Evaluating the antimicrobial potential of green cardamom essential oil focusing on quorum sensing inhibition of Chromobacterium violaceum

Cardamom seed bioactives: A review of agronomic factors, preparation, extraction and formulation methods based on emerging technologies to maximize spice aroma economic value and applications

Cardamom seed (Elettaria cardamomum (L.)) is a well-appreciated spice in food and pharmaceutical industries owing to its unique rich flavor dominated by oxygenated monoterpenoids, α-terpinyl acetate and 1,8-cineole, to which most of the quality of cardamom essential oil (CEO) is attributed. CEO output is greatly influenced by different agronomic factors, processing, and EO extraction methods. In that context, the goal of this study is to provide an overarching review regarding emerged technologies along with their optimization parameters to achieve optimal oil yield with the best flavor quality. Furthermore, the recent approaches employed in CEO stabilization were highlighted alongside their pharmaceutical and food applications. Moreover, the different aspects of superlative CEO production including agricultural aspects, climatic requirements, and processing methods were also explained.

Exploring the therapeutic potential of medicinal plants and their active principles in dental care: A comprehensive review

Since the human population realized how important it was to maintain overall health and the weight of disease, they have been looking for therapeutic qualities in natural environments. The use of plants having medicinal qualities for the treatment and prevention of illnesses that may have an impact on general health is known as herbal medicine. There has been a noticeable increase in interest lately in the combination of synthetic contemporary medications and traditional herbal remedies. About 80 % of people rely on it for healthcare, particularly in developing nations. One important aspect of overall health is said to be oral healthcare. The World Health Organization views oral health as a crucial component of overall health and well-being. Because they are more readily available, less expensive, and have fewer adverse effects than pharmaceutical treatments, using natural medicines to treat pathologic oro-dental disorders can make sense. The current evaluation of the literature sought to investigate the range and scope of the use of herbal products and their secondary metabolites in maintaining oral health, encompassing several oral healthcare domains such as halitosis, gingivitis, periodontitis, and other oral disorders. Therefore, there are many herbs discussed in this work and their mechanism in the treatment and improvement of many oral ailments. Besides, compounds that are useful in oral treatment with their natural sources and the cases where they can be used. To prevent any possible side effects or drug interactions, a doctor's consultation is necessary before using dental medicine. Although herbal therapy is safe and with minimum side effects, it is also strongly advised to do a more thorough preclinical and clinical evaluation before using herbal medicines officially.

Deciphering the Potentials of Cardamom in Cancer Prevention and Therapy: From Kitchen to Clinic

Cardamom (cardamum) is a spice produced from the seeds of several Elettaria and Amomum plants of the Zingiberaceae family. Cardamom has been demonstrated to offer numerous benefits, including its antioxidant, antimicrobial, anti-inflammatory, and other metabolic (anti-diabetic) properties, and its potential to reduce cancer risk. Recently, researchers have extracted and tested multiple phytochemicals from cardamom to assess their potential effectiveness against various types of human malignancy. These studies have indicated that cardamom can help overcome drug resistance to standard chemotherapy and protect against chemotherapy-induced toxicity due to its scavenging properties. Furthermore, chemical compounds in cardamom, including limonene, cymene, pinene, linalool, borneol, cardamonin, indole-3-carbinol, and diindolylmethane, primarily target the programmed cell death lignin-1 gene, which is more prevalent in cancer cells than in healthy cells. This review provides the medicinal properties and pharmacological uses of cardamom, its cellular effects, and potential therapeutic uses in cancer prevention and treatment, as well as its use in reducing drug resistance and improving the overall health of cancer patients. Based on previous preclinical studies, cardamom shows significant potential as an anti-cancer agent, but further exploration for clinical use is warranted due to its diverse mechanisms of action.

Chemical Compositions and Fumigation Effects of Essential Oils Derived from Cardamom, Elettaria cardamomum (L.) Maton, and Galangal, Alpinia galanga (L.) Willd, against Red Flour Beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae)

This study explores the use of essential oils from cardamom (Elettaria cardamomum (L.) Maton) and galangal (Alpinia galanga (L.) Willd) as alternatives to synthetic insecticides for controlling the red flour beetle, Tribolium castaneum (Herbst). The chemical compositions of these oils were analyzed using GC-MS, and their fumigation effects were tested in a vapor-phase bioassay. The experiment followed a factorial design with four types of essential oils, namely, those manually extracted from cardamom leaves (MCL) and galangal leaves (MGL) and those commercially produced from cardamom seeds (CCS) and galangal rhizomes (CGR), at seven concentrations (0, 50, 100, 150, 200, 250, and 300 µL/L air). The manually extracted oils yielded 0.6% from cardamom leaves and 0.25% from galangal leaves. MCL contained 28 components, with eucalyptol (25.2%) being the most abundant, while CCS had 34 components, primarily α-terpinyl acetate (46.1%) and eucalyptol (31.2%). MGL included 25 components, mainly caryophyllene (28.7%) and aciphyllene (18.3%), whereas CGR comprised 27 components, with methyl cis-cinnamate (47.3%) and safrole (19.8%) as the major constituents. The fumigation bioassay results revealed that CGR was the most effective, demonstrating the highest mortality rates of T. castaneum across all the tested periods and concentrations, achieving up to 96% mortality at 168 h with a concentration of 300 µL/L air. Statistical analyses showed significant differences in mortality based on the type and concentration of essential oil, particularly after 96 h. These findings highlight the potential of CGR, with its advantages and differences in chemical composition, as an effective biopesticide against T. castaneum, with increasing efficacy over time and at higher concentrations.

A hybrid structure based on silk fibroin/PVA nanofibers and alginate/gum tragacanth hydrogel embedded with cardamom extract

Hybrid structures made of natural-synthetic polymers have been interested due to high biological features combining promising physical-mechanical properties. In this research, a hybrid dressing consisting of a silk fibroin (SF)/polyvinyl alcohol (PVA) nanofibers and sodium alginate (SA)/gum tragacanth (GT) hydrogel incorporating cardamom extract as an antibacterial agent was prepared. Accordingly, SF was extracted from cocoons followed by electrospinning in blend form with PVA (SF/PVA ratio: 1:1) under the voltage of 18 kV and the distances of 15 cm. The SEM images confirmed the formation of uniform, bead free fibers with the average diameter of 199 ± 28 nm. FTIR and XRD results revealed the successful extraction of SF and preparation of mixed fibrous mats. Next, cardamom oil extract-loaded SA/GT hydrogel was prepared and the nanofibrous structure was placed on the surface of hydrogel. SEM analysis depicted the uniform morphology of hybrid structure with desirable matching between two layers. TGA analysis showed desired thermal stability. The swelling ratio was found to be 1251% after 24 h for the hybrid structure and the drug was released without any initial burst. MTT assay and cell attachment results showed favorable biocompatibility and cell proliferation on samples containing extract, and antibacterial activity values of 85.35% against S. aureus and 75% against E. coli were obtained as well. The results showed that the engineered hybrid nanofibrous-hydrogel film structure incorporating cardamom oil extract could be a promising candidate for wound healing applications and skin tissue engineering.

