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1.
J Sci Food Agric ; 103(10): 4792-4802, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36897036

RESUMO

BACKGROUND: (+)-Nootkatone is a highly valuable sesquiterpene compound that can be used as an aromatic in the food industry because of its grapefruit flavor and low sensory threshold. The unconventional yeast Yarrowia lipolytica has many unique physical and chemical properties, metabolic characteristics, and genetic structure, which has aroused the interest of researchers. Previous research showed that Y. lipolytica possesses the ability to transform the sesquiterpene (+)-valencene to (+)-nootkatone. The aim of this study was to isolate, purify, and identify the enzyme involved in the (+)-valencene bioconversion to (+)-nootkatone by Y. lipolytica. RESULTS: In this study, ultrasonic-assisted extraction, ammonium sulfate precipitation, anion-exchange chromatography, and gel-filtration chromatography were used to separate and purify the enzyme involved in the (+)-valencene bioconversion by Y. lipolytica. The protein was identified as aldehyde dehydrogenase (ALDH) (gene0658) using sodium dodecyl sulfate polyacrylamide gel electrophoresis and liquid chromatography-tandem mass spectrometry analysis. The ALDH had the highest activity when the pH value was 6.0 and the temperature was 30 °C. The activity of ALDH was significantly stimulated by ferrous ions and inhibited by barium, calcium, and magnesium ions. CONCLUSION: This is the first time that ALDH was found to participate in (+)-valencene biotransformation by Y. lipolytica. It may be involved in regulating the microbial transformation of (+)-valencene to (+)-nootkatone through redox characteristics. This study provides a theoretical basis and reference for the biological synthesis of citrus flavor (+)-nootkatone. © 2023 Society of Chemical Industry.


Assuntos
Citrus , Sesquiterpenos , Yarrowia , Yarrowia/genética , Yarrowia/metabolismo , Sesquiterpenos/análise , Espectrometria de Massas , Biotransformação , Citrus/química
2.
J Sci Food Agric ; 103(1): 380-388, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35894931

RESUMO

BACKGROUND: Studies have found that the addition of plant essential oils to feed had a positive effect on intestinal microflora and immunity in mice. However, the effect of different ways of ingestion of orange essential oil on mice has seldom been reported. In the present study, we investigated the effects of ingestion of orange essential oil by gavage, sniffing and feeding on intestinal microflora and immunity in mice. RESULTS: The results obtained showed that a low concentration of essential oil feeding significantly increased the spleen index of mice (P < 0.05). The effect of different ways of ingestion on the thymus index, immunoglobulin G and immunoglobulin M of mice was not significant (P > 0.05). High and medium concentrations of essential oil feeding increased the level of interleukin-2 in mice (P < 0.05). H+ K+ -ATPase activity was significantly increased in mice fed with gavage and different concentrations of essential oil feed compared to the control group (P < 0.05). The analysis of the results of the microflora in the cecum and colon of mice indicated that the medium concentration of essential oil feeding group and the sniffing group significantly changed the structure of the flora and increased the diversity of the intestinal microflora. All three essential oil ingestion methods increased the abundance of Bacteroidetes and Lactobacillus in the intestine of mice. CONCLUSION: Compared with gavage and feeding, sniffing had a significant effect on immunoglobulins in mice. All the three ingestion methods could affect the intestinal microflora of mice and increase the abundance of Lactobacillus. © 2022 Society of Chemical Industry.


Assuntos
Microbioma Gastrointestinal , Óleos Voláteis , Óleos Voláteis/farmacologia , Lactobacillus , Intestinos , Ceco
3.
J Sci Food Agric ; 102(8): 3297-3307, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34800295

