Fermentation Of Sugarcane Bagasse Research Articles

Use of thermophilic bacteria to utilize sugarcane bagasse: Efficient cellulase production, saccharification, and hydrolysate applications

Sugarcane bagasse (SB) a renewable and abundant source of rich fermentable sugars has been reported extensively to produce microbial enzymes and other valuable products. However, most of the SB-based processes require its pretreatment which is an additional step incurring time and cost. In this study, fermentation of SB by bacterial strains without any pretreatment was carried out to obtain crude cellulase preparation. Enzyme mediated saccharification of SB was carried out and the hydrolysate was analyzed for the presence of reducing sugars and free radical scavenging activity. It was found that 65.86, 42.03 and 88.8 IU mL−1 endoglucanase was produced by Brevibacillus borstelensis UE10, Neobacillus sedimentimangrovi UE25 and B. borstelensis UE27, respectively by fermenting SB. Crude cellulase preparation of UE10, UE25, and UE27 was used to saccharify SB which resulted in 1.14, 1.47, and 1.58 mg mL−1 reducing sugars and 1.08, 0.57, and 1.5 mg mL−1 glucose, respectively. Moreover, the hydrolysate also had radical scavenging activity indicating about its possible application in animal feed. The maximum (35.71 %) amount of bioethanol was produced when UE25 fermented the hydrolysate of SB. The strains UE10 and UE27 produced 31.16 and 27.77 % bioethanol, respectively. Furthermore, Fourier transform infrared spectroscopy, scanning electron microscopy and gravimetric analysis showed the impact of cellulase on structure of SB. Hence, this work expands the understanding of the potential of thermophilic bacterial strains to utilize agricultural waste for the synthesis of valuable products.

Optimizing nitrogen removal in constructed wetlands for low C/N ratio wastewater treatment: Insights from fermentation liquid utilization

The inefficient nitrogen removal in constructed wetlands (CWs) can be attributed to insufficient carbon sources for low carbon-to-nitrogen (C/N) ratio wastewater. In this study, sugarcane bagasse fermentation liquid (SBFL) was used as a supplemental carbon source in intermittently aerated CWs to enhance nitrogen removal. The impact of different regulated influent C/N ratios on nitrogen removal and greenhouse gas (GHG) emissions was investigated. Results demonstrated that SBFL addition significantly enhanced the denitrification capacity, resulting in faster NO3--N removal compared to sucrose. Moreover, intermittently aerated CWs significantly improved NH4+-N removal efficiency compared to non-aerated CWs. The highest total nitrogen removal efficiency (98.3 %) was achieved at an influent C/N ratio of 5 in intermittently aerated CWs with SBFL addition. The addition of SBFL resulted in a reduction of N2O emissions by 17.8 %–43.7 % compared to sucrose. All CWs exhibited low CH4 emissions, with SBFL addition (0.035–0.066 mg·m-2h-1) resulting in lower emissions compared to sucrose. Additionally, higher abundance of denitrification (nirK, nirS and nosZ) genes as well as more abundant denitrifying bacteria were shown in CWs of SBFL inputs. The results of this study provide a feasible strategy for applying SBFL as a carbon source to improve nitrogen removal efficiency and mitigate GHG emissions in CWs.

Mitigating nitrous oxide emissions from low carbon to nitrogen ratio wastewater treatment: Utilizing sugarcane bagasse fermentation liquid for constructed wetlands

Sugarcane bagasse was recycled to produce fermentation liquid (FL) as a supplementary carbon source that was added to constructed wetlands (CWs) for regulating influent carbon to nitrogen ratio (C/N), and then being applied to investigate nitrogen transformations and greenhouse gas emissions. Results showed that this FL achieved faster NO3−-N removal and lower N2O fluxes than sucrose did, and the lowest N2O flux (67.6 μg m−2h−1) was achieved when FL was added to CWs in a C/N of 3. In contrast, CH4 emissions were higher by the FL addition than by the sucrose addition, although the fluxes under both additions were in a lower range of 0.06–0.17 mg m−2h−1. The utilization of FL also induced significant variations in microbial communities and increased the abundance of denitrification genes. Results showed the application of FL from sugarcane bagasse can be an effective strategy for improving nitrogen removal and mitigating N2O emissions in CWs.

