Evaluation of Cellulolytic and Hemicellulolytic Abilities of Fungi Isolated from Coffee Residue and Sawdust Composts

This study focused on the evaluation of cellulolytic and hemicellulolytic fungi isolated from sawdust compost (SDC) and coffee residue compost (CRC). To identify fungal isolates, the ITS region of fungal rRNA was amplified and sequenced. To evaluate enzyme production, isolates were inoculated onto wheat bran agar plates, and enzymes were extracted and tested for cellulase, xylanase, β-glucanase, mannanase, and protease activities using different azurine cross-linked (AZCL) substrates. In total, 18 isolates from SDC and 29 isolates from CRC were identified and evaluated. Four genera (Aspergillus, Galactomyces, Mucor, and Penicillium) and five genera (Aspergillus, Coniochaeta, Fusarium, Penicillium, and Trichoderma/Hypocrea) were dominant in SDC and CRC, respectively. Penicillium sp., Trichoderma sp., and Aspergillus sp. displayed high cellulolytic and hemicellulolytic activities, while Mucor isolates exhibited the highest β-glucanase and mannanase activities. The enzyme analyses revealed that Penicillium, Aspergillus, and Mucor isolates significantly contributed to the degradation of SDC, whereas Penicillium, Aspergillus, and Trichoderma isolates had a dominant role in the degradation of CRC. Notably, isolates SDCF5 (P. crustosum), CRCF6 (P. verruculosum), and CRCF2 and CRCF16 (T. harzianum/H. lixii) displayed high activity regarding cellulose and hemicellulose degradation, which indicates that these species could be beneficial for the improvement of biodegradation processes involving lignocellulosic materials

有機酸で処理したリン鉱石中のリンに対するイタリアンライグラスの反応

スリランカとトーゴー産のリン鉱石に5Mのクエン酸、シュウ酸、酒石酸溶液を1:2の割合で加え、3日間反応させた。シュウ酸と酒石酸で処理したリン鉱石は容易に乾燥し、ほとんど全てのリン酸が水溶性となった。クエン酸で処理したリン鉱石は乾燥しにくく、また水溶性リン酸の割合も全リン酸の50%程度であった。これら有機酸で処理したリン鉱石のリン源としての有効性を、イタリアンライグラスを供試作物とし、マサ土(花崗岩風化土壌)を用いた土耕ポット試験で過燐酸石灰と比較した。クエン酸処理したスリランカ産リン鉱石を除き、他の全ての有磯酸処理リン鉱石は播種後168日目のイタリアンライグラスの乾物収量を過燐酸石灰と同程度に増加させた。酒石酸で処理したトーゴー産リン鉱石におけるリンの回収率は58%で、過燐酸石灰(52%)や酒石酸処理スリランカ産リン鉱石(53%)より有意に高かった。有機酸処理したリン鉱石を与えた区の跡地土壌の可給態リン(Olsen P)濃度とpHは、過燐酸石灰施与区や無リン酸区(対照区)より有意に高かった。実験期間を通じてイタリアンライグラスの生育と養分吸収に及ぼす有機酸処理リン鉱石施与の悪影響は認められなかった。以上の結果から、酸性土壌に生育する作物に対し、少なくとも酒石酸処理したリン鉱石のリン源として有効性は過燐酸石灰より良好であると判断された。Two phosphate rocks (PRs) from Sri Lanka and Togo were acidulated with 5 M of citric, oxalic or tartaric acid at 2:1 acid:rock ratio for three days. The resulting materials treated with oxalic and tartaric acid were easily dried up and nearly all the P was in water soluble form. The PRs treated with citric acid were rather difficult to dry and contained about 50% of the total P in water soluble form. The effectiveness of the materials as phosphorus sources were compared with that of single superphosphate in acidic granitic regosol with Italian ryegrass as the test crop. All the acid treatments were as effective as single superphosphate in increasing the dry matter yield of Italian ryegrass at 168 days after planting except the citric-acid treated Sri Lanka PR. Phosphorus recovery by the plants from tartaric-acid treated Togo PR was 58%, which was significantly greater (P<0.05) than those from single superphosphate (52%) and tartaric-acid treated Sri Lanka PR (53%). Significantly higher levels of available P (OLSEN P) and pH were found in the cropped soils which received the organic-acid treated PRs than those of the soils which received single superphosphate and control at the end of the experiment. No adverse effect of the organic-acid treated PRs on the growth and nutrient uptake by Italian ryegrass was observed throughout the growth period. These results indicate that at least the tartaric-acid treated PRs could be better sources of P to crops growing on acid soils than single superphosphate

Nitrogen uptake and transpiration by plant effects on nitrate leaching from granitic regosol

Field and soil column experiments were conducted to analyze the effects of N uptake and transpiration by corn on nitrate-nitrogen (NO3-N) leaching in a granitic regosol and to evaluate the contribution of plant growth to the reduction of NO3-N leaching. In the field experiment, NO3-N leaching, N uptake by corn and retained N (inorganic N and microbial biomass N) were monitored in conventional planting density (CPD), high planting density (HPD) and no planting (NP) treatments. Nitrogen (N) was applied as (NH4)2SO4 at the rate of 300 kg N ha-1 and corn (Zea mays L.) was sown. In the soil column experiment, 1500 mg N column-1 was applied and corn was sown in four treatments; the no plant (NP), 1-, 2- and 4-plant column-1. NO3-N leaching, N uptake and transpiration by corn and retained NO3-N in the soil were measured. In the field experiment, cumulative NO3-N leaching in the NP treatment was 208 kg N ha-1 from 38 to 49 days after treatment. In the CPD and HPD treatments, NO3-N leaching was reduced to 148 kg N ha-1 and 73 kg N ha-1, respectively. N uptake by corn and retained N in the soil increased with increasing of planting density. Cumulative NO3-N leaching was negatively correlated with N uptake by corn (r = -0.940, P < 0.01, n = 10). NO3-N leaching decreased as N uptake by corn increased above 60 kg N ha-1. In the soil column experiment, cumulative NO3-N leaching was decreasing with increasing of planting density because of increasing of N uptake by corn and the amount of retained NO3-N in soil. The amount of retained NO3-N in soil was positively correlated with transpiration by corn (r = 0.943, P < 0.01, n = 12). We concluded that NO3-N leaching from a granitic regosol during the rainy season could be reduced by the increasing of planting density due to the increase of N uptake by plants and the increase of retained N in soil derived from the increasing of transpiration by plants