RESUMO

BACKGROUND: Natural dihydrocarvone has been widely used in the food, cosmetics, agrochemicals and pharmaceuticals industries because of its sensory properties and physiological effects. In our previous study, Klebsiella sp. O852 was shown to be capable of converting limonene to trans-dihydrocarvone with high catalytic efficiency. Thus, it was essential to identify and characterize the functional genes involved in limonene biotransformation using genome sequencing and heterologous expression. RESULTS: The 5.49-Mb draft genome sequence of Klebsiella sp. O852 contained 5218 protein-encoding genes. Seven candidate genes participating in the biotransformation of limonene to trans-dihydrocarvone were identified by genome analysis. Heterologous expression of these genes in Escherichia coli BL21(DE3) indicated that 0852_GM005124 and 0852_GM003417 could hydroxylate limonene in the six position to yield carveol, carvone and trans-dihydrocarvone. 0852_GM002332 and 0852_GM001602 could catalyze the oxidation of carveol to carvone and trans-dihydrocarvone. 0852_GM000709, 0852_GM001600 and 0852_GM000954 had high carvone reductase activity toward the hydrogenation of carvone to trans-dihydrocarvone. CONCLUSION: The results obtained in the present study suggest that the seven genes described above were responsible for converting limonene to trans-dihydrocarvone. The present study contributes to providing a foundation for the industrial production of trans-dihydrocarvone in microbial chassis cells using synthetic biology strategies. © 2021 Society of Chemical Industry.


Assuntos
Klebsiella , Terpenos , Biotransformação , Monoterpenos Cicloexânicos , Klebsiella/metabolismo , Limoneno/metabolismo , Monoterpenos/metabolismo , Oxirredução , Terpenos/metabolismo
4.
J Food Sci Technol ; 59(11): 4487-4498, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36193467

RESUMO

Nootkatone is an important functional sesquiterpene, which can be obtained by the biotransformation of valencene. It is increasingly important because of its pleasant citrus aroma and physiological effects. Yarrowia lipolytica is beneficial for biotechnology applications and has ability to transform valencene to nootkatone. High-speed counter-current chromatography (HSCCC) was used to isolate and purify the product of nootkatone in this study. The suitable two-phase solvent system was selected and the optimum separation conditions were determined. The partition coefficients of nootkatone and the separation factor between nootkatone and valencene were considered as the indexes. The results showed that there were numerous products during the transformation of valencene by Yarrowia lipolytica, and the content of nootkatone was 13.75%. The obtained nootkatone was separated by HSCCC with a solvent system n-hexane/methanol/water (5/4/1, v/v). The final purity of nootkatone was 91.61 ± 0.20% and the elution time was 290-310 min. The structure of nootkatone was identified by gas chromatography-mass spectrometry (GC-MS), infrared spectrum and nuclear magnetic resonance hydrogen spectroscopy (1H NMR). This was the first report on the separation of nootkatone from the fermentation broth by HSCCC. This study proved that HSCCC could be used as an effective method to separate and purify the nootkatone from valencene transformed by Yarrowia lipolytica with n-hexane/methanol/water (5/4/1, v/v).

5.
J Ind Microbiol Biotechnol ; 48(7-8)2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34279658

RESUMO

(+)-Nootkatone is an important functional sesquiterpene and is comprehensively used in pharmaceutical, cosmetic, agricultural and food flavor industries. However, (+)-nootkatone is accumulated trace amounts in plants, and the demand for industry is mainly met by chemical methods which is harmful to the environment. The oxygen-containing sesquiterpenes prepared using microbial methods can be considered as "natural." Microbial transformation has the advantages of mild reaction conditions, high efficiency, environmental protection, and strong stereoselectivity, and has become an important method for the production of natural spices. The microbial biosynthesis of (+)-nootkatone from the main precursor (+)-valencene is summarized in this paper. Whole-cell systems of fungi, bacteria, microalgae, and plant cells have been employed. It was described that the enzymes involved in the microbial biosynthesis of (+)-nootkatone, including cytochrome p450 enzymes, laccase, lipoxygenase, and so on. More recently, the related enzymes were expressed in microbial hosts to heterologous produce (+)-nootkatone, such as Escherichia coli, Pichia pastoris, Yarrowia lipolytica, and Saccharomyces cerevisiae. Finally, the development direction of research for realizing industrialization of microbial transformation was summarized and it provided many options for future improved bioprocesses.


