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Microorganisms such as bacteria and fungi are developing resistance to the current therapies easily and the presently available antibacterial, antifungal agents and pesticides are certainly very pricey and harmful. So, the necessary shift to use natural antimicrobial extract (Periplaneta americana chitosan) seems to be more effective, economic and safe to the public health. The American cockroach chitosan was dissolved in 1 % acetic acid and diluted to different concentrations then, seeded in 96 well tissue culture plates to evaluate the antibacterial activity by using MTT assay and the microbial growth was calculated by ELISA microplate reader. The American cockroach chitosan showed an equal minimum inhibitory concentration (MIC) antibacterial action against two (Gram-positive) bacterial strains Staphylococcus aureus, and Bacillus subtilis, recording MIC = 2000 µg/ml. Also, chitosan showed MIC antibacterial activity against Escherichia coli and Salmonella typhimurim (Gram-negative) bacteria recording MIC = 1000 µg/ml, and MIC = 2000 µg/ml respectively. While chitosan showed non-antifungal activity against Candida albicans. Natural chitosan could be considered as a determined factor affecting on the biological activities mentioned in this study.

The exoskeleton of a cockroach plays a major role in protecting it from pathogenic microbes. It is well known that the main component of the exoskeleton is the chitin which is considered the source of chitosan. This study aimed at investigating the anticancer activity of chitosan prepared from the American cockroach. Chitosan was prepared and characterized with solubility in 1% acetic acid and Fourier transform infrared spectroscopy (FT-IR) analysis. The cytotoxicity of chitosan was investigated against Hepatoblastoma (HepG2) and Breast cancer (MCF7) cell lines by the MTT assay. The cytotoxicity has a positive relationship with the chitosan concentration. The half-maximal growth inhibitory concentrations (IC50) were 329 and 195 µg/ml with HepG2 and MCF7, respectively. Therefore, Chitosan may be a potential natural compound for the treatment of human hepatoblastoma (HepG2) and breast cancer (MCF7).

The objective of this study was to analyze the potential toxicity of the Hydroxyapatite. 60 male albino rats were treated with Hydroxyapatite for 30 days. Toxicity was monitored by quantitative analysis of the serum testosterone hormone level; follicle-stimulating hormone (FSH) level in serum, luteinizing hormone (LH) level in serum, prolactin hormone PRL) level in serum, AST activity and Alkaline phosphatase activity was measured and tests were collected for histopathological study. The results refer to a significant decrease in testosterone; FSH, LH and PRL while a significant increase in AST and ALP). Histopathology revealed moderate disturbance with an irregular cycle of spermatogenesis in seminiferous tubules, a marked decrease in the number of spermatogenic cells in the seminiferous tubules, a marked decrease in the number of sperms and Leydig cells. The administration of the Chitosan had beneficial and decrease side effects against the deleterious changes of Hydroxyapatite. In conclusion, results suggest a potential contribution of Hydroxyapatite to the etiology of somebody's diseases while Chitosan has beneficial effects as it tends to dampen Hydroxyapatite toxicity in rats.

In some regions of the Deltaic Mediterranean coastal land of Egypt, Baldratia salicorniae Kieffer, 1897 (Diptera: Cecidomyiidae) is a gall-forming insect that induces fleshy galls on the stem of Salicornia fruticosa (L.) L. (Family: Amaranthaceae). the current study tried to investigate the interaction of B. salicorniae with its host plant S. fruticosa in some regions of the Mediterranean coast and study the effect of altitude and vegetation cover on galls induction. In addition, to estimate the predicted geographic distribution habitats of B. salicorniae and its host plant S. fruticosa in Egypt by using MaxEnt technique.

Maggot therapy's success is partly due to the ingestion and killing of living microorganisms. The aim of this study was to investigate the antibacterial activities of maggots’ crude extracts (DMSO and PBS extracts) and excretion/secretion of Chrysomya albiceps (Diptera: Calliphoridae). The excretion/secretion (E/S) and crude extracts were collected from third larval instars of C. albiceps. The extracts were tested against Escherichia coli and Pseudomonous aeruginosa, as Gram-negative bacteria and Staphylococcus aureus and Bacillus subtilis as Gram-positive bacteria. Antimicrobial activity was done by calculating the reduction percentage of the colony's growth. The E/S was appeared the highest antibacterial activities against Gram-positive and Gram-negative bacteria, while the PBS extract has appeared the lower antibacterial activities. Generally, the E/S of C. albiceps maggot was found to be more effective as antibacterial agents than crude extracts (DMSO and PBS extracts).

