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1.
Molecules ; 28(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36985611

RESUMO

2,3,5,6-Tetramethylpyrazine (TTMP) is an active ingredient of Ligusticum wallichii Franch. It can be used in medicine and food fields. In this study, Bacillus sp. TTMP20 was applied to produce TTMP using cane molasses as a carbon source. After pretreatment with phosphoric acid, 170 mL/L treated molasses, combined with 10 g/L yeast powder, 30 g/L tryptone and 30 g/L (NH4)2HPO4 were used for fermentation. After 36 h, TTMP output reached the highest value of 208.8 mg/L. The yield of TTMP using phosphoric acid-treated molasses as carbon source was 145.59% higher than control. Under the sulfuric acid treatment process of molasses (150 g), the maximum yield of TTMP was 895.13 mg/L, which was 183.18% higher than that of untreated molasses (316.1 mg/L). This study demonstrated that molasses is a high-quality and inexpensive carbon source for the manufacture of TTMP, laying the groundwork for the future industrial production of TTMP.


Assuntos
Bacillus , Melaço , Bengala , Fermentação , Carbono , Saccharomyces cerevisiae
2.
Molecules ; 28(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37687063

RESUMO

As a biodegradable and renewable material, polylactic acid is considered a major environmentally friendly alternative to petrochemical plastics. Microbial fermentation is the traditional method for lactic acid production, but it is still too expensive to compete with the petrochemical industry. Agro-industrial wastes are generated from the food and agricultural industries and agricultural practices. The utilization of agro-industrial wastes is an important way to reduce costs, save energy and achieve sustainable development. The present study aimed to develop a method for the valorization of Zizania latifolia waste and cane molasses as carbon sources for L-lactic acid fermentation using Rhizopus oryzae LA-UN-1. The results showed that xylose derived from the acid hydrolysis of Z. latifolia waste was beneficial for cell growth, while glucose from the acid hydrolysis of Z. latifolia waste and mixed sugars (glucose and fructose) from the acid hydrolysis of cane molasses were suitable for the accumulation of lactic acid. Thus, a three-stage carbon source utilization strategy was developed, which markedly improved lactic acid production and productivity, respectively reaching 129.47 g/L and 1.51 g/L·h after 86 h of fermentation. This work demonstrates that inexpensive Z. latifolia waste and cane molasses can be suitable carbon sources for lactic acid production, offering an efficient utilization strategy for agro-industrial wastes.


Assuntos
Melaço , Rhizopus oryzae , Bengala , Resíduos Industriais , Ácido Láctico , Carbono , Glucose
3.
Microb Cell Fact ; 21(1): 140, 2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842664

RESUMO

BACKGROUND: Poly-γ-glutamic acid (γ-PGA) is a biopolymer and has various applications based on its biocompatibility, non-toxicity, and edibility. Low-molecular-weight (Mw)-γ-PGA has promising applications in agriculture and pharmaceuticals. It is traditionally produced by enzymatic hydrolysis. Cost-effective bioproduction of low-Mw-γ-PGA is essential for commercial application of γ-PGA. RESULTS: Bacillus subtilis 242 is a newly isolated low-Mw-γ-PGA-producing strain. To develop cost-effective production of γ-PGA using this newly isolated strain, cane molasses and corn steep liquor were used to produce γ-PGA. The concentration of cane molasses was optimized and 100 g/L cane molasses resulted in high γ-PGA production. The effects of yeast extract and corn steep liquor on γ-PGA yield were investigated. High concentration of γ-PGA was obtained in the medium with corn steep liquor. A concentration of 32.14 g/L γ-PGA was achieved in fed-batch fermentation, with a productivity of 0.67 g/L/h and a percentage yield (gγ-PGA/gglutamate) of 106.39%. The Mw of γ-PGA was 27.99 kDa. CONCLUSION: This study demonstrated the potential application of B. subtilis 242 for cost-effective production of low-Mw-γ-PGA from cane molasses.


