Impressive Impact of Hemp Extract on Antioxidant System in Honey Bee (Apis mellifera) Organism
Patrycja Skowronek, Aneta Strachecka, Łukasz Wójcik.Department of Invertebrate Ecophysiology and Experimental Biology, University of Life Sciences at Lublin, Doświadczalna 50a, 20-280 Lublin, Poland
We examined the effect of hemp extract on the activity of the antioxidant system (catalase, peroxidase, glutathione, superoxide dismutase, and total antioxidant capacity) in the hemolymph of adult honey bees (Apis mellifera). The bees were divided into three groups: (1) an experimental group fed with pure sugar syrup with cotton strips soaked with hemp extract put inside the cage; (2) an experimental group fed with a mixture of sugar syrup with hemp extract; and (3) a control group fed with a mixture of sugar and a water–glycerine solution. Hemolymph samples were collected on the 1st day of this study and then every week, until all bees in the group died. The activities of all antioxidant enzymes were higher for the experimental groups, compared to those for the control group. The highest antioxidant activities were noted in the group supplemented with cannabis with the use of syringes. Supplementation with hemp also increased the lifespan of bees in this group compared to that of the bees consuming only sugar syrup (control: 35 days), with 49 and 52 days for groups of cannabis on strips and in syrup, respectively. Hemp extract, thanks to its antioxidant properties, increased the activities of key antioxidant enzymes that protect the bee’s organisms against free radicals and thus delay the aging processes.
CBD Supplementation Has a Positive Effect on the Activity of the Proteolytic System and Biochemical Markers of Honey Bees (Apis mellifera) in the Apiary
Patrycja Skowronek, Aneta Strachecka, Łukasz Wójcik. Department of Invertebrate Ecophysiology and Experimental Biology, University of Life Sciences at Lublin, Akademicka 13, 20-950 Lublin, Poland
The purpose of our study was to determine how CBD extract influences resistance in the hemolymph (insect blood) of honey bees in the hive test. The bees were divided into 3 groups: (CSy) bees fed with CBD in sugar syrup; (CSt) cotton strip with CBD placed in hive, (C) control bees fed sugar syrup. To determine the state of immunity, we used the analysis of the activity of the proteolytic system and biochemical markers, such as “liver tests”, and the concentration of selected ions and key compounds for the functioning of the organism. CBD extract increased the total protein concentration, proteases and their inhibitor activities in each age (except for acidic protease activities in the 21st and 28th day and alkaline protease inhibitor activities in the 28th day in the CSt group), increased concentrations of markers: ALP, AST, ALT; and glucose; triglycerides; cholesterol and creatinine. A decrease in concentration in experimental groups was noticed for urea acid and albumin compared to group C. Higher activities/concentrations of most of parameters were obtained in the CSy compared to the CSt and C. The CBD supplementation can positively influence bees’ resistance.
Hemp products as a strategic tool in combating Varroa destructor mites and protecting and strengthening bee colonies.
Natural-origin products are safe for both beekeepers and bees, while effectively combating varroa mites and boosting bees' immune parameters.
Research into the effects of various hemp products and their active compounds on bees has shown positive impacts on their health and immune response. Notably, hemp extract can significantly enhance the antioxidant system in honey bees (Apis mellifera), boosting the activity of key antioxidant enzymes and, as a result, delaying aging processes in these insects. In the study by Skowronek, Wójcik, and Strachecka (2022), the use of hemp extracts demonstrated that supplementation, as an additive to sugar syrup or directly on material strips, extended the lifespan of bees compared to those consuming only sugar syrup. Another study by the same authors in 2021 also demonstrated the immunostimulatory effects of the previously tested product. The feeding of bees with hemp extract in the form of a hemp paste mixed with sugar syrup resulted in increased protein concentrations and positive changes in proteolytic system activities, indicating enhanced individual (physiological) immunity in the bees fed with the hemp product (Skowronek, Wójcik, and Strachecka 2021). These studies suggest that selected and tested hemp products may positively impact bee health, improving their longevity and immune response.
During a two-year study conducted at the Beekeeping Department of the Wrocław University of Environmental and Life Sciences, the effectiveness of the patented hemp preparation Varroa Kit in combating varroa, one of the most dangerous diseases of bee colonies, was confirmed. Untreated varroa weakens bee colonies, leading to a significant decrease in productivity and, in extreme cases, colony collapse (Chorobiński 2010). The hemp preparation caused partial or total paralysis of mites (leading to death). Sticky or oil-covered bottom inserts should be used during the application of the preparation to prevent paralyzed parasites from returning to the hive frames. The recommended method of application involves using standard-sized medicinal bee strips, placed between the second and third frames on opposite sides in a 10-frame hive. When hive space was smaller, strips were hung on the last frames with brood. The product was administered twice during the beekeeping season (early spring and summer). The withholding period for the strips was only 7 days, allowing the product to be used during honey harvesting. No residues of the preparation were detected in bee products, indicating no transfer of the substance to honey, bee bread, or propolis.