In order to investigate the possibility of detecting host DNA isolated from larval crops and the effect of time elapse during digestion, the present study was carried out. Domestic pig cadaver was used as a case study model instead of real human corpse tissue by collecting of 3rd instar larvae post-feeding and starving during24, 48, 72, and 96 hours. The identification of DNA extracted from pig tissues and from Sarcophaga carnaria Linnaeus and Chrysomya albiceps Wiedemann larval crops fed on deceased pig remains were carried out using PCR. The detection of DNA bands in the larvae of the two dipteran species was carried out by using Gel electrophoresis. Results showed that the extracted DNA from larval crops of the two fly species was identical to that extracted directly from domestic pig decaying tissues. In addition, the PCR specifically amplified the domestic pig mtDNA cyt b gene with 203 bp amplicons. Results also showed that DNA could be clearly detected within approximately 72h after the removal of larvae from pig corpse, suggesting reliable consecration of insects as valuable evidence in crime scenes. These results are useful for further consideration of the estimation of postmortem intervals (PMI) by the aid of forensic entomology.

Industrial pollution is one of the most dangerous that is a continuous threat for humanity. Evaluation of that pollution is the main aim of the current study through the detection of the accumulated heavy metals in its surrounding habitats mainly soil and flora as well as the response of insects towards this pollution. Therefore, seasonal collection of three different insect species were performed in addition to soil and the common plant; Zilla spina, at different sites of El-Sadat industrial city, Menofia, Egypt for four successive seasons during 2016 to 2017. The Acetylcholinesterase (AChE) and lactate dehydrogenase (LDH) extracted from the homogenate of the chosen insects were used as biomarkers for heavy metals pollution. Also, heavy metal contents in plant and soil samples were analyzed. Results showed varied activities for the investigated biomarkers depending on the study sites, providing a representative picture to the environmental state of that areas.

The present study evaluated the activity of ethanol 70%, acetone, chloroform and petroleum ether extracts of Musa acuminata leaves against the 3rd instar larvae of the mosquito vector, Culex pipiens (Diptera: Culicidae) which act as a vector of many diseases in Egypt. In addition, the repellent activity of the tested extracts against C. pipiens adults was examined. The obtained results revealed that, all tested plant extracts showed a larvicidal activity against the 3rd instar larvae of C. pipiens; however, the petroleum ether extract was more effective with LC50 571.8ppm than chloroform, acetone and ethanolic extracts, where the LC50 values recorded 1567.3, 1158.3 and 1034.1ppm; respectively. On the other hand, all tested extracts evoked a variable degree of repellent activity against C. pipiens starved females. Also, petroleum ether extract was the most effective extract that exhibited high repellent action as compared with the chloroform, acetone and ethanolic extracts. These results demonstrated that ethanolic, acetone, chloroform and petroleum ether extracts of M. acuminata leaves serve as pest control agents, even in their crude form. These results provide an opportunity to develop alternatives to costly organic pesticides with some available cheap plants which are usually safe to the environment and to non-target organisms.

The use of family variation of aquatic insects in assessing freshwater quality in ecosystems has only recently been applied in the northern parts of Africa. The current study along with El Husseiny et al. (2015) and Bream et al. (2017) can be considered the first of such studies in Egypt. The survey was conducted during the period April 2015 to February 2016, in the permanent stream, El-Mansouriya, in Dakahlia province, Egypt. The water quality and health status of water for human use of this stream was determined using different aquatic invertebrate family biotic indices formulations (BMWP, SWRC and EPT indexes) along with the physical and chemical properties. Water samples were analysed and the water quality parameters were compared to the WHO (2004) standards. Most of the parameters were found to be within permissible limits, except for turbidity and nutrient salts. Aquatic insects were collected and identified to order and family levels. A total of seven orders and 19 families were collected, including a few intolerant insects (EPT orders) and insects more tolerant to pollution (chironomid larvae). The values of the water quality parameters sampled showed significant correlations with aquatic insect diversity. The canonical correspondence analysis clarified that the electrical conductivity of the water was the most significant variable affecting the variation in taxa. From these results it can be seen that the water quality of this stream is moderately impacted, and could therefore be considered harmful, since this stream is the main supply to the Water Central Station in Aga. Water quality degradation is generally due to impacts associated with population growth, industrialisation and agricultural activities. These results can be used to assist in conservation planning and decision-making in Egypt.