Assuntos
Sesquiterpenos , Sistema Enzimático do Citocromo P-450 , Sesquiterpenos Policíclicos , Saccharomyces cerevisiae , Saccharomycetales
6.
Molecules ; 26(9)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33922023

RESUMO

Flavors and fragrances have high commercial value in the food, cosmetic, chemical and pharmaceutical industries. It is interesting to investigate the isolation and characterization of new microorganisms with the ability to produce flavor compounds. In this study, a new strain of Klebsiella sp. O852 (accession number CCTCC M2020509) was isolated from decayed navel orange (Citrus sinensis (L.) Osbeck), which was proved to be capable of converting limonene to trans-dihydrocarvone. Besides, the optimization of various reaction parameters to enhance the trans-dihydrocarvone production in shake flask was performed for Klebsiella sp. O852. The results showed that the yield of trans-dihydrocarvone reached up to 1 058 mg/L when Klebsiella sp. O852 was incubated using LB-M medium for 4 h at 36 °C and 150 rpm, and the biotransformation process was monitored for 36 h after adding 1680 mg/L limonene/ethanol (final ethanol concentration of 0.8% (v/v)). The content of trans-dihydrocarvone increased 16 times after optimization. This study provided a basis and reference for producing trans-dihydrocarvone by biotransformation.


Assuntos
Monoterpenos Cicloexânicos/metabolismo , Fermentação , Klebsiella/metabolismo , Biotransformação , Monoterpenos Cicloexânicos/química , Klebsiella/classificação , Klebsiella/efeitos dos fármacos , Klebsiella/isolamento & purificação , Limoneno/metabolismo , Limoneno/farmacologia , Filogenia , Solventes/química , Temperatura
7.
J Sci Food Agric ; 101(5): 1844-1853, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32901966

RESUMO

BACKGROUND: Male Kunming mice were divided into a normal diet group (control group) and a high-fat diet group (HF group) (185 g·kg-1 protein, 600 g·kg-1 fat and 205 g·kg-1 carbohydrate). After 8 weeks' feeding, behavioral indicators and biochemical indicators in serum were determined. The double-bottle preference experiment was used to study the preferences of mice for five sweeteners. The monoamine neurotransmitter content, gene expression related to dopamine (DA), and opioid receptors were also determined. RESULTS: The body weight of the mice in the HF group increased significantly (P < 0.05) after 36 days compared with the control group. The feed intake of the HF group increased sharply in the first 12 days, and then it became basically unchanged. The preference of the HF group for all of the five sweeteners was highly significantly lower (P < 0.01) than that of the control group. Depression-related behavior was observed in the HF group mice. The triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDLC) content in the HF group were very much higher (P < 0.01) than those of the control group. The gene expression related to DA and opioid receptor in the HF group was significantly lower than that of the control group, except for preproenkephalin (PENK). CONCLUSIONS: In summary, this study suggested that a long-term high-fat diet could result in a decrease in the preference for sweeteners and could result in a state of reward hypofunction in mice. © 2020 Society of Chemical Industry.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Gorduras na Dieta/metabolismo , Edulcorantes/metabolismo , Animais , Peso Corporal , LDL-Colesterol/metabolismo , Gorduras na Dieta/efeitos adversos , Ingestão de Alimentos , Masculino , Camundongos , Neurotransmissores/metabolismo , Receptores Opioides/genética , Receptores Opioides/metabolismo , Edulcorantes/efeitos adversos , Triglicerídeos/metabolismo
8.
J Food Sci Technol ; 58(6): 2227-2236, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33967319

RESUMO

This study focused on the effect of short-term intake of sweeteners on feed intake, solution consumption and neurotransmitters release on mice. The results showed that the free drinking of 10 mM sucralose solution, 100 mM maltose solution, 3 mM saccharin solution and 3 g/L stevioside solution for 32 days will not affect the normal development of the body weight and feed intake of the mice. The consumption of maltose solution was significantly higher than that of the other sweeteners. The leptin and insulin levels increased significantly after the short-term intake of these four sweeteners. The dopamine (DA) content in the whole brain of the mice increased significantly only in the maltose group. These results indicate that the short-term intake of the preferred concentrations of maltose, stevioside, sucralose and saccharin will not affect the body weight and feed intake of the mice. Mice prefer maltose solution to other sweeteners solutions. The 100 mM maltose solution and 3 mM saccharin solution could result in the oxidative stress on mice after 32 days' short-term intake. Compared with other sweeteners, only sugars that could be broken down into small molecules of glucose might have a positive effect on dopamine levels.

