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1.
Int J Biol Macromol ; 242(Pt 2): 124841, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37182628

ABSTRACT

Depending on its physicochemical properties and antibacterial activities, chitosan can have a wide range of applications in food, pharmaceutical, medicine, cosmetics, agriculture, and aquaculture. In this experimental study, chitosan was extracted from shrimp waste through conventional extraction, microwave-assisted extraction, and conventional extraction under microwave process conditions. The effects of the heating source on the physicochemical properties and antibacterial activity were investigated. The results showed that the heating process parameters affected the physicochemical properties considerably. The conventional procedure yielded high molecular weight chitosan with a 12.7 % yield, while the microwave extraction procedure yielded a porous medium molecular weight chitosan at 11.8 %. The conventional extraction under microwave process conditions led to medium molecular weight chitosan with the lowest yield (10.8 %) and crystallinity index (79 %). Antibacterial assessment findings revealed that the chitosan extracted using the conventional method had the best antibacterial activity in the agar disk diffusion assay against Listeria monocytogenes (9.48 mm), Escherichia coli. (8.79 mm), and Salmonella Typhimurium (8.57 mm). While the chitosan obtained by microwave-assisted extraction possessed the highest activity against E. coli. (8.37 mm), and Staphylococcus aureus (8.05 mm), with comparable antibacterial activity against S. Typhimurium (7.34 mm) and L. monocytogenes (6.52 mm). Moreover, the minimal inhibitory concentration and minimal bactericidal concentration assays demonstrated that among the chitosan samples investigated, the conventionally-extracted chitosan, followed by the chitosan extracted by microwave, had the best antibacterial activity against the target bacteria.


Subject(s)
Chitosan , Animals , Chitosan/pharmacology , Chitosan/chemistry , Microwaves , Escherichia coli , Crustacea , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Seafood
2.
Biotechnol Adv ; 66: 108172, 2023 09.
Article in English | MEDLINE | ID: mdl-37169103

ABSTRACT

Chitin, as the main component of the exoskeleton of Arthropoda, is a highly available natural polymer that can be processed into various value-added products. Its most important derivative, i.e., chitosan, comprising ß-1,4-linked 2-amino-2-deoxy-ß-d-glucose (deacetylated d-glucosamine) and N-acetyl-d-glucosamine units, can be prepared via alkaline deacetylation process. Chitosan has been used as a biodegradable, biocompatible, non-antigenic, and nontoxic polymer in some in-vitro applications, but the recently found potentials of chitosan for in-vivo applications based on its biological activities, especially antimicrobial, antioxidant, and anticancer activities, have upgraded the chitosan roles in biomaterials. Chitosan approval, generally recognized as a safe compound by the United States Food and Drug Administration, has attracted much attention toward its possible applications in diverse fields, especially biomedicine and agriculture. Despite some favorable characteristics, the chitosan's structure should be customized for advanced applications, especially due to its drawbacks, such as low drug-load capacity, low solubility, high viscosity, lack of elastic properties, and pH sensitivity. In this context, derivatization with relatively inexpensive and highly available mono- and di-saccharides to soluble branched chitosan has been considered a "game changer". This review critically scrutinizes the emerging technologies based on the synthesis and application of lactose- and galactose-modified chitosan as two important chitosan derivatives. Some characteristics of chitosan derivatives and biological activities have been detailed first to understand the value of these natural polymers. Second, the saccharide modification of chitosan has been discussed briefly. Finally, the applications of lactose- and galactose-modified chitosan have been scrutinized and compared to native chitosan to provide an insight into the current state-of-the research for stimulating new ideas with the potential of filling research gaps.


