Application crude multienzyme extract from Aspergillus niger as a pretreatment for the extraction of essential oil from Croton argyrophyllus leaves.

Leaves of Croton argyrophyllus contain essential oil with promising active components for the development of drugs and botanical insecticides. In this study, we evaluated the enzymatic pretreatment process to increase the extraction of essential oil from fresh and dried leaves of C. argyrophyllus. Pretreatment was carried out using a crude multienzymatic extract obtained via solid-state fermentation of forage palm by Aspergillus niger, and the extraction was performed by hydrodistillation. A Doehlert matrix was used to optimize the enzymatic pretreatment variables temperature and enzymatic extract. The effect of pretreatment time was also investigated. At optimum experimental conditions, 41.34°C, 140 min, and 130.73 mL of enzyme in 369.27 mL of water, the essential oil yield from fresh leaves subjected to enzymatic pretreatment increased by 9.35% and that from dry leaves by 6.77%. Based on chromatographic analysis (GC-MS), no compound was degraded in the extraction process. Micromorphological analysis confirmed the rupture of the glandular trichomes, favoring essential oil release. Therefore, enzymatic pretreatment associated with hydrodistillation increased the essential oil yield and is a promising application to obtain essential oil for therapeutic purposes without altering its composition.

Evaluation of the influence of the antibiotic ciprofloxacin in the development of an Old World screwworm fly, Chrysomya putoria.

Chrysomya putoria (Wiedemann) (Diptera: Calliphoridae), an Old World screwworm fly, is a species with potential for maggot therapy practice and has been described in myiasis and forensic entomology studies. The objective of the present study was to assess the action of different ciprofloxacin concentrations on the growth and development of C. putoria. First instar maggots of the third generation were raised on 60 g of chicken gizzard homogenate in 65% agar diet and received ciprofloxacin chloridrate. Each concentration of the antibiotic tested (3.33 µg/mL, 6.66 µg/mL, and 13.33 µg/mL) and the control (no antibiotic) were replicated four times (40 maggots/replication). The control received distilled water instead of the antibiotic. Maggots were kept in an acclimatized chamber at 30° C during the day and 28° C at night, with 70 + 10% RH and a 14:10 L:D photoperiod. They were weighed in batches of five and stored in test tubes sealed with nylon fabric and elastic. Microsoft Excel and STAT were used for the analysis. The variation among the maggot weight means and the duration of the maggot stage, pupal stage, and time to total development (neolarvae to adult) were analyzed by Student's t-test (α= 5%). The viabilities and the normality rates were compared using ANOVA, and the expected sex ratio frequency was tested by the chisquared test (χ(2)). There was no significant difference among the four treatments regarding mean individual maggot weight, mean duration of the maggot inoculation until abandonment, the duration of the maggot and pupal stages, and the total duration of all stages. The sex ratios found in the four treatments did not differ from the expected. Only treatment 2 (6.66 µg/mL concentration of ciprofloxacin) differed significantly from the control in maggot and total viability. The antibiotic did not seem to alter C. putoria development in the postembryonic period.

Alternative diets for Chrysomya putoria, an Old World screwworm fly.

Abstract The purpose of this study was to evaluate the post-embryonic development of Chrysomya putoria (Wiedemann 1818) (Diptera: Calliphoridae) reared on a diet of gizzard or gizzard/agar homogenate, with a diet of beef used as the control. Four replicates per treatment were performed (60 mL of each diet). The gizzard (60%), distilled water, and agar homogenate were combined in a blender. Each replicate consisted of 40 newly hatched larvae of C. putoria (5(th) generation). Each glass beaker containing a diet was inserted into a larger flask containing sawdust, which was covered with a nylon cloth held in place by an elastic band. The larvae were weighed and stored in test tubes sealed with a nylon cloth and an elastic band. The average temperature, measured with a thermohygrograph, was 20.6 °C, and the average relative humidity was 67.7%. The variation in the mean weight of mature larvae and in the duration of the larval, pupal, and total stages (newly hatched larvae to imagoes) were analyzed by Student's t-test (α = 5%), while viability was compared by ANOVA. The sex ratio was evaluated by the chi-squared test. The average duration of the period from the larval to imago stage was 8.868 days on the beef diet, 8.676 on the gizzard diet, and 9.067 on the gizzard/agar homogenate diet. Larval survival rates on these diets were 98, 92, and 73%, respectively, while pupal viabilities were 98, 91, and 71%, respectively, and larva-to-imago viabilities were 93, 83, and 64%, respectively. The duration of the pupal period differed significantly between the blowflies reared on the beef and gizzard/agar homogenate diets. The two diets proved to be good alternatives for rearing C. putoria.