In Vitro Evaluation of Synergistic Essential Oils Combination for Enhanced Antifungal Activity against Candida spp

In recent years, a significant number of infections have been attributed to non-albicidal Candida species (NAC), mainly due to the increasing resistance of NAC to antifungal agents. As only a few antifungal agents are available (azoles, echinocandins, polyenes, allylamines and nucleoside analogues), it is very important to look for possible alternatives to inhibit resistant fungi. One possibility could be essential oils (EOs), which have been shown to have significant antifungal and antibacterial activity. Therefore, in this study, the efficacy of 12 EOs and their combinations was evaluated against four yeasts of the genus Candida (C. albicas, C. glabrata, C. tropicalis and C. parapsilosis). GC-MS and GC-MS FID techniques were used for the chemical analysis of all EOs. VITEK-2XL was used to determine the antifungal susceptibility of the tested Candida spp. strains. The agar disc diffusion method was used for primary screening of the efficacy of the tested EOs. The broth dilution method was used to determine the minimum inhibitory concentrations (MICs) of the most potent EOs. After MIC cultivation, the minimum fungicidal concentration (MFC) was determined on Petri dishes (60 mm). The synergistic effect of combined EOs was evaluated using the checkerboard method and expressed as a fractional inhibitory concentration index (FICI). The results showed that ginger > ho-sho > absinth > dill > fennel > star anise > and cardamom were the most effective EOs. For all Candida species tested, the synergy was mainly observed in these combinations: ginger/fennel for C. albicans FICI 0.25 and C. glabrata, C. tropicalis and C. parapsilosis FICI 0.5 and absinth/fennel for C. albicans FICI 0.3125, C. tropicalis FICI 0.3125 and C. parapsilosis FICI 0.375. Our results suggest that the resistance of fungal pathogens to available antifungals could be reduced by combining appropriate EOs.

Health-promoting compounds in Amomum villosum Lour and Amomum tsao-ko: Fruit essential oil exhibiting great potential for human health

The Zingiberaceae family serves as a diverse repository of bioactive phytochemicals, comprising approximately 52 genera and 1300 species of aromatic perennial herbs distinguished by their distinct creeping horizontal or tuberous rhizomes. Amomum villosum Lour. and Amomum tsao-ko Crevost & Lemaire., are the important plants of family Zingiberaceae that have been widely used in traditional medicine for the treatment of many ailments. The Amomum species are employed for their aromatic qualities and are valued as spices and flavorings. In the essential oils (EOs) of Amomum species, notable constituents include, camphor, methyl chavicol, bornyl acetate, trans-p-(1-butenyl) anisole, α-pinene, and β-pinene.

OBJECTIVE

The aim of this review is to present an overview of pharmacological studies pertaining to the extracts and secondary metabolites isolated from both species. The foremost objective of review is not only to increase the popularity of Amomum as a healthy food choice but also to enhance its status as a staple ingredient for the foreseeable future.

RESULT

We endeavored to gather the latest information on antioxidant, antidiabetic, anticancer, antiobesity, antimicrobial, and anti-inflammatory properties of plants as well as their role in neuroprotective diseases. Research conducted through in-vitro studies, animal model, and compounds analysis have revealed that both plants exhibit a diverse array health promoting properties.

CONCLUSION

the comprehensive review paper provides valuable insights into the diverse range of bioactive phytochemicals found in A. villosum and A. tsao-ko, showcasing their potential in preventing diseases and promoting overall human well-being. The compilation of information on their various health-enhancing properties contributes to the broader understanding of these plants and their potential applications in traditional medicine and beyond.

Emerging trends in the inhibition of bacterial molecular communication: An overview

Quorum sensing (QS) is a molecular cell-cell communication utilized by several bacteria and some fungi. It involves cell density dependent gene expression that includes extra polymeric substance production, sporulation, antibiotic production, motility, competence, symbiosis and conjugation. These expressions were carried out by different signaling molecules like acyl homo-serine lactone (AHL) and auto-inducing peptides (AIPs) which was effluxed by gram negative and gram positive bacteria. Pathogenic bacteria and biofilms often exhibit high resistance to antibiotics, attributed to the presence of antibiotic efflux pumps, reduced membrane permeability, and enzymes that deactivate quorum sensing (QS) inhibitors. To counteract virulence and multi-drug resistance (MDR), novel strategies such as employing quorum sensing (QS) inhibitors and quorum quenchers are employed. It targets signaling molecules with synthesis and prevents the signal from binding to receptors. In this present review, the mechanisms of QS along with inhibitors from different sources are described. These strategies potentially interfere with QS and it can be applied in different fields, mainly in hospitals and marine environments where the pathogenic infections and biofilm formation are highly involved.

Extraction of Active Compounds from Mixtures of Hemp (Cannabis sativa) with Plants of the Zingiberaceae Family

Hemp is probably one of the most studied plants for its health-promoting properties, with countless documented and patented extraction methods, but literature is scarce on the simultaneous extraction of mixture of raw materials. Hemp, along with other plant materials, could represent a potentially highly valuable source material with resulting reciprocal effects. In this study, hemp (Cannabis sativa) and three members of the Zingiberaceae family, ginger (Zingiber officinale), turmeric (Curcuma longa), and cardamom (Elettaria cardamomum), were extracted simultaneously, and their bioactive component values were investigated. Two extraction methods were used, namely ultrasound-assisted extraction with ethanol and supercritical fluid extraction with carbon dioxide. First, extracts were obtained from separate plant materials. Then, hemp was extracted in combination with ginger, turmeric, and cardamom in a 1:1 ratio. The extracts obtained were evaluated for their antioxidant activity and total phenolic content using UV/VIS spectrophotometry; cannabinoid content, 6-gingerol, and 6-shogaol were measured using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS); volatile components such as 1,8-cineole, alpha-terpinyl acetate, linalool, and aR-turmerone were measured using gas chromatography with mass spectrometry (GC/MS).

