Search

Rice wine (RW) and its fermentation residue, rice wine lees (RWL), are prepared using a traditional starter culture (TSC). The TSC contains a combination of different fungal and bacterial species that are variable in composition. This study evaluated the effects on the nutritional profile and the sensory qualities of RWL using various combinations of these fungal species as starter cultures. We isolated the three most abundant fungal species in TSC and found them to be Rhizopus oryzae (RO), Mucor indicus (MI), and Saccharomyces cerevisiae (SC). Although sensory evaluation revealed that the RWL produced using the RO+SC was the most preferred (n = 30) in color, aroma, sweetness, bitterness, and clarity, no significant differences were observed compared to when RO+MI+SC was used. Moreover, the RO+MI+SC-produced rice wine lees demonstrated the highest nutritional composition in terms of the following: crude protein content (11.12±0.08%), total energy (412.96±0.07 kcal/100 g), essential amino acids, and vitamin content. Hence, the combination of these three fungal species, RO, MI, and SC, as a starter culture in rice wine fermentation gives rise to rice wine lees with higher nutritional value than using the traditional rice wine starter culture. [ABSTRACT FROM AUTHOR]

A five year old girl with life-long TPN dependence for short gut syndrome presented with two episodes of non-fatal Mucor indicus central line associated blood stream infection (CLABSI). Each episode occurred fifteen months apart, without any evidence of ongoing mould infection whilst off antifungal therapy in the intervening time period. Both episodes were treated with removal of the infected central venous catheter (CVC) and 6 weeks of intravenous liposomal amphotericin B and/or posaconazole, with good clinical, microbiological, and radiological response. The possibility of gut translocation is supported by the repeated isolation of Mucor indicus in cases of intestinal mucormycosis. To our knowledge, this is the first case of recurrent episodes of blood culture positive mucormycosis in a single patient. Mucor indicus blood stream infection may differ significantly from invasive mucormycosis caused by other species.

Background: Mucormycosis commonly occurs in immunosuppressed patients with hematological diseases, which can be life-threatening. However, many cases are often misdiagnosed due to lack of specific clinical manifestations. Additionally, the traditional blood culture or serological testing, with a high false-negative rate, is time-consuming. Thus, precise and timely diagnosis of infections is essential for the clinical care of infected patients. Case presentation: We report a 29-year-old Chinese man with acute myeloid leukemia (AML) who developed febrile neutropenia after the first course of induction chemotherapy. He received empirical antibiotics, which did not relieve his symptoms. No pathogen was detected by traditional microbiologic assays, while Mucor indicus was identified by metagenomic next-generation sequencing (mNGS) in the blood specimen. Liposomal amphotericin B (LAmB) was used, resulting in the patient's temperature returning to normal. A few days later, abdominal computed tomography (CT) scan showed multiple liver abscesses; fluorescence staining, histopathology, and mNGS identified the causative agent--M. indicus. Posaconazole was combined with LAmB as long-term antifungal treatment. Finally, the patient received allogeneic hematopoietic stem cell transplantation successfully after controlled infection. During follow-up 1 year after transplantation, the number of liver abscesses was reduced to one and remained stable. Conclusion: This report described the first case of an AML patient diagnosed with culture-negative disseminated infections caused by M. indicus leading to rare hepatic manifestations using mNGS of peripheral blood and liver biopsy. LAmB combined with posaconazole was given in time, resulting in a favorable outcome. mNGS is a new method that assists in detecting the probable pathogen and increases the accuracy of identifying an etiology. [ABSTRACT FROM AUTHOR]

A five year old girl with life-long TPN dependence for short gut syndrome presented with two episodes of non-fatal Mucor indicus central line associated blood stream infection (CLABSI). Each episode occurred fifteen months apart, without any evidence of ongoing mould infection whilst off antifungal therapy in the intervening time period. Both episodes were treated with removal of the infected central venous catheter (CVC) and 6 weeks of intravenous liposomal amphotericin B and/or posaconazole, with good clinical, microbiological, and radiological response. The possibility of gut translocation is supported by the repeated isolation of Mucor indicus in cases of intestinal mucormycosis. To our knowledge, this is the first case of recurrent episodes of blood culture positive mucormycosis in a single patient. Mucor indicus blood stream infection may differ significantly from invasive mucormycosis caused by other species. [ABSTRACT FROM AUTHOR]

The aim of the research was to analyze the fermentability of sugarcane bagasse prehydrolysates using Mucor indicus. The prehydrolysates were obtained by acid prehydrolysis of sugarcane bagasse and were detoxified before fermentation. A mold strain was also adapted to the inhibitors contained in the prehydrolysates. The production of ethanol and sugar consumption were investigated under aerobic and oxygen limited conditions. For the original strain, the consumption of sugars was incomplete and ethanol was produced at a yield of 0.39± (0,02) g g-1. The increased tolerance of M. indicus to the inhibitors resulted in a complete fermentation with total glucose consumption. Most of the xylose was consumed in all experiments, with the highest consumption in aerobic fermentations. Ethanol was the main product of fermentation and its yield was 0.41 ± (0,02) g g-1 at oxygen limited conditions and 0.37 ± (0,02) g g-1 at aerobic conditions. The use of other carbohydrates besides the monosaccharides was also investigated. Another advantage of M. indicus detected during the investigation was its ability to ferment pentoses, hexoses and oligosaccharides.

