High Eugenol Content Research Articles

Evaluation of ten plant-derived biocides for the inhibition of photosynthetic organisms on the karst surfaces of heritage buildings

Biodeterioration is a significant problem in the conservation of stone heritage buildings. In this study, 10 plant essential oils were assessed for their effectiveness in biofilm inhibition on stone heritage building surfaces under laboratory and in situ conditions, and were compared with traditional biocides such as benzalkonium chloride. The plant extracts were tested against algae and mosses. The effect on algae removal was evaluated by measuring the color of the surface before treatment, after 24 h and after 1 month of treatment. The effect on mosses was assessed by measuring the photosynthetic pigment content of mosses after 24 h of treatment. The results showed that the different plant extracts exhibited different levels of antibiotic activity. Benzalkonium chloride, S. aromaticum and C. cassia extracts showed strong antibiotic activity against all algae and mosses tested. T. mongolicus extracts showed antibiotic activity against only some of the algae and mosses, while the application of P. cablin extracts increased chlorophyll b content in the mosses. The other plant extracts were less effective at inhibiting the growth of algae and mosses. GC–MS compositional analysis further indicated that the higher antibiotic activity of S. aromaticum and C. cassia extracts was related to the high content of eugenol and cinnamaldehyde.

Herbal Anti-fungal Cream: A Natural Approach to Onychomycosis Treatment

Abstract: Onychomycosis is a frequent fungal infection of the nails that is difficult to cure and is not well controlled by standard medications, therapeutic options are limited. Herbal remedies have drawn interest as a result of this due to their potential as complementary therapies. The composition and effectiveness of a novel herbal anti-fungal cream that combines the powerful anti-fungal qualities of clove oil, turmeric, and pure peppermint are examined in this abstract. The strong anti-fungal properties of clove oil's high eugenol content are enhanced by curcumin, an anti-inflammatory and anti-microbial compound found in turmeric. Pure peppermint contributes antifungal and calming qualities as well as a pleasant element. The combination of these components offers a viable way to cure onychomycosis, possibly more effectively than conventional therapies because it is allnatural.

Exploring the potential of chewing gums containing plant extracts (clove, saffron, and clove-mint) as a natural solution for controlling obesity and associated health issues

Background:Obesity is a global health concern resulting from an excessive accumulation of fat in the body, affecting individuals of all ages, including children. Modern lifestyles and the consumption of high-calorie foods have resulted in an increase in obesity prevalence. Cardiovascular disease, diabetes, blood pressure, and certain cancers are all serious health problems that obesity can lead to.Objectives: Medicinal properties in functional foods are gaining popularity in the food industry for controlling or inhibiting diseases. Given the growing concerns about obesity and its associated health risks, the need for natural compounds with controlling or inhibiting properties is paramount. This study aimed to explore natural plant extracts for their functional properties, particularly their ability to control obesity by inhibiting lipase enzyme. To transport these biological compounds, chewing gums containing extracts of cloves (at concentrations of 0.1%, 1%, and 3%), saffron, and mint were developed. Chewing gums containing extracts can become a popular natural remedy for a variety of health problems, including obesity. Using an effective delivery system, this solution is widely available to those looking for natural alternatives to address their health concerns.Methods: The research centered on exploring the properties of natural plant extracts, which included their potential to inhibit enzymes linked to obesity and related diseases, their antioxidant properties to counteract the harmful effects of body fat oxidation, and their antibacterial properties. In addition, the research involved a sensory evaluation of chewing gum that contained these extracts.Results: Clove extract had the highest amounts of total phenolic compounds. Also, clove extract exhibited the highest antioxidant properties and Helicobacter pylori inhibition (88.05% and 25.69% at ratio of 0.7% respectively), which is thought to be associated with its high content of eugenol and other phenolic compounds. Furthermore, the extracts were evaluated for other functional properties, including their ability to inhibit pancreatic lipase, angiotensin converting enzyme (ACE), and microbial activities against Streptococcus faecalis and Candida albicans. Among extracts, saffron extract showed the highest lipase inhibitory properties (40.07, and 36.06% at concentrations of 0.7% and 0.5% respectively). Also, clove and mint showed pancreatic lipase inhibition about 31.50% and 29.24 % at concentration of 0.7 and 0.5% respectively, revealing that all extracts can be a good candidate to be used as effective additives in preventing and controlling obesity. Also, clove, mint, and saffron extracts could inhibit blood pressure enzymes (25.54, 20.70, and 19.61 respectively), which can help maintain healthy blood pressure levels. Furthermore, release kinetics of extracts from chewing gums were obtained, and shown that after 20 min the release of extracts were 73.24, 64.34, and 63.2 for saffron, mint, and clove (1%) respectively.Conclusions: Extracts were found in our research to have a beneficial effect on controlling obesity. These compounds may be effective in preventing obesity, based on their observed inhibition of pancreatic lipase enzyme. However, further research is necessary to fully comprehend the efficacy of these substances for this purpose. The significant antioxidant properties of clove may have a promising impact on reducing free radicals, which can help prevent fat oxidation in the bodies of individuals with obesity. The inhibition of ACE enzyme by extracts could potentially have a positive impact on controlling blood pressure. The extracts showed potent antimicrobial properties that can potentially alleviate mouth and throat issues associated with Streptococcus bacteria. Moreover, extracts demonstrated efficacy in reducing the presence of H. pylori, which is the causative agent of stomach infections. Also, it was shown that chewing gum can be a convenient and easily accessible means of delivering natural compounds and may be a desirable option for individuals seeking natural alternatives for managing their health concerns.Keywords: Chewing gum, Plant extracts, Obesity, Blood pressure, H. pylori infections