Effect of yeast (S.cerevisiae) fermented sugarcane bagasse and concentrate on nutrient intake, digestibility, and growth performance of sheep

Effect of yeast (S.cerevisiae) fermented sugarcane bagasse and concentrate on nutrient intake, digestibility, and growth performance of sheep

The effectiveness of additional silage of fish ofal and bagasse fermentation on biomass and population of silk worm (Tubifex tubifex)

The purpose of this study was to determine the effect of giving catfish offal silage and sugarcane bagasse fermentation to the biomass The method used in this research is experimental using Completely Randomized Design (CRD). The treatments were 413 gram (100%) rice field mud, 206.5 gram rice field mud + 75% fish offal silage + 25% bagasse fermentation, 206.5 gram rice field mud + 50% fish offal silage + 50% bagasse fermentation, rice field mud 206.5 grams + 25% silage of fish offal + 75% bagasse fermentation. Each treatment was repeated five times. The results showed that the highest peak of silk worm biomass with 206.5 grams of rice field mud culture + 25% fish offal silage + 75% bagasse fermentation with an average of 22.25 grams and the lowest biomass was produced on 406 grams (100%) mud media. Rice fields with an average of 7.15 grams. The highest population of silkworms was found in 206.5 gram rice field mud media + 25% fish offal silage + 75% bagasse fermentation obtained 6651 ind, the lowest population in 406 gram (100%) rice field mud media with an average of 2.263 ind.

Effects of replacing hybrid giant napier with sugarcane bagasse and fermented sugarcane bagasse on growth performance, nutrient digestibility, rumen fermentation characteristics, and rumen microorganisms of Simmental crossbred cattle.

This study investigated the effects of replacing hybrid giant napiers with sugarcane bagasse and fermented sugarcane bagasse on the growth performance, apparent nutrient digestibility, rumen fermentation characteristics, and rumen microorganisms of Simmental crossbred cattle. Twenty-one Simmental crossbred cattle with similar initial body weight (363.42 ± 8.67 kg) were randomly divided into three groups: Group CON (20% hybrid giant napier +45% distillers grains +35% concentrate mixture), Group SB (20% sugarcane bagasse +45% distillers grains +35% concentrate mixture), and Group FSB (20% fermented sugarcane bagasse +45% distillers grains +35% concentrate mixture). The average daily weight gain in the SB group was lower than in the CON group, no significant difference was found between the CON and FSB groups. The feed conversion ratio of the CON and FSB groups was lower compared to the SB group. The apparent digestibility of neutral detergent fiber and acid detergent fiber in the SB group was lower than in the CON group, no significant difference was found between the CON and FSB groups. The levels of NH3-N, microbial protein, acetate, propionate, butyrate, isobutyrate, and total volatile fatty acids were higher in the CON and FSB groups than in the SB group, no significant difference was found between the CON and FSB groups. The relative abundances of Christensenellaceae_R-7_group, Rikenellaceae_RC9_gut_group, Prevotellaceae_UCG-003, Saccharofermentans, and Eubacteriumcoprostanoligenes_group were lower in the CON and FSB groups compared to the SB group. The relative abundance of Succiniclasticum was highest in the FSB group, followed by the CON group and then the SB group. Correlation analysis showed that the relative abundance of Succiniclasticum was positively correlated with propionate and NH3-N content, while the relative abundance of Rikenellaceae_RC9_gut_group was inversely correlated with NH3-N content. Gene function prediction indicated that fermented sugarcane bagasse promoted rumen microbial amino acid metabolism. In conclusion, replacing hybrid giant napiers with 20% sugarcane bagasse negatively affected the growth performance of Simmental crossbred cattle, while the addition of 20% fermented sugarcane bagasse had no adverse effects on growth performance and rumen fermentation characteristics, and did not alter the abundance of the rumen core flora in Simmental crossbred cattle.