Bio‐nanocomposites based on starch are reinforced by different percentages of chitin nanofibers (ChNFs) and compatibilized by glycerol. Nanofibers are extracted from Mucor indicus fungus through different chemo‐mechanical pretreatments. The mechnical, chemo‐physical, and morphological properties of the nanocomposite starch films were evaluated and compared with the unfilled thermoplastic starch (TPS) film. Based on the obtained results, Young's modulus of the film at 5 wt.% ChNFs indicated 239% enhancement compared to the TPS film due to the existence of good interactions between starch and ChNFs. Moreover, the ultimate strength of the reinforced film at 5 wt.% ChNFs and the unreinforced counterpart are found to be 5.5 and 1.74 MPa, indicating 216% improvement; however, the elongation at break of the films decreases from 59.3% to 19.3% by adding 5 wt.% ChNFs. In addition, the moisture absorption of the film decreases after the incorporation of ChNFs. Based on the morphological study, ChNFs increase the roughness of the starch matrix with a homogenous morphology revealing the good dispersion of nanofibers in the TPS film. Finally, the nanocomposite film with 5 wt.% ChNFs show the best properties to employ for bio‐film applications. [ABSTRACT FROM AUTHOR]

Chitin nanofibers (ChNFs) were extracted from Mucor indicus by a purification method followed by a mechanical treatment, cultivated under obtained optimum culture medium conditions to improve fungal chitin production rate. A semi synthetic media containing 50 g/l glucose was used for cultivation of the fungus in shake flasks. The cell wall analysis showed that N -acetyl glucosamine (GlcNAc) content, which is an indication of chitin content, was maximum in presence of 2.5 g/l H 3 PO 4 , 2.5 g/l of NaOH, 1 g/l of yeast extract, 1 mg/l of plant hormones, and 1 ml/l of trace metals. The chemical characterizations demonstrated that the isolated fibers had a degree of deacetylation lower than of 10%, and were phosphate free. The FTIR results revealed successful removal of different materials during the purification step. The FE-SEM of fibrillated chitin illustrated an average diameter of 28 nm. Finally, X-ray diffraction results showed that the crystallinity index of nanofibers was 82%. • The optimization of cultivation conditions for enhancement of the chitin production by M. indicus fungus. • The isolation of chitin fibers from cell wall of the filamentous fungus M. indicus through purification. • The characterization of Fungal chitin nanofibers were isolated by mechanical grinding of fungal chitin. • The chitin nanofibers had an average diameter of 28 nm and the crystallinity index of 82%. [ABSTRACT FROM AUTHOR]

Mucor indicus with different morphologies was used for ethanol production and Pb2+ biosorption. With increasing Pb2+ concentration in the cultivation medium, the fungus morphology changed from purely filamentous to mostly filamentous and the biosorption capacity was increased. The maximum adsorption capacity predicted by Langmuir model was 118 mg/g for purely filamentous form. All morphologies were also cultivated in the presence of high Pb2+ concentration (300 mg/L) in consecutive stages. After the first stage of cultivation, the live biomass was separated and cultivated in a new medium similar to the first stage and cultivation was performed within five stages. All morphologies of M. indicus were able to grow and produce ethanol in the presence of lead at all stages but with lower yields than those cultivated in the absence of lead. The highest ethanol yields of 0.46 and 0.35 g ethanol per g consumed glucose were obtained by mostly filamentous morphology at the first and the last stages, respectively. The presence of lead decreased the glucose consumption rate of all morphologies and the yeast-like morphology consumed glucose within a shorter time than the other morphologies. Different morphologies were able to adsorb lead ions considerably (97–99%) within the five consecutive stages.

