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1.
Artículo en Inglés | MEDLINE | ID: mdl-38409719

RESUMEN

BACKGROUND: As a malignant tumor, osteosarcoma (OS) ranks first place among adolescent cancers and is susceptible to developing resistance to chemotherapeutic agents. Differently, traditional Chinese medicine (TCM) has multiple pharmacodynamic targets and complex biological components, which can inhibit tumor survival and drug resistance and gradually play an important role in the treatment of sarcoma. METHODS: This study is to systematically evaluate the safety and efficacy of TCM combined with chemotherapy performed in the clinical treatment of OS. Based on multiple mainstream databases, eleven articles on the relationship between natural products and chemotherapy involving 656 patients were selected from all the literature published as of June 2022. Revman 5.4 software was used for a comprehensive search analysis, supplemented by established exclusion criteria, the Jadad scale, and the evaluation methods provided by Cochrane. RESULTS: The efficiency of TCM combined with chemotherapy was significantly increased compared with chemical drugs alone [OR=2.56, 95% CI (1.36,4.79), Z=2.92, P=0.003]. Meanwhile, the adverse reactions such as nausea and vomiting, hepatotoxicity, and hematological changes caused by chemical drugs were alleviated correspondingly. CONCLUSION: This study indicates that the mode of TCM combined with chemotherapy sheds light on the clinical treatment of OS, which is much better than the one-way mode.

2.
Bioresour Technol ; 382: 129154, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37172743

RESUMEN

The development of organic acid pretreatments from biological sources is essential to facilitate the progress of green and sustainable chemistry. In this study, the effectiveness of mandelic acid pretreatment (MAP) was analyzed for eucalyptus hemicellulose separation. 83.66% of xylose was separated under optimal conditions (temperature: 150 °C; concentration: 6.0 wt%; time: 80 min). The hemicellulose separation selectivity is higher than acetic acid pretreatment (AAP). The stable and effective separation efficiency (56.55%) is observed even after six reuses of the hydrolysate. Higher thermal stability, larger crystallinity index and optimized surface element distribution in the samples were demonstrated by MAP. Lignin condensation is effectively inhibited through MAP, as determined from the structural of different lignin. In particular, the demethoxylation of lignin by MA was found. These results open up a new way to construct a novel organic acid pretreatment for separating hemicellulose with high efficiency.


Asunto(s)
Lignina , Polisacáridos , Lignina/química , Polisacáridos/química , Ácidos/química , Compuestos Orgánicos , Hidrólisis , Biomasa
3.
Bioresour Technol ; 364: 128082, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36216284

RESUMEN

Organic acid pretreatments can efficiently separate biomass-based hemicellulose and selectively produce hemicellulose-derived sugars. In this study, hemicellulose is separation as xylose, oligosaccharides in the tropic acid-catalyzed hydrothermal pretreatment of eucalyptus. The maximum yield of hemicellulose-derived sugars (85.78 %) with 71.25 % xylose selectivity (based on the total xylose in raw material) was achieved in the hydrolysate under optimal conditions (5 % TA, 160 ℃, 80 min). The yield of hemicellulose-derived sugar and the separation yield of hemicellulose increased by 11.06 % and 11.45 % compared with glycolic acid pretreatment in the similar severity factor. The separation yield of cellulose and lignin was decreased by 4.23 % and 0.98 %, respectively. This resulted in residual solids with higher biological stability (higher fiber crystallinity index, higher thermal stability, and higher lignin content). Therefore, higher hemicellulose separation selectivity and rich hemicellulose-derived sugars were obtained using TA pretreatment. The work would bring up a new method for biomass refining.

4.
Bioresour Technol ; 355: 127304, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35562023

RESUMEN

Aromatic and hydroxyl acid treatments demonstrate their respective characteristics for the separation of lignocellulosic biomass. In this study, the effect of salicylic acid (SA-A) treatment on the separation of eucalyptus components with both aromatic and hydroxyl acid properties was analyzed. The optimal conditions were SA-A concentration 9.0%, reaction temperature 140 °C and time 75 min. The separation yield of xylose was 85.93%. The separation of cellulose and lignin was inhibited by SA-A treatment in contrast to the separation by glycolic acid and p-toluenesulfonic acid treatment. Moreover, SA-A treatment resulted in a larger fiber crystallinity index and higher thermal stability. The SA-A-treated samples contained lignin that was rich in ß-O-4 and hydroxyl groups. The degradation and condensation of lignin was inhibited. The selectivity of aromatic acids for separating hemicellulose and protecting the lignin structure using hydroxy acids was demonstrated. Thus, new and efficient organic acid treatments can be developed.


Asunto(s)
Eucalyptus , Ácidos , Biomasa , Eucalyptus/química , Hidroxiácidos , Lignina/química , Polisacáridos , Ácido Salicílico
5.
Polymers (Basel) ; 14(7)2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35406206

RESUMEN

The preparation of bio-oil through biomass pyrolysis is promoted by different demineralization processes to remove alkali and alkaline earth metal elements (AAEMs). In this study, the hydrothermal pretreatment demineralization was optimized by the response surface method. The pretreatment temperature, time and pH were the response elements, and the total dissolution rates of potassium, calcium and magnesium were the response values. The interactions of response factors for AAEMs removal were analyzed. The interaction between temperature and time was significant. The optimal AAEMs removal process was obtained with a reaction temperature of 172.98 °C, time of 59.77 min, and pH of 3.01. The optimal dissolution rate of AAEMs was 47.59%. The thermal stability of eucalyptus with and without pretreatment was analyzed by TGA. The hydrothermal pretreatment samples exhibit higher thermostability. The composition and distribution of pyrolysis products of different samples were analyzed by Py-GC/MS. The results showed that the content of sugars and high-quality bio-oil (C6, C7, C8 and C9) were 60.74% and 80.99%, respectively, by hydrothermal pretreatment. These results show that the removal of AAEMs through hydrothermal pretreatment not only improves the yield of bio-oil, but also improves the quality of bio-oil and promotes an upgrade in the quality of bio-oil.

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