The physical or morphological integrity of the coffee bean during post-harvest processing directly influences the economic value and sensory quality of the coffee beverage. Breakdowns in the outer ...layers of the beans are characteristics observed for the morphological and economic classification of coffee beans during the commercialization of this product. However, physical changes in the inner layers of the beans that are not seen with the naked eye can also influence the sensory quality of the coffee. Therefore, the objective of this study was to relate changes in the physical structure of coffee beans roasted by four different processes (light, medium, dark, and baked) with the sensory attributes of the beverage. The analyses of the physical characteristics of the coffee beans were carried out by X-ray microtomography and the sensory profile was determined using the Specialty Coffee Association of America protocol. The roasting profile with the highest sensory scores showed higher values for total pore space volume and a negative Euler number. However, the roasting profiles that fluctuated between the highest and lowest of scores of the sensory attributes did not present standardized behavior for the connectivity, Euler number, and total pore space volume. Hence, morphological or physical changes in the coffee beans caused by the different types of roasting correlate with changes in the sensorial profile. Furthermore, the sensory discrimination of these coffee beans among the different roast profiles may be observed by the joint analysis of the flavor and fragrance scores.
The use of by-products reduces costs for the cultivation of Se-enriched mushrooms, whose consumption could reduce problems associated with Se deficiency. Treatments to decrease by-products ...contamination, such as sterilization, are also expensive and thus are not accessible for small producers. In this way, this work aimed to evaluate the influence of Se at 25 mg kg
−1
(sodium selenite) on the growth, composition, and antioxidant activity of
Pleurotus ostreatus
mushrooms cultivated on substrates composed of sugarcane bagasse (CB) and spent brewer’s grain (BSG) treated with a hydrated lime solution. The use of sodium selenite did not affect the biological efficiency (33.79–52.31 g 100 g
−1
), antioxidant activity (32.79–44.67%), and phenolic content (458.78–754.96 mg EAG 100 g
−1
) of mushrooms, which had high concentrations of protein (17.07–23.50%), fibers (11.13–13.32%) and ash (4.46–7.21%). The mushrooms grown on CB alone presented 179.07 µg g
−1
of Se, so the consumption of 0.31 g of dry mushroom would be sufficient to achieve the recommended daily intake of Se. The CB treated with the hydrated lime solution can be used as an inexpensive and efficient substrate to produce Se-enriched
P. ostreatus
mushrooms.
Graphic Abstract
Coffea arabica
L. and
Coffea canephora
L. are coffee species most consumed and marketed in the world. The coffee crop requires a large amount of nitrogen, which shows the importance of knowledge of ...the population of nitrogen-fixing bacteria (NFB) from the rhizosphere of these crops. These microorganisms may help the reduction of nitrogen fertilizing. However, there is no production of NFB inoculum in the coffee. Therefore, our objective was to evaluate the diversity of potential nitrogen-fixing bacteria (PNFB) in the rhizosphere of
C. arabica
and
C. canephora
. The microbial DNA of the soil was extracted, amplified through PCR, and sequenced at the Illumina Miseq. platform. The PNFB prediction was performed using the program PICRUSt2. Three hundred and thirty-seven amplicon sequence variants (ASVs) were identified as PNFB in two coffee species.
Xanthobacteraceae
,
Rhizobium multhospitiium
,
Rhizobium mesosinicum
, and
Bradyrhizobium
sp. were detected in all samples and main components of the core microbiota of the coffee plant rhizosphere. Some ASVs are exclusive from one of the coffee farms, showing that the coffee specie cultivated may influence the PNFB communities. However, edaphoclimatic factors and soil chemical attributes can also influence the distribution of ASVs in coffee soil. In the
C. canephora
, the PNFB diversity was influenced by the altitude and the soil chemical attributes, while the altitude and the phosphorus content influenced the PNFB population in
C. arabica
. Our results are important to the understanding of the PNFB dynamic in coffee soil and for the agricultural inputs bioprospecting to coffee.
After the collapse of Fundão Dam in Mariana‐MG, Brazil, the discharge of iron ore mining waste into the Doce River watershed negatively impacted the landscape. Monitoring the composition and species ...richness of soil microbiota may be useful bioindicators of ecosystem recovery. This study aimed to compare soil chemical properties, total fungal species, and arbuscular mycorrhizal fungi (AMF) in sites unaffected and affected by mining tailings in the first 3 years after the collapse of Fundão Dam. Soil and root samples were collected in dry and rainy seasons over 3 years in unaffected (adjacent forest and pasture) and affected areas (REC1, REC2, and PASTrec) by mine tailings. Changes in soil chemical properties over the sampling period were measured by routine chemical analyses. Total fungi in the soil was determined by high‐throughput sequencing. AMF community was evaluated using spore number, root colonization, and denaturing gradient gel electrophoresis. Affected sites had higher ranges of pH and lower soil organic matter than unaffected sites. Revegetation had a positive effect on soil fungal community. Increased similarity in AMF DGGE analysis was observed in the two sampling sites over time. A high similarity of total fungi and AMF was observed between REC and pasture areas, suggesting that revegetation strategy employed may be heading towards a pasture condition. Thus, post‐disturbance analysis of this study was important to evaluate of ecosystem recovery affected by the rupture of iron ore mining dam and demonstrated that the soil microbiota was a sensitive bioindicator in this long path of ecosystem recovery.