Subject(s)
Anti-Infective Agents , Chitosan , Chitosan/chemistry , Lactose , Galactose , Biocompatible Materials/chemistry , Anti-Infective Agents/chemistry
3.
Int J Biol Macromol ; 239: 124210, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37001778

ABSTRACT

Chitosan is one of the valuable products obtained from crustacean waste. The unique characteristics of chitosan (antimicrobial, antioxidant, anticancer, and anti-inflammatory) have increased its application in various sectors. Besides unique biological properties, chitosan or chitosan-based compounds can stabilize emulsions. Nevertheless, studies have shown that chitosan cannot be used as an efficient stabilizer because of its high hydrophilicity. Hence, this review aims to provide an overview of recent studies dealing with improving the emulsifying properties of chitosan. In general, two different approaches have been reported to improve the emulsifying properties of chitosan. The first approach tries to improve the stabilization property of chitosan by modifying its structure. The second one uses compounds such as polysaccharides, proteins, surfactants, essential oils, and polyphenols with more wettability and emulsifying properties than chitosan's particles in combination with chitosan to create complex particles. The tendency to use chitosan-based particles to stabilize Pickering emulsions has recently increased. For this reason, more studies have been conducted in recent years to improve the stabilizing properties of chitosan-based particles, especially using the electrostatic interaction method. In the electrostatic interaction method, numerous research has been conducted on using proteins and polysaccharides to increase the stabilizing property of chitosan.


Subject(s)
Chitosan , Chitosan/chemistry , Emulsions/chemistry , Surface-Active Agents/chemistry , Polysaccharides , Wettability , Particle Size , Emulsifying Agents
4.
Int J Biol Macromol ; 236: 123954, 2023 May 01.
Article in English | MEDLINE | ID: mdl-36898453

ABSTRACT

Large amounts of agricultural waste, especially marine product waste, are produced annually. These wastes can be used to produce compounds with high-added value. Chitosan is one such valuable product that can be obtained from crustacean wastes. Various biological activities of chitosan and its derivatives, especially antimicrobial, antioxidant, and anticancer properties, have been confirmed by many studies. The unique characteristics of chitosan, especially chitosan nanocarriers, have led to the expansion of using chitosan in various sectors, especially in biomedical sciences and food industries. On the other hand, essential oils, known as volatile and aromatic compounds of plants, have attracted the attention of researchers in recent years. Like chitosan, essential oils have various biological activities, including antimicrobial, antioxidant, and anticancer. In recent years, one of the ways to improve the biological properties of chitosan is to use essential oils encapsulated in chitosan nanocarriers. Among the various biological activities of chitosan nanocarriers containing essential oils, most studies conducted in recent years have been in the field of antimicrobial activity. It was documented that the antimicrobial activity was increased by reducing the size of chitosan particles in the nanoscale. In addition, the antimicrobial activity was intensified when essential oils were in the structure of chitosan nanoparticles. Essential oils can increase the antimicrobial activity of chitosan nanoparticles with synergistic effects. Using essential oils in the structure of chitosan nanocarriers can also improve the other biological properties (antioxidant and anticancer activities) of chitosan and increase the application fields of chitosan. Of course, using essential oils in chitosan nanocarriers for commercial use requires more studies, including stability during storage and effectiveness in real environments. This review aims to overview recent studies on the biological effects of essential oils encapsulated in chitosan nanocarriers, with notes on their biological mechanisms.


Subject(s)
Anti-Infective Agents , Chitosan , Oils, Volatile , Oils, Volatile/pharmacology , Oils, Volatile/chemistry , Antioxidants/pharmacology , Antioxidants/chemistry , Chitosan/chemistry , Anti-Infective Agents/pharmacology , Anti-Infective Agents/chemistry
5.
Trends Biotechnol ; 41(6): 785-797, 2023 06.
Article in English | MEDLINE | ID: mdl-36535818

ABSTRACT

Chitosan, an amino polysaccharide mostly derived from crustaceans, has been recently highlighted for its biological activities that depend on its molecular weight (MW), degree of deacetylation (DD), and acetylation pattern (AP). More importantly, for some advanced biomaterials, the homogeneity of the chitosan structure is an important factor in determining its biological activity. Here we review emerging enzymes and cell factories, respectively, for in vitro and in vivo preparation of chitosan oligosaccharides (COSs), focusing on advances in the analysis of the AP and structural modification of chitosan to tune its functions. By 'mapping' current knowledge on chitosan's in vitro and in vivo activity with its MW and AP, this work could pave the way for future studies in the field.