BACKGROUND: One of the most important species used to ferment Chinese turbid rice wine (CTRW) at an industrial‐scale level is Rhizopus oryzae, although the flavor of CTRW fermented by pure R. oryzae is inferior to that of traditional CTRW. RESULTS: Mucor indicus was used as a cooperative species to improve the flavor of CTRW presented by R. oryzae. The flavor compounds in different fermentation stages were determined by headspace solid‐phase microextraction–gas chromatography–mass spectrometry and high‐performance liquid chromatography. It was noted that the M. indicus and R. oryzae co‐culture changed the profiles of flavor compounds in CTRW, including esters, higher alcohols, amino acids and organic acids, and also significantly enhanced the concentration of sweet amino acids, fruity and floral esters, and higher alcohols. Sensory evaluation demonstrated that the CTRW fermented by M. indicus and R. oryzae had a more intense aroma, harmonious taste, continuation and full body mouth‐feel because of more abundant flavor compounds. CONCLUSION: Mucor indicus is a promising species for co‐culture with R. oryzae to improve the flavor of CTRW. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In a novel valorization approach for simultaneous pectin extraction and pretreatment (SPEP) of citrus waste (CW) by dilute nitric acid and ethanol, almost all of the CW was converted to bio-derived chemicals in a single-step process at a low/moderate temperature. The SPEP was performed at different temperatures (70 °C and 80 °C), pH (1.8, 3.0, and 4.3), and extraction times (2 h and 3 h) with a full factorial design. The maximum pectin yield of 45.5% was obtained at pH 1.8, 80 °C, and 2 h. The pectin yields at pH 1.8 were much higher than at pH 4.3 and 3. Also, the degree of methyl-esterification at pH 1.8 was higher than 50%, whereas at the higher pH, low methoxyl pectins were extracted. The treated CW obtained after the SPEP, free from limonene, was subjected to separate cellulolytic enzymatic hydrolysis and ethanolic fermentation. The glucose yields in the enzymatic hydrolysates were higher for the CW treated at pH 1.8. The fermentation of the enzymatic hydrolysates by Mucor indicus resulted in fungal biomass yields in the range of 355 to 687 mg per g of consumed sugars. The optimum conditions for obtaining the maximum SPEP yield (glucose + pectin (g) / raw material (g))*100) were pH 1.8, 80 °C, and 2 h, which resulted in a yield of 58.7% (g/g CW).

Mucormycosis is a rare fungal infection caused by Mucor indicus. Phylogenetic analysis of many M. indicus isolates, mainly sampled from different clinical and environmental specimens collected worldwide, revealed two genotypes, I and II, based on ITS and D1/D2 LSU rDNA sequences. A retrospective review of the literature revealed 13 cases. Eight (76.9%) patients had disseminated infections, and the overall mortality rate was 30.7%. A pulmonary infection caused by M. indicus genotype I in a liver transplant recipient was disseminated to include the skin and was successfully treated with liposomal amphotericin B and aggressive surgery. M. indicus can infect a wide variety of patients with no real preference for the site of infection. We concluded that M. indicus has emerged as a significant cause of invasive mycosis in severely immunocompromised patients worldwide. Early diagnosis and initiation of appropriate therapy could enhance survival in these immunocompromised patient populations.Emerging Microbes & Infections (2017) 6, e63; doi:10.1038/emi.2017.51; published online 12 July 2017

Introduction: Xylan is the main hemicellulosic polymer in a number of lignocelluloses which can be hydrolyzed by xylanolytic enzymes. One of the main ways for enzymes production is solid state fermentation (SSF). The ability of three fungal strains (Mucor indicus, Mucor hiemalis, and Rhizopus oryzae) for xylanase production on wheat bran by SSF was investigated. Materials and methods: The effects of cultivation temperature, medium moisture content, and cultivation time on the enzyme production were investigated. Experiments were designed with an orthogonal central composite design on three variables using response surface methodology (RSM). Analysis of variance was applied and the enzyme production was expressed with a mathematical equation as a function of the three factors. The optimum operating conditions for the enzyme production was obtained. Results: For xylanase production by M. indicus, M. hiemalis and R. oryzae the optimum temperatures were 40.0, 43.4 and 43.4ºC respectively. These values were 49.8, 54.2 and 71.8% for moisture percent and 51.3, 53.2 and 53.5 h for cultivation time. The highest enzyme activities per g of dry substrate (gds) were 43.1, 43.8 and 25.9 U/gds for M. indicus, M. hiemalis and R. oryzae respectively. Discussion and conclusion: All the fungi were able to produce xylanase. Maximum xylanase production was predicted by M. indicus and M. hiemalis at similar optimum conditions, while R. oryzae produced relatively lower xylanase activity even at the best condition.

Background and Objectives: Cellulase is an important enzyme with multiple applications in industries, including food, laundry, pharmaceutical, textile, pulp, paper and biofuel industries. Solid-state fermentation (SSF) is a method for cellulase production, which includes several advantages, compared to submerged fermentation. In this study, cellulase was produced by three filamentous fungi, i.e., Mucor indicus, M. hiemalis and Rhizopus oryzae, through SSF on wheat brans. Materials and Methods: Effects of cultivation time, temperature, and moisture content of the culture media on cellulase production were investigated using response surface methodology (RSM). Experiments were carried out using an orthogonal central composite design. Based on the analysis of variance, a quadratic model was suggested as a function of the three variables to express cellulase production. The optimum parameters for cellulase production by the fungi were achieved and the highest cellulase activity was reported. Results: The fungi produced significant amounts of cellulase. Models fitted to the experimental activities of the fungi included high regression coefficients. The optimum media temperature for all fungi was 26.6 °C. For M. indicus and R. oryzae, the optimum moisture content and cultivation time of the media were 71.8% and 33.2 h, respectively. These parameters were respectively reported as 38.18% and 66.81 h for M. hiemalis. The highest cellulase activities by R. oryzae, M. indicus and M. hiemalis were 281, 163 and 188 U per g of dry wheat bran, respectively. The maximum enzyme production was seen in R. oryzae. Conclusions: In conclusion, these three advantageous fungal strains can successfully be used for cellulase production through SSF with relatively high yields, compared to other fungal strains. [ABSTRACT FROM AUTHOR]