Exploring the potential of chewing gums containing plant extracts (clove, saffron, and clove-mint) as a natural solution for controlling obesity and associated health issues

Background:Obesity is a global health concern resulting from an excessive accumulation of fat in the body, affecting individuals of all ages, including children. Modern lifestyles and the consumption of high-calorie foods have resulted in an increase in obesity prevalence. Cardiovascular disease, diabetes, blood pressure, and certain cancers are all serious health problems that obesity can lead to.Objectives: Medicinal properties in functional foods are gaining popularity in the food industry for controlling or inhibiting diseases. Given the growing concerns about obesity and its associated health risks, the need for natural compounds with controlling or inhibiting properties is paramount. This study aimed to explore natural plant extracts for their functional properties, particularly their ability to control obesity by inhibiting lipase enzyme. To transport these biological compounds, chewing gums containing extracts of cloves (at concentrations of 0.1%, 1%, and 3%), saffron, and mint were developed. Chewing gums containing extracts can become a popular natural remedy for a variety of health problems, including obesity. Using an effective delivery system, this solution is widely available to those looking for natural alternatives to address their health concerns.Methods: The research centered on exploring the properties of natural plant extracts, which included their potential to inhibit enzymes linked to obesity and related diseases, their antioxidant properties to counteract the harmful effects of body fat oxidation, and their antibacterial properties. In addition, the research involved a sensory evaluation of chewing gum that contained these extracts.Results: Clove extract had the highest amounts of total phenolic compounds. Also, clove extract exhibited the highest antioxidant properties and Helicobacter pylori inhibition (88.05% and 25.69% at ratio of 0.7% respectively), which is thought to be associated with its high content of eugenol and other phenolic compounds. Furthermore, the extracts were evaluated for other functional properties, including their ability to inhibit pancreatic lipase, angiotensin converting enzyme (ACE), and microbial activities against Streptococcus faecalis and Candida albicans. Among extracts, saffron extract showed the highest lipase inhibitory properties (40.07, and 36.06% at concentrations of 0.7% and 0.5% respectively). Also, clove and mint showed pancreatic lipase inhibition about 31.50% and 29.24 % at concentration of 0.7 and 0.5% respectively, revealing that all extracts can be a good candidate to be used as effective additives in preventing and controlling obesity. Also, clove, mint, and saffron extracts could inhibit blood pressure enzymes (25.54, 20.70, and 19.61 respectively), which can help maintain healthy blood pressure levels. Furthermore, release kinetics of extracts from chewing gums were obtained, and shown that after 20 min the release of extracts were 73.24, 64.34, and 63.2 for saffron, mint, and clove (1%) respectively.Conclusions: Extracts were found in our research to have a beneficial effect on controlling obesity. These compounds may be effective in preventing obesity, based on their observed inhibition of pancreatic lipase enzyme. However, further research is necessary to fully comprehend the efficacy of these substances for this purpose. The significant antioxidant properties of clove may have a promising impact on reducing free radicals, which can help prevent fat oxidation in the bodies of individuals with obesity. The inhibition of ACE enzyme by extracts could potentially have a positive impact on controlling blood pressure. The extracts showed potent antimicrobial properties that can potentially alleviate mouth and throat issues associated with Streptococcus bacteria. Moreover, extracts demonstrated efficacy in reducing the presence of H. pylori, which is the causative agent of stomach infections. Also, it was shown that chewing gum can be a convenient and easily accessible means of delivering natural compounds and may be a desirable option for individuals seeking natural alternatives for managing their health concerns.Keywords: Chewing gum, Plant extracts, Obesity, Blood pressure, H. pylori infections

