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Recently, there has been multi-agency promotion of entomophagy as an environmentally-friendly source of food for the ever increasing human population especially in the developing countries. However, food quality and safety concerns must first be addressed in this context. We addressed these concerns in the present study using the edible stink bug Encosternum delegorguei, which is widely consumed in southern Africa. We analysed for mycotoxins, and health beneficials including antioxidants, amino acids and essential fatty acids using liquid chromatography coupled to quadrupole time of flight mass spectrometry (LC-Qtof-MS) and coupled gas chromatography (GC)-MS. We also performed proximate analysis to determine nutritional components. We identified the human carcinogen mycotoxin (aflatoxin B1) at low levels in edible stink bugs that were stored in traditonally woven wooden dung smeared baskets and gunny bags previously used to store cereals. However, it was absent in insects stored in clean zip lock bags. On the other hand, we identified 10 fatty acids, of which 7 are considered essential fatty acids for human nutrition and health; 4 flavonoids and 12 amino acids of which two are considered the most limiting amino acids in cereal based diets. The edible stink bug also contained high crude protein and fats but was a poor source of minerals, except for phosphorus which was found in relatively high levels. Our results show that the edible stink bug is a nutrient- and antioxidant-rich source of food and health benefits for human consumption. As such, use of better handling and storage methods can help eliminate contamination of the edible stink bug with the carcinogen aflatoxin and ensure its safety as human food.

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Encosternum delegorguei Spinola (Hemiptera: Tessaratomidae) are consumed as relish and with traditional claims of having medicinal roles in the South-Eastern districts of Zimbabwe. However, very little has been explored scientifically to validate these claims. The current study was conducted to investigate bio-active compound composition and diversity of stable antibacterial activity from E. delegorguei extracts. Methanol, ethanol and aqueous extractions of E. delegorguei were performed followed by qualitative, quantitative analyses of phytochemical/bioactive compounds and determination of antibacterial activities using disc diffusion method on ten clinically important microbes. Alkaloids, flavonoids, anthraquinones, tannins, phlobatannins, steroids, triterpenoids and cyanogen glycosides were detected in the insect extracts. Flavonoids were detected in significantly higher concentrations in unprocessed compared to processed insects. Mean DPPH free radical scavenging activities were 78% and 88% for traditionally processed and raw insect extracts respectively. Traditional processing resulted in reduction of bioactive compounds (22.2% total phenolics; 68.4% flavonoids) and free radical scavenging activities by 10%. However, it resulted in an increase of cyanogen glycosides by 65.7%. Methanol extracts produced highest mean inhibition zones of 20 mm while aqueous and ethanol extracts had mean inhibition of 0 to 15 mm as compared to control with 20-40 mm. High flavonoids levels could be beneficial to consumers. However, a potential trade-off from elevated levels of cyanogen glycosides after processing needs further investigation. The free radical scavenging activity displayed by E. delegorguei extracts indicate a potential source of natural anti-oxidants that can be formulated into commercial products.

Edible insects are gaining recognition as food with potential of contributing to attainment of household food security. In sub-Saharan Africa, sustainable use of insects as food is threatened by lack of data on host plants and habitatassociations. In addition, lack of nutritional data on most edible insects reduces consumer confidence and limits integration of insect consumption with other food sources. This study was undertaken to review, collate and assembledispersed information of some edible insects of Zimbabwe. Data on species identities, host plants and habitats weregathered for 14 species from reputable literature sources and Bulawayo Natural History Museum records. In addition, nutritional assessments were carried out on 10 widely consumed insects in Zimbabwe. Standard ecological samplingprocedures were used to collect insect specimens. Proximate analyses were conducted following the Association of Official Analytical Chemists standard procedures using dried pulverised material. Majority (60%) of reviewedinsects had reliable host plants and habitats records. More than half of these were recorded in agro-ecosystems. On dry matter basis, protein content ranged from 22%(Gryllotalpa africana) to 55.4% (Gonimbrasia belina); fat content ranged from 10.8% (G. africana) to 41.6% (Macrotermes natalensis). Ash content was >10% in the ground dwelling G. africana (12.6%) and Eulopida mashona larvae (10.9%). Wide species differences were recorded for carbohydrate content; 0.4% in M. natalensis and 47.2% in G. africana. Carbohydrates content was inversely relatedto protein and fat contents for all insects. Energy and fat contents were positively related in all the insects. Overall, insect species from this study have high proximate constituents that can match plant and animal products diets andcan be considered as potential viable alternative nutritious food sources. Findings from this study are expected to promote greater recognition of insects as food in Zimbabwe and encourage up-scaling of their sustainable utilisation.

Pollination ecosystem service contributes tremendously to food security; however, little is known about the farmers' awareness of the ecosystem service to ensure conservation of pollinators. This study determined farmers' perceptions, knowledge, attitudes toward bees, and pollination in a maize-producing region of Zimbabwe using semistructured questionnaires (N ¼ 828). Generalized linear model and logit regressions were used to determine factors influencing farmers' ability to identify bees, knowledge of pollination, and fear toward bees, respectively. Identification of bees was positively related to education, years in farming, and negatively related to fear toward bees (p < .001). Fear toward bees was influenced by gender, knowledge of bee attack fatalities, and perception of the importance of bees (p < .001). The majority of respondents (67%) confirmed knowledge of pollination (v 2 ¼ 96.043, p < .001), and the probability of knowing pollination was higher for those who depended on media compared with extension and school education as a source of farming information (p < .001). Our findings suggest that to improve bee conservation, farmers should be made more aware of the diverse bee fauna, specifically regarding their benefits as pollinators compared with the few dangers (resulting from stings) in order to reduce fear and increase willingness to conserve bees. Bee awareness programs need to be accessible to women, youth, and those with less formal education as they exhibited the least knowledge. Our findings also support evidence showing that extension officers should consider various media options for the effective dissemination of information to the different target audiences.

Body size of herbivorous insects may be directly related to host plant characteristics (e.g. nutrition, chemical composition) and positively linked to performance of the herbivore and its parasitoids. Differences in adult body size of Liriomyza huidobrensis, L. sativae and L. trifolii reared on Pisum sativum, Phaseolus vulgaris, Vicia faba and Solanum lycopersicum were assessed to determine the effect of host plants on adult size. Furthermore, morphometric wing and hind tibia measurements were used to determine suitability as proxy measures for adult size. Based on canonical and linear discriminant analyses, two distinct Liriomyza morphospecies groups were recognized across all plant species. The first cluster represented L. huidobrensis and the second L. sativae and L. trifolii. The overall degree of correct classification of the three species across all plants tested (correct observation) with cross validation was estimated at 85%. Liriomyza huidobrensis, the largest species, showed no differences in the variables measured when reared on the four plant species. However, different plant species seem to influence wing and hind tibia measurements in L. trifolii to a greater extent than in L. huidobrensis and L. sativae. The first two canonical variates could not separate the populations of L. huidobrensis and L. sativae reared on different plant species, but showed separation of L. trifolii populations into two clusters: firstly, insects reared on V. faba and secondly, insects reared on P. vulgaris and S. lycopersicum. Hind tibia length strongly correlated with wing length. Both can be used to determine adult size of the three Liriomyza species. This study provides some new evidence for the existence of differential preferences by Liriomyza species for the four host plant species. This, therefore, warrants larger scale field studies to test for positive preference‐performance of Liriomyza species on these plant species and to determine possible consequences at the third tritrophic level.

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