The essential role of spontaneous and starter yeasts in cocoa and coffee fermentation.

Yeasts are important microorganisms used in different fermentation processes. The cocoa beans must go through a correct fermentation process to obtain good-quality chocolate, which involves the action of yeasts and bacteria, and yeasts play a crucial role since they act in the first days of fermentation. In coffee, several studies have shown that the microbiota in the fruits is also a relevant factor. The fermentation process (regardless of the processing type) improves the beverage's quality. In this sense, studies using starter cultures in these two raw materials are important for better control of the process, and optimization of fermentation time, in addition to the improvement and diversification of volatile and non-volatile compounds produced by yeasts. Thus, this review discusses the importance and role of yeasts during fermentation, their metabolism, the produced compounds, and how yeast and the different chemical reactions help increase the quality of chocolate and coffee.

Revealing the microbial diversity and physicochemical characteristics of Brazilian untreated green table olives.

AIM: This work evaluated the microbial diversity and physicochemical characteristics of fresh and fermented fruits from Brazilian untreated green table olives of the Ascolano and Grappolo cultivars. METHODS AND RESULTS: Twenty species of mesophilic bacteria, seven lactic acid bacteria, and fourteen yeast were identified. Some species prevailed over others, such as the bacteria Levilactobacillus brevis, Lacticaseibacillus paracasei subsp. paracasei, Pantoea agglomerans, Staphylococcus warneri, Bacillus simplex, B. thuringiensis, and the yeasts Candida parapsilosis, Ca. orthopsilosis, and Cryptococcus flavescen. In the olive fruit and olive brine, the sugars: sucrose, glucose, mannitol, and fructose, and the acids: acetic, citric, lactic, malic, and succinic were identified. Thirty-seven volatile compounds belonging to different chemical classes of acids, alcohols, aldehydes, esters, hydrocarbons, phenols, ketones, and ether were identified in the fruits and brine olives. CONCLUSION: The polyphasic methodology using matrix assisted laser desorption/ionization-time of flight and 16S rRNA sequencing was efficiently performed to identify microorganisms; chemical analysis helped to understand the fermentation process of olives.

Wet fermentation of Coffea canephora by lactic acid bacteria and yeasts using the self-induced anaerobic fermentation (SIAF) method enhances the coffee quality.

This work aimed to evaluate the impact of inoculation single and co-cultivation of LAB and yeasts during the wet process of Coffea canephora using the self-induced anaerobic fermentation method. Saccharomyces cerevisiae, Totulaspora delbrueckii delbrueckii, Leuconostoc mesenteroides, and Lactiplantibacillus plantarum were monitored during fermentation. L. mesenteroides was detected in high concentrations in the coffee fruits (8.54 log10 cells/mL) and remained until the end of fermentation. Lactic and acetic acids were the main acids produced during fermentation. After 36 h of fermentation, 75.39% of malic acid was consumed in the L. mesenteroides + S. cerevisiae (MC) fermentations. In roasted coffee, the caffeine concentration reached 3.29 higher than the green beans in MC fermentation. Specific volatile compounds were detected in inoculated fermentation and may contribute to the beverage quality. Coffee inoculated with Leuconostoc mesenteroides was classified as fine (80.0-89.0), while the other fermentations were classified as premium (70.0-79.0). L. mesenteroides inoculation showed the best sensory score, and the beverage was characterized by caramel, fruity, and spices notes. L. mesenteroides inoculated alone or in co-culture with S. cerevisiae are promising starter cultures to improve Conilon coffee quality and obtain beverages with differentiated sensory profiles.

Volatile compounds for biotechnological applications produced during competitive interactions between yeasts and fungi.