Subject(s)
Chitosan , Chitosan/chemistry , Biocompatible Materials/chemistry
6.
Int J Biol Macromol ; 207: 324-332, 2022 May 15.
Article in English | MEDLINE | ID: mdl-35259435

ABSTRACT

The recently developed technologies for immobilization of cellulase may address the challenges in costly hydrolysis of cellulose for cellulosic butanol production. In this study, a "hybrid" hydrolysis was developed based on chemical hydrolysis of cellulose to its oligomers followed by enzymatic post-hydrolysis of the resulting "soluble oligomers" by cellulase immobilized on chitosan-coated Fe3O4 nanoparticles. This hybrid hydrolysis stage was utilized in the process of biobutanol production from a waste textile, jeans waste, leading to selective formation of glucose and high yield of butanol production by Clostridium acetobutylicum. After validating the immobilization process, the optimum immobilization parameters including enzyme concentration and time were achieved on 8 h and 15.0 mg/mL, respectively. The reusability of immobilized enzyme showed that immobilized cellulase could retain 51.5% of its initial activity after three times reuses. Dilute acid hydrolysis of regenerated cellulose at 120-180 °C for 60 min 0.5-1.0% phosphoric acid led to less than 10 g/L glucose production, and enzymatic post-hydrolysis of the oligomers resulted in up to 51.5 g/L glucose. Fermentation of the hydrolysate was accompanied by 5.3 g/L acetone-butanol-ethanol (ABE) production. The simultaneous co-saccharification and fermentation (SCSF) of soluble and insoluble oligomers of cellulose led to 17.4 g/L ABE production.


Subject(s)
Cellulase , Chitosan , Clostridium acetobutylicum , Magnetite Nanoparticles , 1-Butanol , Acetone , Butanols , Cellulase/metabolism , Cellulose/metabolism , Clostridium acetobutylicum/metabolism , Ethanol , Fermentation , Glucose , Hydrolysis , Textiles
7.
Nat Food ; 3(10): 822-828, 2022 10.
Article in English | MEDLINE | ID: mdl-37117878

ABSTRACT

Crustacean waste, consisting of shells and other inedible fractions, represents an underutilized source of chitin. Here, we explore developments in the field of crustacean-waste-derived chitin and chitosan extraction and utilization, evaluating emerging food systems and biotechnological applications associated with this globally abundant waste stream. We consider how improving the efficiency and selectivity of chitin separation from wastes, redesigning its chemical structure to improve biotechnology-derived chitosan, converting it into value-added chemicals, and developing new applications for chitin (such as the fabrication of advanced nanomaterials used in fully biobased electric devices) can contribute towards the United Nations Sustainable Development Goals. Finally, we consider how gaps in the research could be filled and future opportunities could be developed to make optimal use of this important waste stream for food systems and beyond.

8.
PLoS One ; 16(7): e0253906, 2021.
Article in English | MEDLINE | ID: mdl-34292960

ABSTRACT

BACKGROUND: In addition to their educational role, resilient schools have a good capacity in response to disasters. Due to the large student population, the schools can be a safe and secure environment during disasters, in addition to maintaining their performance after. Given the role and importance of the schools, the impact of culture and environment on resilience, without any indigenous and comprehensive tool for measuring the resilience in Iran, the study aimed to design and psychometrically evaluate the measurement tools. METHOD: This study was conducted using a mixed-method sequential explanatory approach. The research was conducted in two main phases of production on items based on hybrid model and the psychometric evaluation of the tool. The second phase included validity (formal, content and construction) and reliability (multiplex internal similarity, consistency and reliability). RESULT: The integration of systematic and qualitative steps resulted in entering 91 items into the pool of items. After formal and content validity, 73 items remained and 44 were omitted in exploratory factor analysis. A questionnaire with 5 factors explained 52.08% of total variance. Finally, after the confirmatory factor analysis, the questionnaire was extracted with 29 questions and 5 factors including "functional", "architectural", "equipment", "education" and "safety". Internal similarity and stability in all factors were evaluated as good. CONCLUSION: The result showed that the 29-item questionnaire of school resilience in emergencies and disasters is valid and reliable, that can be used to evaluate school resilience. On the other hand, the questionnaire on assessment of school resilience in disasters enables intervention to improve its capacity.