The Effect of C/Si Ratio and Fluorine Doping on the Gas Permeation Properties of Pendant-Type and Bridged-Type Organosilica Membranes

A series of pendant&ndash;type alkoxysilane structures with various carbon numbers (C1&ndash;C8) were used to fabricate sol&ndash;gel derived organosilica membranes to evaluate the effects of the C/Si ratio and fluorine doping. Initially, this investigation was focused on the effect that carbon-linking (pendant&ndash;type) units exert on a microporous structure and how this affects the gas-permeation properties of pendant&ndash;type organosilica membranes. Gas permeation results were compared with those of bridged&ndash;type organosilica membranes (C1&ndash;C8). Network pore size evaluation was conducted based on the selectivity of H2/N2 and the activation energy (Ep) of H2 permeation. Consequently, Ep (H2) was increased as the C/Si ratio increased from C1 to C8, which could have been due to the aggregation of pendant side chains that occupied the available micropore channel space and resulted in the reduced pore size. By comparison, these permeation results indicate that pendant&ndash;type organosilica membranes showed a somewhat loose network structure in comparison with bridged&ndash;type organosilica membranes by following the lower values of activation energies (Ep). Subsequently, we also evaluated the effect that fluorine doping (NH4F) exerts on pendant&minus;type [methytriethoxysilane (MTES), propyltrimethoxysilane (PTMS)] and bridged-type [1,2&ndash;bis(triethoxysilyl)methane (BTESM) bis(triethoxysilyl)propane (BTESP)] organosilica structures with similar carbon numbers (C1 and C3). The gas-permeation properties of F&ndash;doped pendant network structures revealed values for pore size, H2/N2 selectivity, and Ep (H2) that were comparable to those of pristine organosilica membranes. This could be ascribed to the pendant side chains, which might have hindered the effectiveness of fluorine in pendant&ndash;type organosilica structures. The F&ndash;doped bridged&ndash;type organosilica (BTESM and BTESP) membranes, on the other hand, exhibited a looser network formation as the fluorine concentration increased

Shoot and root responses to low phosphorus and their genotypic variability in selected cultivars of Japanese core collections of maize and soybean

Low phosphorus (P) stress in agricultural soils is a global problem in crop production. A greater understanding of the genotype-specific responses under low P stress is imperative for producing P-efficient genotypes. This study first evaluated Japanese core collections of maize (86 landraces) and soybean (94 landraces) to low P under hydroponic conditions. Ten cultivars of each species were further evaluated in a pot experiment with two P supply rates: low P (10 mg P kg−1) and high P (50 mg P kg−1). Root morphology, acid phosphatase (ACP) activity, and rhizosphere soil pH were characterized 30 days after planting. A sufficient genotypic variation was found in both species under both P conditions. A significant decrease in biomass, except in maize cultivar JMC 76 and soybean cultivar GmJMC033, and increased phosphorus use efficiency (PUE) under low P conditions were observed. The maize cultivars: JMC 76, JMC 57, JMC 58, and JMC 8 and soybean cultivars: GmJMC033, GmJMC040, and GmJMC085 showed distinctive root modifications characterized by the high root-to-shoot ratio (RRS), total root length (TRL) and specific root length (SRL) under low P stress indicating their low P tolerance. Maize had more significant ACP activity compared to soybean under low P stress. The maize cultivars, which showed low P tolerance, were highly dependent on root morphological traits rather than physiological traits (ACP activity, rhizosphere acidification, and PUE), whereas soybean cultivars were dependent on both traits. In conclusion, the plasticity of the root system is crucial in both maize and soybean to tolerate P deficiency. These genotype-specific adaptations could be combined with agronomic strategies to enhance the overall P-use efficiency in cropping systems.</p

Bloodstream Infection Caused by Actinomyces neuii subsp. anitratus in a Patient with Breast Cancer: A Case Report and Literature Review

Actinomyces neuii can grow under aerobic culture conditions and shows a gram-positive rod morphology, similar to that of Corynebacterium spp. A. neuii is usually detected in local pus samples, and published cases of A. neuii bloodstream infections are rare. Here, we report a case of bloodstream infection caused by A. neuii subsp. anitratus. A 53-year-old woman with fever and hypotension was referred to our hospital. The patient underwent surgery for breast cancer and received chemotherapy after central venous (CV) port placement. On day 2, a blood culture in an anaerobic bottle yielded positive results, and A. neuii subsp. anitratus was identified via matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI–TOF MS) and 16S rRNA sequencing. The patient was diagnosed with bloodstream infection caused by A. neuii subsp. anitratus with CV port infection. The CV port was removed and antibiotic treatment resulted in symptom improvement so the patient was discharged on day 28 of hospitalization. MALDI–TOF MS and 16S rRNA sequencing were found to be more useful for the identification of A. neuii than for phenotypic identification. Further research on A. neuii subsp. anitratus infections is required to avoid delayed or missed diagnoses