Distiller's grains, an important commodity in the feed and food chains, are currently underdosed in rations due to several factors, mainly nutrient imbalance. This study aimed to increase the linoleic acid content in distiller's grains and decrease the excess nutrients in stillage water by the use of an artificial lichen, composed of fungi, algae, and a supporting matrix. A maximum concentration of 46.25% of linoleic acid in distiller's grains was achieved with a combination of Mucor indicus and Chlorella vulgaris using corn-to-ethanol whole stillage as substrate. Microbial hydrolytic enzymes during fermentation were able to decrease the solids in whole stillage. Nitrogen depletion by microalgal uptake causes lipid-formation stress to Mucor indicus cells, increasing linoleic acid production to about 49% of the total lipids, potentially decreasing costs in the animal feed. The culture supernatant can potentially be recycled as process water to the ethanol fermentation tank, and enhanced distiller's grains can replace animal-specific diets. This would reduce exogenous enzyme use and supplementation of unsaturated fatty acids from other sources. [ABSTRACT FROM AUTHOR]

The aim of this study was to convert the spent liquors obtained from acidic sulfite and neutral sulfite semi-chemical (NSSC) pulping processes into protein-rich fungal biomass. Three filamentous fungi, Aspergillus oryzae, Mucor indicus, and Rhizopus oryzae, were cultivated on the diluted spent liquors in an airlift bioreactor with airflow of 0.85 vvm at 35 °C and pH 5.5. Maximum values of 10.17 g, 6.14 g, and 5.47 g of biomass per liter of spent liquor were achieved in the cultivation of A. oryzae, M. indicus, and R. oryzae on the spent sulfite liquor (SSL) diluted to 60%, respectively, while A. oryzae cultivation on the spent NSSC liquor (SNL) diluted to 50% resulted in the production of 3.27 g biomass per liter SNL. The fungal biomasses contained 407 g to 477 g of protein, 31 g to 114 g of fat, 56 g to 89 g of ash, and 297 g to 384 g of alkali-insoluble material (AIM) per kg of dry biomass. The amino acids, fatty acids, and mineral elements composition of the fungal biomasses corresponded to the composition of commercial protein sources especially soybean meal. Among the fungi examined, A. oryzae showed better performance to produce protein-rich fungal biomass during cultivation in the spent liquors. [ABSTRACT FROM AUTHOR]

Kitchen and garden wastes were used for ethanol production and the residue was applied for biogas production. The wastes were pretreated with dilute acid to improve the yield of ethanol production. The pretreatments were carried out with 0.05 M sulfuric acid at 120, 150, and 180 °C for 0, 10, 30, and 60 min, resulting in a liquor mainly containing starchy materials and hemicellulosic sugars and a solid mainly containing cellulose. In order to remove the inhibitors from the liquor, a detoxification step with lime (overliming) was performed. Furthermore, the starch contents of the liquor were enzymatically hydrolyzed before fermentation. Then, the liquor was fermented with ethanolic fungus Mucor indicus , which is a highly inhibitor-tolerant strain of Zygomycetes . After that, the biomasses obtained from aerobic and anaerobic fermentation along with the dilute acid–pretreated solids were subjected to anaerobic digestion for biogas production. The results showed that the addition of fermentation biomass to the pretreated solid significantly improved the biomethane production yield. After pretreatment at 150 °C for 30 min and without detoxification, the maximum amounts of gasoline equivalent of 162.1 and 120.6 L were obtained with and without starch hydrolysis, respectively, where methane production yield was 157.4 mL/g VS and ethanol yields were 75.9% and 94.2%. [ABSTRACT FROM AUTHOR]

Two different morphologies of fungus Mucor indicus were used for the biosorption of copper ions from aqueous solutions. Potentiometric titration, chemical modification of functional groups, and Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analyses were performed to characterize the biosorption process. The presence of carboxyl, phosphate, and amine functional groups on the biomass of both morphologies was indicated by potentiometric titration and FTIR analysis. Chemical modification of carboxyl and amine groups showed that these groups considerably affected the biosorption, while the extraction of lipids did not influence the process. Ions of Na+, K+, Ca2+, and Mg2+ were released into the solution during copper adsorption, indicating that ion exchange was a key mechanism in the biosorption. Copper removal was accompanied by the adsorption of hydrogen ions on the filamentous form biomass; however, it was complemented with the release of hydrogen ions from the yeast-like biomass. Kinetics and isotherm data were appropriately fitted to Ho and Langmuir models, respectively. Maximum adsorption capacity predicted by Langmuir model for the filamentous form (24.5 mg g–1) was higher than that of the yeast-like form (14.5 mg g–1), which was attributed to the higher contents of phosphate, glucosamine, and active sites in the filamentous biomass. SEM micrographs revealed the difference between the surfaces of the two morphologies, resulting in different adsorption behaviors. [ABSTRACT FROM AUTHOR]