Subject(s)
Disasters , Emergencies/psychology , Psychometrics , Schools , Students/psychology , Surveys and Questionnaires , Adult , Female , Humans , Male
9.
Front Bioeng Biotechnol ; 9: 794304, 2021.
Article in English | MEDLINE | ID: mdl-34976981

ABSTRACT

The bioconversion of lignocellulose into monosaccharides is critical for ensuring the continual manufacturing of biofuels and value-added bioproducts. Enzymatic degradation, which has a high yield, low energy consumption, and enhanced selectivity, could be the most efficient and environmentally friendly technique for converting complex lignocellulose polymers to fermentable monosaccharides, and it is expected to make cellulases and xylanases the most demanded industrial enzymes. The widespread nature of thermophilic microorganisms allows them to proliferate on a variety of substrates and release substantial quantities of cellulases and xylanases, which makes them a great source of thermostable enzymes. The most significant breakthrough of lignocellulolytic enzymes lies in lignocellulose-deconstruction by enzymatic depolymerization of holocellulose into simple monosaccharides. However, commercially valuable thermostable cellulases and xylanases are challenging to produce in high enough quantities. Thus, the present review aims at giving an overview of the most recent thermostable cellulases and xylanases isolated from thermophilic and hyperthermophilic microbes. The emphasis is on recent advancements in manufacturing these enzymes in other mesophilic host and enhancement of catalytic activity as well as thermostability of thermophilic cellulases and xylanases, using genetic engineering as a promising and efficient technology for its economic production. Additionally, the biotechnological applications of thermostable cellulases and xylanases of thermophiles were also discussed.

10.
Waste Manag ; 118: 45-54, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32889233

ABSTRACT

Co-processing of lignocellulosic wastes, e.g., garden and paper wastes, and the organic matters fraction of municipal solid waste (OMSW) in an integrated bioprocess is a possible approach to realize the potential of wastes for biobutanol production. Dilute acid pretreatment is a multi-functional stage for breaking the recalcitrant lignocellulose's structure, hydrolyzing hemicellulose, and hydrolyzing/solubilizing starch, leading to a pretreated solid and a rich hydrolysate. In this study, dilute-acid pretreatment of the combination of wastepaper and OMSW, composite I, as well as garden waste and OMSW, composite II, at severe conditions resulted in "pretreatment hydrolysates" containing 33.7 and 19.4 g/L sugar along with 18.9 and 33.2 g/L soluble starch, respectively. In addition, the hydrolysis of solid remained after the pretreatment of composite I and II resulted in "enzymatic hydrolysates" comprising 19.4 and 33 g/L sugar, respectively. The fermentation of the pretreatment hydrolysates and enzymatic hydrolysates resulted in 3.5 and 6.4 g/L ABE from composite I and 15 and 5.2 g/L ABE from composite II, respectively. In this process, 148 and 173 g ABE (60 and 100 g gasoline equivalent/kg) was obtained from each kg composite I and composite II, respectively, where co-processing of OMSW with lignocellulosic wastes resulted in 10 and 49% higher ABE than that produced from the individual substrates.


Subject(s)
Butanols , Solid Waste , Fermentation , Hydrolysis , Lignin/metabolism
11.
Adv J Emerg Med ; 4(2): e23, 2020.
Article in English | MEDLINE | ID: mdl-32322791