Fungi, yeasts and bacteria produce volatile compounds during their metabolism. In this study, the volatile compounds produced by yeast strains (Saccharomyces cerevisiae and Rhodotorula mucilaginosa) and fungal strains (Aspergillus carbonarius and Aspergillus ochraceus) during competitive interactions were investigated by solid-phase microextraction coupled with gas chromatography-mass spectrometry. Fifty-six volatile compounds were identified representing alcohols, aldehydes, esters, ketones, aromatic compounds, acids, furans, phenols, and nitrogen compounds, being the largest amount in the class of esters and alcohols. Eight compounds were identified only in interactive culture conditions such as 2-amino-1-propanol, isopropylamine, dimethylamine, pentyl propanoate, ethyl-2-aminopropanoate, acetone, oxalic acid, and ß-elemene and five of these were produced in cocultures including A. carbonarius. These will be developed for future biotechnological applications such as in the pharmaceutical and biological industry to produce drugs. Antimicrobial and antifungal activities; Solvent and herbicide; flavoring ingredient; solvent, plastic synthesis, nail polish remover and thinner, pesticide and herbicide; important in the complexation of minerals in the soil; and plant-environment interactions, defending predators, pathogens, and competitors.

Impact of lead (Pb2+) on the growth and biological activity of Serratia marcescens selected for wastewater treatment and identification of its zntR gene-a metal efflux regulator.

Microorganisms isolated from contaminated areas play an important role in bioremediation processes. They promote heavy metal removal from the environment by adsorbing ions onto the cell wall surface, accumulating them inside the cells, or reducing, complexing, or precipitating these substances in the environment. Microorganism-based bioremediation processes can be highly efficient, low-cost and have low environmental impact. Thus, the present study aimed to select Pb2+-resistant bacteria and evaluate the growth rate, biological activity, and the presence of genes associated with metal resistance. Serratia marcescens CCMA 1010, that was previously isolated from coffee processing wastewater, was selected since was able to growth in Pb2+ concentrations of up to 4.0 mM. The growth rate and generation time did not differ from those of the control (without Pb2+), although biological activity decreased in the first hour of exposure to these ions and stabilized after this period. The presence of the zntR, zntA and pbrA genes was analysed, and only zntR was detected. The zntR gene encodes a protein responsible for regulating the production of ZntA, a transmembrane protein that facilitates Pb2+ extrusion out of the cell. S. marcescens CCMA 1010 demonstrated a potential for use as bioindicator that has potential to be used in bioremediation processes due to its resistance to high concentrations of Pb2+, ability to grow until 24 h of exposure, and possession of a gene that indicates the existence of mechanisms associated with resistance to lead (Pb2+).

Self-induced anaerobiosis coffee fermentation: Impact on microbial communities, chemical composition and sensory quality of coffee.

Microbial communities associated with coffee fermentation have been widely investigated. However, few reports about self-induced anaerobiosis fermentation (SIAF) on microbial diversity and the chemical and sensory profile of coffees grown under different environmental conditions have been studied. This study evaluated the microbial, chemical, and sensorial profile of the natural and pulped coffee fermented with and without induced anaerobiosis. The microbial diversity was determined by plating and next-generation sequencing, the chemical profile through 1H NMR and chemometrics analysis, and sensory analysis was conducted by Temporal Dominance of Sensations (TDS). Three hundred and eighty microorganisms were isolated; 149 mesophilic bacteria, 147 lactic acid bacteria, and 84 yeasts. Hanseniaspora uvarum, Lactiplantibacillus plantarum, Leuconostoc mesenteroides, and Weissella cibaria were identified in Monte Carmelo, Três Pontas, Carmo de Minas, and Lajinha in Minas Gerais, Brazil. New generation sequencing (NGS) analysis identified a high yeast species diversity (74). Some metabolites such as chlorogenic acid, sucrose, lactic acid, and trigonelline were identified in fermented coffees with the joint analysis of NMR and the loadings of PC1. Monte Carmelo coffees processed by the pulped method stood out sensorially showed a higher dominance rate for woody, herbaceous and fruity attributes. The SIAF positively impacts microbial behavior, resulting in coffees with a more intensified fruity attribute.