Recovery and characterization of cellulosic ethanol from fermentation of sugarcane bagasse

Industrial production of ethanol by fermentation using renewable feedstock such as sugarcane stalks has been demonstrated as a sustainable fuel chain in Brazil. This work focused on the production of cellulosic ethanol from sugarcane bagasse in a pilot scale unit by applying the current bioprocessing strategies with the aim of recovering and characterizing the end products. The feedstock was pretreated at 190 °C and a residence time of 10 min. Enzymatic hydrolysis was performed with commercial cellulolytic enzymes. Fermentation’s substrates were formulated with hydrolysate and supplemented with 8%wt sugarcane molasses. The fermentations were set up to mimic the conventional industrial fermentation in Brazil’s ethanol distilleries at high cell density with cell recycling. The fermentation resulted in a reproducible performance by the yield of 0.49 g/g, productivity of 6.96 g/(L∙h), and cell viability of 95.3%. Ethanol was recovered in a lab-scale distillation batch system. Distilled fractions showed higher content of higher alcohols and sulfur content than the standard specification of ANP (National Agency of Petroleum - Brazilian Agency) for ethanol fuel. The distillation bottom product (vinasse) presented most characteristics suitable for fertilizer or biogas applications, except for sodium and sulfate content. Therefore, for a successful technology, transference processing adjustments should be made to make the product commercially suitable and the side stream compatible for disposal as fertilizer or digestion for biogas production.

Penambahan Inokulum yang Berbeda pada Ampas Tebu Fermentasi Terhadap Kualitas Nutrisi

Sugarcane bagasse is an agricultural waste that could be processed into ruminant alternative feed. Sugarcane bagasse processing was very necessary to improve the nutritional as animal feed using fermentation application which was one way to increase the nutritional of sugarcane bagasse using cow feces inoculum and EM-4 (Effective Microorganism-4). The purpose of this study was to determine the effect nutritional quality of fermented sugarcane bagasse using different types of inoculum. This study used a Completely Randomized Design (CRD) with 4 treatments and 5 replications that are ; P0: sugarcane bagasse without inoculum addition (control), P1: sugarcane bagasse + 5% cattle feces, P2: sugarcane bagasse + EM-4 10%, P3: sugarcane bagasse + 5% cattle feces + E-4 10%. The parameters measured include dry content, crude protein, crude fiber, and crude fat. The data were analyzed using Analysis of Variance (ANOVA) and continued with Duncan’s Multiple Range Test (DMRT). The results showed that a mixture of 5% cow feces and 10% EM-4 had a very significant effect (P <0.01) to increase crude protein ​​and significantly (P <0.05) to reduce crude fiber. The conclusion of this research was the addition of 5% cow feces inoculum and 10% EM-4 (P3 treatment) was the best treatment because it increased crude protein content and decreased crude fiber

Creation of microbial bio‐aroma wheel design according to smell attributes and multivariate exploratory methods