9.
J Food Sci Technol ; 57(1): 113-121, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31975714

RESUMO

Four natural sweeteners (sucrose, stevioside, maltose and xylitol) and six artificial sweeteners (acesulfame, sucralose, aspartame, cyclamate, saccharin and neotame) were used to study the effects of different sweeteners on the behavior and neurotransmitter release of mice with two-bottle preference experiments. The results showed that very significant preference behavior for 8% sucrose solution, 0.3% stevioside solution, 10 mM acesulfame, 10 mM sucralose and 10 mM aspartame solutions (p < 0.01) was observed on mice. Long-term exposure of sucrose solution and acesulfame solution can affect the behavioral indicators such as solution consumption, feed intake, body weight and the release of neurotransmitters in mice. The solution consumption and the release of neurotransmitters were significantly greater (p < 0.05) than that of the control group (water group), but there was no significant difference in feed intake. The acesulfame-A and acesulfame-B groups had no significant difference on the consumption of solution and feed intake, but there was significant difference in the release of neurotransmitters. The result also showed that different sweetener solutions with similar sweetness had the same effect on the neurotransmitters release, and it can be inferred that mice have an addictive behavioral characteristic to sucrose.

10.
Molecules ; 24(24)2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31817260

RESUMO

An in situ tracing study based on solid-phase microextraction (SPME) was conducted to investigate the uptake and elimination of organophosphorus pesticides in apples. A matrix-compatible polydimethylsiloxane/poly(styrene-co-divinylbenzene)/polydimethylsiloxane fiber was produced to meet the needs of in situ sampling. The fiber had high extraction ability, good sensitivity and accuracy with respect to the analytes in apple pulp, and could be used 85 times. Although the sampling rate was changing over time, quantification was still achieved by the sampling rate calibration method. Some factors that affect its applicability were studied. The limits of detection were 0.18 ng/g for diazinon and 0.20 ng/g for chlorpyrifos, rather lower than the maximum residue limits of the National Food Safety Standard of China (GB 2763-2016) and the European Commission (Reg.(EU) No 834/2013, 2018/686). The accuracy of in situ SPME quantification was verified by comparing with the results obtained by the traditional liquid-liquid extraction method. In this work, the in situ sampling method is developed using apples, diazinon, and chlorpyrifos as a model system; however, this method can be used for in vivo analysis of fruits and vegetables for nutrition and safety monitoring.


Assuntos
Malus/química , Compostos Organofosforados/análise , Praguicidas/análise , Microextração em Fase Sólida/métodos , Calibragem , Clorpirifos/análise , Cromatografia Gasosa , Diazinon/análise , Temperatura
11.
J Sci Food Agric ; 99(8): 4019-4028, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30729524

RESUMO

BACKGROUND: The intestinal microbiota has a wide variety of functions in the host. A positive effect of plant extract on intestinal microbiota in animals has been reported. However, the effect of orange essential oil and its components limonene, linalool and citral on intestinal microflora in mice has seldom been reported. The effects of intragastric administration of orange essential oil and limonene, linalool and citral on intestinal microflora and biochemical indexes in mice were studied. RESULTS: The effect of essential oil, linalool and citral on immune organ index (spleen and thymus index), IgM and IL-2 was not significant (P > 0.05). A significant increase (P < 0.05) of H+ K+ -ATPase activity, IgA, IgG, and IL-2 in the limonene group was observed when compared with the control group. Orange essential oil, limonene, linalool and citral could significantly reduce the content of short-chain fatty acids in the cecum and colon of mice. Principal coordinates analysis showed that intestinal bacterial structure of limonene group cecum and colon was apparently separated from other groups. The relative abundance of Lactobacillus in cecum and colon in essential oil, limonene, linalool and citral groups was higher than that in the control group. CONCLUSIONS: Orange essential oil and limonene, linalool and citral could affect the intestinal microflora of mice, and enhance the relative abundance of Lactobacillus. The intestinal bacterial structure of cecum and colon in the limonene group was quite different from other groups. This indicated a more obvious effect of limonene on intestinal bacteria, also resulting in significant changes in blood immune index and short-chain fatty acids in mice. © 2019 Society of Chemical Industry.