Chemical and sensory characterization of coffee from Coffea arabica cv. Mundo Novo and cv. Catuai Vermelho obtained by four different post-harvest processing methods.

BACKGROUND: After the harvest, green coffee beans are dried on the farm using several methods: the wet process, natural process, pulped natural process, or mechanical demucilaging. This study evaluated how the choice of a specific processing method influenced the volatile organic compounds of the coffee beans, before and after roasting, and the sensory characteristics of the beverage. Coffea arabica beans of two varieties (cv. Mundo Novo and cv. Catuai Vermelho) were subjected to these four processing methods on a single farm in the Cerrado area of Brazil. RESULTS: Analysis by gas chromatography-mass spectrometry headspace solid-phase microextraction identified 40 volatile organic compounds in green coffee beans and 37 in roasted beans. The main difference between post-harvest treatments was that naturally processed green beans of both varieties contained a different profile of alcohols, acids, and lactones. In medium-roasted beans, those differences were not observed. The coffee beverages had similar taste attributes but distinct flavor profiles. Some of the treatments resulted in specialty-grade coffee, whereas others did not. CONCLUSION: The choice of a specific post-harvest processing method influences the volatile compounds found in green beans, the final beverage's flavor profile, and the cupping score, which can have a significant impact on the profitability of coffee farms' operations. © 2022 Society of Chemical Industry.

Fermentation of Coffea canephora inoculated with yeasts: Microbiological, chemical, and sensory characteristics.

This work aimed to evaluate Coffea canephora's microbiological, chemical, and sensory characteristics at 300 and 600 m elevation plantations processed by the natural method inoculated with yeasts. The coffee was spread on suspended terraces and sprayed with approximately 107 cfu/mL of Meyerozyma caribbica CCMA 1738 or Pichia kluyveri CCMA 1743, separately. Cherries containing bark and parchment were collected during fermentation for microbial groups counting, qPCR, quantification of organic acids, and sugars (HPLC). Volatile compounds (GC-MS) and sensory analyses, cupping test with expert coffee tasters and triangular test with consumers, were performed on roasted coffee beans. The inoculated yeasts persisted during the entire fermentation process. M. caribbica reduced the filamentous fungal population by 63% and 90% in the 300- and 600-m coffees, respectively. The 300-m coffee fruits showed higher concentrations of organic acids in all fermentation times when compared to the 600-m reaching out to 8 times more. Twenty-four volatile compounds were identified in the roasted coffee beans, with the predominance of pyrazines. The 600-m coffee inoculated with M. caribbica showed an increase of more than one point in the score given by certified tasters. Consumers noticed the M. caribbica inoculation in the 300- and 600-m-elevation coffees. M. caribbica is a promising starter culture for Conilon coffee with the potential to increase the beverage quality.

Bio-hydrolysis of used soybean oil: environmental-friendly technology using microbial consortium.

In this work, strains of Bacillus subtilis were inoculated in consortium with Rhodotorula mucilaginosa into spent soy oil as aiming to biological treatment and low-cost reuse. The microorganisms were previously isolated and selected for the lipolytic capacity of the alperujo residue generated during the processing of olive oil. For fermentation, bioassays containing Rhodotorula mucilaginosa isolated from alperujo and Candida rugosa CCMA 00371, both co-inoculated with Bacillus subtilis CCMA 0085 in medium containing (% w/v) 0.075 glucose and 0.375 (NH4)3 PO4 in 75 mL of water and 75 mL of spent soy oil. Despite the low biomass productivity, it has favorable characteristics to be used in animal feed supplementation. Spent soy oil was used as a carbon source proven by Bartha respirometer. The strains of R. mucilaginosa UFLA RAS 144 and B. subtilis CCMA 0085 are promising inoculants for oil degradation and can be applied in a waste treatment system.

Heat stress influence the microbiota and organic acids concentration in beef cattle rumen.