AbstractMicrobial bio‐aroma synthesized from biowaste, and its marketing is an emerging aspect of future research due to their benefits. However, the sensory lexicon of bio‐aroma has not yet been developed so far. This study aims to identify the smell characteristics of bio‐aroma produced by fermentative yeast Kluyveromyces marxianus by solid‐state fermentation, where the sample was extracted from fermented sugarcane bagasse (FSB), sweet lemon peel (FSLP), and pomegranate peel (FPP). A group of 49 respondents participated in this sensory analysis; the generated data reveal that a total of 29, 35, and 26 aroma essences gets from FSB, FSLP, and FPP, respectively. Multiple factor analysis was performed using XLSTAT 2022.1 version, and hierarchical clustering was used to classify the different cluster levels of aroma attributes. An aroma wheel is designed according to the attributes of classified aroma (smell). This bio‐aroma has prospects for application in food, pharmaceuticals, and cosmetic products.Practical ApplicationsThis fermented bio‐waste aroma lexicon will be helpful to academicians, researchers, flavorist and consumers to understand the precise description and basic terms. It also make them aware about a natural alternative source of flavor and aroma ingredients. It can be used as a sustainable additive for food, pharmaceutical, and cosmetic industries in the future.

Ethanol production using the whole solid-state fermented sugarcane bagasse cultivated by Trichoderma reesei RUT-C30 supplemented with commercial cellulase

Industrial ethanol production usually requires the costly use of commercial cellulase. Herein, we describe the direct use of cellulase produced by Trichoderma reesei RUT-C30 with sugarcane bagasse (SCB) as a substrate for the production of ethanol. The pretreated SCB supplemented with wheat bran (weight ratio of 4:1) was used for T. reesei cellulase production by solid-state fermentation. The cellulase activity titers of 5.5 ± 0.7 FPU/gdm was achieved. The activity increased to 15.0 ± 0.9 FPU/gdm when lactose was used as an inducer. The cellulase contained SCB (CSCB) was used directly as the raw material for ethanol production by Kluyveromyces marxianus at 40 °C, yielding 14.1 ± 1.8% (w/w) of ethanol. Supplementing 5 FPU/gdm of commercial cellulase (Cellic® CTec 2) to CSCB improved the ethanol yield to 30.3 ± 0.4% (w/w). Supplementing Cellic® CTec 2 provided large amount of β-glucosidase activity to CSCB, which hydrolyzes cellobiose to glucose, thereby preventing the inhibition of cellobiose to exoglucanase and endoglucanase. This study demonstrate the feasibility of integrating direct utilization of CSCB without further processing, conversion of CSCB to fermentable sugars, and fermentation of yeast to ethanol in a single reactor. This may be the most efficient way to convert biomass to valuable ethanol.

Preparation of a Pectinase-Enriched Multienzyme under Solid State Fermentation of Sugarcane Bagasse

Enzyme mediated degradation of lignocellulosic biomass is an important step in waste-biorefineries. Multienzyme preparations can effectively degrade complex materials and, hence, can be applied in biorefineries. Here, an agro-industrial waste, sugarcane bagasse, was used to produce a bacterial multienzyme. The bacterial strains including B. thuringiensis B45, B. velezensis BF3 and B. amyloliquefaciens B987 exhibited their growth at temperatures from 30–50 °C in the presence of 2% salt. The isolates B45, BF3 and B987 were able to produce endoglucanase, xylanase and pectinase, respectively. Therefore, it was aimed to obtain a multienzyme preparation by cultivating the bacterial consortium under a solid-state fermentation of untreated and chemically treated sugarcane bagasse. The results showed that the titres of cellulase and xylanase were generally higher when the strain B45 cultivated at the start of the fermentation. Interestingly, the degradation of cellulose and hemicellulose present in sugarcane bagasse by the strains B45 and BF3 rendered the mere pectin component available to the pectinolytic strain B987. The degradation of SB by the consortium was confirmed by gravimetric analysis and scanning electron microscopy. The study showed that the bacterial strains can be cultivated under solid-state fermentation to obtain industrially important enzymes.