Assuntos
Bacillus subtilis , Melaço , Corantes , Fermentação , Ácido Glutâmico , Ácido Poliglutâmico/análogos & derivados
4.
Molecules ; 27(3)2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35164219

RESUMO

Firstly, 2,3-butanediol (2,3-BDO) is a chemical platform used in several applications. However, the pathogenic nature of its producers and the expensive feedstocks used limit its scale production. In this study, cane molasses was used for 2,3-BDO production by a nonpathogenic Clostridium ljungdahlii. It was found that cane molasses alone, without the addition of other ingredients, was favorable for use as the culture medium for 2,3-BDO production. Compared with the control (i.e., the modified DSMZ 879 medium), the differential genes are mainly involved in the pathways of carbohydrate metabolism, membrane transport, and amino acid metabolism in the case of the cane molasses alone. However, when cane molasses alone was used, cell growth was significantly inhibited by KCl in cane molasses. Similarly, a high concentration of sugars (i.e., above 35 g/L) can inhibit cell growth and 2,3-BDO production. More seriously, 2,3-BDO production was inhibited by itself. As a result, cane molasses alone with an initial 35 g/L total sugars was suitable for 2,3-BDO production in batch culture. Finally, an integrated fermentation and membrane separation process was developed to maintain high 2,3-BDO productivity of 0.46 g·L-1·h-1. Meanwhile, the varied fouling mechanism indicated that the fermentation properties changed significantly, especially for the cell properties. Therefore, the integrated fermentation and membrane separation process was favorable for 2,3-BDO production by C. ljungdahlii using cane molasses.


Assuntos
Reatores Biológicos , Butileno Glicóis/metabolismo , Clostridium/metabolismo , Fermentação , Membranas/metabolismo , Melaço/análise , Técnicas de Cultura Celular por Lotes , Butileno Glicóis/química , Clostridium/crescimento & desenvolvimento , Membranas/química
5.
Biotechnol Bioeng ; 116(4): 745-756, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30597517

RESUMO

D-Allulose 3-epimerase (DAE) has been applied to produce D-allulose, a low-calorie and functional sweetener. In this study, a new DAE from Paenibacillus senegalensis was characterized in Escherichia coli. Furthermore, we presented a tandem isoenzyme gene expression strategy to express multiple DAEs in one cell and construct food-grade expression systems based on Corynebacterium glutamicum. Seventeen expression cassettes based on three DAE genes from different organisms were constructed. Among all recombinant strains, DAE16 harboring three DAE genes in an expression vector exhibited the highest enzyme activity with 22.7 U/mg. Whole-cell transformation of DAE16 produced 225 g/L D-allulose with a volumetric productivity of 353 g·g -1 ·hr -1 . The catalytic efficiency of strain C-DAE9 integrating total 11 DAE genes in chromosome was 16.4-fold higher than strains carrying one DAE. Fed-batch culture of C-DAE9 gave enzyme activity of 44,700 U/L. We also expressed a thermostable invertase in C. glutamicum and obtained enzyme activity of 29 U/mg. Immobilized cells expressing DAE or invertase exhibited 80% of retained activity after 30 cycles of catalytic reactions. Those immobilized cells were coupled to produce 61.2 g/L D-allulose from cane molasses in a two-step reaction process. This study provided an efficient approach for enzyme preparation and allowed access to produce D-allulose from other abundant and low-cost feedstock enriched with sucrose.


Assuntos
Proteínas de Bactérias/genética , Corynebacterium glutamicum/genética , Escherichia coli/genética , Frutose/metabolismo , Paenibacillus/genética , Racemases e Epimerases/genética , Proteínas de Bactérias/metabolismo , Corynebacterium glutamicum/metabolismo , Escherichia coli/metabolismo , Frutose/análise , Expressão Gênica , Genes Bacterianos , Microbiologia Industrial , Isoenzimas/metabolismo , Melaço/análise , Paenibacillus/metabolismo , Filogenia , Racemases e Epimerases/metabolismo , Saccharum/química , Saccharum/metabolismo , Transformação Genética
6.
Molecules ; 24(7)2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30925836

RESUMO

: Cane molasses is one of the main by-products of sugar refineries, which is rich in sucrose. In this work, low-cost cane molasses was introduced as an alternative substrate for isomaltulose production. Using the engineered Yarrowia lipolytica, the isomaltulose production reached the highest (102.6 g L-¹) at flask level with pretreated cane molasses of 350 g L-¹ and corn steep liquor of 1.0 g L-¹. During fed-batch fermentation, the maximal isomaltulose concentration (161.2 g L-¹) was achieved with 0.96 g g-¹ yield within 80 h. Simultaneously, monosaccharides were completely depleted, harvesting the high isomaltulose purity (97.4%) and high lipid level (12.2 g L-¹). Additionally, the lipids comprised of 94.29% C16 and C18 fatty acids, were proved suitable for biodiesel production. Therefore, the bioprocess employed using cane molasses in this study was low-cost and eco-friendly for high-purity isomaltulose production, coupling with valuable lipids.