Piper betel - Not Just a Mouth Freshener But Also a Miraculous Herb for Healing: A Review

Piper betle L., often known as betel vine, is a member of the Piperaceae family and is a significant cash crop for both economic and therapeutic purposes. The betle vine is most likely from Malaysia, while it is also grown in India, Sri Lanka, Bangladesh, Myanmar, and Nepal. It is grown in the districts of Balasore, Jagatsinghpur, Puri, Khordha, and Ganjam along Odisha's coast. With tremendous potential for creating jobs and improving the socioeconomic situations of rural people in India and other Asian nations, betel vine has enormous economic, medical, and nutraceutical value. However, there are still a number of significant elements of these plants that have not received enough consideration. Over a million people in Odisha use paan, yet most are not aware of its superior nutritional value. The most common chewing combinations for Piper betel include sliced areca nut, slaked lime, coriander, aniseed, clove, cardamom, sweetener, and coconut scrapings. Along with its traditional uses, Piper betel's therapeutic characteristics have the power to treat a variety of illnesses and lessen mouth cancer, which is actually brought on by sliced areca nuts and slaked lime rather than betel leaves. Betel leaves are a great source of vitamins, minerals, phytochemicals, antioxidants, protein, lipids, fibre, calcium, iron, and many other nutrients. Many research studies on Piper betle have reported that it contains important chemical constituents such as chavibetol, chavibetol acetate, caryophyllene, allylpyrocatechol diacetate, campene, chavibetol methyl ether, eugenol, a-Pinene, f-Pinene, u-Limonene, saprobe, 1-8-cineol, allylpyrocatechol monoacetate etc. Betel leaf is one of nature's best medicines and is thought to be superior to medications. Additionally, the leaves retain an essential oil (EO) with a high eugenol content (1-3%), which is a popular ingredient in medicines, stimulants, antiseptics, tonics, and other ayurvedic formulations. The demand for its goods, such as herbal medications, treatments, and natural herbal formulations, has grown recently. Additionally, Piper betel aids in the treatment of a wide range of illnesses, including rheumatism, diabetes, hypertension, halitosis, boils and abscesses, obesity, voice issues, conjunctivitis, constipation, headache, itches, mastitis, mastoiditis, leucorrhoea, otorrhoea, ringworm, gum swelling, and many others. The botanical description, geographic distribution, economic worth, cultivation, and ethnobotanical use of P. betle are all succinctly summarised in the current paper. According to the research, P. betle is a naturally occurring, safe, and orally active drug with significant therapeutic potential for treating a range of human medical disorders. To better understand its underlying molecular mechanisms of action, clinical features, structure-activity connections, bioavailability, and synergistic interactions with other medications, more research is still required.