The objective of this study was to evaluate the effect of heat stress on meta-taxonomic and metabolic profiles of prokaryotes in beef cattle rumen. Six pure-breed Nellore heifers with ruminal cannulas were used in the study. Six treatments were tested in a 6 × 6 Latin Square with six periods of 21days. The treatments were evaluated in a 2 × 2 + 2 factorial arrangement, consisting of 4 combinations: two temperatures conditions (thermoneutral, TN: 24 °C; and heat stress, HS: 34 °C) and two dietary energy concentration [low-energy (37% non-fibrous carbohydrates - NFC, 12 Mcal of metabolizable energy per kg of dry matter) or high-energy concentration (50.5% NFC, 18.49 Mcal of metabolizable energy per kg of dry matter)] plus two additional treatments with animals maintained in TN conditions but with your intake restricted (TN-RI) to the same of the heifers in HS with the two dietary energy concentration. The meta-genome was sequenced by MiSeq Sequencing System platform, and the DNA sequences were analysed using Geneious 10.2.3 software. The metabolic profile was evaluated by liquid and gas chromatography. Animals under HS presented lower (P = 0.04) prokaryote richness than animals under TN conditions. The genera Flavonifractor (1.4%), Treponema (0.6%) and Ruminococcus (0.9%) showed the lowest (P < 0.04) and Carnobacterium (7.7%) the highest (P = 0.02) relative abundance when the animals were submitted to HS, in relation to animals in TN. A total of 49 different metabolites were identified in the ruminal samples. The concentration of isobutyric acid (4.32 mM) was highest in bovine rumen under HS conditions. Heat stress influenced the microbiota and concentration of some organic acids in beef cattle rumen. There was a reduction in the richness of rumen in cattle under heat stress, but the diversity of prokaryotes was not affected.

Protocol to select efficient microorganisms to treat coffee wastewater.

The coffee processing wastewater (CPWW) requires treatment before being disposed of in the environment or reused due to its high organic and inorganic composition and a low pH. The indigenous microbiota from CPWW is highly diverse and could be selected as inoculums in treatment waste plants. Considering the physico-chemical characteristics of wastewater coffee, we elaborate on steps to select the microbial consortium that showed positive impact via decreasing the pollutant parameters of this effluent. The effectiveness was confirmed using wastewater from different origins with different chemical characteristics. A bacterial consortium composed by Serratia marcescens CCMA 1010 and CCMA 1012, Corynebacterium flavescens CCMA 1006, and Acetobacter indonesiensis CCMA 1002 was selected as the inoculums-based phenotypic assays. The mixed inoculum showed a highly active population (11.18 log CFU mL-1), promoting an 85% decrease in biochemical oxygen demand and a 60% decrease in chemical oxygen demand. There was also an 80% reduction in phosphorus and nitrogen. The final pH changed from 6.0 to 7.5. Additionally, the eco-toxicity using Daphnia similis was reduced by more than 59%. The microbial inoculum was efficient in the biological treatment in CPWWs, demonstrating the efficiency and robustness of the selected strains, independent of the physico-chemical characteristics of wastewater.

Microbial diversity and chemical characteristics of Coffea canephora grown in different environments and processed by dry method.

This study aimed to assess the microbial diversity in Coffea canephora grown in four different environments of Espirito Santo state, Brazil. Coffee cherries of two different altitudes (300 and 600 m) and two terrain aspects (Southeast-facing and Northwest-facing slopes) were processed by the dry method. Samples were collected during the drying/fermentation process. Microorganisms were counted, isolated, and identified by MALDI-TOF, followed by sequencing of the ribosomal region. Sugars and organic acids were quantified by HPLC and volatile compounds of the roasted coffees were evaluated by GC-MS. Bacteria population presented a significant number of isolates as well as higher counts during the drying/fermentation process with respect to the population of yeasts. The principal genera of microorganisms found were Bacillus, Pichia, Candida, and Meyerozyma. Meyerozyma guilliermondii was the most frequent yeast in all environments. On the other hand, Pichia kluyveri was found only in coffee cherries from the 600 m altitude. The highest concentration of acetic and succinic acids observed was 6.06 mg/g and 0.84 mg/g, respectively. Sucrose concentrations ranged from 0.68 to 5.30 mg/g, fructose from 1.30 to 4.60 mg/g, and glucose from 0.24 to 1.25 mg/g. Thirty-six volatile compounds, belonging to the groups of pyrazines, alcohols, aldehydes, ketones, and furans were identified in roasted coffee, with differences between altitude and terrain aspects. Information about microbial diversity is crucial to better understand the coffee quality and distinct characteristics of coffee produced in different environments.