The rupture of the Fundão dam in Brazil in November 2015 covered the soil with iron ore mining waste (IOMW) and removed vegetation. Arbuscular mycorrhizal fungi (AMF) can benefit vegetation growth ...and soil structure, assisting the rehabilitation of degraded areas. Therefore, the objective of the present work was to evaluate the AMF community structure and investigate the effect of the technosol physicochemical properties in these communities after revegetation programs were adopted in areas affected by IOMW. Soil samples were taken from an undisturbed atlantic forest (UND) and two regions influenced by IOMW, under natural recovery process (REC1) and under revegetation process introduced after the dam rupture (REC2) during the rainy season (February, E1) and dry season (September, E2) of 2017. AMF community structure in both seasons was assessed by PCR-DGGE, spore density, and glomalin-related soil protein (GRSP) content. Soil physical and chemical characteristics were also evaluated and related to the AMF community. In the summer, the AMF community profile was affected by the host plants used for revegetation, as REC2 showed 92% similarity with the natural forest against only 73% of REC1. In the winter, REC1 showed a higher similarity rate with REC2 and UND, as there was already vegetation cover in the area. The number of spores and the content of glomalin were not different between REC1 and REC2, but they were lower than UND. The number of spores in both areas was, on average, 12 (summer) and 8 times (winter) less than UND, and the total glomalin was 22 and 10 times less, respectively. The chemical characteristics of UND and soils under the recovery process (REC1 and REC2) were considerably different due to IOMW deposition. A small change in the soil chemical attributes has been observed after the revegetation in both REC areas, which was very slow toward the rehabilitation process, although the changes in the soil physicochemical characteristics were incipient till the period from 14 months (E1) to 21 months (E2). We concluded that the covering by plants of areas affected by IOMW improves AMF diversity since these fungi are biotrophic. Furthermore, the findings suggest that the short period (six months) can alter AMF communities. Therefore, revegetation processes adopted after dam collapse have promoted land reclamation, but this effect requires further monitoring.
•Iron ore mining waste altered soil biological and physicochemical characteristics.•Revegetation of degraded areas improved abundance and diversity of arbuscular mycorrhizal fungi community.•There is temporal variation in arbuscular mycorrhizal fungi community•Physicochemical changes of soil affect the arbuscular mycorrhizal fungi community.•Arbuscular mycorrhizal fungi are good biological indicators for soil quality monitoring.
ABSTRACT The production of inoculum from arbuscular mycorrhizal fungi (AMF) at a large scale and low cost is essential for establishing methods to assist in producing pineapple plantlets with high ...nutritional and phytosanitary quality. However, this objective is difficult to accomplish because of the biotrophic nature of these fungi. The on-farm multiplication method for AMF inoculum presents a good alternative to supply the demand for the production of glomerospores. This study aimed to multiply and evaluate AMF inoculum originating from isolated species (including Rhizophagus clarus, Claroideoglomus etunicatum) versus native AMF from pineapple and coffee plantations multiplied by the on-farm method on the colonization in pineapple plantlets. Initially, inocula of R. clarus, C. etunicatum, and native AMF (pineapple and coffee) were multiplied by the on-farm method in Sorghum bicolor. After four months, the number of AMF spores and the percentage of viable spores at the layers of 0.00-0.05 and 0.05-0.10 m were evaluated. There were no differences in spore numbers in relation to the source of the inoculum (R. clarus, C. etunicatum, pineapple, and coffee) and evaluated layers, with an average number of 605 spores per 100 cm3 of soil. The percentage of viable spores was greater at the layer of 0.00-0.05 m (76.32 %) compared to the layer of 0.05-0.10 m (72.05 %), regardless of the inoculum source. The viability of the inoculum obtained from C. etunicatum was higher than that from the coffee crop (77.93 and 68.06 %, respectively). Subsequently, the spores were inoculated in pineapple plantlets to assess the rate of colonization. Pineapple plantlets inoculated with AMF had an average of colonization of 18 and 67.73 % after 50 and 180 days cultivation, respectively, with no significant difference being detected between treatments. Therefore, on-farm inoculum production was effective at multiplying the AMF of both isolates of R. clarus and C. etunicatum, as well as for commercial crops (pineapple and coffee), with spores having high viability. Arbuscular mycorrhizal fungi colonized pineapple plantlets independently of the inoculum utilized and favored its growth.