Assuntos
Técnicas de Cultura Celular por Lotes/métodos , Fermentação , Engenharia Genética/métodos , Isomaltose/análogos & derivados , Lipídeos/química , Melaço , Saccharum/química , Yarrowia/metabolismo , Biocombustíveis , Biotransformação/efeitos dos fármacos , Carbono/farmacologia , Ácidos Graxos/análise , Fermentação/efeitos dos fármacos , Isomaltose/isolamento & purificação , Lipídeos/biossíntese , Yarrowia/efeitos dos fármacos
7.
Food Technol Biotechnol ; 57(3): 388-398, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31866752

RESUMO

Carotenoids are natural pigments that can be produced through biotechnological processes. However, the costs are relatively high and can be minimized by using lower-cost substrates as alternative nutrient sources. The fed-batch fermentation is one of the techniques used to obtain a high biomass concentration and/or maximum production. Thus, the aim of this work is to produce carotenoids in batch and fed-batch fermentation with the yeast Rhodotorula mucilaginosa CCT 7688 using agroindustrial byproducts in the culture medium. Carotenoid production was increased using experimental designs, which modified the concentration of the agroindustrial medium. In batch production the highest concentrations of total carotenoids (1248.5 µg/L) and biomass (7.9 g/L) were obtained in the medium containing 70 g/L sugar cane molasses and 3.4 g/L corn steep liquor at 25 °C and 180 rpm in 168 h, demonstrating an increase of 17% when compared to the standard yeast malt medium (1200 µg/L). In the fed-batch production, different feeding strategies were tested with 30 g/L sugar cane molasses and 6.5 g/L corn steep liquor, reaching a total carotenoid production of 3726 µg/L and biomass concentration of 16 g/L. Therefore, the strategy of the fed-batch process resulted in an increase in the carotenoid production of approx. 400% compared to that in the batch process (740.3 µg/L). Thus, the R. mucilaginosa strain has the potential to produce carotenoids in agroindustrial medium.

8.
Bioprocess Biosyst Eng ; 41(8): 1121-1131, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29680868

RESUMO

The study investigated an integrated bioprocessing of raw and by-products from sugarcane and dairy industries for production of non-digestible prebiotic and functional ingredients. The low-priced feedstock, whey, molasses, table sugar, jaggery, etc., were subjected to transglucosylation reactions catalyzed by dextransucrase from Leuconostoc mesenteroides MTCC 10508. HPLC analysis approximated production of about 11-14 g L-1 trisaccharide i.e. 2-α-D-glucopyranosyl-lactose (4-galactosyl-kojibiose) from the feedstock prepared from table sugar, jaggery, cane molasses and liquid whey, containing about 30 g L-1 sucrose and lactose each. The trisaccharide was hydrolysed into the prebiotic disaccharide, kojibiose, by employing recombinant ß-galactosidase from Escherichia coli. The enzyme ß-galactosidase achieved about 90% conversion of 2-α-D-glucopyranosyl-lactose into kojibiose. The D-fructose generated by catalytic reactions of dextransucrase was targeted for catalytic transformation into rare sugar, D-allulose (or D-psicose), by treating the samples with Smt3-D-psicose 3-epimerase. The catalytic reactions resulted in the conversion of ~ 25% D-fructose to D-allulose. These bioactive compounds are known to exert a plethora of benefits to human health, and therefore, are preferred ingredients for making functional foods.


