In the study the comparative analysis of test results of drainage of municipal wastewater sludge was conducted with the use of flocculant Praestol 855BS and the mixture of flocculant Praestol 855BS 50% + orange essential oil 50%, as the reagents supporting this process. It was also attempted to reduce unpleasant smells exuding from the drained sludge.
The process of drainage of municipal wastewater sludge was conducted in the laboratory setting centrifuge of MPW-350 type. The variable independent parameters were centrifugation time, centrifugation speed, dosage of flocculant Praestol 855BS as well as dosage of mixture in the proportion of flocculant Praestol 855BS (50%) + orange essential oil (50%). The following parameters were subject to assessment: water content in the sludge, dry mass content in the reflux as well as time of maintenance of the oil’s smell in the sludge. The conducted tests demonstrated that the orange essential oil has an impact on drop in resultant quality parameters of the drainage process of municipal wastewater sludge. Batching of the orange essential oil has an impact on considerable reduction of odours exuding from drained wastewater sludge, and thus on improvement of work conditions connected with operation of centrifugal separators. Bearing in mind both the efficient drainage process of wastewater sludge as well as simultaneous reduction of unpleasant smells exuding from the sludge during this process it is assumed and recommended to simultaneously apply both reagents, that is flocculant Praestol 855BS (50%) and orange essential oil, also in the volume of 50%.
The chemical composition of tea tree (Melaleuca alternifolia) and wintergreen (Gaultheria procumbens) essential oils as well as their phytotoxic effects against two invasive species – Cortaderia selloana and Nicotiana glauca – were studied. Fifty-eight compounds accounting for 98.89–99.94% of the total commercial tea tree and wintergreen essential oils were identified by Gas Chromatography-Mass Spectrometry (GC-MS) analysis. Tea tree essential oil with terpinen- 4-ol (28.37 ± 0.05%) followed by 1,8-cineole (15.81 ± 0.06%), γ-terpinene (15.60 ± 0.03%), α-pinene (10.92 ± 0.08%) and α-terpinene (8.52 ± 0.01%) as the main compounds did not produce significant effects against seed germination and hypocotyl growth of N. glauca, but showed significant effects in seed germination inhibition of C. selloana (34.69%) as well as in hypocotyl (60.96%) and radicle (62.55%) growth, at the highest dose (1 μl ⋅ ml–1) assayed. High amounts of methyl salicylate (99.63 ± 0.02%) were found in G. procumbens essential oil with remarkable phytotoxic effects in C. seollana. Methyl salicylate inhibited seed germination (77.38%) and hypocotyl and radicle growth (96.38% and 96.65%, respectively) at the highest dose (1 μl ⋅ ml–1) assayed. Wintergreen essential oil constitutes an eco-friendly alternative to control the high capacity of invasiveness of C. selloana.
The in vitro anti-Babesia canis activities of nine essential oils were investigated. Among the tested essential oils Achillea millefolium, Eugenia caryophyllus and Citrus grandis were the most active (IC50 values of 51.0, 60.3 and 61.3 μg/mL, respectively). The oils from Abies sibirica, Rosmarinus officinalis, Eucalyptus globulus, Cinnamonum zeylanicum, Mentha piperita and Pinus sylvestris were less active (IC50 values of 134.3, 237.3, 239.3, 367.9, 837.5 and 907.3 μg/mL, respectively). The results support the concept that some essential oil constituents may be useful in the clinical management of babesiosis.
The aim of this study was to investigate interactions between conventional antifungal drug and essential oils against isolates of Malassezia pachydermatis. Antifungal activity of Cinnamomum cassia, Melaleuca alternifolia, Mentha piperita, Origanum vulgare and Syzygium aromaticum essential oils were tested against 19 strains of M. pachydermatis isolated from healthy dogs and reference strain M. pachydermatis CBS 1879. The checkerboard assay was used to search for in- teractions. Synergism was observed for the combination of clotrimazole with Melaleuca alternifolia essential oil, Mentha piperita and Origanum vulgare. The combinations of Cinnamomum cassia and Syzygium aromaticum essential oils with clotrimazole showed indifferent effect. Additive antimicrobial activity was observed for the combination of clotrimazole with Syzygium aromaticum and Melaleuca alternifolia essential oils against reference strain. The obtained results showed synergistic interactions between essential oils and clotrimazole which could improve effectiveness of this antifungal drug.
Luffa cylindrica M. Roem, is commonly called sponge gourd or Egyptian cucumber. In September 2018, several plants showing symptoms of powdery mildew were observed in some fields at different locations in Egypt. Identification and pathogenicity tests indicated that the causal fungus of powdery mildew disease of luffa cylindrica was Podosphaera xanthii. Results of surveyed luffa plants grown at different field localities of northern Egypt, for powdery mildew disease incidence revealed that the maximum record (57.33%) of disease occurrence was recorded in some fields belonging to Beheira governorate followed by, Alexandria and Sharqia (53.67% and 48.00%, respectively). Meanwhile, fewer occurrences were observed in Kafer El-Sheekh governorate (45.33%). We applied biocontrol agents as a foliar spray against powdery mildew in vitro and under field conditions. The effects of some essential oils, organic acid and bioproducts were also studied. All treatments significantly reduced P. xanthii compared to untreated plants. Chaetomium globosum and Saccharomyces cerevisiae alone or grown on rice straw and/or bagas showed highly reduced disease incidence compared to the other treatment. From the present study it could be suggested that the usage of biocontrol formulated on rice straw might be used as an easily applied, safe and cost effective control method against powdery mildew diseases.
The adverse effects of synthetic acaricides on humans, animals, non-target organisms and the ecosystem are serious problems. Thus, there is a new trend to use nanotechnology for developing new, natural, bio and safe acaricides for mite control in green-pest management. This is the first work for preparing a nanoformulation of rosemary essential oil (EO) and evaluating its effect against the two-spotted spider mite Tetranychus urticae Koch. GC/MS analysis of rosemary EO showed that 1,8 cineole (31.45%), borneol (11.07%), α-pinene (10.91%), D-limonene (9.19%), L-linalool (8.86%), D-camphor (7.32%), γ-terpinene (3.92%), linalyl acetate (3.37%), α-terpineol (3.32%), and p-cymene (1.82%) were the major components. After 6 min of sonication, a nanoemulsion of rosemary EO was formulated with a droplet size of 139.9 nm. The balance between oil (lyophilic) and surfactant (hydrophilic) was correlated with the droplet size and the stability of the nanoemulsion. Spray application of rosemary nanoemulsion showed high acaricidal activity against immature and adult two-spotted spider mites T. urticae with LC50 723.71 and 865.68 μg · ml−1 and the toxicity increased by 54.15 and 52.69% for immature and adult mites, respectively. There were no toxic effects or mortality of rats treated with rosemary nanoemulsion. High acaricidal activity, stability, and safety of rosemary nanoemulsion make this nanoformulation a possible green and nano-acaricidal product. Further studies under field conditions are necessary to study the acaricidal efficiency of rosemary nanoemulsion against two-spotted spider mites and the toxic effect on predacious mites.