ABSTRACT

INTRODUCTION: Resilient schools can warranty students' health and survival at disasters. It is obligatory that schools be prepared for natural challenges through local programs. Considering the great population of students, disaster-resilient schools can be a safe and suitable environment for students at the time of disaster. OBJECTIVE: This study aims to identify certain operational strategies for establishing schools resilient to natural disasters. METHOD: This qualitative study was based on conventional content analysis. Using purposive sampling method, 24 experts in the fields of health in disasters, construction engineering, psychology, teaching, and administrative management participated in the study. Maximum variation sampling continued until data saturation was achieved. The data collected via unstructured interviews were analyzed with Graneheim and Lundmen's conventional content analysis. RESULTS: Content analysis resulted in four main categories as operational strategies for establishing disaster-resilient schools including: 1) "construction and non-construction optimization", with four subcategories of construct risk management, optimization of construct architecture and physical structure, correct construct localization, and promotion of non-construct safety, 2) "promotion of organizational coordination and interactions" with two subcategories, namely improvement in intra-organizational communication and improvement in extra-organizational communication, 3) "improvement in education" with three subcategories of holding educational courses for families and students, holding educational courses for managers and personnel, and holding simulated exercises, and 4) "process promotion" with four subcategories of increased preparedness, correct planning, creation of organizational structure, and rehabilitation facilitation. CONCLUSION: Various factors affecting schools' response to disasters form operational strategies to establish disaster-resilient schools. These strategies influence pre- and post-disaster preparedness. Awareness of these components followed by preparedness prior to disasters can save students' lives, improve school performance after disasters, and aid in establishing disaster-resilient schools as safe lodgings.

12.
J Educ Health Promot ; 9: 15, 2020.
Article in English | MEDLINE | ID: mdl-32154310

ABSTRACT

BACKGROUND AND OBJECTIVES: School resilience is defined as risk-reducing strategies used to create a safe environment for students when faced natural disasters. Resilient schools, in addition to their educational role, provide a suitable capacity for responding to disasters and rehabilitation after the incidence. This study determined the level of disaster resilience of schools in Yazd, central Iran. MATERIALS AND METHODS: This is a descriptive-analytic study conducted among 400 schools and 367 participants in Yazd, 2018. To collect data, we used the school resilience in disasters questionnaire (α =0.95 and intraclass correlation coefficient = 0.97 [95% confidence interval: 0.96-0.98]) containing 48 questions. We also analyzed the gleaned data through the Pearson correlation coefficient, one-way ANOVA, and independent t-test. RESULTS: The total score of school disaster resilience was 153.30 ± 29.57. In these schools, the function had the highest (47.76 ± 13.96), and safety had the lowest (6.74 ± 3.18) score among all areas of school disaster resilience. There was a positive significant correlation between total resilience and areas of function, education, structural, nonstructural, architecture, commute routes, safety, location, and equipment (P < 0.001). Location had the smallest (r = 0.424) and function had the greatest (r = 0.854) correlation with total resilience. CONCLUSION: It can help the school management board in assessing the level of resilience of their school and determining the priorities for disaster risk reduction. Awareness of the status of resilience can help policy-makers and experts create an effective program for increasing resilience.

13.
Anesth Pain Med ; 10(5): e100718, 2020 Oct.
Article in English | MEDLINE | ID: mdl-34150558

ABSTRACT

BACKGROUND: Postoperative pain management can improve patients' quality of life and decrease hospitalization rates. Preemptive analgesia may provide an effective approach for both pain control and opioid consumption decrease. A common approach for pain management after surgery is to relieve the pain that has already occurred. OBJECTIVES: The aim of this clinical trial was to compare the preemptive analgesic effect of single-dose versus two-dose administration of pregabalin, acetaminophen, naproxen, and dextromethorphan (PAND) combination. METHODS: This study involved 60 patients who had undergone one surgery (including nephrectomy, cystectomy, prostatectomy, colectomy, Whipple, and RPLND). They were randomly divided into two groups: The first group received a single dose of PAND, while the other group received a second dose within 6 hours after discharge from recovery. Pain intensity was assessed by the Universal Pain Assessment Tool (UPAT) in both groups 2, 4, 6, 8, 12, 24, and 48 hours postoperatively. The postoperative morphine dose in both groups was also recorded. Data were analyzed using SPSS version 25. RESULTS: Mean pain scores were significantly different between the two groups at 2, 12, 24, and 48 hours after surgery (P < 0.05). There was a statistically significant difference between the two groups in terms of opioid consumption (P < 0.001). The total opioid consumption in the second group (with the second administration of PAND) was lower than the first group. CONCLUSIONS: Preemptive analgesia with a second dose of PAND is an effective method for reducing pain and morphine consumption after surgery.

