Animal-microbe symbioses are often stable for millions of years. An example is the clade consisting of social corbiculate bees-honeybees, bumblebees, and stingless bees-in which a shared ancestor ...acquired specialized gut bacteria that subsequently diversified with hosts. This model may be incomplete, however, as few microbiomes have been characterized for stingless bees, which are diverse and ecologically dominant pollinators in the tropics. We surveyed gut microbiomes of Brazilian stingless bees, focusing on the genus Melipona, for which we sampled multiple species and biomes. Strikingly, Melipona lacks Snodgrassella and Gilliamella, bacterial symbionts ubiquitous in other social corbiculate bees. Instead, Melipona species harbor more environmental bacteria and bee-specific Starmerella yeasts. Loss of Snodgrassella and Gilliamella may stem from ecological shifts in Melipona or the acquisition of new symbionts as functional replacements. Our findings demonstrate the value of broadly sampling microbiome biodiversity and show that even ancient symbioses can be lost.
In recent years, several studies have been developed to understand the impact of fermentation on the final quality of coffee and have indicated that postharvest processing could be a determinant of ...quality. However, a trend has appeared as a scientific counterpoint, indicating that the interactions between soil, fruit, altitude, and slope exposures with respect to the Sun are important to understand the behavior of the microbiome in coffee. Studies on the microbiota of coffee have addressed its role during the fermentation process, however the knowledge of indigenous microorganisms harbored in fruits and soil of coffee trees growing in fields are essential, as they can contribute to fermentation. Therefore, the aim of this work was to evaluate the influence of topographic and edaphic factors on the bacterial and fungal communities present in the soil and in the fruits of Coffea arabica trees. Samples of fruits and soil were collected from different growing areas at different altitudes and soil conditions. The microbial DNA was extracted and sequenced. The results showed the contribution of environmental factors in the structure of bacterial and fungal communities. The richness, evenness and diversity of the mycobiome and bacteriome were higher in the soil than in the fruits, independent of altitude. In addition, coffee trees at higher altitudes tended to have more bacteria shared between the soil and fruits. The co-occurrence/co-exclusion network showed that bacteria-bacteria connections were greater in higher altitudes. On another hand, fungi-fungi and fungi-bacteria connections were higher in low altitudes. This was the first study that evaluates in deep the influence of environmental factors in the microbiota habiting fruits and soil coffee trees, which may affect the coffee beverage quality.
Agroecology aims to maintain ecosystem services by minimizing the impact of agriculture and promoting the use of biological potential. Arbuscular mycorrhizal fungi (AMF) are elements which are key to ...improving crop productivity and soil quality. It is pertinent to understand how agricultural management in the tropics affects the AMF spatio-temporal community composition, especially in crops of global importance, such as coffee (Coffea arabica L.). Soil and root samples were collected from three localities under three management systems (agroecological, conventional and forest fragment), during the phenological stages of coffee (flowering, grain filling, harvesting). Spores were extracted for morphological identification and molecular community analysis by PCR-DGGE. Dendrograms were prepared and the bands were sequenced and analyzed by bioinformatics. No differences were observed in the richness of morphospecies between management systems, localities and period, but little is known about tropical species. Molecular analysis showed that the agroecological management system was similar to natural forest and with a higher diversity indices than conventional management. Locality and period of sample affect AMF community composition. It is necessary to associate classical taxonomic evaluations with molecular biological techniques because different approaches can lead to different outcomes. This study contributes to the understanding of the impact of agriculture management systems on AMF and provides evidence that agroecology is a management system applicable to sustainable coffee production.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Post-harvest processing and microbial fermentation of coffee fruits play an essential role in the metabolites formation that influence the nutritional and sensory quality of the beverage. Thus, the ...objective of this study was to analyze the effect of coffee cherries processing and fermentation conditions on the microbial communities and the chemical and sensory quality of the beverage. Induced fermentation changed in the bacteria and fungi communities (Treatments: T1, T3, and T7).
Klebsiella
sp. inoculation (T1) allowed an increase in richness of bacteria and 81 points in the sensory score over the fermentation time. However, there was a reduction in richness of microbial community in treatments with
Saccharomyces cerevisiae
(T3 and T7)
.
An increase in the indexes of microbial diversity was observed in 72 h in treatment with coffee pulp (T2). In treatment with coffee cherries and spontaneous fermentation (T4) had a higher sensory score than other treatments, indicating a sensory gain from 36 to 72 h. Coffee cherries with superficial disinfection (T5) had a reduction in microbial profile, but did not change the final score of the beverage over the 72 h. In T6 (floaters fruits) was observed an alteration in the fungal community (36–72 h) and the lowest sensory score. The impact of adding water on coffee fermentation was dependent on time (T3 and T7). Furthermore, 5-hydroxymethylfurfural has a positive correlation with the final score of the beverage. Thus, microbial profile and sensory score of beverages are dependent of conditions of processing of coffee fruits and fermentation.