Comparison of the Efficiency of Selected Disinfectants against Planktonic and Biofilm Populations of Escherichia coli and Staphylococcus aureus

The aim of this study is to compare the efficacy of selected food disinfectants on planktonic populations of Staphylococcus aureus and Escherichia coli and on the same microorganisms (MOs) incorporated in a biofilm. Two disinfectants were used for treatment: peracetic acid-based disinfectant (P) and benzalkonium chloride-based disinfectant (D). Testing of their efficacy on the selected MO populations was performed using a quantitative suspension test. The standard colony counting procedure was used to determine their efficacy on bacterial suspensions in tryptone soy agar (TSA). The germicidal effect (GE) of the disinfectants was determined based on the decimal reduction ratio. For both MOs, 100% GE was achieved at the lowest concentration (0.1%) and after the shortest exposure time (5 min). Biofilm production was confirmed with a crystal violet test on microtitre plates. Both E. coli and S. aureus showed strong biofilm production at 25 °C with E. coli showing significantly higher adherence capacity. Both disinfectants show a significantly weaker GE on 48 h biofilms compared to the GE observed after application of the same concentrations on planktonic cells of the same MOs. Complete destruction of the viable cells of the biofilms was observed after 5 min of exposure to the highest concentration tested (2%) for both disinfectants and MOs tested. The anti-quorum sensing activity (anti-QS) of disinfectants P and D was determined via a qualitative disc diffusion method applied to the biosensor bacterial strain Chromobacterium violaceum CV026. The results obtained indicate that the disinfectants studied have no anti-QS effect. The inhibition zones around the disc therefore only represent their antimicrobial effect.

Phytobioactive compounds as therapeutic agents for human diseases: A review

Phytobioactive compounds are plant secondary metabolites and bioactive compounds abundantly present in medicinal plants and have remarkable therapeutic potential. Oxidative stress and antibiotic resistance are major causes of present-day ailments such as diabetes, atherosclerosis, cardiovascular disorders, cancer, and inflammation. The data for this review were collected from Google Scholar, PubMed, Directory of Open Access Journals (DOAJ), and Science Direct by using keywords: "Medicinal plants, Phytobioactive compounds, Polyphenols, Alkaloids, Carotenoids etc." Several studies have reported the pharmacological and therapeutic potential of the phytobioactives. Polyphenols, alkaloids, terpenes, and polysaccharides isolated from medicinal plants showed remarkable antioxidant, anticancer, cytotoxic, anti-inflammatory, cardioprotective, hepatoprotective, immunomodulatory, neuroprotective, and antidiabetic activities. This literature review was planned to provide comprehensive insight into the biopharmacological and therapeutic potential of phytobioactive compounds. The techniques used for the extraction and isolation of phytobioactive compounds, and bioassays required for their biological activities such as antioxidant, antimicrobial, anti-inflammatory, and cytotoxic activities, have been discussed. Characterization techniques for the structural elucidation of phytobioactive compounds such as HPLC, TLC, FTIR, GC-MS/MS, and NMR have also been discussed. This review concludes that phytobioactive compounds may be used as potential alternative to synthetic compounds as therapeutic agents for the treatment of various diseases.

Metabolomic Analysis of the Effect of Lippia origanoides Essential Oil on the Inhibition of Quorum Sensing in Chromobacterium violaceum

Bacteria can communicate through quorum sensing, allowing them to develop different survival or virulence traits that lead to increased bacterial resistance against conventional antibiotic therapy. Here, fifteen essential oils (EOs) were investigated for their antimicrobial and anti-quorum-sensing activities using Chromobacterium violaceum CV026 as a model. All EOs were isolated from plant material via hydrodistillation and analyzed using GC/MS. In vitro antimicrobial activity was determined using the microdilution technique. Subinhibitory concentrations were used to determine anti-quorum-sensing activity by inhibition of violacein production. Finally, a possible mechanism of action for most bioactive EOs was determined using a metabolomic approach. Among the EOs evaluated, the EO from Lippia origanoides exhibited antimicrobial and anti-quorum activities at 0.37 and 0.15 mg/mL, respectively. Based on the experimental results, the antibiofilm activity of EO can be attributed to the blockage of tryptophan metabolism in the metabolic pathway of violacein synthesis. The metabolomic analyses made it possible to see effects mainly at the levels of tryptophan metabolism, nucleotide biosynthesis, arginine metabolism and vitamin biosynthesis. This allows us to highlight the EO of L. origanoides as a promising candidate for further studies in the design of antimicrobial compounds against bacterial resistance.

Current Understanding of the Molecular Basis of Spices for the Development of Potential Antimicrobial Medicine

Antimicrobial resistance increases day by day around the world. To overcome this situation new antimicrobial agents are needed. Spices such as clove, ginger, coriander, garlic, and turmeric have the potential to fight resistant microbes. Due to their therapeutic properties, medicinal herbs and spices have been utilized as herbal medicines since antiquity. They are important sources of organic antibacterial substances that are employed in treating infectious disorders caused by pathogens such as bacteria. The main focus of the study is the bioactivity of the active ingredients present in different kinds of naturally available spices. We conducted a thorough search of PubMed, Google Scholar, and Research Gate for this review. We have read many kinds of available literature, and in this paper, we conclude that many different kinds of naturally available spices perform some form of bioactivity. After reading several papers, we found that some spices have good antimicrobial and antifungal properties, which may help in controlling the emerging antimicrobial resistance and improving human health. Spices have many phytochemicals, which show good antimicrobial and antifungal effects. This review of the literature concludes that the natural bioactivate compounds present in spices can be used as a drug to overcome antimicrobial resistance in human beings.

GC, GC/MS Analysis, and Biological Effects of Essential Oils from Thymus mastchina and Elettaria cardamomum

Spanish marjoram (Thymus mastichina) and cardamom (Elettaria cardamomum) are traditional aromatic plants with which several pharmacological properties have been associated. In this study, the volatile composition, antioxidative and antimigratory effects on human breast cancer (MDA-MB-468 cell line), antimicrobial activity, and antibiofilm effect were evaluated. Results obtained via treatment of human breast cancer cells generally indicated an inhibitory effect of both essential oils (EOs) on cell viability (after long-term treatment) and antioxidative potential, as well as the reduction of nitric oxide levels. Antimigratory effects were revealed, suggesting that these EOs could possess significant antimetastatic properties and stop tumor progression and growth. The antimicrobial activities of both EOs were determined using the disc diffusion method and minimal inhibition concentration, while antibiofilm activity was evaluated by means of mass spectrometry. The best antimicrobial effects of T. mastichina EO were found against the yeast Candida glabrata and the G⁺ bacterium Listeria monocytogenes using the disc diffusion and minimal inhibitory concentration methods. E. cardamomum EO was found to be most effective against Pseudomas fluorescens biofilm using both methods. Similarly, better effects of this oil were observed on G^- compared to G⁺ bacterial strains. Our study confirms that T. mastichina and E. cardamomum EOs act to change the protein structure of older P. fluorescens biofilms. The results underline the potential use of these EOs in manufactured products, such as foodstuffs, cosmetics, and pharmaceuticals.