Repellent Activity Test Of Essential Oil Gel Of Cinnamommum Burmanii Bi Leaves Against Aedes Aegypti Mosquitoes

Cinnamomum burmanni BI leaf is known to have high eugenol content, eugenol able to resist the bite of Aedes aegypti mosquito as a vector of Dengue Hemorrhagic Fever. Research on test of repellent activity of gel oil Cinnamomum burmanni BI leaf to Aedes aegypti mosquito is done to know its activity as a repellent preparation against Aedes aegypti mosquito. In this research made the gel of essential oil of Cinnamomum burmanni BI leaf with base karbopol 940 made in 3 formula, F1 (7,50%); F2 (15,00%); F3 (30,00%) and use Positive Control repellent supply on the market and contains DEET. The three formulas produce a good gel in terms of physical stability, organoleptic, homogeneity, pH, viscosity, and scattering, but all formulas cause irritation. The test of repellent activity against Aedes aegypti mosquito done for 4 hours with 5 repetitions showed Cinnamomum burmanni BI leaf oil formula F3 (30,00%) had repellent activity against Aedes aegypti mosquito with high protection 94,01% for 4 hours.

Biocontrol of root rot in Geranium with antimycotic rhizobateria

Excessive and frequent usage of synthetic fungicides has negative effects on the environment and human health. Biological control is one of the most efficient and environmentally responsible ways to manage plant diseases. In the present study, Bacillus velezensis strain B63, Bacillus subtilis subsp. Spizizenii strain TRC-20S and Serratia sp. Showed antifungal activities against Fusarium semitectum (synonym: Fusarium incarnatum), Macrophomina phaseolina, and Efibula tuberculata (MW063610) (synonym: Phanerochaete tuberculata). These fungi were isolated and purified from rotten geranium roots. M. phaseolina and F. semitectum were identified based on morphological and microscopic features. In addition, E. tuberculata was identified using the PCR technique. Bacillus velezensis strain B63 gave the best results in the terms of a decrease in plant mortality percentage and an increase in the geranium biometric parameters either under greenhouse or under field conditions. In addition, Bacillus velezensis strain B63 successfully increased the activity of defense-related enzymes, peroxidase (POD), and superoxide dismutase (SOD) and boosted the accumulation of total phenolic and flavonoid content in geranium leaves under field conditions. Also, the maximum essential oil yield with the highest eugenol content was recorded due to the application of B. velezensis and B. subtilis. Furthermore, anatomical analysis confirmed the positive role of biological control to induce resistance to root rot diseases through increasing root diameter, cortex thickness, vascular cylinder dimension, mean xylem vessel diameter, and xylem vessel number. Bacillus velezensis strain B63 possesses a broad expanse of antifungal and plant growth-promoting properties and can therefore play a vital role in boosting sustainable agriculture. This strain could be developed and applied in field experiments to improve plant growth and control root rot pathogens.

Eco-friendly self-polishing antifouling coating via eugenol ester hydrolysis

Ships and underwater facilities suffer from marine biofouling, which causes great harm. The most effective method against biofouling is to use self-polishing antifouling coatings. However, traditional coatings achieve antifouling performance by releasing toxic heavy metal antifouling agents, causing ecological problems. To solve this contradiction, a self-polishing antifouling coating polymer based on eugenol methacrylate was prepared. The hydrolysis of phenolic ester group realizes the transformation of resin segment from hydrophobicity to hydrophilicity. The self-polishing process releases eugenol, which is natural and non-toxic into seawater. It is the first time when self-polishing coating polymer achieves self-polishing by hydrolysis of phenolic ester groups and release of natural phenolic products. Eugenol release rate was the fastest at the beginning of immersion of the coating, reaching 0.48 μg·cm−2·day−1 for EMFP-25. After immersion in artificial seawater for 15 days, the release rate of eugenol from the coating tends to be stable, and the EMFP-25 with the highest release rate can reach 0.14 μg·cm−2·day−1. The resin has good antibacterial and anti-algae properties, and the mussel attachment experiments show that mussels have a tendency to avoid resin coatings with high eugenol content.

