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1.
Bioresour Technol ; 364: 128053, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36195216

RESUMO

Anaerobic digestion of kitchen waste with grass after hyperthermophilic pretreatment was performed in semi-continuously operated reactors. The greatest methane yield of 293 NmlCH4/gVS (volatile solids) was reported for the mixture of both substrates at 55 °C with a solids retention time of 30 d and the corresponding organic lading rate of 1.72 kgVS/m3/d. In contrast, pretreated grass subjected to thermophilic digestion produced only 131 NmlCH4/gVS. However, when mesophilic conditions were applied, the digestion process turned into dark fermentation, especially visible for the mixture. Metagenomic analysis revealed the dominance Ruminococcaceae, Atopobiaceae and Lactobacillaceae at a family level in mesophilic processes, whereas Petrotogaceae, Synergistaceae, Hungateiclostridiaceae, Planococcaceae and two methanogens Methanosarcinaceae and Methanothermobacteriaceae were the most frequent microbes of thermophilic digestion. Kitchen waste can successfully be co-digested with hyperthermophilically pretreated grass at high loading rates, however the digesters must be operated at thermophilic temperatures.

2.
Molecules ; 27(14)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35889215

RESUMO

The isolation of microorganisms was performed from digestate from the process of the anaerobic digestion (AD) of grass after hyperthermophilic pretreatment. The bacterium that was isolated and identified was Coprothermobacter sp. Using the isolated bacteria, an AD process on fresh grass (GB) and pretreated grass (PGB) was carried out with 10% of its addition. The highest methane yield of 219 NmlCH4/gVS was recorded for PGB at 55 °C. In contrast, fresh grass subjected to thermophilic digestion produced only 63 NmlCH4/gVS. Due to the addition of bacteria in the AD process, an increase in the efficiency of hydrogen and methane production was observed in both fresh grass and grass after pretreatment.


Assuntos
Poaceae , Anaerobiose , Bactérias , Bactérias Anaeróbias , Reatores Biológicos , Digestão , Firmicutes , Metano
3.
Ind Crops Prod ; 175: 114265, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34815622

RESUMO

Tea and coffee contain numerous polyphenolic compounds that exhibit health-promoting properties for humans, including antioxidant and neuroprotective properties, and can also take part in the treatment of covid-19 and improve fertility. This review, presents the activity of polyphenols found in different types of tea and coffee and describes the effects of tea fermentation and coffee roasting on their polyphenol composition and antioxidant properties. Polyphenol oxidase activity is reduced in the fermentation process; therefore black tea contains significantly less polyphenolic compounds compared to green and white tea. Epigallocatechin-3-gallate - a polyphenol from tea - effectively has been shown to inhibit the activity of SARS-CoV-2 as it blocked binding of coronavirus 2 to human angiotensin converting enzyme 2, decreased the expression of inflammatory factors in the blood, including tumor necrosis factor-α and interleukin-6, and significantly increased the overall fertilization efficiency in animals. Coffee roasting process influences both the content of polyphenols and the oxidative activity. The lowest levels of active compounds such as caffeine, chlorogenic acid and coffee acids are identified in roasted coffee beans. On the other hand, light coffee and green coffee show the strongest cytotoxic potential and antioxidant properties, and thus the greatest ability to decrease apoptosis by stopping the cell cycle in the S phase. Proteins, such as components of milk, can strongly bind/interact with phenolic compounds (especially, the CGAs) contain in coffee, which may explain the negative influence of milk on its antioxidant properties. Coffee polyphenols have also antiproliferative and antiesterase activities, which may be important in prevention of cancer and neurodegenerative disorders, respectively. In this review, biological properties of tea and coffee polyphenols, observed mainly in in vitro studies have been described. Based on these findings, future directions of the research works on these compounds have been suggested.