Assuntos
Citrus sinensis/química , Microbioma Gastrointestinal/efeitos dos fármacos , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/metabolismo , Ácidos Graxos Voláteis/metabolismo , Intestinos/imunologia , Intestinos/microbiologia , Masculino , Camundongos , Óleos Voláteis/química , Filogenia , Extratos Vegetais/química , Baço/efeitos dos fármacos , Baço/imunologia , Timo/efeitos dos fármacos , Timo/imunologia
12.
J Cosmet Sci ; 69(4): 279-291, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30311903

RESUMO

Five distyryl-type fluorescent whitening agents (FWA85, 210, 220, 351, and 353) were determined in cosmetics and liquid detergent by high-performance liquid chromatography with diode array detector in tandem with fluorescence detector. The samples were extracted with ultrasound in 33% acetonitrile for 10 minutes and the components were determined by ion-pair chromatography on an MG C18 column. The limits of detection were from 0.01 to 0.1 mg·kg-1 and the limits of quantification were from 0.04 to 0.4 mg·kg-1. The recovery was from 80.7 to 103.3%. A linear relationship was present from 0.10 to 100 µg·ml-1 of FWAs. The protocol was simple, sensitive, selective, and was successfully applied to analyze distyryl-type FWAs in cosmetics and liquid detergent. FWA351 and FWA85 were detected in several samples with the concentrations of 19.4-1,130 mg·kg-1.


Assuntos
Clareadores/análise , Cromatografia Líquida de Alta Pressão/métodos , Cosméticos/química , Detergentes/química , Espectrometria de Fluorescência/métodos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
13.
J Food Sci Technol ; 55(11): 4530-4543, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30333650

RESUMO

This study focused on the changes of physicochemical and microbiological properties and aroma compounds of freshly-squeezed orange juice during storage at different temperatures. Aroma compounds were analyzed by solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). The results showed that the total aerobic plate counts of orange juice stored at room temperature and 37 °C was far more than 4 °C. Totally 33 aroma compounds were determined in these orange juices. Significant differences on the aroma compounds in orange juices stored at different temperatures were observed in the present study. Most of the terpenes decreased at 4 °C after 15 days' storage, while 10 and 8 terpenes increased during storage at room temperature and 37 °C. α-Terpineol and p-vinylguaiacol were the only off-flavor compounds found in juice stored at 4 °C and room temperature at late storage respectively. While terpinen-4-ol, 4-ethylguaiacol and p-vinylguaiacol were found in juice stored at 37 °C at late storage. α-Terpineol was the only off-flavor compound found in orange juice stored at 4 °C.

