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Plant materials continue to play a major role in primary health care as therapeutic remedies in many developing countries. Medicinal herbs contain physiologically active principles that over the years have been exploited in traditional medicine for the treatment of various ailments as they contain antimicrobial properties. This paper aims to determine the antibacterial activity of Iranian endemic plants.

Antibacterial activities of ethanol extract and essential oil of ten Iranian folklore herbs including Heracleum lasiopetalum Boiss., Hypericum scabrum L., Thymus daenensis Celak., Ziziphora teniur L., Echiophora platyloba L., Dracocephalum multicaule Benth., Kelussia odoratissima Mozff., Mentha longifolia Hudson., Achillea kellalensis Boiss. and Arnebia euchroma (Royle.) Johnston. were investigated against Yersinia enterocolitica PTCC 1151 by agar disc diffusion and serial dilution assays.

Most of the extracts and essential oils showed some antibacterial activity against the tested bacteria with the diameter of inhibition zone ranging between 9 and 16 mm. Of the plants studied, the most active extracts were those obtained from essential oil of H. lasiopetalum fruits and ethanol extract of A. euchroma roots. The MIC values for active extract and essential oil ranged between 0.039 and 0.156 mg/ml.

The results obtained appeared to confirm the antibacterial potential of the plants investigated.

The essential oil <0.039 mg/ml of H. lasiopetalum fruits could be used as natural antibacterial agent Y. enterocolitica in the food preservation and human health.

The purpose of this paper is to provide a comprehensive overview of multiple functions of the coriander plant, including its nutritional and nutraceutical benefits, with special reference to linalool.

The authors undertake a literature review of the coriander plant's history, chemical composition of coriander parts and its oil, and their nutraceutical potential. Various phytopharmacological appraisals have been discussed at length to investigate their important potential.

Coriander is an annual, herbaceous plant which originated from the Mediterranean and Middle Eastern regions and known as medicinal plants. Coriander contains an essential oil (0.03‐2.6%). The different parts of this plant contain monoterpenes, limpnene, α‐pinene, γ‐terpinene, p‐cymene, citronellol, borneol, camphor, coriandrin, geraniol, dihydrocoriandrin, coriandronsA‐E, flavonoids and essential oils. It is used as a stomachic, spasmolytic and carminative which have a greater bioactive property. Various parts of this plant, such as seeds, leaves, flower and fruit, possess antioxidant activity, diuretic, anti‐convulsant anti‐diabetic activity, sedative hypnotic activity, anti‐mutagenic, anti‐microbial activity, anthelmintic activity. The physical properties, chemical composition and bioactivity affect the coriander's commercial value.

Currently available information on coriander seeds and leaves is insufficient. These observations have led to continuing research aimed at identifying specific bioactive components in foods, such as antioxidants, which may be responsible for improving and maintaining health. Antioxidants are present in foods as vitamins, minerals, carotenoids, and polyphenols. Coriander is also rich in such compounds. Research supports that some of these foods, as part of an overall healthful diet, have the potential to delay the onset of many age‐related diseases, so there is urgent need to explore the role of these compounds.

This review is unique in its comprehensive nature and reflects the importance of coriander as a medicinal food.

The purpose of this study is to establish a suitable procedure for dyeing and multifunctional finishing on 100% cotton using extracts of eucalyptus leaves in an eco-friendly manner.

Box–Behnken design of experiments and analysis of variance (ANOVA) were used to optimise the conditions of extraction, dyeing and finishing. Phytochemical analysis was performed to determine the chemical constituents of the extracts. Colour strength, fastness properties were evaluated for dyed fabric samples. The effectiveness of eucalyptus leaves extract as an insect repellent, aroma, antibacterial finishing agent, was assessed. Pre-soaking and padding method was used for the application of active essential oil on the fabric.