14.
Biotechnol Bioeng ; 117(2): 392-405, 2020 02.
Article in English | MEDLINE | ID: mdl-31709516

ABSTRACT

Clostridium acetobutylicum is widely used for the microbial production of butanol in a process known as acetone-butanol-ethanol (ABE) fermentation. However, this process suffers from several disadvantages including high oxygen sensitivity of the bacterium which makes the process complicated and necessitate oxygen elimination in the culture medium. Nesterenkonia sp. strain F has attracted interests as the only known non-Clostridia microorganism with inherent capability of butanol production even in the presence of oxygen. This bacterium is not delimited by oxygen sensitivity, a challenge in butanol biosynthesis, but the butanol titer was far below Clostridia. In this study, Nesterenkonia sp. strain F was cocultivated with C. acetobutylicum to form a powerful "coculture" for butanol production thereby eliminating the need for oxygen removal before fermentation. The response surface method was used for obtaining optimal inoculation amount/time and media formulation. The highest yield, 0.31 g/g ABE (13.6 g/L butanol), was obtained by a coculture initiated with 1.5 mg/L Nesterenkonia sp. strain F and inoculated with 15 mg/L C. acetobutylicum after 1.5 hr in a medium containing 67 g/L glucose, 2.2 g/L yeast extract, 4 g/L peptone, and 1.4% (vol/vol) P2 solution. After butanol toxicity assessment, where Nesterenkonia sp. strain F showed no butanol toxicity, the coculture was implemented in a 2 L fermenter with continual aeration leading to 20 g/L ABE.


Subject(s)
Butanols/metabolism , Clostridium acetobutylicum/metabolism , Coculture Techniques/methods , Micrococcaceae/metabolism , Aerobiosis , Bioreactors/microbiology
15.
Iran J Pharm Res ; 18(1): 496-505, 2019.
Article in English | MEDLINE | ID: mdl-31089384

ABSTRACT

The role of non-alcoholic fatty liver disease (NAFLD) as a potential independent cardiovascular disease (CVD) risk factor has recently gained considerable attention because CVD is the common cause of death in NAFLD patients. We aimed to estimate the effects of vitamin D supplementation alone or in combination with calcium on atherogenic indices, liver function tests, and grade of disease in patients with NAFLD. One-hundred twenty NAFLD patients were randomized in a double-blind, placebo-controlled clinical trial as follows: D (1000 IU vitamin D), CaD (500 mg as calcium carbonate plus 1000 IU vitamin D) or P (placebo), once daily with meals over 12 weeks. Adjusted for all the baseline measures, reduction in serum ALT, AST, LDL-C/HDL-C, TC/HDL-C, and non-HDL-C were significantly higher in the CaD compared with the P group (p < 0.001, p = 0.03, p < 0.001, p < 0.001, p < 0.001 and p < 0.001, respectively). Also, mean difference of serum ALT, LDL-C/HDL-C, TC/HDL-C, and TG/HDL-C were significantly higher in the CaD than D group (p < 0.001, p = 0.006, p < 0.001 and p = 0.03, respectively). Serum non-HDL-C was marginally decreased in the CaD compared with the D group (p = 0.06). With considering the BMI changes as covariate, reduction in the grade of fatty liver was significantly higher in the CaD and D groups than the P (p < 0.001). The present study suggests that supplemental calcium combined with vitamin D, but not vitamin D alone, may reduce serum atherogenic indices, liver function tests, and grade of disease in patients with NAFLD.

16.
Bioresour Technol ; 270: 236-244, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30219575

ABSTRACT

Municipal solid waste (MSW) was used as a source for biobutanol production via acetone, butanol, and ethanol (ABE) fermentation. Organosolv pretreatment was used for simultaneous extraction of inhibitors, particularly tannins, and pretreatment of lignocellulosic fraction prior to hydrolysis. The hydrolysates of the pretreated MSW contained appreciable amounts of sugars and soluble starch together with a tolerable amount of inhibitors for Clostridium acetobutylicum. The hydrolysate obtained from MSW pretreated with 85% ethanol at 120 °C for 30 min fermented to the highest ABE concentration of 13.06 g/L with the yield of 0.33 g/g carbon source. Through this process, 102.4 mg butanol, 40.16 mg acetone, and 13.14 mg ethanol were produced from each g of organic fraction of MSW (OFMSW). The pretreatment at mild conditions with higher ethanol concentration accompanied with the lowest glucose yield (0.145 g/g) and the highest starch recovery resulted in the uppermost ABE yield of 0.16 g/g OFMSW.