Application of TRIZ to modify oven drying for SMEs to maintain the eugenol content in dried cloves

Clove essential oil (EO) has a high eugenol content. Fresh cloves need to go through a drying and distillation process to produce essential oils. However, sun drying cannot be done optimally during the rainy season. Therefore, some farmers (SMEs) use the oven drying method. The initial study found that the eugenol content after the drying process decreased. Therefore, this study aimed to maintain high eugenol content in dry cloves. After identifying the problem, it is solved using the TRIZ method, and research is continued for a new oven prototype. Three issues are found in drying cloves based on field surveys and literature studies. First, the clove moisture content is not uniform after the drying process. The second problem was that the clove was too dry after the drying process and the eugenol content decreased. And the third problem is the oven that has been used so far is still fuel-wasting. The literature studies also found several parameters to be a reference in designing a new oven: the number of trays in the oven, clove thickness, the space between the trays in the oven, and the steam gap on the tray. In addition, the appropriate oven coating material can also be determined (plywood, galvanized plate, and air). In the TRIZ method, several solutions were found to design a new oven. Eight things have been changed from the existing drying oven, including the number of trays in the oven, a steam gap in each tray, the size of the mesh used for the tray base, material for the drying oven, the thickness of the cloves on the tray, the temperature used in the drying process, installation of a thermostat to control the temperature in the oven, separate combustion chamber from the tray space (indirect heating), and without using a blower

Physico-chemical characterization of ultrasound assisted clove oil-loaded nanoemulsion: As enhanced antimicrobial potential

Clove oil has a high eugenol content, making it an effective antimicrobial essential oil; nevertheless, its low water solubility, high volatility, and organoleptic qualities limit its use in food systems. As a result, we created an antibacterial system using clove oil-in-water nanoemulsion. Clove oil nanoemulsions were produced using whey protein concentrate (0.1–1%) as an emulsifier by ultrasonication and various physico-chemical characteristics (stability, particle size, zeta-potential, and poly dispersity index) were investigated. Mean particle size, zeta potential and polydispersity index of the most stable nanoemulsion were 279.0 ± 8.43 nm, -34.5 ± 0.12 mV, and 0.179 ± 0.012, respectively. Most stable nanoemulsion was fairly stable at different processing parameters such as various pH (3.0 – 7.0), temperature ranges (63 – 121 °C), and ionic strengths (0.1 – 1.0 M NaCl). Finally, antimicrobial activities, such as minimum inhibitory concentration was found with 50 µL, whereas minimum bactericidal concentration was observed to be 90 µL after 8 h contact time, against E. coli and B. subtilis strains.

Anti‐Inflammatory and Antimicrobial Activities of Fermented Ocimum sanctum Linn. Extracts against Skin and Scalp Microorganisms

This study aimed to revealed anti-inflammatory and antimicrobial activities of fermented Ocimum sanctum Linn. (FE). The fermentation process with Lactobacillus plantarum was compared with the solvent extraction methods. Antimicrobial activity against the growth of Staphylococcus aureus, Staphylococcus epidermidis, Propionibacterium acnes, Candida albicans, and Malassezia furfur was investigated via broth dilution method. High performance thin layer chromatography was used to determine eugenol content. The anti-inflammation was investigated by means of nuclear factor kappa B (NF-κB) expression inhibition by Western blot analysis. FE yielded the highest amount (11.93 % w/w), the highest eugenol content (39.3±12.6 % w/w), and the highest antimicrobial activities comparing to the extracts obtained from the solvent extractions. The fungal inhibition against M. furfur 656 was equivalent to that of ketoconazole. Furthermore, the bacterial inhibition on S. aureus and S. epidermidis was compared to that of Penicillin G at minimum inhibitory concentration (MIC) of 0.125 mg/mL and 0.25 mg/mL, respectively. Interestingly, FE had lower MIC and minimum bactericidal concentration against P. acnes than Penicillin G and also possessed comparable anti-inflammatory activity to indomethacin with the NF-κB suppression of 42.7±4.6 %. Therefore, FE are potentially natural anti-inflammation and antimicrobial agents for topical applications in the pharmaceutical and cosmetic industries.

