Composition Comparison of Essential Oils Extracted by Hydrodistillation and Microwave-assisted Hydrodistillation from Black Pepper (Piper nigrum L.) Grown in China

The components of essential oils extracted from Petroselinum crispum seeds were determined by the traditional technique hydrodistillation (HD) and microwave-assisted hydrodistillation (MHD). The optimum conditions of MHD were microwave radiation time 4 min at 600 w, microwave extraction time 40 min at 200 w, and a 1:30 material-water ratio. The yields of HD and MHD essential oils from parsley seeds were 3.44% and 4.45% (v/w), respectively. Thirty-one components were identified in the HD oil, comprising 98.95% of total oil. While thirty-five components were identified in the MHD oil, which accounted for 99.52% of all oil. Myristicin was the main component in both oils. The analysis of the extracts was performed by GC-MS.

Traditional hydrodistillation (HD) and microwave-assisted hydrodistillation (MHD) were compared and evaluated for their efficiency in the extract of Amomum tsao-ko essential oil. The optimum conditions for MHD were: microwave delivered power 800 W, microwave radiation time 5 min. and a 1:20 ratio of spice to water. The obtained oils were analyzed by GC and GC-MS. Thirty-two components were identified in HD oil and thirty-three components in MHD oil. Among the identified volatile compounds from A. tsao-ko, the main components from both oils were found to be similar, but their contents were significantly different including eucalyptol (33.81 % in HD oil, 38.39 % in MHD oil), 2-iso-propylbenzaldehyde (10.21 %, 9.98 %), nerol (8.54 %, 6.80 %), 3-heptylacrolein (5.10 %, 4.32 %).

Complex coacervates of β-lactoglobulin/sodium alginate for the microencapsulation of black pepper (Piper nigrum L.) essential oil: Simulated gastrointestinal conditions and modeling release kinetics

Encapsulation of black pepper (Piper nigrum L.) essential oil with gelatin and sodium alginate by complex coacervation

Very few studies have investigated the biological activities of black pepper essential oil (BPEO) in human cells. Therefore, in the current study, we examined the biological activities of BPEO in cytokine-stimulated human dermal fibroblasts by analyzing the levels of 17 important protein biomarkers pertinent to inflammation and tissue remodeling. BPEO exhibited significant antiproliferative activity in these skin cells and significantly inhibited the production of Collagen I, Collagen III, and plasminogen activator inhibitor 1. In addition, we studied the effect of BPEO on the regulation of genome-wide expression and found that BPEO diversely modulated global gene expression. Further analysis showed that BPEO affected many important genes and signaling pathways closely related to metabolism, inflammation, tissue remodeling, and cancer signaling. This study is the first to provide evidence of the biological activities of BPEO in human dermal fibroblasts. The data suggest that BPEO possesses promising potential to modulate the biological processes of tissue remodeling, wound healing, and metabolism. Although further research is required, BPEO appears to be a good therapeutic candidate for a variety of health conditions including wound care and metabolic diseases. Research into the biological and pharmacological mechanisms of action of BPEO and its major active constituents is recommended.

This study was conducted to compare between chemical composition, antimicrobial and cytotoxic activities of black pepper (Piper nigrum L.) essential oil and oleoresin. The essential oil and oleoresin were obtained by hydrodistillation and maceration techniques, respectively. The main constituents were analyzed using gas chromatography and mass spectrometry. The ratio of monoterpene hydrocarbons to sesquiterpene hydrocarbons indicated the higher quality of the essential oil and the oleoresin. The essential oil and oleoresin were screened for their antimicrobial activity against four pathogenic bacteria and two fungi strains. The black pepper essential oil exhibited higher antimicrobial activity than the oleoresin. In vitro, cytotoxicity evaluation against five cell lines of human hepatocellular, cervical, breast, prostate and larynx carcinoma, showed a potent anti-proliferative activity of the oleoresin with the lowest IC50 value belonging to the larynx carcinoma cells. The present results suggested promising cytotoxic, antimicrobial properties of the black pepper essential oil and oleoresin.

As many spices essential oil, black pepper (Piper nigrum) oil, which produced by steam distillation has shown the antimicrobial activity in many researches. However, essential oil was often hydrophobic and dispersed incompletely in food matrix. In our work, an oil‐in‐water nanoemulsion of black pepper oil was prepared by high speed homogenization method. In order to well disperse essential oil in water, the surfactant polyoxyethylene sorbitan monooleate (Tween 80) was utilized with the surfactant:oil ratios from 1:3 to 2:1. The other component of the nanoemulsion was soya oil, the high chain triglycerides in soya oil prevented the Oswald ripening of essential oil droplets by increasing their hydrophobicity. After changing the component concentration, the nanoemulsion was the most stable with 20 % oil phase, 6:4 pepper oil ‐ soya oil ratio and 1:1 surfactant oil ratio. At 9,000 rpm and 30 minutes stirring, the average droplet size was 61.9 nm with 0.462 PdI (polydispersity index). After 30‐day storage, the particle size increased to 87 nm at ambient temperature and 130 nm at 5°C.