Antibiofilm and Quorum Sensing Inhibition (QSI) Potential of Lagerstroemia speciosa Leaves Extract

Disruption of quorum sensing pathway of pathogenic microbes is considered as novel approach to fight against infectious diseases. The current study was planned to evaluate the antibiofilm and quorum sensing inhibitory potential of Lagerstroemia speciosa. Antibacterial and antibiofilm potential of L. speciosa extracts was determined through agar well diffusion and crystal violet assay against sinusitis isolates, that is, Staphylococcus aureus, Enterococcus faecalis, Proteus mirabilis, and Klebsiella pneumoniae, while quorum sensing inhibition efficacy of L. speciosa extracts was determined through violacein inhibition assay using Chromobacterium pseudoviolaceum as bacterial model. The methanolic extract of L. speciosa presented the highest antimicrobial activity against E. faecalis and antibiofilm activity against K. pneumoniae (77.42 ± 1.51%), while n-hexane extract was found to be least active against all tested bacterial strains. Quorum sensing inhibition activity of L. speciosa extracts against C. pseudoviolaceum showed significant dose-dependent inhibition in violacein production by different concentrations of methanolic extract. Furthermore, none of the extracts of L. speciosa showed any hemolytic activity against human RBCs and hold considerable thrombolytic potential in comparison to streptokinase (75.9 ± .46%). In conclusion, findings suggest that L. speciosa leaves are excellent source of phytochemicals with potent antibiofilm and quorum sensing inhibition potential.

Recent advances in the extraction, chemical composition, therapeutic potential, and delivery of cardamom phytochemicals

Dietary phytochemicals including plant-derived alkaloids, carotenoids, organosulfur compounds, phenolics, and phytosterols, are health-promoting bioactive compounds that help in the prevention and mitigation of chronic diseases and microbial infections beyond basic nutrition supply. This article covers recent advances in the extraction, chemical composition, therapeutic potential (nutraceutical and antimicrobial), and delivery of black and green cardamom-derived phytochemicals. In recent years, advance extraction techniques (e.g., enzyme- assisted-, instant controlled pressure drop-, microwave- assisted-, pressurized liquid-, sub- critical-, supercritical fluid-, and ultrasound-assisted extractions) have been applied to obtain phytochemicals from cardamom. The bioactive constituents identification techniques, specifically GC-MS analysis revealed that 1,8-cineole and α-terpinyl acetate were the principle bioactive components in black and green cardamom. Regarding therapeutic potential, research findings have indicated desirable health properties of cardamom phytochemicals, including antioxidant-, anti-hypercholesterolemic, anti-platelet aggregation, anti-hypertensive, and gastro-protective effects. Moreover, antimicrobial investigations revealed that cardamom phytochemicals effectively inhibited growth of pathogenic microorganisms (bacteria and fungi), biofilm formation inhibition (Gram-negative and Gram-positive bacteria) and bacterial quorum sensing inhibition. Encapsulation and delivery vehicles, including microcapsules, nanoparticles, nanostructured lipid carriers, and nanoliposomes were effective strategies to enhance their stability, bioavailability and bioefficacy. In conclusion, cardamom phytochemicals had promising therapeutic potentials (antioxidant and antimicrobial) due to polyphenols, thus could be used as functional additive to increase shelf life, inhibit oxidative rancidity and confer pleasant aroma to commercial edibles as well as mitigate oxidative stress and lifestyle related chronic diseases (e.g., cardiovascular and gastrointestinal diseases). A future perspective concerning the fabrication of functional foods, nutraceuticals and antibiotics to promote cardamom phytochemicals applications as biotherapeutic agents at large-scale requires thorough investigations, e.g., optimum dose and physical form of supplementation to obtain maximum health benefits.

Recent advances in self-assembly behaviors of prolamins and their applications as functional delivery vehicles

Prolamins are a group of storage proteins (zeins, kafirins, hordeins, secalins, gliadins, glutenins, and avenins) found in the endosperm of cereal grains and characterized by high glutamine and proline content. With the high proportion of nonpolar amino acids (40-80%) and peculiar solubility (alcohol (60-90%), acetic acid, and alkaline solutions), prolamins exhibit tunable self-assembly behaviors. In recent years, research practices of utilizing prolamins as green building materials of functional delivery vehicles to improve the health benefits of bioactive compounds have surged due to their attractive advantages (e.g. sustainability, biocompatibility, fabrication potential, and cost-competitiveness). This article covers the recent advances in self-assembly behaviors leading to the fabrication of nanoparticles, fibers, and films in the bulk water phase, at the air-liquid interface, and under the electrostatic field. Different fabrication methods, including antisolvent precipitation, evaporation induced self-assembly, thermal treatment, pH-modulation, electrospinning, and solvent casting for assembling nanoarchitectures as functional delivery vehicles are highlighted. Emerging industrial applications by mapping patents, including encapsulation and delivery of bioactive compounds and probiotics, active packaging, Pickering emulsions, and as functional additives to develop safer, healthier, and sustainable food products are discussed. A future perspective concerning the fabrication of prolamins as advanced materials to promote their commercial food applications is proposed.

Biopolymer-based functional films for packaging applications: A review

Food packaging is a coordinated system comprising food processing, protection from contamination and adulteration, transportation and storage, and distribution and consumption at optimal cost with a minimum environmental impact to the packed food commodity. Active packaging involves deliberate addition of the functional ingredients either in the film or the package headspace to preserve the food quality, improve safety and nutrition aspects, and enhance the shelf-life. In this review, recent advances in the fabrication of biopolymer-based films, their classification (biodegradable-, active-, and intelligent packaging films), advanced fabrication strategies (composite-, multilayer-, and emulsified films), and special functions induced by the biopolymers to the film matrix (mechanical-, water resistance and gas barrier-, and optical properties, and bioactive compounds reservoir) were briefly discussed. A summary of conclusions and future perspectives of biopolymer-based packaging films as advanced biomaterial in preserving the food quality, improving safety and nutrition aspects, and enhancing shelf-life of the products was proposed.

Recent developments in industrial applications of nanoemulsions

Nanotechnology is being utilized in various industries to increase the quality, safety, shelf-life, and functional performance of commercial products. Nanoemulsions are thermodynamically unstable colloidal dispersions that consist of at least two immiscible liquids (typically oil and water), as well as various stabilizers (including emulsifiers, texture modifiers, ripening inhibitors, and weighting agents). They have unique properties that make them particularly suitable for some applications, including their small droplet size, high surface area, good physical stability, rapid digestibility, and high bioavailability. This article reviews recent developments in the formulation, fabrication, functional performance, and gastrointestinal fate of nanoemulsions suitable for use in the pharmaceutical, cosmetic, nutraceutical, and food industries, as well as providing an overview of regulatory and health concerns. Nanoemulsion-based delivery systems can enhance the water-dispersibility, stability, and bioavailability of hydrophobic bioactive compounds. Nevertheless, they must be carefully formulated to obtain the required functional attributes. In particular, the concentration, size, charge, and physical properties of the nano-droplets must be taken into consideration for each specific application. Before launching a nanoscale product onto the market, determination of physicochemical characteristics of nanoparticles and their potential health and environmental risks should be evaluated. In addition, legal, consumer, and economic factors must also be considered when creating these systems.