Essential oil extracted from Eucalyptus globulus leaves have great repellent rate for insects to the extent of 90% and aroma intensity of 72% and antibacterial effect of 100% bacterial reduction up to five washings. The use of citric acid as cross-linking agent helps increase the durability of the finish. Natural dyeing to get light yellow shade is possible with extracts made with water, possessing good fastness properties.

Scaling up the extraction process and soaking larger quantities of fabrics in extracted essential oil solution before the pad applications are considered limitations of this study. However, smaller pieces of fabrics can conveniently be handled in this process. It has tremendous potential for practising industrially, to get yellow-shaded multifunctional finished cotton textiles.

Protection against insects, including mosquitoes, bacteria with additional aroma on cotton will be of great use in day-to-day life for the wearer.

Eco-friendly, renewable sources of ingredients from the plant were used to obtain protection against pathogenic or odour-causing microorganisms using this hygiene finish with multiple end uses.

This original work enables conducting dyeing and multifunctional finishing together in a single stage, which otherwise takes a number of steps, consuming large quantities of water, chemicals and energy to impart similar effects on cotton.

Banana is an important tropical fruit with high demand in the market. The ripe fruits are less resistant to transport making logistics difficult. Moreover, as a climacteric fruit, it has a short post-harvest shelf life. Edible coatings/films, including active substances, have been used as an alternative for preserving fruits and vegetables during post-harvest period. The purpose of this study was to evaluate the incorporating clove essential oil on the properties of cassava starch films and their effect on the post-harvest quality of different banana varieties.

Cassava starch films incorporating clove essential oil were developed and the films were characterized with respect to moisture, thickness, solubility, water vapor permeability (WVP), biodegradability, color and in vitro antifungal activity. Cultivars such as Prata-Anã, Grand Nine, BRS Tropical and BRS Conquista were coated with cassava starch, cassava starch film with clove essential oil (CSEO) and polyvinyl polychloride (PVC). The quality of fruits was monitored during eight storage days using mass loss, total soluble solids content (TSS) and titratable acidity (TTA).

Incorporation of clove essential oil significantly increased film thickness, reduced moisture content, solubility and WVP (p < 0.05) and did not affect the biodegradability and color of the films. The essential oil incorporated films showed antifungal activity against the fungi Colletotrichum gloeosporioides and Colletotrichum musae, but not against the yeast Saccharomyces bourladii. CSEO and PVC coating were more efficient in reducing the mass loss, SS content and TTA of the coated fruits in all varieties studied. Both CSEO and PVC coatings improve the quality attributes such as TSS and TTA and reduced mass loss, of the banana varieties such as Prata-Anã, Grand Nine, BRS Tropical and BRS Conquista during storage.

The active film with essential oil showed antifungal activity and essential oil can be incorporated into other food systems. This study approaches a new possibility of film coating with essential oil for a banana that showed minimum weight loss and satisfactory quality and increased shelf life. This film coating demonstrates biodegradable characteristics that could be eco-friendly and sustainable to consumers.

This study aims at improving combustion process to reduce emissions. Emissions such as carbon monoxide, particulate matter and unburnt hydrocarbons are a result of incomplete combustion. These emissions have useful energy but cannot be reclaimed. Hence, to enhance combustion, effect of biofuel blending on diesel combustion was investigated.

Essential oils have been found easier for blending with diesel because of simple molecular structure compared to vegetable oils. Lavender oil is an essential oil which has not yet been studied by blending with diesel. The major constituents of lavender oil are linalyl acetate (cetane number improver) and linalool (nitrogen oxides reduction). A single-cylinder, four-stroke diesel engine was run by blending diesel with lavender oil (Lavandula angustifolia oil [LAO]) in varying proportions, 5%, 10% and 15% by volume.

Higher heat release rate (HRR) was observed using lavender oil blends compared to pure diesel. Compared to diesel, an increase in brake-specific fuel consumption using blends was observed. LAO15 has the lowest CO emissions at all loading conditions, 29.3% less at 100% load compared to diesel. LAO5 and LAO15 have 6.9% less HC emissions at 100% load condition compared to diesel. LAO15 has only 1.3% higher NO_x emissions compared to diesel at 100% load condition. LAO5 has the lowest smoke content at all loading conditions.