Synergistic effects of paper mill sludge and sulfonated graphene catalyst for maximizing bio-hydrogen harvesting from sugarcane bagasse de-polymerization

In this study, hydrogen harvesting from fermentation of sugarcane bagasse (SCB) was promoted by maintaining synergism between sulfonated graphene (SGR) catalyst and paper mill sludge (PMS). The sulfonic acid (–SO3H) groups in the catalyst played a major role in destructing the β-1,4 glycosidic bonds of sugarcane bagasse, releasing readily biodegradable sugars into the fermentation medium. The cellulose, hemicellulose, and lignin conversion efficiency were improved by 127.5%, 495.0%, and 109.2%, respectively with 20 mgSGR/gVS catalyst addition, compared with the control samples. These values were also higher than those obtained by non-sulfonated graphene catalyst. The hydrogenation of sugarcane bagasse was maximized at a sulfonated graphene catalyst dosage of 60 mgSGR/gVS, providing the highest hydrogen harvesting of 4104 ± 321 mL. This was associated with an increase of the Proteobacteria phyla up to 52.0%, Firmicutes phyla to 13.9%, and Acinetobacter sp. to 39.8% compared with only 37.0%, 11.3% and 11.1% in the control assay respectively. Moreover, sulfonated graphene catalyst supplementation promoted the acetate fermentation reaction pathway by increasing the acetate/butyrate ratio up to 4.1. Nevertheless, elevating the catalyst dosage up to 120 mgSGR/gVS reduced the hydrogen harvesting (1190 ± 92 mL) due to the release of furfural (1.76 ± 0.02 g/L) in the fermentation cultures, deteriorating the microbes’ internal composition and metabolism bioactivities. Finally maximizing the hydrogen productivity from sugarcane bagasse is feasible by incorporation of paper mill sludge and sulfonated graphene catalyst at dosage not exceeding 60 mgSGR/gVS. However, investigating the recyclability and disposal of digestate containing sulfonated graphene catalyst and the associated economic feasibility needs more attention in the future.

Feeding Thai Native Sheep Molasses Either Alone or in Combination with Urea-Fermented Sugarcane Bagasse: The Effects on Nutrient Digestibility, Rumen Fermentation, and Hematological Parameters.

Simple SummaryA key strategy for attaining value-added and ecologically sustainable operations is the conversion of agro-industrial waste into animal feed. Sugarcane bagasse, a fibrous byproduct of the sugar-refining process, is widely available. Bagasse, however, has low nutritional value and a high quantity of indigestible fiber, which causes low digestibility and, as a result, poor animal performance. Ensiled bagasse’s fermentation properties improved after being treated with molasses and urea. Sheep’s ability to digest crude protein was increased by mixing fermented sugarcane bagasse with 10% molasses and 3% urea without having an adverse impact on the ruminal fermentation or the animal’s hematological parameters.The purpose of this study was to find out how adding molasses to fermented sugarcane bagasse (FSB) alone or in combination with urea affected sheep’s rumen fermentation, hematological parameters, and ability to digest nutrients. Four Thai native sheep with an initial body weight (BW) of 20.87 ± 1.95 kg and 11 ± 1.0 months old were assigned to a 4 × 4 Latin square design with 4 periods of 14-d adaptation and 7 d of sample collection. Each treatment received a different combination of experimental roughage as follows: FSB without additives (T1), FSB + 10% molasses (T2), FSB + 20% molasses (T3), and FSB + 10% molasses + 3% urea (T4). The concentrate diet was fed twice daily at 2% BW, while roughage sources were provided ad libitum for each treatment. The crude protein (CP) digestibility in the T2 and T3 groups was higher (p < 0.05) than in the FSB group without additions, with the T4 group having the highest (p < 0.05). Although there were no significant differences in blood glucose, packed cell volume, ruminal pH, ammonia–nitrogen (NH3-N), propionic acid, or acetic acid, the plasma urea nitrogen (PUN) at 0 h was highest in the T4 group (p < 0.05) compared with the other groups. However, the proportion of butyric acid tended to be higher in all FSB groups with additives. Thus, the current experiment concluded that the addition of molasses alone or in combination with urea had positive effects on pH and LAB population, and including both together in FSB improved the CP digestibility of sheep. In conclusion, FSB with 10% molasses and 3% urea might be used as an alternate roughage source for ruminants without affecting the animal’s ruminal fermentation or hematological parameters.

