Overview of Research Progress and Current Utilization of Propolis
Propolis is @#@255@#@ a resinous substance collected by honeybees from tree buds, bark and other parts of plants, mixed with secretions from the bees' hypopharyngeal glands, wax glands and other glands, and processed and transformed by the bees. Propolis is an opaque solid, brown, reddish-brown or grayish-brown in color, sometimes with a greenish tinge, and in a few cases nearly black. Natural fresh propolis has a resinous fragrance and is sticky and malleable. It begins to soften at 36°C, becomes hard and brittle and can be pulverized at 15°C, and melts into a viscous liquid at 60-70°C. Propolis is a resinous substance, highly soluble in ether, chloroform, acetone, benzene and 2% NaOH solution, and soluble in 95% ethanol, forming a transparent solution, with granular precipitate separating out as the propolis concentration increases. The ethanol extract of propolis can reflect the quality and grade of propolis. The ethanol extract content of high-quality propolis is generally above 75%; 65%-75% is Grade 1, 60%-65% is Grade 2, 55%-60% is Grade 3, and below 50% is substandard.
1 Chemical Composition
Propolis basically consists of 50%-55% resins and aromatic oils, 30%-40% beeswax, and 5%-10% pollen. The compounds mainly include flavonoid compounds, organic acid compounds, esters, aldehydes, alcohol compounds, as well as alkene, hydrocarbon and terpene compounds. Among them, organic acid compounds have strong anti-pathogenic microorganism and liver-protective effects, and caffeic acid aromatic ester compounds have anti-cancer effects.
2 Pharmacological Effects
2.1 Anti-tumor effects: it has the effects of preventing colon adenoma and improving biochemical indicators during carcinogenesis, and acting against malignant glioma, melanoma and skin tumors.
2.2 Anti-pathogenic microorganisms: Propolis has an inhibitory effect on more than 20 kinds of pathogenic bacteria, including Staphylococcus aureus, Bacillus subtilis, Salmonella typhimurium, and upper respiratory tract infection bacteria; it can increase the synthesis of total serum protein in experimental animals, improve complement components, enhance the phagocytic function of macrophages, and improve the body's ability to resist pathogen invasion. The flavonoid compounds and 3-methyl-but-2-enyl caffeate in propolis have an inactivating effect on herpes simplex virus (HSV-1), adenovirus-5, influenza virus, rotavirus, stomatitis virus, etc., with a particularly obvious effect on HSV-1. 3-methyl-but-2-enyl caffeate can reduce the titer of HSV-1 virus, and the viral DNA synthesis capacity becomes 1/32 of the original.
2.3 Liver protection: Propolis extract has protective effects against carbon tetrachloride-induced liver injury, D-galactosamine-induced liver injury, and alcohol-induced liver injury. This protective effect is the result of the coordinated action of multiple active ingredients in propolis.
2.4 Immune regulation: Propolis can effectively enhance human immunity, promote the action of phagocytes, stimulate the body to produce antibodies, and resist a variety of diseases.
2.5 Antioxidant effects: The water extract, methanol extract and chloroform extract of propolis all have the effect of scavenging 1,1-Cipheny1-2-Picryhv-drazy1 free radicals and oxygen free radicals. The phenylacrylic acid derivative compounds isolated from the water extract have antioxidant effects stronger than Vc and VE.
2.6 Improving the cardiovascular system: Propolis contains a large amount of flavonoids (3.2 g of total flavonoids per 100 g), flavonols and other substances, and has a certain improving effect on the cardiovascular system.
2.7 Anti-ulcer effects: Studies have shown that propolis has the effect of promoting tissue repair, can reduce gastric acid in gastric ulcer model rats, counteract the formation of pyloric ligation-type ulcers, and counteract the formation of stress-type, alcohol-type and anti-inflammatory-type ulcers.
3 Clinical Applications
3.1 Oral diseases: Propolis has a long history of use in treating oral diseases in Western countries. In recent years, pharmacological studies have shown that propolis has varying degrees of inhibitory effects on salivary bacteria and streptococcal dental plaque. In treating oral ulcers, the pain relief effect is 100%; the smaller the ulcer surface, the faster the healing, with the fastest epithelial healing being 24 hours.