The Essential Oils-bearing Plant Containing Eugenol in Vietnam

Aim and Objectives: Eugenol is widely used in the pharmaceutical and aromatic industries, so the task of surveying to find essential oils containing eugenol is very important. The purpose of this study is to investigate essential oil-bearing plants containing eugenol in Vietnam for pharmaceutical and aromatic industries.
 Materials and Methods: By the method of fresh sampling of essential oil plants, essential oils are extracted by steam distillation and then analyzed by high-resolution gas chromatography (HRGC) to identify eugenol sources.
 Results: We have found that a lot of plants containing high eugenol content mostly grow wild in forests such as Hiptis suaveolens Poit. containing 62-67% eugenol, Cinnamomum verum Prest: 75-80%, Camellia sasanqua Thumb.: 90-95% can be used to exploit essential oils and extract eugenol. We also pointed out that essential oil plants containing high eugenol as Cestrum nocturnum L.: 50-55%, Ocimum sanctum L.: 60-65%, Ocimum gratissimum L.: 65-75% can be cultivated to obtain eugenol for the pharmaceutical and aromatic industry.
 Conclusions: During the survey, we discovered and made a list of 10 plants as a source of essential oils containing eugenol in Vietnam. The rainy season in Vietnam is from June to September. During this season, the essential oil content in the fresh leaves is lower than in the dry season, therefore, the eugenol content in the essential oils is low. However, due to the strong-growth of plants in the rainy season, a lot of fresh leaves can be harvested, which mean there are more essential oils presented to be extracted.

Chemical composition and biological activities of two chemotype-oils from Cinnamomum verum J. Presl growing in North Brazil.

Chemical composition and antioxidant and antifungal action of the oils from leaves and wood bark of two chemotypes of Cinnamomum verum J. Presl were evaluated. Plants were sampled in the cities of São Luís and Santa Inês, state of Maranhão, Brazil. GC-MS and GC-FID, DPPH radical scavenging, and in vitro test against the phytopathogenic fungus Colletotrichum musae were used to perform these analyses. Cinnamomum verum is worldwide known as Cinnamon, highlighted for its extensive use in the cooking of diverse cultures of the world, and as a medicinal plant to treat environmental viral diseases. In the leaf oil of São Luís chemotype, eugenol (93.6%) was the main constituent, while in Santa Inês chemotype, it was benzyl benzoate (95.3%). In the bark wood oil of São Luís chemotype, (E)-cinnamaldehyde (89.3%) was the main constituent, while in Santa Inês chemotype, they were benzyl benzoate (23.3%), linalool (14.0%), (E)-caryophyllene (9.1%), caryolan-8-ol (7.2%) and borneol (4.7%). Leaf oils from both chemotypes showed strong to moderate antifungal activity, reaching 100% efficacy in eugenol-containing oils and above 70% in benzyl benzoate oils. In the antioxidant evaluation, the chemotype with a high eugenol content presented an inhibitory concentration higher than 80%, compared to Trolox. The leaf oils of the two C. verum chemotypes showed significant antifungal and antioxidant potential, considering their economic use as a functional and nutraceutical food supplement.

Biological properties of a biomaterial obtained from Syzygium aromaticum

Studies performed on Essential oil of Syzygium aromaticum (EOSa) from the Romanian market indicate a relative content of 73.18% in Eugenol. Due to this compound, the antioxidant activity determined with chemiluminescence technique, using luminol as a witness, give an average value of 98%. Studies performed on cell line THP-1, reveal that if this cell line is treated with EOSa, after 24 h of exposure at a concentration of minimum 0.05 μL/mL EOSa, then 27% of tumor cells are found in the apoptosis stage. Increasing EOSa concentration in the culture media of THP-1 cells up to 10 μL/mL does not affect the level of apoptotic cells. This value remains constant for the concentrations of EOSa situated in the range of (0.05 ÷ 10)μL/mL. The flowcitometry studies show that, if the concentration of EOSa increase up to 10 μL/mL, then 16% of THP-1 are found in the stage of necrosis. The biological tests performed in vitro reveal a high antioxidant activity of Syzygium aromaticum oils and a possible antitumor effect induced by apoptosis, due to the high content of Eugenol from bioproduct.