Assuntos
Metabolismo dos Carboidratos , Carboidratos , Indústria de Laticínios , Melaço/microbiologia , Saccharum/metabolismo
9.
J Sci Food Agric ; 97(1): 222-229, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26991843

RESUMO

BACKGROUND: The high cost of phytase production is the most limiting factor in its application in animal feeds. The present study aimed to develop a low-cost medium for production of a novel phytase in submerged fermentation using inexpensive agro-industrial by-products. The applicability of phytase in dephytinisation of commonly used food/feed ingredients, i.e. soybean meal and wheat bran, was also investigated. RESULTS: Using a one-factor-at-a-time approach, soybean meal and cane molasses were identified as significant agro-industrial by-products and these factors were subsequently optimised using response surface methodology (RSM). A central composite design was employed to further enhance phytase yield. Under optimum conditions of soybean meal 22.3 g L-1 , cane molasses 100 g L-1 and 39 h fermentation, phytase production increased to 56.562 U mL-1 , indicating more than 28-fold enhancement. The enzyme efficiently dephytinised wheat bran and soybean meal after 24 h incubation at 56.5 °C and increased inorganic phosphate content by 240% and 155%, respectively. CONCLUSION: Soybean meal and cane molasses were successfully used for enhancement of phytase production as economical carbon, nitrogen and phytic acid sources using RSM. The phytase showed a good capability to dephytinise wheat bran and soybean meal, demonstrating that the enzyme can be considered as a potential candidate for industrial food and feed applications. © 2016 Society of Chemical Industry.


Assuntos
6-Fitase/biossíntese , Ração Animal , Bacillus subtilis/enzimologia , Manipulação de Alimentos/métodos , Melaço , Agricultura , Bacillus subtilis/metabolismo , Fibras na Dieta/análise , Fermentação , Resíduos Industriais , Ácido Fítico/metabolismo , Glycine max/química
10.
Bioprocess Biosyst Eng ; 39(1): 181-91, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26581490

RESUMO

Economical production of xylanase and three cellulases, endo-ß-1,4-glucanase (CMCase), exo-ß-1,4-glucanase (FPase), ß-glucosidase (BGL) was studied in submerged fermentation using cane molasses medium. A statistical optimization approach involving Plackett-Burman design and response surface methodology (RSM) resulted in the production of 72,410, 36,420, 32,420 and 5180 U/l of xylanase, CMCase, FPase and ß-glucosidase, respectively. Optimization resulted in more than fourfold improvements in production of xylanolytic and cellulolytic enzymes. Scale up of enzymes production in shake flasks of varied volumes was sustainable, suggesting a good scope for large scale enzyme production. Addition of microparticles engineered fungal morphology and enhanced enzymes production. Xylanase of S. thermophile is a neutral xylanase displaying its optimal activity at 60 °C while all the cellulases are optimally active at pH 5.0 and 60 °C. The efficacy of enzyme cocktail in waste tea cup paper and rice straw hydrolysis showed that maximum sugar yield of 578.12 and 421.79 mg/g substrate for waste tea cup and rice straw, respectively, were achieved after 24 h. Therefore, concomitant production of cellulolytic and xylanolytic enzymes will be beneficial for the saccharification of lignocellulosics in generating both monomeric and oligomeric sugars for biofuels and other biotechnological applications.


Assuntos
Celulases/química , Endo-1,4-beta-Xilanases/química , Proteínas Fúngicas/química , Sporothrix/enzimologia , Celulases/biossíntese , Celulases/economia , Endo-1,4-beta-Xilanases/biossíntese , Endo-1,4-beta-Xilanases/economia , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/economia , Temperatura Alta , Concentração de Íons de Hidrogênio
11.
J Environ Manage ; 170: 28-36, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26789200

RESUMO

This study investigates the treatment of the distilleries vinasse using a hybrid process integrating ozone oxidation and granular activated carbons (GAC) in both batch and continuous operation mode. The batch-process studies have been carried out to optimize initial influent pH, GAC doses, the effect of the ozone (O3) and hydrogen peroxide (H2O2) concentrations on chemical oxygen demand (COD) and color removal of the distilleries vinasse. The continuous process was carried out on GAC and ozone treatment alone as well as the hybrid process comb both methods to investigate the synergism effectiveness of the two methods for distilleries vinasse COD reduction and color removal. In a continuous process, the Yan model described the experimental data better than the Thomas model. The efficiency of ozonation of the distilleries vinasse was more effective for color removal (74.4%) than COD removal (25%). O3/H2O2 process was not considerably more effective on COD and color removal. Moreover, O3/GAC process affected negatively on the removal efficiency by reducing COD and color from distilleries vinasse. The negative effect decreased by increasing pH value of the influent.


