Cinnamon (Cinnamomum zeylanicum Blume) essential oil has vast potential as an antimicrobial but is limited by its volatility and rapid degradation. To decrease its volatility and prolong the efficacy of the biocide, cinnamon essential oil was encapsulated into mesoporous silica nanoparticles (MSNs). The characterization of MSNs and cinnamon oil encapsulated with silica nanoparticles (CESNs) was estimated. Additionally, their insecticidal activity against the rice moth Corcyra cephalonica (Stainton) larvae was evaluated. The MSN surface area decreased from 893.6 to 720 m² g⁻¹ and the pore volume also decreased from 0.824 to 0.7275 cc/g after loading with cinnamon oil. X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), and N2 sorption by Brunauer–Emmett–Teller (BET) confirmed the successful formation and evolution of the synthesized MSNs and CESN structures. The surface characteristics of MSNs and CESNs were analyzed by scanning and transmission electron microscopy. Compared with the sub-lethal activity values, the order of toxicity after 6 days of exposure was MSNs ˃ CESN ˃ cinnamon oil ˃ silica gel ˃ peppermint oil. The efficacy of CESNs gradually increases its toxicity more than MSN after the 9th day of exposure.

Photosensitizing compounds are eco-friendly promising organic dyes for managing insect pests without facing the risk of resistance. The photodynamic efficacy of four Photosensitizing compounds (rose Bengal, rhodamine B, methylene blue and methyl violet) was monitored against the third larval instar of Spodoptera littoralis (Boisduval), after exposure to sunlight. The LC₅₀ values of the four compounds; rose Bengal, rhodamine B, methylene blue and methyl violet recorded 0.029 × 10^–5, 0.24 × 10^–5, 14.69 × 10^–5 and 15.59 × 10^–5 M, respectively. Therefore, rose Bengal was the most effective compound followed by rhodamine B, Methylene blue and methyl violet. Compared to similar previously documented photosensitizer compounds, these four tested compounds recorded higher mortality percentage. The effect of those compounds on the larval biochemical components was assessed by measuring larval spectral and thermal reflectance. Larvae fed on photosensitizing compounds showed distinct spectral reflectance patterns. Treated larvae had same reflectance manner; which were higher than that of control samples. Along the whole spectrum, the highest reflectance was after 60 min of exposure to sunlight in case of rose Bengal, rhodamine B and methylene blue. Methyl violet reflected sunlight mostly at zero time then the reflectance decreased after 30 min then increased again after 60 min. There was a noticeable absorption of IR wavelengths at ~ 1900, 1400, 1200 and 950 nm in all treated samples. Thermal imaging indicated abnormal larval warmth after treatment. Differences in reflectance were monitored immediately after feeding, confirming the speed and mode of action of those compounds.

Background: One of the most important problems facing the silk industry in Egypt is the existence of a good hybrid that can withstand fluctuations in climatic change, which is the main reason for silkworm susceptibility to bacterial infection. Results: This study focused on the impact of feeding the silkworm larvae from the last day of the 3rd larval instar till the 1st day of the 5th larval instar on three species of lactic acid bacteria: Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus delbrueckii. Three different concentrations (10⁶, 10⁷, and 10⁸ CFU/ml) of each species were evaluated individually as treatment during the rearing season to reduce the expectation of diseases. The results indicated that each Lactobacillus sp. has improved the immune system of the silkworm, to some extent. Accordingly, treated larvae were more resistant to pathogens, as observed in low mortality records relative to control. Scanning electron micrograph of larval foregut revealed the association of Lactobacillus sp., as solitary and colonized bacterial cells, within crypts of the crop region and their attachment to its wall by biofilaments. Histochemical analysis of the silk gland at the end of the 5th larval instar showed great enhancement in fibroin and sericin production in treated silkworms with all tested probiotics, especially Lactobacillus acidophilus compared to untreated ones. Conclusion: Overall, incorporating Lactobacillus sp. into silkworm-rearing diets represents a hopeful strategy to boost their growth, health, and productivity, also fostering sustainable practices in sericulture.