Antifungal Role of Common Indian Spices & Herbs: A Narrative Review

Abstract:

A large variety of spices can be found in kitchens worldwide. The usage varies from region to region as per the cuisine. They hold nutritional values and are being exploited for their anticancer, antifungal, antibacterial, antiulcer, anti-inflammatory properties. This study highlights some of the commonly used Indian spices for their antifungal properties and summarizes their potential antifungal activity. Fungal diseases are deep-rooted and cause acute/chronic infections in humans, mainly Aspergillus and Candida species. As the tropical climate provides a breeding ground for fungal infections, such regions share a huge load of mycoses. Various spices have been shown to be effective against treating fungal diseases. The current study focuses on the potential anti-fungal role of the spices and reviews the current literature on the possible mechanism of action of the active compounds of these spices concerning the commonly used antifungal drugs. The spices consist of essential oils that work by inhibition mycotoxin biosynthesis, or disrupting and inhibiting cell wall formation and inhibiting efflux pumps and are comparable to the currently available antifungal drugs.

Antiparasitic effects of Elettaria cardamomum L. essential oil and its main compounds, 1-8 Cineole alone and in combination with albendazole against Echinococcus granulosus protoscoleces

Background

The present investigation aims to determine the chemical structure and protoscolicidal effects of Elettaria cardamomum L. essential oil (ECEO) and its main compounds 1–8 cineole alone and along with albendazole (ALZ) against Echinococcus granulosus protoscoleces in vitro and ex vivo. We also decided to evaluate some cellular mechanisms such as the apoptotic activity and the permeability of plasma membrane of protoscoleces treated with ECEO and 1–8 cineole.

Methods

Hydatid cyst protoscoleces were divided into seven groups including protoscoleces treated with ECEO 50 µl/mL (T1), protoscoleces treated with ECEO 100 µl/mL (T2), protoscoleces treated with ECEO 200 µl/mL (T3), protoscoleces treated with 1–8 cineole 100 µg/mL (T4), protoscoleces treated with 1–8 cineole 200 µg/mL (T5), protoscoleces treated with 1–8 cineole 100 µg/mL + albendazole 50 µg/mL (T6), and protoscoleces treated with 1–8 cineole 200 µg/mL + albendazole ALZ-50 µg/mL (T7). The viability of protoscoleces were recorded by eosin staining examination. Moreover, the induction of apoptosis and the plasma membrane permeability of the protoscoleces treated with ECEO and 1–8 cineole were evaluated.

Results

The highest protoscolicidal effect of ECEO was observed at the dose of 200 µl/ml (T3). 1,8-Cineole alone and combined with ALZ, particularly at the dose of 200 µg/ml (T5 and T7), destroyed the 100% protoscolices after 10 min incubation. The ECEO (T1-T3) and 1–8 cineole alone (T4 and T5) and in combination with ALZ (T6 and T7) took longer to display their protoscolicidal effect ex vivo. The obtained results of relative fuorescent items exhibited that the protoscoleces incubated with ECEO and 1,8-Cineole, alter the permeability of plasma membrane by Sytox Green with increasing the concentration. The findings revealed exhibited that ECEO and 1,8-Cineole increasingly and dose-dependently induced activation of caspase-3 enzyme ranging from 6.8 to 23.3%.

Conclusion

Our obtained results revealed that ECEO and its main compound, 1,8-Cineole exhibited the potent protoscolicidal in vitro and ex vivo; and if more research is done on their efficacy and toxicity in animal models and even clinical setting, it can be suggested as a protoscolicidal agent to use during hydatid cyst surgery.

Decoding antibacterial and antibiofilm properties of cinnamon and cardamom essential oils: a combined molecular docking and experimental study

This study sets out to compare the antibacterial and antibiofilm profiles of Ci/Ca EOs alone and in combination together against infectious bacterial strains. MIC assay was carried out to survey the effectiveness of prepared EOs by two-fold serial dilution method and MTT evaluation. Synergic antibacterial properties of EOs against target strains were studied by using checkerboard titration method. Biofilm growth and development were evaluated using CV and XTT reduction assays. Antibacterial activity was observed for EOs against both bacterial strains with stronger activity for CiEO against both bacteria. The synergistic antibacterial effect was observed only against B. subtilis. Based on the FIC index, combinations could not inhibit the growth of E. coli. The pure EOs and their combination inhibited cell attachment for both studied bacteria with stronger effect on E. coli. CV and XTT reduction assays results showed that Ci EO and its combination with CaEO had the highest antibiofilm activity at lowest MIC value 0.08% and 0.04/0.02% against biofilm formed by E. coli and B. subtilis respectively, indicating a high antibiofilm potential. Computational docking analyses also postulated that the active constituents of evaluated EOs have the potential to interact with different bacterial targets, suggested binding mode of action of EOs metabolites. By and large, synergistic anti-biofilm properties of EOs may provide further options for developing novel formula to inhibit a variety of infectious clinical and industrial strains without (or less) toxicity effects on human body.

Deep Eutectic Solvents (DESs) as Green Extraction Media of Beneficial Bioactive Phytochemicals

Deep eutectic solvents (DES) are a mixture of two or more components and are classified as ionic solvents with special properties such as low volatility, high solubility, low melting points, low-cost materials and are less toxic to humans. Using DES has been suggested as an eco-friendly, green method for extraction of bioactive compounds from medicinal plants and are a safe alternative for nutritional, pharmaceutical and various sector applications. Conventional solvent extraction methods present drawbacks such as long extraction period, safety issues, harmful to the environment, costly and large volume of solvents required. The extraction method with DES leads to higher extraction yield and better bioactivity results as compared to the conventional solvents. This review provides a summary of research progress regarding the advantages of using DES to extract bioactive compounds such as phenolic acid, flavonoids, isoflavones, catechins, polysaccharides, curcuminoids, proanthocyanidin, phycocyanin, gingerols, ginsenosides, anthocyanin, xanthone, volatile monoterpenes, tannins, lignin, pectin, rutin, tert-butyl hydroquinone, chlorogenic acids, resveratrol and others, as opposed to using conventional solvents. The bioactivity of the extracts is determined using antioxidant, antibacterial and antitumor activities. Hence, DESs are considered potential green media with selective and efficient properties for extracting bioactive ingredients from medicinal plants.

Efficacy of zirconium oxide nanoparticles coated on stainless steel and nickel titanium wires in orthodontic treatment

It is of particular intrigue to synthesize, analyze anti-bacterial, anti-inflammatory activity, cytotoxicity effect of clove and cardamom reinforced zirconium oxide nanoparticles to coat the orthodontic archwires and study its ramifications. Characterization of nanoparticles was done using Transmission electron microscopic analysis (TEM). Antimicrobial activity was assessed using agar well diffusion method. Cytotoxic effect was assessed using Brine Shrimp Assay. Anti-inflammatory activity was completed using Bovine Serum Albumin (BSA). A Digital magnetic stirrer with a hot plate was used to coat orthodontic arch wires such as NiTi and SS. TEM spherical shape was of size 5 -20 nm. Minimal cytotoxicity was observed at 50 µL. Anti-inflammatory property was fair. Antimicrobial activity against Lactobacillus species, streptococcus mutans staphylococcus aureus and Candida albicans was recorded. NiTi and SS showed a colour shift from silver to orange red with a uniform surface coating on wires. Thus, green synthesized zirconium oxide nanoparticles have potent antimicrobial, anti-inflammatory properties with minimal cytotoxicity for further consideration as nano-coatings on orthodontic archwires such as NiTi and Stainless Steel.