Lavender oil was used directly without any processing. Tested on single-cylinder engine.

To the best of the author’s knowledge, currently, there is no published work on lavender oil–diesel combination. Lavender oil can provide a simple renewable solution for diesel additives with potential up to 15% blending.

This paper is aimed at food science or biology students planning a practical independent study into the antimicrobial properties of spices and academic staff wishing to develop a straightforward and reproducible practical activity.

Disc‐diffusion assays are used to investigate the antimicrobial activity of cinnamon and cloves against two bacteria Escherichia coli B and staphylococcus albus and a yeast Saccharomyces cerevisiae. Aqueous and alcoholic extracts of the spices and alcoholic extracts of their essential oils are examined. Minimum inhibitory concentrations of alcoholic extracts of both spices and oils are also determined.

Both spices demonstrated microbial inhibitory effects; alcoholic extracts had greater activity than aqueous extracts. Additionally, essential oils had greater activity than the spices. Minimum inhibitory concentrations were smaller with the oils than with the spices.

Although the research for this paper involved just two spices, such is the size of the plant kingdom that there are wide opportunities for further investigations using this procedure.

Disc‐assays were found to be a simple, cheap and reproducible practical method. For this paper, micro‐organisms available for educational purposes were used; however, other organisms could be investigated depending upon available microbiological expertise and facilities.

The results demonstrate that the antimicrobial effects of spices and particularly their essential oils can be examined using disc‐diffusion assay. The method provides many opportunities for student investigation.

Small and medium enterprises (SMEs) involved in the production of natural essential oils can reduce market accessibility challenges by trading through electronic marketplaces (e-marketplaces). However, trust is a barrier that SMEs should overcome in order to successfully trade in e-marketplaces. The agricultural sector presents a unique challenge to the subject of trust and e-marketplaces. It is difficult for SMEs in the agricultural sector to provide the level of assurance of product quality that their buyers expect. Trust between buyers and sellers during the earliest stages of e-marketplace interaction can pave the way for future trust in a seller on an e-marketplace. Thus, this study uses the uncertainty reduction theory (URT) to investigate factors that could influence the initial trust and pave the way for future trust in a seller on e-marketplaces. This study assumes a qualitative research methodology in which a multiple-case study approach is adopted. The study focuses on SMEs that produce natural essential oils in South Africa. Open-ended interviews were conducted with companies involved in buying or selling natural essential oils in South Africa to determine the factors that influence their decision to buy or sell in an e-marketplace. Findings from data were used to inform the development of a model of trust in sellers of natural essential oils in e-marketplaces. The proposed model recommends trust factors that should be considered during the entry, personal, and exit phases of the URT. The model identifies common and unique trust factors that relate specifically to businesses trading natural essential oils on e-marketplaces. The study found that some SMEs face challenges in coming up with an effective model for selling agricultural produce on e-marketplaces. Hence, they often resort to face-to-face interaction when it comes to product inspection, especially when dealing with first-time buyers. However, this study presented measures put in place by other SMEs suggesting how such challenges could be addressed. Nevertheless, a lack of trust in technology remains a cause for concern to some SMEs selling natural essential oils.

The efforts of researchers in the 21st century have been devoted to developing novel approaches to leave planet earth green for future generations. This study aims to report the synthesis of microcapsules from natural essential peppermint oil and their application to a bleached polyester and cotton (PC) blended fabric.

Microcapsules were prepared by a complex coacervation process and applied through the conventional pad-dry-cure method. The liquid suspension of the microcapsules was examined by optical microscopy to investigate the surface morphology of the microcapsules. Scanning electron microscopy was used to examine the surface morphology of the fabric after the application of the microcapsules. The finished fabric was checked for its mosquito repellent activity at the lab scale using a standard test protocol (cage test) by inserting a human arm and hand enfolded with microcapsules treated fabric.