New technology in basil production with high essential oil yield and quality

Light modification by colour shade net manipulation plays an important role in the synthesis of bioactive compounds and has been shown to affect quantity and quality of essential oils in basil. In the present study, basil was grown in the soil under net-house cover by pearl and red nets (50% shade index), or in unshaded condition (open field-control). Sweet basil (Ocumum basilicum L. cv. ‘Genovese’) were used to determine whether different times of harvest could improve yield, chemical composition of essential oils and antioxidant activity under light stress conditions. The lowest accumulation of essential oils was observed in the second harvest from unshaded, control plants (1.02 mL/100 g) while the highest oil accumulation was achieved in first harvest from red nets (3.23 mL/100 g). The main constituents found in the oil were linalool (46.7–53.9%), eugenol (9.7–20.9%), 1,8-cineole (8.7–15.3%), epi-α-cadinol (3.3–4.5%) and α-trans-bergamotene (2.2–3.4%). Light manipulation by color shade nets also increased antioxidant activity. Plants grown under blue shade nets from the second harvest are characterized by the highest eugenol content (20.9%) and highest antioxidant activity (efficient concentration - EC50, 0.003 mg mL−1). Direct sowing, high plant density, colour shade nets and successive harvests represents a new technology in basil production with high essential oil yield and quality.

Effects of Carnation Essential Oil Extracted from Carnation Calli on Extending Shelf Life of Yoghurt

Carnation’s essential oil with high content of eugenol (monoterpenes) was extracted from carnation plant calli. Eugenol had antimicrobial effect and could be used to prolong the shelf life of fermented products as yoghurt. Eugenol in carnation essential oil was added to milk, at the percentages of (0.2, 0.4, 0.6, and 0.8 μl/ml milk, respectively before using the milk in the yoghurt manufacture. Results indicated that eugenol in carnation essential oil possessed good inhibitory effect against selected pathogenic bacterial strains at different concentrations, but had no inhibitory effect on Saccharomyces cerevisiae. Addition of carnation essential oil affected the pH and titratable acidity of the prepared yoghurt. Moreover, total solids, total protein and fat-to-dry matter records were slightly affected. The total viable counts, also, counts of yoghurt starter cultures and Lactobacillus acidophilus in yoghurt samples enhanced to become a maximum after 10 days of storage and reduced thereafter. Yeasts and molds, and coliform bacteria were not detected in the treated yoghurt. In different samples of yoghurt, yoghurt containing 0.6 μl/ml eugenol was the most acceptable organoleptically. It can be concluded that 0.6 μl/ml eugenol, can be applied to prolong yoghurt storage time for more than 15 days.
 Plant Tissue Cult. & Biotech. 29(1): 1-14, 2019 (June)

<i> Syzygium aromaticum</i> L. (Clove) Essential Oil as a Reducing Agent for the Green Synthesis of Silver Nanoparticles

The present investigation details a green synthesis of silver nanoparticles (AgNP) using the essential oil of Syzygium aromaticum L. (clove) as reducing agent, which is a matrix with a high content of eugenol, an important compound for the reducing action of silver nitrate. The synthesis of AgNP was performed at different pH conditions (pH 7, 8, 9 and 10), and was monitored by UV-Vis Spectroscopy, Dynamic Light Scattering (DLS) and Transmission Electron Microscopy. The synthesized nanoparticles presented characteristic Surface Plasmon Resonance bands with maximum absorbance between 405 and 460 nm. The DLS analysis revealed particle sizes from 31 to 72 nm and zeta potential between -30.1 and -50.8 mV indicating good stability against the agglomeration of the particles in solution. The micrographs obtained by TEM showed different particle shapes and a predominance of spherical-shaped nanoparticles, and average size ranging from 27 to 94 nm. The clove-based silver nanoparticles were efficient in controlling the growth of Escherichia coli and Staphylococcus aureus bacteria, and the minimum inhibitory concentration ranged from 60 to 100 μL/mL. This study highlights the feasibility of clove essential oil as an alternative for the synthesis of silver nanoparticles by a simple, inexpensive and eco-friendly method.