Dissolution of lignocelluloses in N-methylmorpholine- N-oxide (NMMO or NMO) at moderate conditions, e.g., 120 °C for 3 h under atmospheric pressure, and regeneration with water, is among the most effective nonderivatization pretreatment for the improvement of enzymatic hydrolysis and ethanol production. The effects of the pretreatment on two different types of wood, hardwood elm and softwood pine, were compared via physicochemical structural analyses, i.e., FTIR, XRD, SEM, TGA, and enzyme adsorption techniques, to relate their properties to the extent of enzymatic conversion. After the pretreatment, cellulose was highly recovered and characterized to be mainly cellulose II and amorphous cellulose, with lower cellulose crystallinity index, higher thermal stability, and more favorable surface features for hydrolysis, compared to native woods. Moreover, the strength of enzyme binding onto the lignocelluloses, which was directly related to the enzymatic hydrolysis rate, increased by 57% and 164% for pinewood and elmwood, respectively. The highest total reducing sugars yield for untreated pinewood was 9.8% (74 mg/g-substrate) and improved to 58.5% (330 mg/g-substrate) after the pretreatment, whereas the corresponding values for elmwood were 14.7% (104 mg/g-substrate) vs. 51.4% (274 mg/g-substrate). Furthermore, maximum ethanol theoretical yields of 63.5 and 41.4% were obtained from pinewood and elmwood by Saccharomyces cerevisiae and Mucor indicus, respectively. [ABSTRACT FROM AUTHOR]

The current challenge in intensive aquaculture is to control the level of nutrient pollutants in the wastewater and provide sustainable sources of proteins for feed. A synthetic lichen type biofilm was developed to have the fungus Mucor indicus and the microalga Chlorella vulgaris grow together on a polymer matrix referred to as a “mycoalgae” biofilm. When the biofilm grows, it takes up phosphorus and nitrogen compounds and converts them to proteins and other cellular products. It cleans the water from nutrient pollutants as the algae are attached to the biofilm leaving purified water at the end of the process. Under 25 mg L −1 total ammonia-N (TAN) conditions, the biofilm reduced TAN to undetectable limits within 48 h with over 69% of the TAN reduction taking place by 24 h. The biofilm reduced levels of phosphate-P from 15 mg to undetectable limits within 24 h. Under the same conditions, 860 mg of dry mycoalgae biomass was generated at the end of the process on 16 cm 2 of mesh and 100 ml of culture media. This process allows for easy harvesting of the algae with no energy intensive process of separating the algae from the supernatant. The generated biofilm is composed of two organisms that have been shown to positively aid fish health when included as a feed supplement. [ABSTRACT FROM AUTHOR]

[Display omitted] • Corn stover was processed by dilute acid pretreatment, enzymatic hydrolysis, and fermentation. • Mucor indicus were implemented as ethanol-producing and oleaginous microorganism. • The biorefinery process efficiently produced bioethanol, biodiesel, and biogas. • The biorefinery derived chitosan, animal feed, and glycerol as value-added byproducts. • Socioeconomic analysis showed a significant impact on GHG emissions reductions. The present study investigated an integrated biorefinery that employed corn stover as the feedstock for sustainable bioethanol, biodiesel, biogas, chitosan, glycerol, and animal feed production. Corn stover was initially subjected to dilute acid pretreatment (1.8 % v/v H 2 SO 4 , 121 °C, and 22 min) followed by enzymatic hydrolysis with a commercial cellulase (37 °C, 72 h) to promote the release of glucose (∼93 wt%) and xylose (∼89 wt%). Mucor indicus fungus was then employed to convert the released sugars into bioethanol, glycerol, and fungal biomass with yields of 0.38 g g−1, 36 mg g−1, and 0.51 g g−1, respectively. The biomass of M. indicus was processed to extract chitosan (6 mg g−1 fungal biomass) and lipids (297 mg g−1 fungal biomass). The lipid was subsequently converted to biodiesel via transesterification in the presence of HCl/ MeOH with the yield of 0.54 g g−1 fungal lipid. The defatted biomass residue was then converted to biogas with 81 % theoretical yield through anaerobic digestion. To ensure process circularity, the nutritional values of pretreated and hydrolyzed corn stover were also investigated with their suitability as livestock. It was determined that 158.1 thousand tons of dry corn stover, which was annually collectible in Iran, could be used for the production of 137.6 kg chitosan, 10.4 ton animal feed, 870.0 kg glycerol, 40.7 million litters ethanol, 2.8 million m3 biodiesel, and 449.2 million m3 biomethane. The utilization of the produced ethanol, biodiesel, and biomethane in transporting sector was shown to have the potential of facilitating 4.3 million tons of equivalent carbon dioxide and a 197.8 million dollars reduction of associated social costs. [ABSTRACT FROM AUTHOR]