Assuntos
Carvão Vegetal/química , Corantes/química , Resíduos Industriais , Ozônio/química , Poluentes Químicos da Água/química , Humanos , Oxigênio/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
12.
Prep Biochem Biotechnol ; 46(8): 798-802, 2016 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26829650

RESUMO

Poly(L-malic acid) (PMA) is a natural polyester with many attractive properties for biomedical application. However, the cost of PMA production is high when glucose is used as a carbon source. To solve this problem, cane molasses as a low-cost feedstock was applied for the production of PMA. Six pretreatment methods were applied to cane molasses before fermentation. Pretreatment with combined tricalcium phosphate, potassium ferrocyanide, and sulfuric acid (TPFSA) removed significant amounts of metal ions from cane molasses. The PMA concentration increased from 5.4 g/L (untreated molasses) to 36.9 g/L (TPFSA-pretreated molasses) after fermentation in shake flasks. A fed-batch fermentation strategy was then developed. In this method, TPFSA-pretreated cane molasses solution was continuously fed into the fermentor to maintain the total sugar concentration at 20 g/L. This technique generated approximately 95.4 g/L PMA with a productivity of 0.57 g/L/hr. The present study indicated that fed-batch fermentation using pretreated cane molasses is a feasible technique for producing high amounts of PMA.


Assuntos
Ascomicetos/metabolismo , Fermentação , Microbiologia Industrial/métodos , Malatos/metabolismo , Polímeros/metabolismo , Saccharum/metabolismo
13.
J Food Sci Technol ; 52(6): 3571-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26028739

RESUMO

In the present work Lactobacillus delbrueckii was used to utilize agro-industrial byproduct (cane molasses) for lactic acid production under submerged fermentation process. Screening of LAB was done by Fourier transform infra red spectroscopy (FTIR). Effect of different amino acids (DL-Phenylalanine, L-Lysine and DL-Aspartic acid) on the fermentation process was done by high performance liquid chromatography (HPLC). Central composite rotatable design (CCRD) was used to optimize the levels of three parameters viz. tween 80, amino acid and cane molasses concentration during fermentative production of lactic acid. Under optimum condition lactic acid production was enhanced from 55.89 g/L to 84.50 g/L. Further, validation showed 81.50 g/L lactic acid production. Scale up was done on 7.5 L fermentor. Productivity was found to be 3.40 g/L/h which was higher than previous studies with reduced fermentation time from 24 h to 12 h. Further characterization of lactic acid was done by FTIR.

14.
Life (Basel) ; 14(6)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38929739

RESUMO

The production of citric acid, a vital agricultural commodity utilized across various industries such as food, beverages, pharmaceuticals, agriculture, detergents, and cosmetics, predominantly relies on microbial fermentation, with Aspergillus niger accounting for approximately 90% of global production. In this study, we aimed to optimize the key factors influencing citric acid production, with a focus on strains, fermentation techniques, and carbon sources, particularly sugarcane molasses. A. niger, sourced from the Botany department/Biotechnology laboratories at Govt. College of Science, Lahore, was employed for citric acid production. The process involved inoculum preparation through spore collection from 3 to 5 days of cultured PDA slants. The fermentation medium, comprising cane molasses with a 15% sugar concentration, was meticulously prepared and optimized for various factors, including magnesium sulfate, potassium ferrocyanide, time of addition of potassium ferrocyanide, ammonium oxalate, and calcium chloride. Our optimization results shed light on the significant impact of different factors on citric acid production. For instance, the addition of 0.4 g/L magnesium sulfate led to a maximum yield of 75%, while 2 g/L potassium ferrocyanide, added at 24 h, achieved a yield of 78%. Remarkably, ammonium oxalate, at a concentration of 10 g/L, resulted in a notable 77% yield. Conversely, the addition of calcium chloride exhibited negligible effects on citric acid production, with the control group yielding more at 78%. Our study underscores the potential for optimizing factors to enhance citric acid production by A. niger in submerged fermentation. These findings highlight the pivotal role of magnesium sulfate, potassium ferrocyanide, and ammonium oxalate in augmenting citric acid yields while emphasizing the minimal impact of calcium chloride. Ultimately, these insights contribute to advancing our understanding of microbial citric acid biosynthesis, providing valuable implications for industrial applications and future research endeavors.