Growing concerns regarding the impact of the accumulation of plastic waste over several decades on the environmental have led to the development of biodegradable plastic. These plastics can be ...degraded by microorganisms and absorbed by the environment and are therefore gaining public support as a possible alternative to petroleum-derived plastics. Among the developed biodegradable plastics, oxo-biodegradable polymers have been used to produce plastic bags. Exposure of this waste plastic to ultraviolet light (UV) or heat can lead to breakage of the polymer chains in the plastic, and the resulting compounds are easily degraded by microorganisms. However, few studies have characterized the microbial degradation of oxo-biodegradable plastics. In this study, we tested the capability of Pleurotus ostreatus to degrade oxo-biodegradable (D2W) plastic without prior physical treatment, such as exposure to UV or thermal heating. After 45 d of incubation in substrate-containing plastic bags, the oxo-biodegradable plastic, which is commonly used in supermarkets, developed cracks and small holes in the plastic surface as a result of the formation of hydroxyl groups and carbon-oxygen bonds. These alterations may be due to laccase activity. Furthermore, we observed the degradation of the dye found in these bags as well as mushroom formation. Thus, P. ostreatus degrades oxo-biodegradable plastics and produces mushrooms using this plastic as substrate.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The majority of the textile dyes are harmful to the environment and potentially carcinogenic. Among strategies for their exclusion, the treatment of dye contaminated wastewater with fungal extract, ...containing lignin peroxidase (LiP), may be useful. Two fungi isolates, Pleurotus ostreatus (PLO9) and Ganoderma lucidum (GRM117), produced the enzymatic extract by fermentation in the lignocellulosic residue, Jatropha curcas seed cake. The extracts from PLO9 and GRM117 were immobilized on carbon nanotubes and showed an increase of 18 and 27-fold of LiP specific activity compared to the free enzyme. Also, LiP from both fungi extracts showed higher Vmax and lower Km values. Only the immobilized extracts could be efficiently reused in the dye decolourization, contrary, the carbon nanotubes became saturated and they should be discarded over time. This device may offer a final biocatalyst with higher catalytic efficiency and capability to be reused in the dye decolourization process.
The genus Tulasnella often forms mycorrhizas with orchids and has worldwide distribution. Species of this genus are associated with a wide range of orchids, including endangered hosts. Initially, ...species identification relied mostly on morphological features and few cultures were preserved for later phylogenetic comparisons. In this study, a total of 50 Tulasnella isolates were collected from their natural sites in Minas Gerais, Brazil, cultured, and subjected to a phylogenetic analysis based on alignments of sequences of the internal transcribed spacer (ITS) of the nuclear ribosomal DNA. Our results, based on phylogeny, integrated with nucleotide divergence and morphology, revealed the diversity of isolated Tulasnella species, which included four new species, namely, Tulasnella brigadeiroensis, Tulasnella hadrolaeliae, Tulasnella orchidis and Tulasnella zygopetali. The conservation of these species is important due to their association with endangered orchid hosts and endemic features in the Brazilian Atlantic Forest.
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•Microbial richness increases depending on the condition of the fermentation.•Microorganisms actions could be correlated with sensory attributes.•Fermentation conditions promote ...sensory and chemical changes in coffee.
In view of the possibility of diversifying metabolic routes promoted by fermentation, this study proposed a new processing method for coffee, which consists of adapting a technique already consolidated in winemaking, carbonic maceration. The assay occurred under anaerobic conditions with different time and temperature fermentation. The aim of this study was to determine the differences in coffee characteristics (sensorial, chemical, and microbial) after carbonic maceration and fermentation. Specialty Coffee Association protocol, nuclear magnetic resonance, and denaturing gradient gel electrophoresis were used in these analyzes. A significant functional relationship between global score and temperature (38 °C), for the fermentation time of 96 h was observed. Bacterial diversity and sensory characteristics had a positive correlation. Furthermore, trigonelline, formic acid, hydroxymethylfurfural, lipids, and γ-butyrolactone also contributed to score and sensory quality of coffee beverage. Thus, our data show consistent factors to infer on the microbiological action on the sensory quality of coffee beverage.
Mushrooms present high potential to be used as a source of lithium (Li), but bioaccumulation of Li and other minerals, redox status and bioavailability are specific to each species, depending on the ...dosage and type of salt used. We investigated the bioaccessibility, oxidizing activity and co-accumulation of minerals in Li-enriched mushrooms in Pleurotus ostreatus (PLO 02) and Pleurotus djamor (PLO 13). Mushrooms were produced in coffee husks enriched with lithium chloride or lithium carbonate at different concentrations. It was found that PLO 02 is more sensitive to high concentrations of Li than PLO 13, which presented higher mushroom production rate. It was observed a positive correlation between Li accumulation and other minerals present in the substrate and the effect of Li on fungus redox status. Bioaccessibility in both fungi was higher in the Li-enriched mushrooms when compared to the medicinal lithium carbonate tablet, and these mushrooms can co-accumulate minerals and increase oxidative activity. It confirms that Li-enriched mushrooms can be an alternative and healthy source of Li.
•Pleurotus djamor presented ability to accumulate super doses of Li.•Lithium salts can affect the absorption of other minerals by the genus Pleurotus.•Lithium salts can reduce or increase the oxidizing activity, depending on the dosage.•The bioaccessibility of lithium in mushrooms is greater than medicinal lithium carbonate.
We studied the biodegradation of green polyethylene (GP) by Pleurotus ostreatus. The GP was developed from renewable raw materials to help to reduce the emissions of greenhouse gases. However, little ...information regarding the biodegradation of GP discarded in the environment is available. P. ostreatus is a lignocellulolytic fungus that has been used in bioremediation processes for agroindustrial residues, pollutants, and recalcitrant compounds. Recently, we showed the potential of this fungus to degrade oxo-biodegradable polyethylene. GP plastic bags were exposed to sunlight for up to 120 days to induce the initial photodegradation of the polymers. After this period, no cracks, pits, or new functional groups in the structure of GP were observed. Fragments of these bags were used as the substrate for the growth of P. ostreatus. After 30 d of incubation, physical and chemical alterations in the structure of GP were observed. We conclude that the exposure of GP to sunlight and its subsequent incubation in the presence of P. ostreatus can decrease the half-life of GP and facilitate the mineralization of these polymers.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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