Use of Ionic Liquid Pretreated and Fermented Sugarcane Bagasse as an Adsorbent for Congo Red Removal

A large amount of industrial wastewater containing pollutants including toxic dyes needs to be processed prior to its discharge into the environment. Biological materials such as sugarcane bagasse (SB) have been reported for their role as adsorbents to remove the dyes from water. In this study, the residue SB after fermentation was utilized for the dye removal. A combined pretreatment of NaOH and methyltrioctylammonium chloride was given to SB for lignin removal, and the pretreated SB was utilized for cellulase production from Bacillus aestuarii UE25. The strain produced 118 IU mL−1 of endoglucanse and 70 IU mL−1 of β-glucosidase. Scanning electron microscopy and FTIR spectra showed lignin and cellulose removal in fermented SB. This residue was utilized for the adsorption of an azo dye, congo red (CR). The thermodynamic, isotherm and kinetics studies for the adsorption of CR revealed distinct adsorption features of SB. Untreated SB followed Langmuir isotherm, whereas pretreated SB and fermented SB obeyed the Freundlich isotherm model. The pseudo-second-order model fitted well for the studied adsorbents. The results of thermodynamic studies revealed spontaneous adsorption with negative standard free energy values. Untreated SB showed a 90.36% removal tendency at 303.15 K temperature, whereas the adsorbents comprised of pretreated and fermented SB removed about 98.35% and 97.70%, respectively. The study provided a strategy to utilize SB for cellulase production and its use as an adsorbent for toxic dyes removal.

Performance of Yeast Microbial Fuel Cell Integrated with Sugarcane Bagasse Fermentation for COD Reduction and Electricity Generation

The purpose of this analysis is to evaluate the efficiency of the Microbial Fuel Cell (MFC) system incorporated with the fermentation process, with the aim of reducing COD and generating electricity, using sugarcane bagasse extract as a substrate, in the presence and absence of sugarcane fibers. There is a possibility of turning bagasse extract into renewable bioenergy to promote the sustainability of the environment and energy. As a result, the integration of liquid fermentation (LF) with MFC has improved efficiency compared to semi-solid state fermentation (S-SSF). The maximum power generated was 14.88 mW/m2, with an average COD removal of 39.68% per cycle. The variation margin of the liquid fermentation pH readings remained slightly decrease, with a slight deflection of +0.14 occurring from 4.33. With the absence of bagasse fibers, biofilm can grow freely on the anode surface so that the transfer of electrons is fast and produces a relatively high current. Experimental data showed a positive potential after an effective integration of the LF and MFC systems in the handling of waste. The product is then simultaneously converted into electrical energy. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Multi‐enzymatic recovery of fungal cellulases (Aspergillus niger) through solid‐state fermentation of sugarcane bagasse

AbstractIn this study, the optimum conditions for the multi‐enzymatic recovery of cellulases produced by Aspergillus niger were investigated using sugarcane bagasse. Two extraction methods were investigated: the two‐stage solid–liquid extraction (SLE) followed by ultrasound‐assisted extraction (UAE), and the single‐stage SLE. The ultrasound effects were evaluated using a Doehlert design, in which the pH (5.0–9.0) and sonication power (0.8–2.0 W ml−1) were independent variables. For the single‐stage SLE, temperature (25–45°C), time (10–60 min), and pH (5.0–9.0) were analyzed using the Box–Behnken design. Both processes were monitored to evaluate FPase, CMCase, and β‐glucosidase (U ml−1) activities. The maximum enzymatic activities (EA) obtained for FPase, CMCase, and β‐glucosidase in the SLE–UAE were 0.352, 0.321, and 1.412 U ml−1, respectively. Unlike in most previous studies, sonication was insignificant (p &lt; 0.05) with respect to the enzymatic complex within the evaluated ranges. Moreover, sonication changed the EA when lower than 1.2 and higher than 1.6 W ml−1, mainly inhibiting the EA of β‐glucosidase. The single‐stage SLE was more effective than the two‐stage SLE–UAE, and the maximum EA values for FPase, CMCase, and β‐glucosidase were 0.354, 0.303, and 3.135 U ml−1, respectively. The single‐stage process was better because it consumed less energy, required simpler equipment, and provided higher efficiency in a shorter time. This study will improve diversified enzyme extraction from sugarcane bagasse, reduce enzyme production costs, and enhance bagasse utilization.