Evaluation of the effects of temperature and pressure on the extraction of eugenol from clove (Syzygium aromaticum) leaves using supercritical CO2

In this study, the effect of operational conditions on the extraction of clove leaves using CO2 on eugenol yield and content was investigated. The conditions used in the supercritical extraction with CO2 included temperatures of 40, 50, and 60 °C and pressures of 150, 185 and 220 bar. The highest yield (1.08 wt%) and highest eugenol content were obtained at 40 °C and 220 bar. The main components identified in the clove extract were eugenol (29.73%), chavicol (13.31%), n-pentacosane (11.66%), hexacosanal (11.37%), and vitamin E (9.30%). The extracts were evaluated for their antioxidant capacities by the DPPH and FRAP methods, and quantification of the phenolic compounds was done by the Folin-Ciocalteu method. The best results among the conditions were obtained at the lowest pressure and temperature, 150 bar and 40 °C. The Sovová model satisfactorily described the extraction kinetics in all the studied conditions.

In vitro evaluation of the amoebicidal activity of rosemary (Rosmarinus officinalis L.) and cloves (Syzygium aromaticum L. Merr. & Perry) essential oils against Acanthamoeba polyphaga trophozoites

Several species of the genus Acanthamoeba cause human diseases. Treatment of infections involves various problems, emphasising the need to develop alternative antiprotozoal agents. We studied the anti-amoebic activity of Essential Oils (EOs), derived from rosemary (Rosmarinus officinalis L.) and cloves (Syzygium aromaticum L. Merr. & Perry), against Acanthamoeba polyphaga strain. The amoebicidal activity of cloves and rosemary EOs was preliminary demonstrated by the morphology change (modifications in the cell shape, the presence of precipitates in the cytoplasm, autophagic vesicles, membrane blends) of the treated trophozoites. The cell-counts, carried out after staining trophozoites with a Trypan blue solution, revealed that both EOs were active in a dose-dependent manner and in relation to the exposure time. This activity was evident after few hours, with encouraging results obtained in particular with cloves EO, able to act at the lower concentrations and after 1 h, probably for its high eugenol content (65.30%).

Chemical characterization of aroma compounds in essential oil isolated from “Holy Basil” (Ocimum tenuiflorum L.) grown in India

Ocimum tenuiflorum L. (“Holy Basil”/“Tulsi”) is an indigenous Ayurvedic medicinal plant of India, widely distributed in tropical and warm temperate regions. Plant is well known for its enormous therapeutic activities and prevention against diseases. In the present study, thirty-two accessions of O. tenuiflorum germplasm collected from different regions of Northern India were evaluated for their essential oil content and composition. Essential oil obtained by hydrodistillation was analyzed by GC and GC/MS for aroma compounds. Essential oil content in O. tenuiflorum germplasm showed wide range of variation from 0.13 to 0.45 % on FWB. GC and GC/MS profile of O. tenuiflorum oil showed phenylpropanoids, mainly eugenol constituted the major proportion of essential oil. The range of major chemical constituents identified were eugenol (1.94–60.20 %), methyl eugenol (0.87–82.98 %), β-caryophyllene (4.13–44.60 %), β-elemene (0.76–32.41 %). Eugenol and methyl eugenol rich two chemotypes were identified in O. tenuiflorum germplasm. The accessions, IC583281, IC583285 and IC583322 were found to contain high eugenol content (>55 %), while three accessions IC583279, IC583284 and IC583278 were found to possess high methyl eugenol content (>70 %). Eugenol has been reported to be largely responsible for the therapeutic potentials of tulsi, while methyl eugenol is a high value aroma chemical used as flavouring agent. The results suggest holy basil have a potential as a new essential oil crops and can provide oil yields and composition typical for the respective species.