be needed to close a formal data gap.


Assuntos
Coffea , Ingredientes de Alimentos , Animais , Antioxidantes , Carboidratos , Coffea/toxicidade , Ingredientes de Alimentos/toxicidade
20.
Sci Rep ; 12(1): 17270, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36241651

RESUMO

Coffea canephora (2n = 2x = 22 chromosomes) is a species with extensive genetic diversity and desirable agronomic traits for coffee breeding programs. However, obtaining a new coffee cultivar through conventional breeding techniques may require more than 30 years of crossing cycles and selection, which hampers the effort of keeping up with market demands and rapidly proposing more resilient to climate change varieties. Although, the application of modern biotechnology tools such as precision genetic engineering technologies may enable a faster cultivar development process. Therefore, we aimed to validate the CRISPR/Cas9 system to generate mutations on a selected genotype of C. canephora, the clone 14. Embryogenic calli and a multiplex binary vector containing two sgRNAs targeting different exons of the CcPDS gene were used. The sgRNAs were under the C. canephora U6 promoter regulation. The target gene encodes phytoene desaturase, an enzyme essential for photosynthesis involved in ß-carotene biosynthesis. Somatic seedlings and embryos with albino, variegated and green phenotypes regenerated after Agrobacterium tumefaciens-mediated genetic transformation were analyzed by verifying the insertion of the Cas9 gene and later by sequencing the sgRNAs target regions in the genome of Robusta modified seedlings. Among them, 77% had the expected mutations, and of which, 50% of them had at least one target with a homozygous mutation. The genotype, temperature of co-cultivation with the bacteria, and light intensity used for subsequent embryo regeneration appeared to strongly influence the successful regeneration of plants with a mutated CcPDS gene in the Coffea genus.


Assuntos
Coffea , Sistemas CRISPR-Cas , Coffea/genética , Café , Edição de Genes , Oxirredutases , Melhoramento Vegetal , beta Caroteno
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