Enzymatic profiles of hydrolysis of lignocellulosic materials from Aspergillus terreus strains isolated from the rumen of beef cattle from Brazil

Degradation of lignocellulosic materials by Aspergillus terreus isolated from rumen fluid, fungal biomass, in vitro substrate degradation, pH at end of incubation, concentrations of total protein (TP) and total cellulase (TC) were performed.In prior assay, submerged fermentations of sugarcane bagasse (SB) or Urochloa decumbens (UD) by five A.terreus isolates were performed.Subsequently, submerged fermentation using the two most promising isolates were evaluated comparing two nitrogen sources for cellulases, CMCases, avicelase and xylanases productions at 0, 72, 144, 216 and up to 288 h, in a factorial (2 × 2 × 5). During fermentation with UD and SB, showing lignin values 7.50 and 6.15%, respectively, the enzymatic activities at 50 °C were higher than those observed in the pH and temperature simulating the rumen (39 °C), allowing us to determine the optimal conditions under which the enzymes of interest may function in the animal model.The interaction between substrates and the evaluated periods was significant. Specifically for UD, the isolates V15 and V22 produced 226.14 and 210.72 nmol/L.s, respectively, which concentrations did not differ from each other.The isolates of this fungus showed growth ranging from 669 mg/L for the V79 isolate, using UD , and o 19,695 mg/L for the V22 isolate using SB after 216 h in medium supplemented with ammonium sulfate.Total protein levels were influenced by the substrates evaluated and by fermentation periods. The activity carboxymethylcellulases (CMCases) and xylanases presented values between 15.42 and 92.51 nmol/L.s for SB and from 5.14 to 226.14 nmol/L.s for UD fermentations. Using urea or ammonium sulfate, the V79 isolate in SB fermentation and the V49 isolate in UD fermentation, at 288 h, presented the highest rates of TP. The quantifications of TC in pH 4.5 at 50 °C were higher presenting 12,380.97 nmol/L.s and PT 347.575,0 nmol/mg.s, respectively by biomass, than those produced at pH 6.8 and 39 °C. The two selected A. terreus isolates from bovine rumen showed potential to use in the industrial microbiology and as additives to diets of ruminants. • Total protein contents showed significant differences for substrate interactions as a function of nitrogen source • Urea treatment resulted in higher pH values for both isolates and substrates, unlike fermentation containing ammonium sulfate, which showed acidic pH values • Additionally, only when analyzed as a function of substrate (sugarcane bagasse and U. decumbens ) for the following parameters: dry matter degradation, total proteins, total cellulase, total protein by total cellulase, xylanase, total protein by xylanase, xylanase by biomass, similarly significant differences were observed (P < 0.05). • The substrates influenced only the degradation rate and the isolates did not influence the evaluated parameters. However, nitrogen source influenced degradation and enzyme production

Fluorescent xylitol carbon dots: A potent antimicrobial agent and drug carrier.