PC fabric treated with 6% microencapsulated peppermint oil at zero wash showed 95.3% repellency against mosquitoes, and after 30 washes, the repellency was 85.8% which confirmed the durability of the developed finished fabric. The finished samples exhibited excellent air permeabilities and absorbencies.

This study successfully developed peppermint oil microencapsulated fabric with excellent efficacy against three mosquito species.

The inclusion of natural antioxidants and nanoparticles into edible coatings can improve their structure, functionality and applicability in foods. This study aims to determine the antibacterial effect of new nano-composite based on bean pod shell gum (BPSG), silver nanoparticle (SNP) and herbal essential oil (EO).

For this purpose, BPSG (4 per cent w/v), SNP (0.5-1 per cent w/v) and Helichrysum arenarium EO (1-2 per cent v/v) were mixed. After preparation the edible film, the antibacterial activity was tested on five food-borne pathogenic bacteria in two categories including two-gram positives and three-gram negatives bacteria. The EO composition was determined by GC–mass spectrometry and the antibacterial activity was tested using disk diffusion test.

Results showed that gram-positive bacteria were more susceptible than gram-negative bacteria. Increasing Helichrysum arenarium EO and SNP content increased antimicrobial activity of the edible film based on BPSG, so that the treatment containing 2 per cent v/v Helichrysum arenarium EO and 1 per cent w/v SNP led to the highest inhibition zone (8.1-13.1 mm) compared to treatment containing 1 per cent v/v Helichrysum arenarium EO and 0.5 per cent w/v SNP with inhibition zone range of 5.4-9.9 mm and the difference was statistically significant (p = 0.41). Also, the chemical composition analysis of the EO identified a total of 38 compounds in which a-pinene (32 per cent), 1,8-cineole (16 per cent), α-humulene (15 per cent) and ß-caryophyllene (8 per cent) were the main fractions. Other separated components accounted less than 29 per cent of the oil.

In general, SNP and Helichrysum arenarium EO improved the functional properties including the antimicrobial activity of the edible film based on BPSG, which increases the potential to be used as active packaging for fresh products.

Oxidative rancidity is a major problem in chicken meat because of its higher content of polyunsaturated fatty acids. Besides this, microbial contamination is also one of the major problems of chicken meat which leads to deterioration in quality during storage. Therefore, the purpose of this paper is to investigate anti-microbial and anti-oxidant effects of various blends of essential oils (EOs) on the quality of emulsion-based (ready-to-eat) chicken sausages.

Sausages were incorporated with optimum level of four different blends of EOs containing six different EOs (Clove oil, Holybasil oil, Thyme oil, Cassia oil, Ajowan oil and Beetel oil), namely, Blend-1 (0.25 per cent), Blend-2 (0.25 per cent), Blend-3 (0.25 per cent) and Blend-4 (0.125 per cent); vacuum packaged and stored at −18±1°C for 60 days. Duplicate samples were taken for each parameter, and three trials were conducted for each experiment, total being six observations (n=6) for consistency of the results.

Significant decrease (p<0.05) in pH of control products was observed at each interval of storage period; however, in case of treatment products, significant decrease (p<0.05) was noticed from day 30 onwards. Blend-2 was observed with significantly lower (p<0.05) thio-barbituric acid reacting substances followed by Blend-1. Significantly lower (p<0.05) total phenolics content was observed in Blend-4 products as compared to other treatments. Regarding DPPH activity, control products showed significant decrease (p<0.05); however, in case of treatment products, DPPH activity showed significant (p<0.05) decrease after day 15 of storage. Microbial count increased with progressive storage period; however, the counts were well below the permissible limit of frozen meat products. All the blend incorporated products received very good sensory scores in consistent manner.

The work under this study would be very useful for the meat processing industries dealing with the perishable meat products. Use of natural anti-oxidants will also restore faith towards the consumers who are becoming more health conscious day by day.

The research work is original.