Hemp extract (Cannabis sativa L.) in beekeeping
Hemp extract (Cannabis sativa L.) has gained significant popularity in recent years, finding applications across various sectors, including agricultural production. Ongoing research continues to reveal its new properties and potential uses. One of the promising research avenues explores the extract's application in beekeeping. The method of extracting the substance from hemp – whether from the whole plant or different parts – determines its composition and properties. Of the 100+ compounds present in the extract, key ingredients include cannabinoids, flavonoids, plant sterols, fatty acids, and terpenes. These compounds work in synergy – the secret of the product lies in its rich combination of substances.
Beyond its broad spectrum of applications, it is worth emphasizing that the extract is a natural product. The properties of the hemp extract have demonstrated a wide-ranging health benefit for bee colonies. Research has shown a positive impact of the extract on the honeybee organism. Depending on the presence and activity of active compounds in the extract, as well as its quality and purity, the dosage is tailored as a dietary supplement for bees. At the University of Life Sciences in Lublin, it was found that the extract stimulates the bees' immune system by enhancing the activity of proteolytic and antioxidant enzymes (e.g., SOD, CAT, GST), as well as enzymatic (ALT, AST, ALP) and non-enzymatic (e.g., glucose, triglycerides, or ions of certain minerals) biochemical markers. These compounds are indicators of the physiological condition of the insect. In laboratory conditions, this resulted in an extended lifespan of worker bees compared to those not exposed to the extract.
The pharmacological activity of the extract depends on the method of application. Most often, it is administered orally to the bees. One highly effective method involved using strips soaked in the extract, a technique independently proposed by the University of Life Sciences in Lublin (detailed in DOI publications: 10.3390/antiox12020279; 10.3390/ani11082190; 10.3390/antiox11040707; 10.3390/ani12182313) and the Beemmunity company for testing in the “Innovation Voucher” project. This method allows for a prolonged effect of the active substances and, importantly, is easy to apply for beekeepers. Notably, exceeding the recommended dose in this form of application did not increase mortality among worker bees (in cage tests), indicating that the hemp extract is safe for bee colonies. In contrast, spraying bees with the extract yielded unsatisfactory results, leading to increased mortality, likely due to excessive amounts of the preparation settling on the insects.
Bee colonies face numerous harmful factors, including environmental pesticides, heavy metals, certain frequencies of electromagnetic fields, residues or metabolites of mineral fertilizers, and diseases. Research on the use of a hemp-based product called BeeLife, containing hemp extract, conducted both in laboratory and apiary conditions, showed a positive impact on bees. The studies were carried out at the educational and research apiary of the University of Environmental and Life Sciences in Wrocław, as part of the “Innovation Voucher” project. Forty bee colonies received strips soaked with the preparation at a specified concentration. The impact of the preparation on the bees was assessed based on measurements of brood and bee bread surface on the comb (cm²), propolis production, honey, and pollen yield. The condition of the bee colonies was monitored before and after wintering. Additionally, the level of infestation by the Varroa destructor mite and the bees' reaction to the placement of the strips in hives were evaluated. The application of the preparation did not negatively affect any of the evaluated parameters. Exposure to hemp oil in strip form did not provoke any adverse reactions in the bees. The product did not increase aggression or cause the loss of queen bees, confirming its safety for bee colonies.
Following the exposure of bees to hemp oil, samples of propolis, honey, bee bread, and pollen were collected to check for the presence of extract residues. Samples were taken from colonies where the preparation was used in spring (April) in both May and September. In February/March, winter debris or live bees were collected, as well as honey, bee bread, and propolis, if available. Analysis of the collected material for the detection of BeeLife extract residues was performed using liquid chromatography (HPLC). The laboratory analyses helped determine the optimal composition of the preparation. Next, the penetration of the preparation into bee products was examined. Each sample (bees, honey, bee bread, propolis) was tested at least three times, twice during the season (when bees were foraging). No residues of the administered preparation were detected in the tested products. The laboratory results, therefore, suggest that the product does not penetrate bee products and does not contaminate them. The honey collected from the colonies was also subjected to a sensory evaluation by consumers, who assessed whether there were any changes in taste, aroma, or texture. According to the evaluators, the preparation did not affect the sensory qualities of the honey.
The results are very promising and suggest that the preparation can be used to support beekeepers in maintaining the good health of bee colonies. Several factors must be considered when using and storing the preparation. It should not be exposed to direct sunlight for extended periods. The strips' packaging must remain tightly sealed and only be opened just before use. Care should be taken to prevent the strips from drying out or becoming overly humid. These factors significantly impact the effectiveness of the preparation and the results achieved. Therefore, when applying the preparation, avoid hot days and extended periods of rain. Too rapid evaporation of the active substances may reduce the effectiveness of the strips, while excessive moisture may reduce the concentration of active ingredients, weakening their impact.
The hemp oil preparation in strip form can be effectively used in beekeeping to help bee colonies combat environmental stressors, including Varroa destructor. One of the key issues examined in field studies was the impact of the preparation on the level of infestation by Varroa destructor mites. To this end, bee colonies were divided into experimental and control groups. Strips with oxalic acid were used as a reference product. The classification of bee colonies into appropriate groups was based on the number of mites found in brood, natural mite fall, and the results of a powder test. It was found that the preparation reduced the level of Varroa destructor infestation in the experimental colonies.