Graphene-Assisted Sensor for Rapid Detection of Antibiotic Resistance in Escherichia coli

In recent years, antibiotic-resistant bacteria caused by antibiotic abuse in the medical industry have become a new environmental pollutant that endangers public health. Therefore, it is necessary to establish a detection method for evaluating drug-resistant bacteria. In this work, we used Escherichia coli as a target model and proposed a method to evaluate its drug resistance for three antibiotics. Graphene dispersion was used to co-mix with E. coli cells for the purpose of increasing the current signal. This electrochemical-based sensor allows the evaluation of the activity of E. coli on the electrode surface. When antibiotics were present, the electrocatalytic reduction signal was diminished because of the reduced activity of E. coli. Based on the difference in the electrochemical reduction signal, we can evaluate the antibiotic resistance of different E. coli strains.

Effects of Essential Oils of Elettaria cardamomum Grown in India and Guatemala on Gram-Negative Bacteria and Gastrointestinal Disorders

The present study examined the chemical composition and antimicrobial and gastrointestinal activity of the essential oils of Elettaria cardamomum (L.) Maton harvested in India (EC-I) and Guatemala (EC-G). Monoterpenes were present in higher concentration in EC-I (83.24%) than in EC-G (73.03%), whereas sesquiterpenes were present in a higher concentration in EC-G (18.35%) than in EC-I (9.27%). Minimum inhibitory concentrations (MICs) of 0.5 and 0.25 mg/mL were demonstrated against Pseudomonas aeruginosa in EC-G and EC-I, respectively, whereas MICs of 1 and 0.5 mg/mL were demonstrated against Escherichia coli in EC-G and EC-I, respectively. The treatment with control had the highest kill-time potential, whereas the treatment with oils had shorter kill-time. EC-I was observed to be more potent in the castor oil-induced diarrhea model than EC-G. At 100 and 200 mg/kg, P.O., EC-I exhibited 40% and 80% protection, respectively, and EC-G exhibited 20% and 60% protection, respectively, in mice, whereas loperamide (10 mg/kg, i.p., positive control) exhibited 100% protection. In the in vitro experiments, EC-I inhibited both carbachol (CCh, 1 µM) and high K⁺ (80 mM)-induced contractions at significantly lower concentrations than EC-G. Thus, EC-I significantly inhibited P. aeruginosa and E. coli and exhibited more potent antidiarrheal and antispasmodic effects than EC-G.

Anti-biofilm Potential of Elletaria cardamomum Essential Oil Against Escherichia coli O157:H7 and Salmonella Typhimurium JSG 1748

Foodborne pathogens, microbial recurrent infections, and antibiotic resistance have driven researchers to explore natural compounds as safe alternative antimicrobials. In this study, the chemical profile, antimicrobial, and mutagenic activities of the Elletaria cardamomum essential oil were investigated. GC-MS analysis identified the major bioactive components as α-terpinyl acetate, 1,8-cineole, linalool acetate, and sabinene, at concentrations of 34.95, 25.30, 8.13, and 5.48% respectively, of the essential oil's content. Regarding antimicrobial activity, the minimum inhibitory concentration of green cardamom essential oil was 1% against Escherichia coli O157:H7 and Pseudomonas aeruginosa ATCC 14213. Green cardamom essential oil, when used at concentrations of 0.015, 0.031, 0.062, and 0.125% (v/v) prevented biofilm formation of Escherichia coli O157:H7 by 64.29, 65.98, 70.41, and 85.59%, respectively. Furthermore, these concentrations inhibited 6.13, 45.50, 49.45, and 100%, respectively, of the Salmonella Typhimurium JSG 1748 biofilm. A mutagenicity assay confirmed that green cardamom essential oil has no demonstrable mutagenic activity against the tested strains. The study's findings suggest that green cardamom derived bioactive compounds are safe organic antimicrobials, effective in controlling biofilm formation by Gram-negative pathogens. Moreover, such compounds could possibly be used in the food industry (e.g., bakery, dairy, meat, and other food products) as a safe alternative to chemical preservatives (antimicrobials) to enhance shelf life by improving the antimicrobial status while at the same time imparting a pleasant and appealing aroma for consumers.

Chemometrics-based aroma profiling for revealing origin, roasting indices, and brewing method in coffee seeds and its commercial blends in the Middle East

Coffee is among the most consumed beverages worldwide. The present study reports on the aroma composition associated with coffee seeds brewing. Aroma of authentic coffee specimens of Coffea arabica and C. robusta alongside with typical products consumed in the Middle East were analyzed using HS-SPME coupled with GC-MS. In addition, multivariate data analysis (MVA) was employed. Results revealed for 102 volatiles with a distinct aroma profile between the different brewing methods. Infusion demonstrated higher esters level, while decoction and maceration were more abundant in sesquiterpenes and terpene alcohols, respectively. Besides, heat-induced products, i.e., 4-vinyl guaiacol was identified as potential roasting index in instant coffee and roasted C. robusta brews. Blending with cardamom further masked the smoky odor of such compounds by its fragrant terpinyl acetate. This study provides the first report on the chemical sensory attributes of Middle Eastern coffee blends and further reveal for the impact of brewing, roasting on its aroma composition.

Nutritional, Antioxidant, Antimicrobial, and Toxicological Profile of Two Innovative Types of Vegan, Sugar-Free Chocolate

Increased sugar consumption and unhealthy dietary patterns are key drivers of many preventable diseases that result in disability and death worldwide. However, health awareness has increased over the past decades creating a massive on-going demand for new low/non-caloric natural sweeteners that have a high potential and are safer for consumption than artificial ones. The current study aims to investigate the nutritional properties, in vitro toxicological profile, total/individual polyphenols content, and the antioxidant, anti-cariogenic, and antimicrobial activity of two newly obtained vegan and sugar-free chocolate (VHC1 and VHC2). The energy values for the two finished products were very similar, 408.04 kcal/100 g for VHC1 and 404.68 kcal/100 g for VHC2. Both products, VHC1 and VHC2 present strong antioxidant activities, whereas antimicrobial results show an increased activity for VHC1 compared to VHC2, because of a higher phenolic content. In vitro toxicological evaluation revealed that both samples present a safe toxicological profile, while VHC2 increased cellular turnover of dermal cell lines, highlighting its potential use in skin treatments. The current work underlines the potential use of these vegetal mixtures as sugar-free substitutes for conventional products, as nutraceuticals, as well as topic application in skin care due to antimicrobial and antioxidant effects.