15.
Biotechnol Genet Eng Rev ; : 1-23, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36951575

RESUMO

The current article emphasized on cultural conditions for Alcaligenes sp. NCIM 5085 to synthesize Polyhydroxybutyrate (PHB) from sugar industry waste during batch fermentation. Alcaligenes sp. NCIM 5085 was found to grow best in conditions that included 40 g l-1 of cane molasses, 1 g l-1 of ammonium sulphate, 10% inoculum with neutral pH and 48 h of incubation time. Sudan Black B staining was employed to verify the PHB synthesis initially, and further TEM analysis was performed to confirm it. The structural analysis of recovered PHB was carried out by using GC-MS, FTIR, 1H NMR and 13C NMR analysis. The absorption peak at 1724.56 cm-1 revealed the presence of C=O (carbonyl) group by FTIR, which is an indicator of PHB presence. Furthermore, results of NMR and GC-MS analysis confirmed the recovered polymer was PHB. The thermal properties of recovered polymer were analyzed by TGA, DTG and DSC and showed thermal stability of PHB. The observed glass transient temperature (Tg) -2.8°C was within the normal PHB range of Tg. However, melting temperature of recovered PHB was 161.7°C, where the degree of crystallinity was lower than standard PHB that widens the application possibilities.

16.
Biotechnol Biofuels Bioprod ; 16(1): 155, 2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37865803

RESUMO

BACKGROUND: Sucrose-rich sugarcane trash surpasses 28 million tons globally per year. Effective biorefinery systems could convert these biomasses to bioproducts, such as bioethanol from sugarcane sucrose in Brazil. Thermophilic microbes for biofuels have attracted great attention due to their higher fermentation temperature and wide substrate spectrum. However, few thermophiles using sucrose or molasses for biofuels production was reported. Thermoanaerobacterium aotearoense SCUT27 has been considered as an efficient ethanol producer, but it cannot directly utilize sucrose. In this study, various sucrose metabolic pathways were introduced and analyzed in Thermoanaerobaterium. RESULTS: The sucrose-6-phosphate hydrolase (scrB), which was from a screened strain Thermoanaerobacterium thermosaccharolyticum G3-1 was overexpressed in T. aotearoense SCUT27 and endowed this strain with the ability to utilize sucrose. In addition, overexpression of the sucrose-specific PTS system (scrA) from Clostridium acetobutylicum accelerated the sucrose transport. To strengthen the alcohols production and substrates metabolism, the redox-sensing transcriptional repressor (rex) in T. aotearoense was further knocked out. Moreover, with the gene arginine repressor (argR) deleted, the ethanologenic mutant P8S10 showed great inhibitors-tolerance and finally accumulated ~ 34 g/L ethanol (a yield of 0.39 g/g sugars) from pretreated cane molasses in 5 L tank by fed-batch fermentation. When introducing butanol synthetic pathway, 3.22 g/L butanol was produced by P8SB4 with a yield of 0.44 g alcohols/g sugars at 50℃. This study demonstrated the potential application of T. aotearoense SCUT27 for ethanol and butanol production from low cost cane molasses. CONCLUSIONS: Our work provided strategies for sucrose utilization in thermophiles and improved biofuels production as well as stress tolerances of T. aotearoense SCUT27, demonstrating the potential application of the strain for cost-effective biofuels production from sucrose-based feedstocks.

17.
Waste Manag ; 157: 47-59, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36525879

RESUMO

Metals recovery from spent lithium coin cells (SCCs) is enjoying great attention due to environmental problems and metal-rich contents such as Mn and Li. Fungi can generate many organic acids, and metals can be dissolved, but sucrose is not an economical medium. The main objective of this study is to find a suitable carbon substrate in place of sucrose for fungal bioleaching. We have developed an environmentally friendly, cost-effective, and green method for recycling and detoxifying Mn and Li from SCCs using the spent culture medium fromPenicillium citrinumcultivation. Sugar cane molasses and sucrose were selected as carbon sources. Based on the extracted fungal metabolites, the effects of pulp density, temperature, and leaching time were assessed on metal dissolution. The most suitable conditions were 30 g/L of pulp density, a temperature of 40 °C, and 4 days of leaching time in spent molasses medium, which led to a high extraction of 87% Mn and 100% Li. Based on EDX-mapping analyses, it was found that the initial concentration of ∑ (Mn + C) in the SCCs powder was almost 100% while reaching nearly 6.4% after bioleaching. After bioleaching, an analysis of residual powder confirmed that metal dissolution from SCCs was effective owing to fungal metabolites. The economic study showed that the bioleaching method is more valuable for the dissolution of metals than the chemical method; In addition to improving bioleaching efficiency, molasses carbon sources can be used for industrial purposes.