3.2 Cardiovascular diseases: In 160 patients with typical hyperviscosity syndrome, 50 drops of 30% propolis tincture were given orally before meals 3 times a day, while propolis tablets were also taken. Whole blood viscosity, plasma specific viscosity, erythrocyte sedimentation rate and hematocrit and other indicators were measured before and after administration, and the above indicators in plasma all showed significant differences. After taking the medication, patients' blood viscosity decreased, and they reported clear-headedness, agile reactions, disappearance of limb numbness, and increased physical strength.
3.3 Respiratory system diseases: Clinical trials show that propolis can significantly reduce the incidence of acute and chronic rhinitis in children, and also has a resistance effect against viruses and bacteria in the upper respiratory tract; in addition, propolis can also relieve cough and eliminate phlegm, treat colds with fever, dizziness, nasal congestion, dry and swollen painful throat, etc., has an anti-asthmatic effect on bronchial asthma, and has diaphoretic and anti-inflammatory effects.
4 Applications in the Food Industry
4.1 Natural preservative and freshness-retaining agent: Huang Jian reported that after spraying citrus twice with 10% propolis tincture, the fruit could be stored for 130 days, with a rotten fruit rate of 7.5%, 9.5% less than the control group, and a water loss rate reduced by 5.5%; coating poultry eggs with 10% propolis tincture could extend storage time by 2 times compared with no coating; in summer, poultry eggs coated with propolis could be kept for 60 days without spoiling, while uncoated ones showed yolk sticking to the shell and a slight off-odor after 20 days.
4.2 Natural antioxidant and preservative for meat products: Propolis water extract and alcohol extract were used for sausage preservation. 0.4% propolis water extract, 0.3% propolis alcohol extract and 0.28% potassium sorbate were respectively added to sausages, and the thiobarbituric acid value and volatile nitrogen in the sausages were measured at 1 week, 2 weeks, 3 weeks and 4 weeks respectively. The results showed that propolis water extract could significantly extend the shelf life of sausages.
5 Propolis Extraction: Crude propolis → freezing → pulverization → ethanol extraction → filtration → filtrate → vacuum concentration → propolis paste → low-temperature storage; filter residue → filtration → repeated extraction → vacuum concentration → ethanol recovery
5.2.1 Raw material selection and cold treatment: Select propolis of Grade 2 or above, and freeze it at -5°C for 5-6 hours to make it hard and brittle.
5.2.2 Pulverization and extraction treatment: The working environment of the ball mill should be below 15°C, and the pulverized particle size should be 20 mesh. During extraction, an ethanol concentration of 80% with a material-to-liquid ratio of 1:5 and extraction for 32 hours, or an ethanol concentration of 95% with a material-to-liquid ratio of 1:15 and extraction for 32 hours, can both achieve the highest extraction rate.
5.2.3 Filtration and vacuum concentration: After the propolis solution stands for 24 hours, filter it with a plate-and-frame filter, requiring the filter mesh to be above 400 mesh; then filter it with a diatomaceous earth filter or centrifugal separation filter to obtain a clarified propolis solution. Turn on the vacuum concentration pump to make the vacuum degree reach 66.7 KPa (500 mmHg) and the temperature inside the tank reach 145°C, recovering ethanol while concentrating the propolis solution. Note that the extract in the concentration tank must not exceed 2/3 of the container volume.
5.1 Process Flow
5.2 Key Operating Points
6 Consumption
Propolis is best taken on an empty stomach, and diabetic patients are advised to take it half an hour before meals. Infants and pregnant women should not take propolis, because the active ingredients in propolis can affect the normal development of an infant's immune system; after pregnant women consume propolis, certain bioactive substances can stimulate the uterus, cause contractions, and interfere with the normal growth and development of the fetus. Dosage: 0.8 g per day.
7 Main Products
7.1 Oral type: propolis tincture, oral liquid, tablets, capsules, emulsions, as well as chewing gum, propolis wine, and propolis honey.
7.2 Oral hygiene type: used for oral hygiene and health care, including propolis toothpaste, mouth rinse, aerosol, spray and mouthwash.
7.3 External use type: propolis cream, liniment, suppository, cream, lotion and acne liquid.
7.4 Cosmetics: propolis soap, skin care cream, perfume, growth lotion, spray hair cream.