shaghaygh rezanezhad

Some medicinal herb extracts have the antibacterial capability. On the other hand, herb extract is one of the organic, natural, and environmentally friendly substances. In recent years, the production of environmental and safe packaging materials has attracted the attention of scientists and industrialists. Paper is one of the biodegradable and less cost options for packaging in various industries, including the food industry. Also, the raw materials of paper can be modified and changed with different materials. As a result, paper fibers can be treated with herb extracts and used in the production of renewable papers with antibacterial properties.

In this research, thyme (Zataria Multiflora) was used for extraction. The thyme obtained from the research farm was dried and then powdered. Powdered thyme was treated via ultrasonication. In this method, two amplitudes of 40 and 60 amplitudes and three time levels of 3, 6, and 9 minutes were used for extraction. Then the papers were treated with herbal extract prepared in two amounts of 15 and 20% based on the dry weight of the paper by spraying. The antibacterial properties of the papers were investigated with Escherichia coli and Staphylococcus aureus bacteria. The chemical structure of materials extracted from the thyme extract investigated by fourier transform infrared spectrum (FTIR) analysis. Also, gas chromatography (GC-MASS) analysis was used to investigate the components of thyme extract. The optical properties of the paper, including brightness and opacity, and the strengths properties of the produced papers were measured by tensile, tear, and burst strengths.

The highest inhibition zone diameter in the treated paper with the thyme extracted by ultrasonic method was 20 mm in 40 amplitude and 9 minutes for Escherichia coli bacteria. Also, the highest inhibition zone diameter for Staphylococcus aureus bacteria was 14 mm in 60 amplitude and 6 minutes. According to the results of the papers analysis, the papers showed better antibacterial properties and higher inhibition zone against the Escherichia coli bacteria. The chemical compounds in the thyme extract including various substances such as hexane and furans. The most important chemical components that caused the antibacterial properties of the papers is carvenone, which was observed in the thyme extract. The results of the strength test of the treated papers showed that the sample of the thyme extracted by the ultrasonic method at 40 amplitudes, 3 minutes, and the 20% consumption amount based on the dry weight of the paper has the highest tensile and burst index. As well as, the highest tear index of the treated papers was in the treated sample with the thyme extracted at 60 amplitudes, 3 minutes, and 15% consumption amount based on the dry weight of the paper. The results of the optical tests showed that the opacity of the papers decreased and the brightness increased.

The results of this research showed that the paper as a biodegradable and environmentally friendly material has the ability to be treated with herbal and natural antibacterial materials such as the thyme extract. Also, the herbal extracts are a suitable alternative to inorganic and metallic materials in the production of materials with antibacterial properties due to the herbal extracts are cheap, available and natural materials.

Change in the food consumption’s pattern and the widespread use of the fast foods, as well as, the globalization of the food trade and the transportation of food over the long distances have brought great challenges to the safety and quality of the foods. One of the most important uses of the papers is the food packaging industry to keep the health and quality of the packaged materials from the production step to the customer. The extract of medicinal plants has the ability to create antibacterial properties. In this research, rosemary extract was used to produce the antibacterial papers. Extraction of plant was done by using soxhlet extractor and ultrasonic. In the soxhlet method, the dry powder was extracted at 4 and 6 hours and in the ultrasonic method, 40 and 60 powers were used for extraction. Then the papers were treated with plant extract prepared in two amounts of 15 and 20% based on the dry weight of the paper. The antibacterial properties of the papers were investigated with Escherichia coli and Staphylococcus aureus bacteria. All the papers treated with rosemary extracted by soxhlet method showed antibacterial property. Inhibition zone of bacteria was formed for both of them. The maximum diameter of the Inhibition zone for Escherichia coli and Staphylococcus aureus bacteria with 6 hours’ extraction and the consumption amount of 20% was 22 and 20 mm. In the treated paper with rosemary extracted by ultrasonic method, the maximum diameter of the Inhibition zone for Escherichia coli bacteria was 20 mm in 40A and 9 min. Also, the highest diameter of the Inhibition zone for Staphylococcus aureus bacteria was 20 mm in 40A and 9 min. Gas chromatography confirmed the presence of antibacterial substances including, Borneol, Camphor, and Bornyl acetate in rosemary extract