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Background: Citrus aurantium essential oil was extracted from fruits collected from two regions namely Nabeul and Boussalem, characterized by diverse climatic and geographic conditions. Essential oils were investigated for their yield, chemical components, antioxidant and insecticidal activities against adults of the lesser grain borer Rhyzopertha dominica. Then, the essential oil that has the highest insecticidal activity was encapsulated into pectin:Gum Arabic and tested by fumigation against R. dominica adults. Additionally, emergence inhibition of their offspring was assessed. Methods: Pectin and essential oils were extracted from C. aurantium fruit peels by acid extraction chemical method and hydrodistillation, respectively. GC–MS analysis was used to identify the chemical components of the essential oils. Microcapsules were prepared at different ratios with various concentrations of pectin–Gum Arabic matrix. The encapsulation efficiency (EE %), loading capacity (LC %) and cumulative release (CR %) were determined using UV–Vis spectrophotometer. Crude and encapsulated Citrus aurantium essential oil in pectin–Gum Arabic-based microcapsules was tested by fumigation against adults of the lesser grain borer Rhyzopertha dominica for three storage durations (30, 60 and 90 days). Phosphine was used as conventional fumigant insecticide. Results: Results showed that microcapsules with pectin–Gum Arabic:Eo (0.5:2.5:1) was characterized by the highest EE (81.062%) and LC (5.79%). Fumigation tests revealed that encapsulated essential oil exhibited an effective control against R. dominica adults and their descendants during the three storage periods with 100% of mortality and emergence inhibition, compared to crude essential oil which generates 100, 90 and 60% of emergence inhibition, respectively after 30, 60 and 90 days of storage. Conclusion: Wastes from Citrus aurantium produce valuable products as pectin and rich limonene essential oils. Microcapsules based on pectin:Gum Arabic:essential oil could be utilized as an effective bio-insecticide for the control of insect pests in storage commodities. [ABSTRACT FROM AUTHOR]

The sunn pest Eurygaster integriceps Put. is one of the most economically important insect pests of grain crops in many countries all over the world. This paper presents an analytical review of the world literature devoted to the harmful activity of the sunn pest and its biological background, in particular, variation in grain damage by the pest and methods of its assessment. All the currently known methods of detecting grain damage by the sunn pest (including visual assessment, radiography, infrared microscopy, and the express scanning method) have certain disadvantages and require improvement. Infrared microscopy and computer scanning methods provide the highest accuracy combined with the greatest ease of use in identifying damage caused by the sunn pest. [ABSTRACT FROM AUTHOR]

Laboratory studies were conducted in order to assess the ability of Euphorbia balsamifera Aiton, Lawsonia inermis L., Mitracarpus hirtus (L.) DC and Senna obtusifolia (L.) Irwin and Bemeby in the protection of stored sorghum grains against damages caused by Sitophilus zeamais Motsch. Ten adult S. zeamais were introduced in 20 g of freshly harvested sorghum grains treated with 2.5, 5.0 and 10.0 × 104 ppm of powders and ethanolic extracts of the botanicals separately. The experiment was arranged in a completely randomized design (CRD) and replicated four times. The weevils were removed after 14 days leaving the grains only. All emerged adults were sieved and grain damage was assessed 84 days after treatment (DAT) while seed viability was determined after 6 months post treatment. Highest (10.00 ± 2.04 %) grain perforations (GP) was recorded in 2.5 × 104 ppm S. obtusifolia powder while 2.50 ± 1.44 % was the least GP recorded in 10.0 × 104 ppm E. balsamifera ethanolic extracts. Weight loss (WL) caused by the weevils due to their internal feeding as well as exit holes among the botanical treatments was high (4.16 ± 1.10 %) in 2.5 × 104 ppm S. obtusifolia powder, while it was low (0.89 ± 0.52 %) in 10.0 × 104 ppm E. balsamifera ethanolic extracts. Germination of treated sorghum varied between 77.50 ± 4.79 and 92.50 ± 2.50 %. The selected botanicals have shown considerable protectant ability to sorghum grains against S. zeamais infestations and could therefore be used while storing sorghum grains for seeds [ABSTRACT FROM AUTHOR]