Assuntos
Fontes de Energia Elétrica , Lítio , Análise Custo-Benefício , Pós , Metais/química , Reciclagem/métodos
18.
Bioresour Technol ; 376: 128833, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36889604

RESUMO

Cane molasses (CM) is a sugar-rich agro-industrial byproduct. The purpose of this study is to synthesize docosahexaenoic acid (DHA) in Schizochytrium sp. by using CM. The single factor analysis showed that sucrose utilization was the main factor limiting the utilization of CM. Therefore, the endogenous sucrose hydrolase (SH) was overexpressed in Schizochytrium sp., which enhanced the sucrose utilization rate 2.57-fold compared to the wild type. Furthermore, adaptive laboratory evolution was used to further improve sucrose utilization from CM. Comparative proteomics and RT-qPCR were used out to analyze the metabolic differences of evolved strain grown on CM and glucose, respectively. Finally, a constant flow rate CM feeding strategy was implemented, whereby the DHA titer and lipid yield of the final strain OSH-end reached 25.26 g/L and 0.229 g/g sugar, respectively. This study demonstrated the CM is a cost-effective carbon source for industrial DHA fermentation.


Assuntos
Ácidos Docosa-Hexaenoicos , Estramenópilas , Melaço , Bengala , Fermentação , Glucose/metabolismo , Estramenópilas/genética , Estramenópilas/metabolismo
19.
Appl Biochem Biotechnol ; 195(5): 3406-3424, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36598641

RESUMO

Cane molasses is a by-product of sugar industry. It is widely used in fermentation field, but pigment compounds affect its further application. In this study, nonpolar hyper-cross-linked adsorption resins (HCARs) were synthesized by pendent vinyl groups cross-linking reaction, and were applied to decolorization of molasses. The correlation between the structure and the decolorization performance of HCARs was studied, and the results showed that the Brunauer-Emmett-Teller (BET) surface area and the pore volume of the resin significantly increased to 574.4 m2·g-1 and 1.40 cm3·g-1 after the Friedel-Crafts alkylation reaction with a catalyst dosage of 2.25% at 343 K for 7 h. Furthermore, the decolorization rate of molasses by the HCAR was 74%, and recycle decolorization performance of the resin was stable. The adsorption kinetics results showed that the pseudo-second-order dynamic model could more realistically reflect the decolorization mechanism of molasses on HCARs, and liquid film diffusion is the main rate-limiting step. The results of fixed-bed experiments show that D-ST-DVB resin has a good decolorization effect and recycling ability. Therefore, it is a feasible strategy for the decolorization of molasses with nonpolar HCAR.


Assuntos
Melaço , Poliestirenos , Poliestirenos/química , Bengala , Fermentação
20.
Vet Anim Sci ; 16: 100244, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35372706

RESUMO

Poultry-based foods contribute to human health due to their high nutrient value. Previously, it was shown that short-chain fatty acids (SCFAs) produced by in vitro intestinal fermentation of a molasses and oligofructose mixture (M-O) stimulated iron and calcium transport through the colonic epithelium of laying hens. However, the real impact of including M-O mixture in the diet on the mineral content of poultry products had not yet been demonstrated. In this study, Hy-Line W-36 leghorn hens were assigned into two groups that either received a conventional diet or a diet supplemented with cane molasse and oligofructose, over a period of 42 days. The weight of the animals and their eggs, blood parameters and intestinal epithelium integrity were determined. Intestinal bacteria, their fermentation products, and the mineral content of eggs, bones and muscles were also assessed. The experimental diet proved to be safe, favored the proliferation of SCFA producing bacteria in the intestines, led to higher concentration of acids (mainly SCFA) in the digesta, and induced the elongation of microvilli at the apical tip of enterocytes. Mineral content of eggs and meat were improved after four weeks of feeding with the experimental diet compared to the conventional one. Higher iron content was observed in the edible portion of eggs and leg muscle, and higher calcium content was observed in the egg edible portion and shell in hens fed the supplemented diet. This feeding strategy could be useful to improve the mineral content of poultry products and therefore human nutrition, while diversifying molasses applications.

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