Distiller’s grains, an important commodity in the feed and food chains, are currently underdosed in rations due to several factors, mainly nutrient imbalance. This study aimed to increase the linoleic acid content in distiller’s grains and decrease the excess nutrients in stillage water by the use of an artificial lichen, composed of fungi, algae, and a supporting matrix. A maximum concentration of 46.25% of linoleic acid in distiller’s grains was achieved with a combination of Mucor indicus and Chlorella vulgaris using corn-to-ethanol whole stillage as substrate. Microbial hydrolytic enzymes during fermentation were able to decrease the solids in whole stillage. Nitrogen depletion by microalgal uptake causes lipid-formation stress to Mucor indicus cells, increasing linoleic acid production to about 49% of the total lipids, potentially decreasing costs in the animal feed. The culture supernatant can potentially be recycled as process water to the ethanol fermentation tank, and enhanced distiller’s grains can replace animal-specific diets. This would reduce exogenous enzyme use and supplementation of unsaturated fatty acids from other sources.

The current challenge in intensive aquaculture is to control the level of nutrient pollutants in the wastewater and provide sustainable sources of proteins for feed. A novel lichen type biofilm was developed, comprised of a fungus, Mucor indicus , and a microalga, Chlorella vulgaris , growing symbiotically on a polymer matrix termed a "mycoalgae biofilm". Previous studies established that the mycoalgae biofilm can reduce ammonia levels in synthetic aquaculture wastewater. In this study, different cultivation conditions as relate to various forms of aquaculture wastewater were studied, including glucose, ammonia concentrations, and process time, in a central composite design experiment. Growing Chlorella vulgaris and Mucor indicus in simulated aquaculture wastewater reduced levels of ammonia while producing an easily harvestable mycoalgae biomass which is possible for fish feeds. Experimental results showed that the biofilm readily formed over a range of ammonia conditions (6.14 mg L−1 to 124 mg L−1) albeit with varying algae to fungi compositions (14.8 % to 0.5 % algae composition of the biofilm). Glucose concentration was the strongest predictor of significant ammonia removal, with time being a non-significant variable over the range of values tested (56 h to 136 h) indicating a shorter process duration as acceptable. Amino acid quantities in the mycoalgae biomass align with simple additive values of amino acids present in the algae and fungi alone. The mycoalgae biofilm was confirmed to grow in actual aquaculture wastewater both sterilized and unprocessed. These continued studies demonstrated the efficacy of the biofilm under a wide range of aquaculture conditions thus confirming its application in real aquaculture wastewater. [Display omitted] • A novel mycoalgae biofilm for wastewater treatment was developed. • It was formed by filamentous fungus co-grows with microalgae on synthetic matrix. • The biofilm is featured for easy harvest of cell biomass. • Mycoalgae biofilm can effectively remove nitrogen pollutant from wastewater. • Mycoalgae is rich in key amino acids with potential for aquaculture feed supply. [ABSTRACT FROM AUTHOR]

In a novel valorization approach for simultaneous pectin extraction and pretreatment (SPEP) of citrus waste (CW) by dilute nitric acid and ethanol, almost all of the CW was converted to bio-derived chemicals in a singlestep process at a low/moderate temperature. The SPEP was performed at different temperatures (70 °C and 80 °C), pH (1.8, 3.0, and 4.3), and extraction times (2 h and 3 h) with a full factorial design. The maximum pectin yield of 45.5% was obtained at pH 1.8, 80 °C, and 2 h. The pectin yields at pH 1.8 were much higher than at pH 4.3 and 3. Also, the degree of methyl-esterification at pH 1.8 was higher than 50%, whereas at the higher pH, low methoxyl pectins were extracted. The treated CW obtained after the SPEP, free from limonene, was subjected to separate cellulolytic enzymatic hydrolysis and ethanolic fermentation. The glucose yields in the enzymatic hydrolysates were higher for the CW treated at pH 1.8. The fermentation of the enzymatic hydrolysates by Mucor indicus resulted in fungal biomass yields in the range of 355 to 687 mg per g of consumed sugars. The optimum conditions for obtaining the maximum SPEP yield (glucose + pectin (g) / raw material (g))*100) were pH 1.8, 80 °C, and 2 h, which resulted in a yield of 58.7% (g/g CW). [ABSTRACT FROM AUTHOR]

In this study the effects of phosphate, potassium, yeast extract, and trace metals on the growth of Mucor indicus and chitosan, chitin, and metabolite production by the fungus were investigated. Maximum yield of chitosan (0.32 g/g cell wall) was obtained in a phosphate-free medium. Reversely, cell growth and ethanol formation by the fungus were positively affected in the presence of phosphate. In a phosphate-free medium, the highest chitosan content (0.42 g/g cell wall) and cell growth (0.66 g/g sugar) were obtained at 2.5 g/L of KOH. Potassium concentration had no significant effect on ethanol and glycerol yields. The presence of trace metals significantly increased the chitosan yield at an optimal phosphate and potassium concentration (0.50 g/g cell wall). By contrast, production of ethanol by the fungus was negatively affected (0.33 g/g sugars). A remarkable increase in chitin and decrease in chitosan were observed in the absence of yeast extract and concentrations lower than 2 g/L. The maximum chitosan yield of 51% cell wall was obtained at 5 g/L of yeast extract when the medium contained no phosphate, 2.5 g/L KOH, and 1 mL/L trace metal solution. [ABSTRACT FROM AUTHOR]