Yeasts isolated from Brazilian fermented foods in the protection against infection by pathogenic food bacteria.

The consumption of probiotics has increased due to the reported health benefits, mainly in preventing or treating gastrointestinal pathology. This study investigated the antimicrobial capacity of yeasts, Saccharomyces cerevisiae and Pichia kluyveri, previously isolated from fermented foods (indigenous beverage, kefir and cocoa) against the adhesion of foodborne pathogens to Caco-2 cells. Co-aggregation of yeasts with pathogens and were evaluated by quantitative analysis and using scanning electron and laser confocal microscopies. All yeasts strains were able to co-aggregate with the tested pathogens, however, this activity was strain-dependent. The inhibition tests showed that the adhesion of Escherichia coli EPEC, Listeria monocytogenes and Salmonella Enteritidis to Caco-2 was reduced by all the yeasts studied. Most of the evaluated yeasts showed inhibition rates equal to or greater than the commercial probiotic Saccharomyces boulardii. The yeasts were able to reduce up to 50% of the bacterial infection, as observed for CCMA0615 towards EPEC in exclusion assay; CCMA0731, CCMA0732 and CCMA0615 towards L. monocytogenes in exclusion and competition assays; and CCMA0731 in exclusion and CCMA0731, CCMA0732, CCMA0615 in competition assay towards S. Enteritidis. No antimicrobial compounds were produced by the yeasts, showing that competition for nutrients and/or receptors in the intestinal mucosa was the mechanism to bacterial inhibition.

The use of mesophilic and lactic acid bacteria strains as starter cultures for improvement of coffee beans wet fermentation.

The use of starter cultures during food fermentation aims to standardize the process and to obtain a higher quality product. The objectives were to study mesophilic bacteria (MB) and lactic acid bacteria (LAB) isolated from wet coffee processing and evaluate their performance in a pulped coffee medium. Eighty-six bacteria isolates (59 MB and 27 LAB) were assessed for pectinolytic activity, metabolite production, and pH value decrease in coffee-based culture (CPM). Seven bacteria strains (3 MB and 4 LAB) were selected and used as starter cultures in the wet fermentation of pulped coffee. The MB and LAB populations varied from 4.48 to 8.43 log CFU g-1 for MB and 3.54 to 8.72 log CFU g-1 for LAB during fermentation. Organic acid concentration (ranged from 0.01 to 0.53 for succinic acid; 0.71 to 8.14 for lactic acid and 0.06 to 0.29 for acetic acid), and volatile compounds (44 compounds were detected in green beans and 98 in roasted beans) were evaluated during fermentation. The most abundant compounds found in roasted beans belong to furans [15], ketones and esters [14], pyridines [13], and pyrazines [12]). Leuconostoc mesenteroides CCMA 1105 and Lactobacillus plantarum CCMA 1065 presented volatile compounds important for coffee aroma. Isovaleric acid; 2,3-butanediol; phenethyl alcohol; ß-linalool; ethyl linoleate; and ethyl 2-hydroxypropanoate could improve cupping qualities.

Production of coffee (Coffea arabica) inoculated with yeasts: impact on quality.