Finger millet pearling process involves so many drudgery prone operations that specify the need for the development of finger millet pearling drum. The performance of pearling drum depends on its operational parameters. Therefore, this study aims to optimize the operational parameters of the pearling drum such as drum speed, concave clearance and pearling sieve size to obtain maximum pearling efficiency and minimum grain damage. The analysis was carried out using Response Surface Method along with the Box–Behnken Design tool. The optimum operational parameters were found as drum speed 7.25 m/s, concave clearance 3 mm and pearling sieve size 2 mm that predicts the maximum pearling efficiency of 98.95% and minimum grain damage of 0.73%. Finally, the performance of the pearling drum was validated setting optimum conditions. It results pearling efficiency of 99% along with 0.5% grain damage. Above results indicates that the validated pearling drum performance was better than predicted. [ABSTRACT FROM AUTHOR]

Storage pests cause considerable damage to stored grains in Eritrea. A study on storage pest control was conducted at room temperature (25 °C) and 57% relative humidity, to evaluate the efficacy of botanicals and sodium chloride (table salt) against Zabrotes subfasciatus Boheman on field pea (Pisum sativum L.). The experiment was conducted in a completely randomized design (CRD) in three replications. The treatments used were: neem (Azadirachta indica), red pepper (Capsicum frutescens L.), sesame (Sesamum indicum L.) oil, datura (Datura stramonium L.), eucalyptus (Eucalyptus globulus Labill), table salt (sodium chloride) and a control without pesticide. Data collected were weight loss, damage percent and germination percent of field pea grain, and also adult mortality of Z. subfasciatus. Rates of application for all the treatments were 3% w/w and an untreated control. Results of the study showed that E. globulus leaf powder caused 88.89% mortality of Z. subfasciatus and sesame oil caused 100% mortality, three days after treatment. The other treatments were less effective in causing mortality of the insect. After five months of storage, the lowest weight loss was observed in grain treated with sesame oil (1.81%) and neem (4.02%) compared with the control that had 16.68% loss. Grain weight loss was 7.45% for treatment with table salt, 8.11% for eucalyptus, 9.62% for red pepper and 15.29% for datura. Grain damage and weight loss increased as storage time increased. Moreover, these plant materials and table salt had no effect on the germination capacity of field pea. In general, the results obtained indicate that these plant materials and table salt can be used for the control of Z. subfasciatus. [ABSTRACT FROM AUTHOR]

This paper describes the grain damage characteristics of a grinding wheel with laser-brazing and discusses its relationship to the normal grinding force during the face grinding of granite. The results of our experiment show that the primary wears patterns of the brazed diamond grinding wheel in the whole grinding process are whole, wear-away, micro-fractured, and macro-fractured. There is no type of falling-off for the diamond grinding wheel, so the result indicates that it is possible to braze the diamond grits through appropriately manipulating the parameters of the laser. During the grinding process, the diamond shapes cause grinding forces to vary, and these variations actuate the transformation of the diamond shapes. The results obtained in this paper provide a reference for researching the wear mechanism of diamond grains, for optimizing grinding parameters, and for consummating the manufacture of laser brazed diamond tools. [ABSTRACT FROM AUTHOR]

Enzymatic unhairing is a cleaner strategy for leather-making. It is a potential alternative to the traditional hair-burning process. However, several shortcomings, such as uncontrolled enzymatic reaction, and risk of grain looseness and damage have restricted the broad application of enzymatic unhairing. In this work, metal ions and organic additives were screened for lessening the hydrolytic activity of proteinase K to collagen fiber. Then, the selected additives were applied to the enzymatic unhairing process for bovine hide. The results showed that a suitable concentration of metal ions (Cu (II), Fe (III) and Al (III)) and organic additives (salicylate, laurate, adipate, gallate and epicatechin (ECG)) could diminish approximately 35% of the hydrolytic activity of proteinase K to collagen fibers. Then, the additives were applied for the bovine hide enzymatic unhairing process. Hydroxyproline determination in the unhairing float shows that applying additives could reduce collagen hydrolysis. The morphology results showed that the grain damage could be significantly reduced with the addition of the screened additives in the proteinase K enzymatic unhairing system, whereas the addition of ECG and gallate significantly slowed down the unhairing speed. This outcome provides new potential to reduce the risk of grain damage in enzymatic unhairing process. [ABSTRACT FROM AUTHOR]