Black cardamom essential oil prevents Escherichia coli O157:H7 and Salmonella Typhimurium JSG 1748 biofilm formation through inhibition of quorum sensing

This study aimed to investigate the chemical composition, using GC-MS, and anti-biofilm potential of black cardamom essential oil (BCEO) against biofilms of Escherichia coli O157:H7 and Salmonella Typhimurium JSG 1748 through inhibition of bacterial quorum sensing. GC-MS quantification demonstrated that BCEO contains 1,8-cineole (44.24%), α-terpinyl acetate (12.25%), nerolidol (6.03%), and sabinene (5.96%) as the major bioactive compounds. Antioxidant assays for BCEO revealed the total phenolic and flavonoid mean values were 1325.03 ± 7.69 mg GAE 100/g and 168.25 ± 5.26 mg CE/g, respectively. In regards to antimicrobial potential, Candida albicans was the most sensitive species compared to Streptococcus mutans, Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, and Salmonella Typhimurium with the following zones of inhibition; 14.4 ± 0.52, 13.2 ± 0.42, 11.2 ± 0.28, 11.0 ± 0.52, 8.2 ± 0.24 and 6.6 ± 0.18 mm in diameter, respectively. Biofilm inhibition by BCEO was concentration-dependent, when various concentrations of 0.03, 0.06, 0.12, 0.25 and 0.5% were applied, 33.67, 34.14, 38.66, 46.65 and 50.17% of Salmonella Typhimurium biofilm was inhibited, while 47.31, 54.15, 76.57, 83.36 and 84.63% of Escherichia coli biofilm formation was prevented. Chromobacterium violaceum ATCC 12,472 and its product violacein, was used as a microbial indicator for enhancement or inhibition of quorum sensing. Our data showed that 0.5% of BCEO inhibited violacein production without influencing the growth of Chromobacterium violaceum, while 1% of BCEO, caused 100% inhibtion of violacein production together with 30% inhibition of growth. This study shows that BCEO possesses promising antioxidant and antimicrobial potential, and found anti-biofilm activities linked to the quenching of the quorum sensing system of E. coli and S. Typhimurium.

Anti-quorum sensing and biofilm inhibitory activity of Apium graveolens L. oleoresin

Apium graveolens L. (Apiaceae) is a dietary herb used as a spice, condiment and medicine. A. graveolens (Celery) has been studied for its antimicrobial property and for its application as flavours in food industry. The present study investigated the Apium graveolens oleoresin as an anti-quorum sensing and antibiofilm agent. The quorum sensing and biofilm inhibition study was carried out using biosensor strains Chromobacterium violaceum CV12472 and Pseudomonas aeruginosa PAO1. The MIC of celery oleoresin against C. violaceum CV12472 and P. aeruginosa PAO1 was 10 and 25% v/v, respectively. Inhibition of violacein and biofilm formation was tested at concentrations of oleoresins ranging from 1.56 and 50% v/v. The oleoresins showed a concentration dependent QS inhibitory activity and at sub-MIC of 6.25 and 12.5% v/v, the oleoresins significantly inhibited violacein production and biofilm formation (p < 0.05). Similarly, the celery oleoresin had significant QS modulatory effect on swimming, swarming and twitching motility in P. aeruginosa PAO1 at 12.5% v/v (p < 0.05). The major phytoconstituents present in celery oleoresin as analysed by GC-MS were eicosadiene, benzenemethanol and methyl ester which have not been previously reported. The findings suggest that celery has QS and biofilm inhibitory potential against gram negative pathogens and can find application as food intervention techniques.

Electrospun chia seed mucilage/PVA encapsulated with green cardamonmum essential oils: Antioxidant and antibacterial property

In this work, the potential of chia seed mucilage (CSM) as a new source of carbohydrate for encapsulation of green cardamonmum Essential oils (GCEOs) was evaluated. ¹H NMR spectrum, FTIR spectrum and, SEM image has confirmed the existence of the GCEOs in the nanofibers. The nanofibers of CSM and polyvinyl alcohol have not antibacterial property, while nanofibers containing GCEOs show antibacterial activity against E. coli and S. aureus. Incorporating GCEOs in CSM nanofibers improved the antioxidant of the generated nanofibers. The amount of radical scavenging for the nanofibers containing 16 (mg/ml) of GCEOs was 18% and increasing the GCEOs concentration up to 64 (mg/ml) leads to grow the activity up to 41%. Thus, our studies indicate that nanofiber can be used as a novel antioxidant and antibacterial agent in the food and pharmaceutical industry.

Antivirulence properties and related mechanisms of spice essential oils: A comprehensive review

In recent decades, reduced antimicrobial effectiveness, increased bacterial infection, and newly emerged microbial resistance have become global public issues, leading to an urgent need to find effective strategies to counteract these problems. Strategies targeting bacterial virulence factors rather than bacterial survival have attracted increasing interest, since the modulation of virulence factors may prevent the development of drug resistance in bacteria. Spices are promising natural sources of antivirulence compounds owing to their wide availability, diverse antivirulence phytochemical constituents, and generally favorable safety profiles. Essential oils are the predominant and most important antivirulence components of spices. This review addresses the recent efforts of using spice essential oils to inhibit main bacterial virulence traits, including the quorum sensing system, biofilm formation, motility, and toxin production, with an intensive discussion of related mechanisms. We hope that this review can provide a better understanding of the antivirulence properties of spice essential oils, which have the potential to be used as antibiotic alternatives by targeting bacterial virulence.

Quorum sensing system: Target to control the spread of bacterial infections

Quorum Sensing (QS) systems regulate the gene expression of different types of virulence factors in accordance with the cell population density. A literature search was performed, including electronic databases such as MEDLINE/PubMed, SciELO, and LILACS, as well as other databases not indexed, such as Google Scholar. The search was conducted between July 2018 and April 2019, through online research. Antimicrobial resistance is one of the biggest threats to global health and the dissemination of resistant microbes in the environment is a major public health problem. Therefore, it is important to develop new therapies to control the spread of resistant bacteria to humans. Thus, interference in the chemical signal (autoinducers) of the QS system has been postulated as a good alternative, technically known as "Quorum Quenching" or QS inhibitors. Inhibition of QS signaling is not intended to kill the microorganism, but to block the expression of the target genes, making the cells less virulent and more vulnerable to host immune response. Anti-virulence therapy by agents that interfere with this system in pathogenic bacteria is a well-studied strategy, including medicinal plants and their bioactive constituents, and presents good prospects. This review aims to provide an overview of the QS system in bacteria and describe the main inhibitors of the system.