4.
Bioresour Technol ; 335: 125264, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34004562

RESUMO

Anaerobic digestion of garden waste was investigated in a two-stage process consisting of hyperthermophilic pretreatment followed by mesophilic or thermophilic fermentation. The greatest digestion performance was achieved when the substrates were first treated at 70 °C for 3 days with no inoculation, and then mixed with inoculum (anaerobic sludge) and subjected to anaerobic digestion at 55 °C. Under such conditions, the maximum methane and hydrogen yields from grass were 517 NmlCH4/kgVS and 52 NmlH2/kgVS, whereas the corresponding values for leaves were 421 NmlCH4/kgVS and 23 NmlH2/kgVS, and these figure were far greater than the yields obtained in experiments with no hyperthermophilic stage. A metagenomic analysis of hyperthermophilic environments revealed the appearance of thermophilic and hyperthermophilic bacteria showing hydrolytic activity against lignocellulosic materials, including Caldicellulosiruptor, Thermovenabulum, Thermoanaerobacter, Moorella, Tepimicrobium, Geobacillus and Thermobacillus at a genus level. A noticeable methane production in the hyperthermophilic stage could be linked to the presence of Methanothermobacter sp.


Assuntos
Reatores Biológicos , Metano , Anaerobiose , Jardins , Hidrogênio , Esgotos
5.
Phytother Res ; 34(8): 1992-2005, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32141677

RESUMO

Recently, many studies have been conducted trying to explain the molecular mechanism of curcumin action in various pathological states of the cell and the organism. Curcumin is considered to play a role in the regulation of T-lymphocytes function in the lymphoid tissue of the large intestine, apoptosis of the human papilloma and the activity of the 26S proteasome, and p53 level. Research works have shown that curcumin in tumor can regulate reactive oxygen species (ROS) and cytosolic calcium ion level as well as affect other signaling molecules [nuclear factor kappa B (NF-KB), cytokines] triggering endoplasmic reticulum and mitochondrial stress, and thus contributing to death of cancer cells. Curcumin can also arrest of the cell cycle in the G2/M phase leading to apoptosis and/or reduction in cancer cells proliferation. Moreover, curcumin is capable of crossing the blood-brain barrier, and thus it may protect the neurons from oxidative stress and inflammation. Finally, curcumin may play a role in cardiological protection and it is possible to use it in the protection of liver and spleen against oxidative and inflammatory injury. Among signaling pathways regulated by curcumin, the most important seem to be those related with regulation of oxidative stress and inhibition of NF-кB activity.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Curcumina/uso terapêutico , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Curcumina/farmacologia , Humanos , Camundongos , Estrutura Molecular , Ratos , Transdução de Sinais
6.
Immunopharmacol Immunotoxicol ; 40(3): 212-218, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29486614

RESUMO

Amygdalin, named as 'laetrile' and 'vitamin B-17' was initially supposed to be a safe drug for cancer treatment and was recognized by followers of natural medicine since it has been considered to be hydrolyzed only in cancer cells releasing toxic hydrogen cyanide (HCN), and thus destroying them. Unfortunately, current studies have shown that HCN is also released in normal cells, therefore it may not be safe for human organism. However, there have still been research works conducted on anti-cancer properties of this compound. In vitro experiments have shown induction of apoptosis by amygdalin as a result of increased expression of Bax protein and caspase-3 and reduced expression of antiapoptotic BcL-2protein. Amygdalin has also been shown to inhibit the adhesion of breast cancer cells, lung cancer cells and bladder cancer cells by decreased expression of integrin's, reduction of catenin levels and inhibition of the Akt-mTOR pathway, which may consequently lead to inhibition of metastases of cancer cells. It has also been revealed that amygdalin in renal cancer cells increased expression of p19 protein resulting in inhibition of cell transfer from G1-phase to S-phase, and thus inhibited cell proliferation. Other studies have indicated that amygdalin inhibits NF-kß and NLRP3 signaling pathways, and consequently has anti-inflammatory effect due to reducing the expression of proinflammatory cytokines such as pro-IL-1ß. Moreover, the effect of amygdalin on TGFß/CTGF pathway, anti-fibrous activity and expression of follistatin resulting in activation of muscle cells growth has been reported. This compound might be applicable in the treatment of various cancer cell types.


Assuntos
Amigdalina/uso terapêutico , Fase G1/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Neoplasias/biossíntese , Neoplasias , Fase S/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Amigdalina/farmacocinética , Animais , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia
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