The house fly, Musca domestica L. is considered as a notorious pest by medical, veterinary, and public health professionals worldwide. This study was carried out to evaluate the effect of different entomopathogenic nematode (EPNs) strains against the 3rd larval instar and pupal stage of the house fly. Two of them were native strains (Heterorhabditis indica and Steinernema carpocapsae) and the others were imported strains Heterorhabditis bacteriophora and Steinernema glaseri. The results indicated that the mortality of all tested stages of M. domestica were significantly influenced by the infective juveniles (IJs) concentrations and the exposure time where the maximum mortality was recorded 72 hrs. post-treatment and the larvae were more susceptible to nematodes pathogenicity than the pupae. Also, the Heterorhabditis nematodes H. baceriophora and H. indica appeared to be more effective than the Steinernema species, and H. bacteriophora (Hb88) was the most promising strain in management of both larvae and pupae causing the lower LC50 and LC95 (320.4 and 1987IJs/ml) for larvae and (1414.6 and 2664.4 IJs/ml) for pupae, respectively.

Pesticides play a critical role in maintaining agricultural productivity, but intensive practice, repeated use and run off into the surface and ground water can pose a threat to the human and his domesticated animals. The study was carried out to identify the level of organochlorine pesticides and polychlorinated biphenyl residues in water wells using Limnatis nilotica leeches as bioindicators during summer and spring of the year 2013 at some localities of Al-Jabel Al-Akhdar, Libya. The chlorinated organic pesticide residues were ranged from 0.001 to 11.449 ng/g extracted from the whole homogenate body of leeches collected from five investigated wells. The obtained results showed that 100% of the analyzed samples contained detectable level of the monitored insecticides (HCH, aldrin, dieldrin, endrin, o،p-DDE, p،p-DDE, o،p-DDD, p،p-DDD and o،p-DDT). It is foundthat 100% of the samples gave results with levels below the MRL for HCH, aldrin, dieldrin, endrin concentration residues. Among all samples, 60% of the samples gave results with levels of total DDT concentration residues below the MRL, while 40% of the samples contained levels of insecticide residues above the MRL. On the other hand, there were occurrence of several polychlorinated biphenyl derivatives and 100% of the samples gave results above the level of the maximum contamination level for total PCB. The existence of total PCB at the highest levels were detected in Michael and El-Wasita wells at the summer season reaching 29 and 27 ng/g, respectively. However, the lowest detected level of total PCB reached (1.00) ng/g in leach tissues collected from Tiba well during summer season. The high levels of PCB derivatives detection in all leech samples is a health hazard reflected the continue uses of this materials source until this date and may be cause various diseases in Al-Jabel Al-Akhdar areas. Generally, the attained results emphasized that leeches are useful tools in biomonitoring of both organochlorine pesticides and polychlorinated biphenyl residues.

Marine gastropods are known to accumulate high metal concentrations in their tissues especially in the digestive glands. In this study, the accumulation of Cu, Zn, Cd, Cr and Pb in the gastropod Gibbula sp. (Family: Trochidae) has been assessed using Atomic absorption, spectrophotometry graphite Furnace. Animals were collected from rocky shores at Al-Hanyaa region on the north-east coast of Libya. Two groups of animals were studied; one from an area adjacent to a sewage outlet and the second was collected from a relatively clean site. Concentrations of metals in the viscera, of both adults and juveniles, of Gibbula collected from the polluted site were higher than that recorded in the clean site. Thus, there is a tendency for Gibbula tissues in the polluted area to have higher concentrations of metals although the differences are not always statistically significant. The values recorded for adult specimens collected from the polluted and non polluted locations were 0.51±0.27, 15.95±1.28, 0.021±0.017, 0.47±0.18, 0.60±0.17 vs 0.40±0.11, 9.51± 4.82, 0.03 ± 0.02, 0.29 ± 0.09, 0.39 ± 0.09 for Cu, Zn, Cd, Cr and Pb µg ⁄mg, respectively. Whereas, those recorded for juveniles were 0.51±0.09, 17.02±1.13, 0.032±0.01, 0.49±0.15, 0.54±0.17 vs. 0.38±0.22, 8.36±2.05, 0.020±0.01, 0.35±0.25, 0.52±0.12 for Cu, Zn, Cd, Cr and Pb µg ⁄mg, respectively. It is suggested that metals are taken up by Gibbula sp. viscera directly from the water or from the ingested algae. Also, the shell mass was affected with the pollution.