Black pepper (Piper nigrum L.) is a tropical crop with extensive medicinal potential in ethnomedicine and nutraceutical applications. The essential oil of black pepper finds wide applications in inhabitation of respiratory infections and soothing of muscular pains due to its warming and energizing property. The pungent bioactive piperine is responsible for this function, and therefore, efficient technology is required for an optimal extraction process of this compound. In the present article, we have developed a procedure for extracting black pepper essential oil from Vietnam, optimizing conditions that affect the extraction process. The effect of process parameters, namely material size, preservation method, the concentration of sodium chloride, the concentration of soak time, the ratio of material to water, temperature extraction, time extraction on the extraction yield, and relative efficiency were investigated. Results demonstrated that 20 g of black pepper milled with a mesh size of 160 obtained 0.48 g of essential oil (2.4%) at a raw material to water ratio of 1/21 (g/mL) at 150 °C in a time of 5.2 h. GC-MS (Gas chromatography–mass spectrometry) spectra showed that 3-carene (29.21%), D-limonene (20.94%), caryophyllene (15.05%), and β-pinene (9.77%) were present as major components. These results suggested that the essential oil extracted from Vietnamese black pepper is applicable in the manufacturing processes of insecticides and air deodorizers.

The active compounds isolated from Black pepper have anticancer effects, but the bioactivity of Black pepper essential oil (BP-EO) is rarely studied. BP-EO has poor stability and a suitable dose form should be prepared for in vivo delivery. Triple negative breast cancer (TNBC) has attracted more and more attention due to its high mitotic index, high metastasis rate and poor prognosis. In this study, the composition of BP-EO was analyzed by gas chromatography-mass spectrometry (GC-MS), and nanoparticles (NPs) loaded with BP-EO were prepared by nanoprecipitation method using Eudragit L100 as a carrier. We investigated the preparation, characterization, stability and in vitro release of nanoparticles. MTT assay, cell wound healing, Transwell invasion assay and Western blot were used to study the anti-tumor effect and mechanism of MDA-MB-231 cells. The GC-MS analysis identified a total of 33 compounds among which alkenes account for 63.55%. The prepared BP-EO NPs exhibited nanoscale morphology, good stability and pH-responsive and sustained release character which is suitable for in vivo delivery. BP-EO NPs significantly inhibited the proliferation, migration and invasion of MDA-MB-231 cells. Furthermore, BP-EO NPs significantly inhibited the expressions of Wnt and β-catenin and significantly activated the expression of GSK-3β in MDA-MB-231 cells. Therefore, BP-EO NPs prepared in this study provide a new effective strategy for the treatment of TNBC. PRACTICAL APPLICATIONS: Black pepper is rich in essential oil and has excellent antioxidant and antibacterial activities. However, the anti-tumor activity of BP-EO has not been studied. In this study, we found that BP-EO has excellent anticancer activity. To achieve effective encapsulation of black pepper essential oil and an excellent anti-triple negative breast cancer activity, nanoparticles loaded with BP-EO were prepared using Eudragit L100 as the carrier by the nanoprecipitation method. The in vitro study revealed that BP-EO NPs inhibited proliferation, migration and invasion of MDA-MB-231 cells via inhibiting the Wnt/β-Catenin signaling pathway. This study provides new ideas and innovations for the treatment of invasive triple negative breast cancer in the future. At the same time, we will further reveal the application potential, pharmacokinetic characteristics and precise mechanism of BP-EO NPs in vivo in subsequent studies.

The development of environmentally friendly methods for nanoparticle synthesis has gained increasing attention. Black pepper essential oil contains secondary metabolites that act as both reducing and stabilizing agents, making it a promising green alternative in silver nanoparticle (AgNP) synthesis. This study aims to investigate the effect of pH and synthesis time on the yield and characteristics of AgNP synthesized using black pepper essential oil via the sonochemical method. AgNP synthesis was carried out using the sonochemical method by adding black pepper essential oil to a silver nitrate solution. AgNP were synthesized at pH levels of 8, 9, and 10 with reaction times of 30, 60, and 90 minutes. The obtained AgNP were analyzed for yield, UV-Vis absorbance, and particle size distribution. The results demonstrated that yield increased with higher pH and longer synthesis time, reaching a maximum of 58.12% at pH 10 and 90 minutes. UV-Vis analysis confirmed the presence of AgNP with absorption peaks between 400–500 nm. The particle size ranged from 9.66 to 348 nm, indicating size variability influenced by synthesis conditions. These findings highlight the potential of black pepper essential oil as a green and sustainable approach for AgNP synthesis, offering eco-friendly benefits for various applications.