Botany, traditional uses, phytochemistry and biological activities of cardamom [Elettaria cardamomum (L.) Maton] - A critical review

ETHNOPHARMACOLOGICAL RELEVANCE

Small cardamom [Elettaria cardamomum (L.) Maton. (Family: Zingiberaceae)] capsules (fruits) have been used for traditional medicine applications including for the control of asthma, teeth and gum infections, cataracts, nausea, diarrhea, as well as cardiac, digestive and kidney disorders. The versatile use of cardamom capsules has several other beneficial health effects that are relevant in light of traditional and modern pharmaceutical perspectives.

AIM OF THE STUDY

This review aims to provide a critical and comprehensive evaluation of the traditional and current medical uses of E. cardamomum, and compare these applications with modern research studies. This critical review also discusses the botanical distribution, phytochemical constituents and biological activities of cardamom capsule extracts and essential oil.

MATERIALS AND METHODS

An online survey was conducted of the traditional uses, phytochemical composition, and pharmacological applications of cardamom essential oil (CEO) and extracts. Pertinent data were obtained from several electronic scientific databases (Science Direct, Elsevier, Web of Science, PubMed, Springer, ACS publications, Taylor and Francis, Wiley On-line Library and Google Scholar), and additional information was obtained from textbooks and local prints and scripts.

RESULTS

Cardamom fruits (capsules) are used widely as a spice and flavoring ingredient in foods, and are often recognized for their beneficial health properties. They are also used in fragrances. Phytochemical analyses have described important chemical constituents of cardamom including carbohydrates, proteins, minerals, lipids, essential oils, flavonoids, terpenoids and carotenoids. CEO has several biological roles including antioxidant, antidiabetic, antibacterial, anticancer, gastro-protective and insecticidal activities.

CONCLUSION

The widespread availability and recommendation of synthetic compounds for addressing human health have several side effects besides higher costs. Hence, examining natural bioactive compounds is imperative. This review investigates and presents the pertinent information on cardamom and its traditional uses, as well as potential pharmacological properties of CEO and extracts. Additional research studies are needed to understand the mechanism of action of bioactive constituents.

Systematics Evaluations of Morphological Traits, Chemical Composition, and Antimicrobial Properties of Selected Varieties of Elettaria cardamomum (L.) Maton

Elettaria cardamomum is cultivated in the Southern part of India showed great extinct of differences in their morphotypes and chemical compositions. In the present study, we have selected three varieties of Elettaria cardamomum “Valley Green, Palakuzhi, and ICRI”, to analyze the morphological perturbations, chemical compositions, and antimicrobial activities. The differences in the morphological character of cardamom varieties (Valley Green, Palakuzhi, and ICRI) were carried out on the basis of panicles, capsules shape, plant height, tiller, and seeds per capsule. The GC-MS analysis of the essential oils resulted in the identification of 27, 29, 30 compounds representing over 97.4%, 95.2%, and 98.8% of the Valley Green (VG), Palakuzhi (PAL), and ICRI fruit oils respectively. Monoterpene, α-terpinyl acetate varied from 35.4 to 47.5%, a major constituent while 1,8-cineole (22.8% to 27.4%) observed the second major compounds revealed in oils of these cultivars. Further, the antimicrobial activities of each essential oils were performed against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Candida albicans, and Aspergillus niger. The maximum inhibition percentage against the microbes was observed in Valley Green essential oil as compared to oils of other varieties.

Antibacterial Activity and Anti-Quorum Sensing Mediated Phenotype in Response to Essential Oil from Melaleuca bracteata Leaves

The prominent antibacterial and quorum sensing (QS) inhibition activity of aromatic plants can be used as a novel intervention strategy for attenuating bacterial pathogenicity. In the present work, a total of 29 chemical components were identified in the essential oil (EO) of Melaleuca bracteata leaves by gas chromatography-mass spectrometry (GC-MS). The principal component was methyleugenol, followed by methyl trans-cinnamate, with relative contents of 90.46% and 4.25%, respectively. Meanwhile, the antibacterial activity and the QS inhibitory activity of M. bracteata EO were first evaluated here. Antibacterial activity assay and MIC detection against seven pathogens (Dickeya dadantii Onc5, Staphylococcus aureus ATCC25933, Pseudomonas spp., Escherichia coli ATCC25922, Serratia marcescens MG1, Pseudomonas aeruginosa PAO1 and Chromobacterium violaceum ATCC31532) demonstrated that S. aureus ATCC25933 and S. marcescens MG1 had the higher sensitivity to M. bracteata EO, while P. aeruginosa PAO1 displayed the strongest resistance to M. bracteata EO. An anti-QS (anti-quorum sensing) assay revealed that at sub-minimal inhibitory concentrations (sub-MICs), M. bracteata EO strongly interfered with the phenotype, including violacein production, biofilm biomass, and swarming motility, as well as N-hexanoyl-L-homoserine lactone (C6-HSL) production (i.e., a signaling molecule in C. violaceum ATCC31532) of C. violaceum. Detection of C6-HSL indicated that M. bracteata EO was capable of not only inhibiting C6-HSL production in C. violaceum, but also degrading the C6-HSL. Importantly, changes of exogenous C6-HSL production in C. violaceum CV026 revealed a possible interaction between M. bracteata EO and a regulatory protein (cviR). Additionally, quantitative real-time polymerase chain reaction (RT-qPCR) analysis demonstrated that the expression of QS-related genes (cviI, cviR, vioABCDE, hmsNR, lasA-B, pilE1, pilE3, and hcnB) was significantly suppressed. Conclusively, these results indicated that M. bracteata EO can act as a potential antibacterial agent and QS inhibitor (QSI) against pathogens, preventing and controlling bacterial contamination.

Isolation and characterization of cyclic lipopeptides with broad-spectrum antimicrobial activity from Bacillus siamensis JFL15

In this research, the antimicrobial substance anti-JFL15 was partially purified using a simple two-step extraction process from the cell-free supernatants of Bacillus siamensis JFL15. Anti-JFL15 exhibited a strong antibacterial activity against various multidrug-resistant aquatic bacterial pathogens, including Escherichia coli, Edwardsiella tarda, Pseudomonas aeruginosa, Aeromonas hydrophila, and Vibrio. Liquid chromatography-mass spectrometry revealed that anti-JFL15 contained eight cyclic lipopeptides belonging to two families: bacillomycin F (m/z 1056.56-1084.59) and surfactin (m/z 1007.65-1049.70) analogs. PCR analysis showed the presence of genes (i.e., sfp gene, surfactin synthetase D, fengycin synthetase B, iturin synthetase A, iturin synthetase C and bacillomycin synthetase D) involved in the biosynthesis of cyclic lipopeptides. This study is the first to identify cyclic lipopeptides from B. siamensis and use them to suppress the growth of various multidrug-resistant aquatic bacterial pathogens. Results indicated that B. siamensis JFL15 is a promising biocontrol agent for the effective and environmentally friendly control of various multidrug-resistant aquatic bacterial pathogens.