Abstract
The supplementation of nitrogen can be increased by the use of nitrogen-fixing, diazotrophic bacteria such as
Azospirillum brasilense
. These bacteria can act to promote plant growth in ...various plant species, including corn (
Zea mays
L.). However, there is a need to understand the behavior of these bacteria in different agricultural systems. The objective of this study was to evaluate the effect on the growth and yield of corn inoculated with
A. brasilense
, and to identify the type of farming system which benefited most from the use of
A. brasilense
-based inoculants. The experiment conducted over two corn crop seasons was arranged in a 6 × 2 factorial scheme, consisting of six farming systems and the presence or absence of inoculation with the bacteria
A. brasilense
. The farming systems were derived from a long-term experiment with different fertilization systems that has been conducted since 1984. Among these systems, there were three conventional systems (CNT1: conventional no-till without fertilizer; CNT2: conventional no-till with 150 kg ha
−1
of mineral fertilizer + 50 kg ha
−1
of urea; CNT3: conventional no-till with 300 kg ha
−1
of mineral fertilizer + 100 kg ha
−1
of urea), and three organic systems (ONT1: organic no-till with 40 m
3
ha
−1
of organic compost; ONT2: organic no-till with 20 m
3
ha
−1
of organic compost; ONT3: organic no-till with 40 m
3
ha
−1
of organic compost and intercropped with
Canavalia ensiformis
). Although the
Azospirillum
population in the soil before planting was the same for all six systems, the count in the rhizospheric soil was higher in the organic systems, and there was no increase in that count due to inoculation. In this study, the only difference observed was within the CNT1 system, between the inoculated (CNT1-I) and uninoculated (CNT1-NI) treatments. In this system, inoculation resulted in an increase in plant height, in addition to higher concentrations of foliar N and P, and a higher plant survival rate, which culminated in higher yield. Corn inoculated with
A. brasilense
in the CNT1-I treatment showed a significant increase in yield—2839 kg ha
−1
higher than that recorded for CNT1-NI. This study shows that, in the conventional low input treatment CNT1-I, inoculation with
A. brasilense
resulted in an increase in corn growth and yield.
The fungus Pochonia chlamydosporia is one of the most studied biological agents used to control plant-parasitic nematodes. This study found that the isolates Pc-3, Pc-10 and Pc-19 of this fungus ...promote the growth of tomato and lettuce seedlings. The isolate Pc-19 colonized the rhizoplane of tomato seedlings in only 15 days and produced a large quantity of chlamydospores. This isolate was able to use cellulose as a carbon source, in addition to glucose and sucrose. Scanning electron microscopy (SEM) revealed that hyphae of the P. chlamydosporia isolate Pc-10 penetrated the epidermal cells of the tomato roots. These three P. chlamydosporia isolates promote the growth of tomato and lettuce.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The reduction of environmental pollutants has been important for the sustainability (environmental, economic, and social) of the manufacturing companies. The agro-industry annually produces tons of ...vegetable residues that is discarded in the environment. Textile industries have a high rate of dye discharges in water resources. Fungal enzymes produced in plant residues can degrade recalcitrant organic compounds. Thus, the aim of the study was the production, purification, characterization, and use of dye discoloration of enzymes produced by Pleurotus ostreatus (PLO 02 and PLO 06) and Pleurotus eryngii (PLE 05) in Macaúba coconut (Acrocomia aculeate) residue. The initial time of colonization of the substrate was of 18 (P. eryngii) and 22 days (P. ostreratus). After this period, 50 g of substrate were collected every five days to evaluate the enzymatic activity before and after the purification in sephadex G-100 column. All fungal strains had activity of laccase, lignin peroxidase (LiP), manganese peroxidase (MnP), xylanase, cellulase, and lipase in crude protein extract. The enzymes kept the activities from 4 to 60 °C for about 16 h and these activities were higher in acidic than alkaline pH. Furthermore, the enzymes of P. eryngii degraded about 100% of Carmine indigo dye after 24 h of incubation. Therefore, the Macaúba coconut residue is a good substrate for the enzyme production and these enzymes have high degradation capacity of the indigo dye.
Roasting has been used by the coffee industry to promote changes in the physical and chemical structure of coffee beans that influence the sensory quality of coffee beverages. However, there are no ...standardization rules for the temperature and roasting time. Thus, this study evaluated the influence of four roasting profiles obtained by two different roasters on the chemical and sensory quality of the coffee bean. Baked, light, medium, and dark roasting were evaluated using medium infrared spectroscopy and cupping test. Individual and joint effects of temperature and time for each roasting profile were observed on the loss of grain mass. There are specific regions in the infrared spectrum that can be used as markers to discriminate the roasting profiles and the type of roaster used. Despite the difference observed in the ranges of the infrared spectra, the roasters did not present significant differences in the average of the final sensory notes. This result shows the need to use analytical chemical techniques together with sensory analysis in order to better determine differences between coffee samples. Therefore, differences observed in the chemical analyzes and in the sensory attributes of roasted coffee are related to the roasting profile and type of roaster.
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