Subject(s)
Butanols/metabolism , Solid Waste , Acetone/metabolism , Bioreactors , Clostridium acetobutylicum , Ethanol/metabolism , Fermentation , Hydrolysis , Inactivation, Metabolic
17.
Bioresour Technol ; 270: 702-721, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30195696

ABSTRACT

Butanol is acknowledged as a drop-in biofuel that can be used in the existing transportation infrastructure, addressing the needs for sustainable liquid fuel. However, before becoming a thoughtful alternative for fossil fuel, butanol should be produced efficiently from a widely-available, renewable, and cost-effective source. In this regard, lignocellulosic materials, the main component of organic wastes from agriculture, forestry, municipalities, and even industries seems to be the most promising source. The butanol-producing bacteria, i.e., Clostridia sp., can uptake a wide range of hexoses, pentoses, and oligomers obtained from hydrolysis of cellulose and hemicellulose content of lignocelluloses. The present work is dedicated to reviewing different processes containing pretreatment and hydrolysis of hemicellulose and cellulose developed for preparing fermentable hydrolysates for biobutanol production.


Subject(s)
1-Butanol/metabolism , Lignin/metabolism , Biofuels , Cellulose/metabolism , Fermentation , Hydrolysis , Lignin/chemistry
18.
Iran J Med Sci ; 43(1): 26-31, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29398749

ABSTRACT

BACKGROUND: Studies have shown that zinc and selenium deficiency is common in nonalcoholic fatty liver disease (NAFLD). However, the effects of zinc and selenium co-supplementation before and/or after disease progression on NAFLD are not clear enough. The aim of this study was to compare the effects of zinc and selenium co-supplementation before and/or after disease progression on NAFLD prognosis. MATERIALS AND METHODS: Forty male Sprague-Dawley rats (197±4 g) were randomly assigned to 4 dietary groups: normal-fat diet (NFD; receiving 9% of calories as fat), high-fat diet (HFD; receiving 82% of calories as fat), supplementation before disease progression (S+HFD), and supplementation after disease progression (HFD+S). The diets were implemented over a 20-week period in all the groups. Biochemical and histologic parameters were compared between the 4 groups, and between-group comparisons were also carried out. RESULTS: There were significant differences in the average food dietary intake (P<0.001), weight (P<0.001), fasting blood sugar (P=0.005), triglyceride (P<0.001), total cholesterol (P<0.001), low-density lipoprotein cholesterol (P=0.002), high-density lipoprotein cholesterol (P=0.001), alanine aminotransferase (P<0.001), and aspartate aminotransferase (P<0.001) between the 4 dietary groups. Serum triglyceride and total cholesterol were significantly lower in the HFD+S Group than in the S+HFD Group (P<0.001 and P=0.003, respectively). Fat accumulation was significantly reduced in the HFD+S Group (P<0.001). CONCLUSION: Zinc and selenium co-supplementation after disease progression improved biochemical and histologic parameters in an experimental model of NAFLD.