BACKGROUND: The aim of this study was to evaluate the performance of yeasts Saccharomyces cerevisiae CCMA 0200 and Torulaspora delbrueckii CCMA 0684 in Mundo Novo and Catuaí varieties processed by the wet method and the impact on sensory quality and compounds profile. The microbiota was evaluated by surface plating, and the compounds were evaluated by high-performance liquid chromatography and gas chromatography-mass spectrometry. Sensorial analysis was performed using the cupping test (Specialty Coffee Association). RESULTS: T. delbrueckii CCMA 0684 was better adapted to the process and remained for up to 72 h of drying. Eighteen volatile compounds were detected in green coffee and 75 in roasted coffee. 2-Furanmethanol propanoate and 2-ethyl-3,5-dimethylpyrazine were identified only in the inoculated treatments, and these are important contributors to the coffee aroma. All treatments received scores greater than 80 in the sensory analysis. CONCLUSION: T. delbrueckii CCMA 0684 presented better results in relation to the sensorial analysis and is preferable for the varieties and processing method studied. The use of starter cultures is a viable method with which to obtain high-quality coffees with a distinct flavor and thus add to value to the product. © 2019 Society of Chemical Industry.

Assessing the efficiency in assisted depuration of coffee processing wastewater from mixed wild microbial selected inoculum.

This work evaluated the efficiency of bacterial bio-augmentation to the biological treatment of coffee processing wastewater (CPWW) in a pilot wastewater treatment plant (WTP). Biochemical oxygen demand (BOD) and chemical oxygen demand (COD) values were the basis for the treatment efficiency. Serratia marcescens CCMA 1010 and CCMA 1013, Corynebacterium flavescens CCMA 1006 and Acetobacter indonesiensis CCMA 1002 were previously selected. The microbial cocktail was inoculated and persisted in CPWW during all treatments. The richness of wild species was a little altered over time and up to nine species were found in each sampled season. The microbiota composition presented variation of a total of 13 species, despite the inoculation of the microbial inoculum. The biodegradability index of effluent, close to 0.5, was favourable to biological treatment. The pollution parameters of CPWW were decreased in function of the variation of community composition and microbial activity. The greatest reduction of BOD (~ 33%) and COD (~ 25%) was observed between 72 h and 8 days of the biological treatment. The CPWW toxicity in Allium cepa seeds was lower by up to 60%, and the germination index (GI) exceeded 100% in the treated CPWW. The results of the CPWW biological treatment by bio-augmentation from native micro-organisms in the pilot-scale WTP indicated the greatest efficiency relating to the spontaneous biological treatment of CPWW. After this treatment, the discharge of effluent in the environment would not have toxic effects on the plants.

Volatile compounds flavoring obtained from Brazilian and Mexican spirit wastes by yeasts.

Vinasse is a waste obtained from the production of beverages, such as tequila and cachaça. The presence of acids, alcohols, sugars, minerals, amino acids, peptides, and nitrogen salts make vinasse a hazardous liquid waste to the environment, affecting the fauna, flora, and microbiota of rivers and lagoons. This study used biological treatment concomitant to volatile compound production. The yeasts used in the study were Saccharomyces cerevisiae (CCMA 0187 and CCMA 0188), Candida parapsilosis (CCMA 0544), and Pichia anomala (CCMA 0193). A higher percentage reduction in chemical and biochemical oxygen demand was observed in the tequila vinasse than in the cachaça vinasse. However, a higher production of volatile compounds was observed in the cachaça vinasse. C. parapsilosis CCMA 0544 produced the highest concentration of 2-phenylethanol (162 mg L-1). These results indicated that the environmental damage of vinasse can be reduced by treating vinasse with yeasts, and this treatment produces aroma compounds. This biological treatment has high economic potential, especially for the tequila industry.

Microbial community and physicochemical dynamics during the production of 'Chicha', a traditional beverage of Indigenous people of Brazil.