Biomolecular carbon dots (CDs) have immense potential for various industries due to exceptional bioactivity, biocompatibility, low toxicity, and biodegradability. In the present work xylitol (Xlt), a natural sweetener produced by microbial fermentation of sugarcane bagasse (71.98% conversion) has been used for CDs preparation by microwave-assisted carbonization in the presence of ethylene diamine (EDA). The resultant xylitol carbon dots (XCDs) were irregular shaped, rough with an average size of 8.88 nm and exhibiting fluorescence between 400 and 450 nm. The presence of EDA preserves the native chemical structure of Xlt even after exposure to microwaves. Purified XCDs were conjugated (AM-XCD) with ketoconazole and tetracycline for fungi and bacteria, respectively. In comparison to Xlt, XCDs have higher inhibitory potential and reduced dosage size of antimicrobials against Cryptococcus neoformans, Candida albicans, Streptococcus pyogenes, and Escherichia coli by 75%, 75%, 87.50%, and 50%, respectively. For Listeria monocytogenes and Salmonella typhi also inhibitory potential was increased by 14.68% and 21.38%. Increased efficacy advocated the improved drug delivery in the presence of XCDs. However, no inhibitory effect was recorded against DU145 (human prostate cancer) and HCT-15 (human colon adenocarcinoma) cell lines. The findings of the current work suggested the possible use of Xlt as an important antimicrobial agent besides an efficient drug carrier in healthcare.

Carbon catabolite repression occurrence in photo fermentation of ethanol-rich substrates

The paper investigates the phenomenon of Carbon Catabolite Repression occurring during photo fermentation of ethanol-rich effluents, which usually contain ethanol as main carbon source, and glycerol as secondary one. The study was conducted using mixed phototrophic cultures, adopting, as substrate, the effluent produced by the alcoholic fermentation of sugar cane bagasse. In order to elucidate the phenomenon, experimental tests were carried out using two different ethanol to glycerol ratios. Results were compared with those resulting from pure ethanol and glycerol conversion. According to the obtained data, as a result of Carbon Catabolite Repression occurrence, the presence of glycerol negatively affects hydrogen production. Indeed, part of the ethanol source is converted to biomass and polyhydroxybutyrate rather than to hydrogen. In more details, the presence of glycerol determines a drop of the hydrogen production, which goes from 12 % to 32 %, according to the ethanol/glycerol ratio, compared to the production obtained from fermentation of ethanol alone. Therefore, to promote the hydrogen production, it is advisable to apply strategies to produce low glycerol concentrations in the ethanol production stage.

Growth performances, nutrient digestibility, ruminal fermentation and energy partition of Thai native steers fed exclusive rice straw and fermented sugarcane bagasse with Lactobacillus, cellulase and molasses.

The study aimed to evaluate the effect of sugarcane bagasse feeding treated with Lactobacillus casei TH14 (L. casei TH14), cellulase and molasses (BG) on nutrient digestibility, ruminal fermentation, energy partition and growth performances of Thai native steers compared to conventional feeding of rice straw (RS). Eight Thai native steers (144±19.5kg of initial body weight) were randomly allocated to two roughage sources in a completed randomized design: RS (n=4) and BG (n=4). The feeding trial lasted for 90days plus 21days for treatment adaptation. The results showed that the BG group showed (p<0.05) greater intake (2.34 vs 2.02kg/day), total intake (3.90 vs 3.55kg/day) and average daily gain (0.27 vs 0.23kg/day) while feed conversion ratio was lower compared to RS group. The BG group had a greater (p<0.05) organic matter and acid detergent fibre intake than the RS group as well as dry matter and neutral detergent fibre digestibility. The steers fed RS and BG were significantly (p<0.05) different for total volatile fatty acids and propionic acid at 4h after offering the diet. The intake of nitrogen (g/day) and apparent nitrogen absorption was significantly (p<0.05) higher for BG than the RS group while nitrogen excretion in faeces was significantly lower in RS than the BG group. BG group showed significantly (p<0.05) greater gross energy intake and digestible energy partition when compared to the RS group. In conclusion, feeding BG enhanced feed utilization, growth performance, ruminal fermentation, nitrogen utilization and energy utilization.