Objective: Glucoamylase is a hydrolyzing enzyme with several industrial applications. Glucoamylase was produced via a solid state fermentation by three naturally occurring zygomycetes fungi of Mucor indicus, Mucor hiemalis, and Rhizopus oryzae on wheat bran. Methods: The effects of cultivation temperature, medium moisture content, and cultivation time on the enzyme production were investigated. Experiments were designed with an orthogonal central composite design on the three variables using response surface methodology (RSM). Results: For glucoamylase production, the optimum temperature and medium moisture content for the three fungi were 26.6°C and 71.8%, respectively. The optimum cultivation time for M. hiemalis and R. oryzae was 33.1 h, while it was 66.8 h for M. indicus. At optimum conditions, glucoamylase production by M. indicus, M. hiemalis, and R. oryzae was respectively 255.3, 272.3, and 1545.3 U per g dry substrate. Conclusion: R. oryzae is a suitable candidate for industrial production of glucoamylase. [ABSTRACT FROM AUTHOR]

BACKGROUND Mucor indicus is a dimorphic fungus capable of producing ethanol, with numerous advantages compared with Saccharomyces cerevisiae. RESULTS Cellulose solvent- and organic solvent-based lignocellulosic fractionation ( COSLIF) enhanced the enzymatic hydrolysis yield and especially the initial hydrolysis rate. Effects of the fungal morphology on the major metabolites, i.e., ethanol and biomass ingredients (fatty acids and chitosan) were investigated. Purely yeast-like form yielded 78-92% of the maximum theoretical ethanol yield with 0.43-0.64 g L−1 h−1 productivity, whereas fermentation by purely filamentous form resulted in the yield and productivity of 48-66% and 0.3-0.4 g L−1 h−1, respectively. Beside ethanol, the fungus produced a large amount of chitin-chitosan (62-67% of the fungal alkali insoluble materials) in filamentous form, while the value was 41-45% for yeast-like form. Furthermore, yeast-like cells produced nutritionally valuable fatty acids at a rate higher than that by filamentous form (3.7 and 2.7%, respectively). Linoleic acid, a polyunsaturated omega-6, was the dominant fatty acid available in the biomass with both morphologies. CONCLUSIONS The fermentation products were significantly dependent on the fungus morphology but not on the lignocellulose type. Yeast-like cells exhibited better performance in ethanol and oil production, whereas the filamentous cells produced higher amounts of chitosan. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Oil palm empty fruit bunch (OPEFB) is a potential raw material for production of lignocellulosic bioethanol. The OPEFB was pretreated with 8% sodium hydroxide (NaOH) solution at 100°C for 10 to 90 min. Enzymatic digestion was carried out using cellulase and β-glucosidase at 45°C for 24 h. It was then inoculated withMucor indicusspores suspension and fermented under anaerobic conditions at 37°C for 96 h. Sodium hydroxide pretreatment effectively removed 51–57% of lignin in the OPEFB and also its hemicellulose (40–84%). The highest glucan digestibility (0.75 g/g theoretical glucose) was achieved in 40-min NaOH pretreatment. Fermentation byM. indicusresulted in 68.4% of the theoretical ethanol yield, while glycerol (16.2–83.2 mg/g), succinic acid (0–0.4 mg/g), and acetic acid (0–0.9 mg/g) were its by-products. According to these results, 11.75 million tons of dry OPEFB in Indonesia can be converted into 1.5 billion liters of ethanol per year. [ABSTRACT FROM AUTHOR]

This paper presents an in-depth exergy analysis of the ethanol fermentation process with various forms of fungus Mucor indicus under aerobic and anaerobic conditions to select the most productive and sustainable conditions. Various carbon sources including fructose, glucose, and sucrose as well as the whole and inverted sugar beet and sugarcanes molasses were used during the fermentation. The rational and process exergetic efficiencies were found to be in the range of 65.21%–88.54% and 0.00%–44.31%, respectively. Overall, the exergy-based parameter based on the process outputs could provide useful information about the sustainability and productivity of the fermentation process compared to the rational analysis. More specifically, the inverted sugar beet molasses with MF (mostly filamentous) form of M. indicus under anaerobic cultivation was shown to be the best option for industrial production phase with respect to the productivity and sustainability issues. The results obtained confirmed that the process yield alone cannot perfectly reflect the exact sustainability parameters of the renewable ethanol production systems. Finally, the developed exergetic framework could help engineers to couple biochemical and physical concepts more robustly for achieving the most cost-effective and eco-friendly pathways for bioethanol production. [ABSTRACT FROM AUTHOR]