The microbial community of artisanal corn fermentation called Chicha were isolated, purified and then identified using protein profile by Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF) and confirmed by partial ribosomal gene sequencing. Samples from Chicha beverage were chemically characterized by gas and liquid chromatography (HPLC and GC-MS). Aerobic mesophilic bacteria (AMB) (35.8% of total of isolated microorganisms), lactic acid bacteria (LAB) (21.6%) and yeast (42.6%) were identified. Species of the genera Klebsiella, Bacillus, Staphylococcus, Micrococcus, Enterobacter, and Weissella were identified. Rhodotorula mucilaginosa, Lodderomyces elongisporus, Candida metapsilosis, and C. bohicensis were the yeasts found. The LAB isolates detected were responsible for the high concentrations of lactic acid found during the fermentation process (1.2 g L- 1), which is directly related to the decrease in pH values (from 6.95 to 3.70). Maltose was the main carbohydrate detected during corn fermentation (7.02 g L- 1 with 36 h of fermentation). Ethanol was found in low concentrations (average 0.181 g L- 1), making it possible to characterize the beverage as non-alcoholic. Twelve volatile compounds were identified by gas chromatography; belonging to the groups acids, alcohols aldehydes, acetate and others. MALDI-TOF was successfully used for identification of microbiota. Weissella confusa and W. cibaria were detected in the final product (after 36 h of fermentation), W. confusa is often classified as probiotic and deserve further application studies.

Lipid production by yeasts grown on crude glycerol from biodiesel industry.

The main carbon source used for growth by four yeast strains (Yarrowia lipolytica CCMA 0357, Y. lipolytica CCMA 0242, Wickerhamomyces anomalus CCMA 0358, and Cryptococcus humicola CCMA 0346) and their lipid production were evaluated, using different concentrations of crude and pure glycerol and glucose. Whereas crude glycerol (100 g/L) was the main carbon source used by Y. lipolytica CCMA 0357 (nearly 15 g/L consumed at 120 hr) and W. anomalus CCMA 0358 (nearly 45.10 g/L consumed at 48 hr), pure glycerol (150 g/L) was the main one used by C. humicola CCMA 0346 (nearly 130 g/L consumed). On the other hand, Y. lipolytica CCMA 0242 used glucose (100 g/L) as its main source of carbon (nearly 96.48 g/L consumed). Y. lipolytica CCMA 0357 demonstrated the highest lipid production [about 70% (wt/wt)], forming palmitic (45.73% of fatty acid composition), stearic (16.43%), palmitoleic (13.29%), linolenic (10.77%), heptadecanoic (4.07%), and linoleic (14.14%) acids. Linoleic acid, an essential fatty acid, was produced by all four yeast strains but in varying degrees, representing 70.42% of the fatty acid profile of lipids produced by C. humicola CCMA 0346.

Use of lignocellulose biomass for endoxylanase production by Streptomyces termitum.

Actinobacteria isolates from Brazilian Cerrado soil were evaluated for their ability to produce enzymes of the cellulolytic and xylanolytic complex using lignocellulose residual biomass. Preliminary semiquantitative tests, made in Petri plates containing carboxymethylcellulose and beechwood xylan, indicated 11 potential species producing enzymes, all belonging to the genus Streptomyces. The species were subsequently grown in pure substrates in submerged fermentation and analyzed for the production of enzymes endoglucanase, ß-glucosidase, endoxylanase, and ß-xylosidase. The best results were obtained for endoxylanase enzyme production with Streptomyces termitum(UFLA CES 93). The strain was grown on lignocellulose biomass (bagasse, straw sugarcane, and cocoa pod husk) that was used in natura or acid pretreated. The medium containing sugarcane bagasse in natura favored the production of the endoxylanase that was subsequently optimized through an experimental model. The highest enzyme production 0.387 U mL-1, (25.8 times higher), compared to the lowest value obtained in one of the trials, was observed when combining 2.75% sugar cane bagasse and 1.0 g L-1 of yeast extract to the alkaline medium (pH 9.7). This is the first study using S. termitum as a producer of endoxylanase.