Black pepper (Piper nigrum L.) is a tropic plant with large applications due to its commercial, economic, nutritional, and medicinal value. Pepper essential oil is a valuable product from pepper with diverse applications. The extraction of essential oil from pepper is a potential option to enhance its economic value. For this study, the pilot scale hydrodistillation process was employed to extract essential oil from two types of pepper from Vietnam, including whole black pepper (570 g/l) and light berries black pepper (300 g/l). Extraction parameters such as time, temperature, rate, and the material to water ratio were optimized. The quantitative analyses of the essential oils were performed by Gas Chromatography-Mass Spectrometry. The optimum yield was achieved up to 2.38% for light berries black pepper when the extract conditions were set up at a material-water ratio of 1:12.5 (kg/l) for 180 minutes under the extraction temperature of 130 °C. For whole black pepper (570 g/l), the maximum yield was 1.65% at distillation conditions: material-water ratio of 1:15 (kg/l), distillation time of 210 minutes, and temperature of 140 °C. The analysis of essential oils quality showed that all the sensory criteria, physical properties, and chemical composition of the two types of black pepper essential oils satisfied the regulation of ISO 3061: 2008 and TCVN 11881: 2017 black pepper essential oil. B-caryophyllene (28.28%; 21.94%), 3-carene (23.27%; 26%), and D-limonene (14,74%; 20.96%) were the three main components with the highest content in both types of black pepper essential oil compositions.

In this study, black pepper essential oil nanoemulsions formulated using low-energy methods (emulsion phase inversion and phase inversion temperature) were compared. In both the methods, optimum components' concentration was 10% of essential oil, 20% of Tween 80, and 70% of distilled water. All nanoemulsions were unchanged after centrifuging at 825 or 1,467 g for 10 min and were more stable when kept at 30°C. Phase inversion temperature nanoemulsions quickly increased droplet size and polydispersity index after 2 weeks, then separated, and created creaming layer on the top after 4 weeks while emulsion phase inversion nanoemulsions were still homogeneous for 4 weeks. However, phase inversion temperature nanoemulsions were more stable than emulsion phase inversion nanoemulsions during heating–cooling cycles. In addition, the loading efficiency of emulsion phase inversion samples was also higher than phase inversion temperature samples, 92.13% and 81.52%, respectively. Practical applications Black pepper essential oil such as other plant essential oils has proved their bioactivity of antimicrobial, antioxidant. Therefore, utilization of essential oil in food industry has set a new trend as a natural food additive. However, essential oils are not easy to add into food products due to the presence of hydrophobic and volatile components. Nanoemulsion is expected to be one of suitable systems for dispersing essential oil in food environment. Essential oil nanoemulsion made from black pepper, very popular spice all over the world, has potential for using as a food preservative for not only many food techniques, but also many kinds of food: dripping fresh food material, spraying on food material, using as seasoning for canning food, or other processing food. Novelty impact statement In this study, Vietnamese black pepper (Piper nigrum) essential oil nanoemulsions were successfully formulated using the phase inversion temperature (PIT) method. Both the emulsion phase inversion (EPI) and PIT methods formed small droplet of 32.4 and 82.4 nm, respectively. However, EPI nanoemulsions were not only more homogeneous, but also more steady than PIT nanoemulsions in our experiment condition.

The microwave-assisted hydrodistillation (MHD) and traditional hydrodistillation (HD) were compared and evaluated for their efficiency in the isolation of Kaempferia galanga L. essential oil. The optimum conditions for MHD were: microwave delivered power 1000 W, microwave radiation time 3 min. and a 1:25 ratio of material to water. The obtained oils were analyzed by GC and GC-MS. Forty-two components were identified in MHD oil and forty-five components in HD oil. Among the identified volatile compounds from K. galanga, the main components from both oils were found to be similar, but their contents were significantly different including iso-amyl p-methoxycinnamate (42.8 %, 27.5 %), n-pentadecane (21.6 %, 32.8 %), ethyl cinnamate (16.1 %, 17.1 %), cyperene (2.0 %, 3.4 %) and p-methoxystyrene (1.6 %, 2.6 %) in MHD oil and HD oil, respectively.

The composition of essential oils extracted from Amomum kravanh and Amomum compactum was determined by traditional hydrodistillation (HD) and microwave-assisted hydrodistillation (MHD). The optimum conditions for MHD were: microwave delivered power 800 W, microwave radiation time 5 min and a 1:25 ratio of material to water. Thirty components were identified in the HD oil and twenty-eight components in the MHD oil of A. kravanh, whereas twenty-seven components were identified in the HD oil and twenty-six components in the MHD oil of A. compactum, which accounts for over 95 % of all the volatile oils. The analysis of the extracts was performed by GC and GC-MS.

Black pepper (Piper nigrum) is historically one of the most important spices and herbal medicines, and is now cultivated in tropical regions worldwide. The essential oil of black pepper fruits has shown a myriad of biological activities and is a commercially important commodity. In this work, five black pepper essential oils from eastern coastal region of Madagascar and six black pepper essential oils from the Amazon region of Brazil were obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The major components of the essential oils were α-pinene, sabinene, β-pinene, δ-3-carene, limonene, and β-caryophyllene. A comparison of the Madagascar and Brazilian essential oils with black pepper essential oils from various geographical regions reported in the literature was carried out. A hierarchical cluster analysis using the data obtained in this study and those reported in the literature revealed four clearly defined clusters based on the relative concentrations of the major components.