14.
J Food Sci Technol ; 55(10): 4223-4231, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30228421

RESUMO

The present study focused on the effect of olive oil on Ostwald ripening of flavor nanoemulsions. The release of the aroma compounds from the nanoemulsion system was also investigated. The results showed that the droplets size of the nanoemulsions decreased sharply first and then kept stable with the increase of Tween 80. The optimum surfactant/cosurfactant (Km) ratio was determined at 7:1. The average particle size of nanoemulsion was 39.22 nm. The polydispersity index (PDI) was 0.242 nm, and the particle size distribution was in the range of 20-150 nm at the optimum Km. The stability of the nanoemulsions was improved after the addition of olive oil, and it increased noticeably with the increase of olive oil. The addition of olive oil could help to stabilize the emulsions and hamper Ostwald ripening. All the 11 aroma compounds in the nanoemulsions were detected after 24-h storage. While only 5 aroma compounds were found after 48-h storage, and α-pinene and ß-myrcene were the only two aroma compounds detected after 72-h storage with low contents of 1.41 and 0.5 mg/L. The addition of olive oil inhibited the release of the aroma compounds from the nanoemulsion system. The released ethyl acetate was reduced by 48% after the addition of 10% olive oil. Significant decrease on the release of α-pinene and nonanal was observed after the addition of 3% olive oil. And the decrease was also observed on the release of ß-myrcene, D-limonene, α-terpineol, decanal and eugenol when the olive oil content was ≥ 5%. However, benzyl alcohol, ß-ionone and 1-octanol showed no significant changes with the increase of olive oil. This indicated that the addition of olive oil could provide greater retention of the aroma compounds in the nanoemulsions.

15.
J Ind Microbiol Biotechnol ; 43(10): 1481-95, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27538968

RESUMO

This study focused on the differences in protein expression at various periods during limonene biotransformation by Penicillium digitatum DSM 62840. A total of 3644 protein-species were quantified by iTRAQ during limonene biotransformation (0 and 12 h). A total of 643 proteins were differentially expressed, 316 proteins were significantly up-regulated and 327 proteins were markedly down-regulated. GO, COG, and pathway enrichment analysis showed that the differentially expressed proteins possessed catalytic and binding functions and were involved in a variety of cellular and metabolic process. Furthermore, the enzymes involved in limonene transformation might be related to cytochrome P-450. This study provided a powerful platform for further exploration of biotransformation, and the identified proteins provided insight into the mechanism of limonene transformation.


Assuntos
Cicloexenos/metabolismo , Proteínas Fúngicas/metabolismo , Penicillium/metabolismo , Terpenos/metabolismo , Biotransformação , Cromatografia Líquida , Cicloexenos/química , Limoneno , Proteômica , Espectrometria de Massas em Tandem , Terpenos/química
16.
Molecules ; 21(4): 511, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-27110762

RESUMO

This study aimed to determine the influence of different emulsifiers or xanthan-emulsifier systems on the release of aroma compounds. Solid-phase microextraction (SPME) and GC-MS were used to study the effects of varying concentrations of xanthan gum, sucrose fatty acid ester, Tween 80 and soybean lecithin on the release of seven aroma compounds. The effects of the emulsifier systems supplemented with xanthan gum on aroma release were also studied in the same way. The results showed varying degrees of influence of sucrose fatty acid ester, soybean lecithin, Tween 80 and xanthan gum on the release of aroma compounds. Compared with other aroma compounds, ethyl acetate was more likely to be conserved in the solution system, while the amount of limonene released was the highest among these seven aroma compounds. In conclusion, different emulsifiers and complexes showed different surface properties that tend to interact with different aroma molecules. The present studies showed that the composition and structure of emulsifiers and specific interactions between emulsifiers and aroma molecules have significant effects on aroma release.


Assuntos
Emulsificantes/química , Aditivos Alimentares/química , Glycine max/química , Odorantes/análise , Indústria de Processamento de Alimentos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Lecitinas/química , Polissacarídeos Bacterianos/química , Polissorbatos/química , Microextração em Fase Sólida/métodos , Sacarose/química , Propriedades de Superfície
17.
J Sci Food Agric ; 96(3): 954-61, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25777262