Background: American foulbrood (AFB), Nosemosis and Varroasis are diseases that affect honey bee health and their products. The present study evaluated microencapsulated lactic acid bacteria (LAB) as a novel technique for the biocontrol of these diseases. Double coated microencapsulation was performed for the preservation of five different locally isolated, honey bee endogenous LABs (Lactobacillus plantarum MK780211, L. plantarum MK780215, L. kunkeei MK780216, L. kunkeei MK780218, and Lactobacillus sp. MK780212). Results: In vivo, twenty-seven colonies of honey bees of equal strength and queens of the same age were divided into seven treatments and compared with a control. There were different observations on the honey bee colonies according to their treatments. Honey bee colonies that were supplied with LAB microcapsules alternatively; with Fumidil®B and with formic acid had the highest increase in growth curves. The treatments that had a moderate increase in growth curves were the honey bee colonies treated with LAB microcapsules only and LAB microcapsules alternatively with Sulphamethoxazole, with Thymol, with both “Sulphamethoxazole and Thymol” and with both “Fumidil®B and Thymol”. Finally, honey bee colonies that were supplied with Sulphamethoxazole, Thymol, Fumidil®B and formic acid without LAB microcapsules (−ve control) had a slight increase in growth curves that was lower than normal. The honey bee colonies without any treatments (+ ve control) collapsed since the first three months of the experiment. Conclusion: Honey bee colonies could be supplemented with microencapsulated LABs, alternatively with low concentrations of traditional honeybee treatments such as Fumidil®B and formic acid to achieve maximum protection from diseases.

The development of a novel anti-stored grain pest membrane film of polyvinyl alcohol/chitosan-moringa nanoemulsion (PVA/CS-MNE) biofilm offers a promising alternative to conventional cereal packaging materials. The efficacy of different packaging films and thicknesses: polyethelene, cellophane, polypropylene, paper bags, and a prepared PVA/chitosan biofilm was evaluated for the control of Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae) adults. The estimated LC50 values for surface-treated PVA/chitosan biofilm, cellophane, polyethelene, paper bag, and polypropylene with moringa oil against T. confusum were 38.48%, 48.94%, 57.59%, 79.94%, and 125.06%, respectively. The most effective materials (PVA/chitosan biofilm, cellophane, polyethelene) were selected, and MNE was subsequently applied to these selected material types, resulting in LC50 values of 0.15%, 0.28%, and 0.47%, respectively. The results revealed that packaging materials treated with MNE exhibited higher toxicity compared to those exposed to moringa oil. Particle size and morphology of MNE, as measured by transmission electron microscope, confirmed the formation of spherical shape and uniform size with an average particle size around 90 nm. The zeta potential of -18 mV confirmed the formation of moderate stability colloidal system. Morphological changes were observed in a PVA/chitosan biofilm after moringa oil incorporation, as revealed by field emission scanning electron microscopy. A series of penetration tests conducted over 2 mo indicated that PVA/chitosan-MNE biofilm exhibited the highest protective efficacy. The numbers of exuviae, larvae, pupae, adults, and the percentage weight loss in packed wheat flour were 0.33%, 0.33%, 0.00%, 0.00%, and 0%, respectively.

Bioinsecticides have gained attention as a sustainable and eco-friendly alternative to traditional chemical insecticides. They are target-specific, biodegradable, and reduce the development of insect resistance. However, their use is often limited by environmental instability, particularly under sunlight and UV radiation, which rapidly degrade active ingredients and reduce efficacy. Protective formulation, such as addition of UV-screening agents are needed to improve their durability and efficacy. This study investigates the efficiency of three UV protectants, Octylpalmitate, Tinuvin P, and UV- P in enhancing the persistence of some biocontrol agents, Dipel DF, Tracer, and Diacox under field conditions for 15 days to control the 4th instar larvae of Spodoptera littoralis . After 12 days, the residual effect of the all insecticides had markedly decreased, with Tracer showing the lowest persistence with zero mortality, and Diacox + UV protectant the highest. By 15 days, the sustained efficacy was absent, except for Diacox mixed with Octyl palmitate, Tinuvin P, and UV-P, which still caused 27, 32 and 12% mortality; respectively. The SDS-PAGE of S. littoralis larvae following 15 days of treatments revealed differences in the numbers of protein fragments between treated and control. New protein bands formed in the treated samples, while several normal bands disappeared.