The potential of two zygomycetes fungi, Mucor indicus and Rhizopus oryzae, in assimilating citrus waste free sugars (CWFS) and producing fungal chitosan, oil, and protein as well as ethanol was investigated. Extraction of free sugars from citrus waste can reduce its environmental impact by decreasing the possibility of wild microorganisms growth and formation of bad odors, a typical problem facing the citrus industries. A total sugar concentration of 25.1 g/L was obtained by water extraction of citrus waste at room temperature, used for fungal cultivation in shake flasks and airlift bioreactor with no additional nutrients. In shake flasks cultivations, the fungi were only able to assimilate glucose, while fructose remained almost intact. In contrast, the cultivation of M. indicus and R. oryzae in the four-liter airlift bioreactor resulted in the consumption of almost all sugars and production of 250 and 280 g fungal biomass per kg of consumed sugar, respectively. These biomasses correspondingly contained 40% and 51% protein and 9.8% and 4.4% oil. Furthermore, the fungal cell walls, obtained after removing the alkali soluble fraction of the fungi, contained 0.61 and 0.69 g chitin and chitosan per g of cell wall for M. indicus and R. oryzae, respectively. Moreover, the maximum ethanol yield of 36% and 18% was obtained from M. indicus and R. oryzae, respectively. Furthermore, that M. indicus grew as clump mycelia in the airlift bioreactor, while R. oryzae formed spherical suspended pellets, is a promising feature towards industrialization of the process. [ABSTRACT FROM AUTHOR]

Introduction: Xylan is the main hemicellulosic polymer in a number of lignocelluloses which can be hydrolyzed by xylanolytic enzymes. One of the main ways for enzymes production is solid state fermentation (SSF). The ability of three fungal strains (Mucor indicus, Mucor hiemalis, and Rhizopus oryzae) for xylanase production on wheat bran by SSF was investigated. Materials and methods: The effects of cultivation temperature, medium moisture content, and cultivation time on the enzyme production were investigated. Experiments were designed with an orthogonal central composite design on three variables using response surface methodology (RSM). Analysis of variance was applied and the enzyme production was expressed with a mathematical equation as a function of the three factors. The optimum operating conditions for the enzyme production was obtained. Results: For xylanase production by M. indicus, M. hiemalis and R. oryzae the optimum temperatures were 40.0, 43.4 and 43.4ºC respectively. These values were 49.8, 54.2 and 71.8% for moisture percent and 51.3, 53.2 and 53.5 h for cultivation time. The highest enzyme activities per g of dry substrate (gds) were 43.1, 43.8 and 25.9 U/gds for M. indicus, M. hiemalis and R. oryzae respectively. Discussion and conclusion: All the fungi were able to produce xylanase. Maximum xylanase production was predicted by M. indicus and M. hiemalis at similar optimum conditions, while R. oryzae produced relatively lower xylanase activity even at the best condition. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of indole-3-acetic acid (IAA) and kinetin (KIN) on Mucor indicus growth, cell wall composition, and ethanol production. A semi-synthetic medium, supplemented with 0-5 mg/L hormones, was used for the cultivations (at 32 °C for 48 h). By addition of 1 mg/L of each hormone, the biomass and ethanol yields were increased and decreased, respectively. At higher levels, however, an inverse trend was observed. The glucosamine fraction of the cell wall, as a representative for chitosan, followed similar but sharper changes, compared to the biomass. The highest level was 221% higher than that obtained without hormones. The sum of glucosamine and N-acetyl glucosamine (chitin and chitosan) was noticeably enhanced in the presence of the hormones. Increase of chitosan was accompanied by a decrease in the phosphate content, with the lowest phosphate (0.01 g/g cell wall) being obtained when the chitosan was at the maximum (0.45 g/g cell wall). In conclusion, IAA and KIN significantly enhanced the M. indicus growth and chitosan production, while at the same time decreasing the ethanol yield to some extent. This study shows that plant growth hormones have a high potential for the improvement of fungal chitosan production by M. indicus. [ABSTRACT FROM AUTHOR]

Chitosan purified fromMucor indicusbiomass as well as the biomass and its derivatives including cell wall and the residues remaining after chitosan extraction were evaluated for copper removal from aqueous solutions. Chitosan was extracted using hydrochloric and acetic acids. The acid type did not affect the adsorption capacities of the chitosans and the corresponding cell wall residues, while the rate of biosorption by the adsorbents produced using acetic acid was higher than those produced using hydrochloric acid. Pseudo-second-order model described the kinetics data appropriately. The highest level of the maximum adsorption capacities predicted by Langmuir model was found for the cell wall (84 mg/g) and the chitosans (81 mg/g), whereas the lowest level was observed for the cell wall residues (about 3 mg/g). Scanning electron microscopy micrographs showed modification of the absorbents surfaces, resulting in different adsorption behaviors. FTIR analysis identified the involvement of different functional groups for copper removal. [ABSTRACT FROM AUTHOR]