RESUMO

BACKGROUND: In this study, (R)-(+)-limonene biotransformation using three fungal strains was compared. Penicillium digitatum DSM 62840 was distinguished for its capacity to transform limonene into α-terpineol with high regioselectivity. Growth kinetics in submerged liquid culture and the effects of growth phase and contact time on biotransformation were studied using this strain. Substrate concentration, co-solvent selection, and cultivation conditions were subsequently optimised. RESULTS: The maximum concentration of α-terpineol (833.93 mg L(-1)) was obtained when the pre-culture medium was in medium log-phase by adding 840 mg L(-1) substrate dissolved in ethanol and cultivation was performed at 24 °C, 150 rpm, and pH 6.0 for 12 h. Addition of small amounts of (R)-(+)-limonene (84 mg L(-1)) at the start of fungal log-phase growth yielded a 1.5-fold yield of α-terpineol, indicating that the enzyme was inducible. CONCLUSION: Among these three strains tested, P. digitatum DSM 62840 was proved to be an efficient biocatalyst to transform (R)-(+)-limonene to α-terpineol. Further studies revealed that the optimal growth phase for biotransformation was in the medium log phase of this strain. The biotransformation represented a wide tolerance of temperature; α-terpineol concentration underwent no significant change at 8-32 °C. The biotransformation could also be performed using resting cells.


Assuntos
Cicloexenos/metabolismo , Aditivos Alimentares/metabolismo , Monoterpenos/metabolismo , Penicillium/metabolismo , Terpenos/metabolismo , Biotransformação , Monoterpenos Cicloexânicos , Humanos , Limoneno
18.
Pain Ther ; 13(4): 883-907, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38834881

RESUMO

INTRODUCTION: Postherpetic neuralgia (PHN), a complication of herpes zoster, significantly impacts the quality of life of affected patients. Research indicates that early intervention for pain can reduce the occurrence or severity of PHN. This study aims to develop a predictive model and scoring table to identify patients at risk of developing PHN following acute herpetic neuralgia, facilitating informed clinical decision-making. METHODS: We conducted a retrospective review of 524 hospitalized patients with herpes zoster at The First Affiliated Hospital of Zhejiang Chinese Medical University from December 2020 to December 2023 and classified them according to whether they had PHN, collecting a comprehensive set of 30 patient characteristics and disease-related indicators, 5 comorbidity indicators, 2 disease score values, and 10 serological indicators. Relevant features associated with PHN were identified using the least absolute shrinkage and selection operator (LASSO). Then, the patients were divided into a training set and a test set in a 4:1 ratio, with comparability tested using univariate analysis. Six models were established in the training set using machine learning methods: support vector machines, logistic regression, random forest, k-nearest neighbor, gradient boosting, and neural network. The performance of these models was evaluated in the test set, and a nomogram based on logistic regression was used to create a PHN prediction score table. RESULTS: Eight non-zero characteristic variables selected from the LASSO regression results were included in the model, including age [area under the curve (AUC) = 0.812, p < 0.001], Numerical Rating Scale (NRS) (AUC = 0.792, p < 0.001), receiving treatment time (AUC = 0.612, p < 0.001), rash recovery time (AUC = 0.680, p < 0.001), history of malignant tumor (AUC = 0.539, p < 0.001), history of diabetes (AUC = 0.638, p < 0.001), varicella-zoster virus immunoglobulin M (AUC = 0.620, p < 0.001), and serum nerve-specific enolase (AUC = 0.659, p < 0,001). The gradient boosting model outperformed other classifier models on the test set with an AUC of 0.931, 95% confidence interval (CI) (0.882-0.980), accuracy of 0.886 (95% CI 0.809-0.940). In the test set, our predictive scoring table achieved an AUC of 0.820 (95% CI 0.869-0.970) with accuracy of 0.790 (95% CI 0.700-0.864). CONCLUSION: This study presents a methodology for predicting the development of postherpetic neuralgia in shingles patients by analyzing historical case data, employing various machine learning techniques, and selecting the optimal model through comparative analysis. In addition, a logistic regression model has been used to create a scoring table for predicting the postherpetic neuralgia.