19.
Biol Trace Elem Res ; 181(2): 288-295, 2018 Feb.
Article in English | MEDLINE | ID: mdl-28577233

ABSTRACT

Studies have shown that non-alcoholic fatty liver disease (NAFLD) patients are more prone to cardiovascular disease (CVD). Zinc and selenium deficiency are common in NAFLD. But the effects of zinc and selenium co-supplementation before and/or after disease progression on CVD markers are not clear in NAFLD patients. This study aimed to compare the effects of zinc and selenium co-supplementation before and/or after disease progression on some of the CVD markers in an experimental model of NAFLD. Forty male Sprague Dawley rats (197 ± 4 g) were randomly assigned into four dietary groups: control group (C; received 9% of calorie as fat), model group (M; received 82% of calorie as fat), and supplementation before (BS) or after (AS) disease progression. Animals were fed diets for 20 weeks in all groups. Fasting plasma glucose (FPG), insulin, HOMA-IR, ALT, AST, lipid profile, malondialdehyde (MDA) and vascular endothelial growth factor (VEGF) levels were measured as CVD indices. Serum ALT, AST, FPG, insulin, MDA, VEGF and HOMA-IR were significantly higher in the M than C group. Co-supplementation reduced serum ALT and AST levels in the BS and AS groups compared with the M group. FPG, insulin, HOMA-IR, VEGF, MDA, LDL/HDL-c and TC/HDL-c ratio were significantly reduced in the AS compared with the M group. TG/HDL-c ratio was significantly reduced in the BS and AS compared with the M group. Serum MDA, VEGF, Insulin and HOMA-IR were significantly lowered in the AS than BS group (p < 0.05). Zinc and selenium co-supplementation after NAFLD progression reduced CVD risk indices in an experimental model.


Subject(s)
Biomarkers/metabolism , Disease Models, Animal , Lipid Peroxidation/drug effects , Neovascularization, Pathologic/drug therapy , Non-alcoholic Fatty Liver Disease/drug therapy , Selenium/pharmacology , Zinc/pharmacology , Animals , Cardiovascular Diseases/prevention & control , Diet, High-Fat , Dietary Supplements , Male , Rats , Rats, Sprague-Dawley , Selenium/administration & dosage , Zinc/administration & dosage
20.
Clin Nutr ; 36(6): 1490-1497, 2017 12.
Article in English | MEDLINE | ID: mdl-27720403

ABSTRACT

BACKGROUND & AIMS: Despite evidence for beneficial effects of vitamin D, to our knowledge, no study has compared the effects of calcium supplementation with vitamin D on non-alcoholic fatty liver disease (NAFLD) regression during a hypo-energetic program. We compared the effect of the vitamin D supplementation with and without calcium on anthropometric measures and biochemical parameters in NAFLD patients during a weight-loss program. METHODS: A 12-week, randomized, controlled, double-blind trial was conducted in 120 NAFLD patients randomly assigned to receive 25 µg calcitriol (n = 37), 500 mg calcium carbonate + 25 µg calcitriol (n = 37), or placebo (n = 36) every day with their lunch meals while following a weight-loss program. RESULTS: Weight, BMI and fat mass reduction were significant in each group after 12 wk of intervention (p < 0.001), but differences among the groups was not significant after 12 wk of the study, adjusted to the baseline measurements. Significant reduction in fasting plasma glucose (FPG), insulin, insulin resistance (by HOMA-IR) and TG concentrations and an increase in HDL.C was seen over the 12 wk of study in each group (p < 0.001). Adjusting to the baseline measurements, there was significant difference in FPG (p < 0.001), HOMA-IR (p < 0.001), serum insulin (p = 0.01), TG (p = 0.01) and HDL.C (p < 0.001) among the groups after 12 wk of the study. The calcium plus calcitriol group showed a significant decrease in ALT and FPG and increase in HDL.C level compared with the calcitriol group, adjusted to the baseline measures (p < 0.001). CONCLUSIONS: Our results suggest that calcium plus calcitriol supplementation for 12 weeks may be potentially effective for biochemical parameters in NAFLD patients. Further additional larger controlled trials are needed to confirm these findings. REGISTRATION: Registered under ClinicalTrials.gov Identifier no. IRCT201408312709N29.


Subject(s)
Calcitriol/administration & dosage , Calcitriol/blood , Calcium/administration & dosage , Non-alcoholic Fatty Liver Disease/blood , Non-alcoholic Fatty Liver Disease/therapy , Adolescent , Adult , Aged , Blood Glucose/metabolism , Body Mass Index , Calcium/blood , Cholesterol/blood , Diet , Dietary Supplements , Double-Blind Method , Exercise , Female , Humans , Insulin/blood , Male , Middle Aged , Sample Size , Sunlight , Triglycerides/blood , Vitamin D/blood , Weight Reduction Programs , Young Adult
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