19.
Front Med (Lausanne) ; 11: 1400741, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38813379

RESUMO

Background: The relationship between plaque psoriasis and both MASLD and lean MASLD has not been sufficiently explored in the current literature. Method: This retrospective and observational study was carried out from January 2021 to January 2023 at The First Affiliated Hospital of Zhejiang Chinese Medical University. Patients diagnosed with plaque psoriasis and a control group consisting of individuals undergoing routine physical examinations were enrolled. The incidence of MASLD and lean MASLD among these groups was compared. Additionally, patients with plaque psoriasis were divided into those with MASLD, those with lean MASLD, and a control group with only psoriasis for a serological comparative analysis. Results: The incidence of MASLD in the observation group and the control group was 43.67% (69/158) and 22.15% (35/158), respectively (p < 0.01). Furthermore, the incidence of lean MASLD within the observation group and the control group was 10.76% (17/158) and 4.43% (7/158), respectively (p < 0.01). After controlling for potential confounding variables, plaque psoriasis was identified as an independent risk factor for MASLD with an odds ratio of 1.88 (95% cl: 1.10-3.21). In terms of serological comparison, compared to the simple psoriasis group, we observed a significant elevation in the tumor marker CYFRA21-1 levels in both groups compared to the control group with simple psoriasis (p < 0.01). Moreover, the MASLD group exhibited elevated levels of inflammatory markers and psoriasis score, whereas these effects were mitigated in the lean MASLD group. Conclusion: The prevalence of MASLD and lean MASLD is higher among patients with psoriasis. Those suffering from psoriasis along with MASLD show increased psoriasis scores and inflammatory markers compared to those without metabolic disorders. MASLD likely worsens psoriasis conditions, indicating the necessity of targeted health education for affected individuals to reduce the risk of MASLD, this education should include guidelines on exercise and diet. In serological assessments, elevated levels of cytokeratin 19 fragment (CYFRA21-1) were noted in both MASLD and lean MASLD groups, implying a potential synergistic role between psoriasis and MASLD.

20.
BMC Genomics ; 14: 276, 2013 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-23617778

RESUMO

BACKGROUND: Tibial dyschondroplasia (TD) is a common skeletal disorder in broiler chickens. It is characterized by the presence of a non-vascularized and unmineralized cartilage in the growth plate. Previous studies have investigated differential expression of genes related to cartilage development during latter stages of TD. The aim of our study was to identify differentially expressed genes (DEGs) in the growth plate of broiler chickens, which were associated with early stage TD. We induced TD using tetramethylthiuram disulfide (thiram) for 1, 2, and 6 days and determined DEGs with chicken Affymetrix GeneChip assays. The identified DEGs were verified by quantitative polymerase chain reaction (qPCR) assays. RESULTS: We identified 1630 DEGs, with 82, 1385, and 429 exhibiting at least 2.0-fold changes (P < 0.05) at days 1, 2, and 6, respectively. These DEGs participate in a variety of biological processes, including cytokine production, oxidation reduction, and cell surface receptor linked signal transduction on day 1; lipid biosynthesis, regulation of growth, cell cycle, positive and negative gene regulation, transcription and transcription regulation, and anti-apoptosis on day 2; and regulation of cell proliferation, transcription, dephosphorylation, catabolism, proteolysis, and immune responses on day 6. The identified DEGs were associated with the following pathways: neuroactive ligand-receptor interaction on day 1; synthesis and degradation of ketone bodies, terpenoid backbone biosynthesis, ether lipid metabolism, JAK-STAT, GnRH signaling pathway, ubiquitin mediated proteolysis, TGF-ß signaling, focal adhesion, and Wnt signaling on day 2; and arachidonic acid metabolism, mitogen-activated protein kinase (MAPK) signaling, JAK-STAT, insulin signaling, and glycolysis on day 6. We validated seven DEGs by qPCR. CONCLUSIONS: Our findings demonstrate previously unrecognized changes in gene transcription associated with early stage TD. The DEGs we identified by microarray analysis will be used in future studies to clarify the molecular pathogenic mechanisms of TD. From these findings, potential pathways involved in early stage TD warrant further investigation.


Assuntos
Osteocondrodisplasias/genética , Doenças das Aves Domésticas/genética , Animais , Galinhas/genética , Regulação para Baixo , Lâmina de Crescimento/crescimento & desenvolvimento , Lâmina de Crescimento/patologia , Carne , Osteocondrodisplasias/induzido quimicamente , Osteocondrodisplasias/metabolismo , Análise Serial de Proteínas , Tiram , Tíbia/patologia , Transcriptoma
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