Antibacterial activity of eucalyptus oils

The antibacterial properties of plant volatile oils have been recognised since antiquity and have been rediscovered in more recent times. Eucalyptus leaf oils have received attention in a number of studies. Deans and Ritchie () examined the antibacterial effects of fifty volatile oils purchased from a commercial supplier, including eucalyptus, on twenty-five different bacterial genera. The culture collection consisted of food spoilage, food poisoning, human, animal and plant disease types, along with indicators of faecal pollution and secondary opportunist pathogens. Eucalyptus oil was most effective against Elavobacterium suaveolens and the dairy organism Leuconostoc cremoris. However, it was not amongst the ten most inhibitory oils (thyme, cinnamon, bay, clove, bitter almond, lovage, pimento, marjoram, angelica and nutmeg). Leaf oils from eight Brazilian-grown eucalypts were tested against Mycobacterium avium by Leite et al. (): E. botryoides, E. camaldulensis, Eucalyptus citriodora, E. deglupta, Eucalyptus globulus, E. grandis, E. maculata and E. tereticornis. M. avium was sensitive to all the oils at 10mg/ml but only four of them at 5 mg/ml: Eucalyptus citriodora, E. maculata, E. camaldulensis and E. tereticornis. Read more […]

The Essential Oil of Caraway

The essential oil is obtained mainly of caraway fruits by steam or hydrodistillation. A good overlook about different distillation facilities is given by Lawrence (). The oil is colourless or slightly yellowish and toxic to humans even in relatively low amounts. Amounts of 4g can already cause health disturbances for adults (). Carvone may also cause allergic effects (). Instead of distillation of the ripe whole caraway fruit, it is also possible to chaff the umbels directly from the field into a container which is afterwards directly connected on a distillation unit. The essential oil yield gained in such a way was in the experiments of Hannig et al. () about 481/ha. The early harvest had no negative influence on the oil composition (60% carvone in biannual caraway). Average essential oil yield (assessed on laboratory scale by Dachler et al. () in variety tests) was around 70kg/ha, with top yields of 160kg/ha. In the contrary to earlier reported carvone contents () they observed only 30–48% carvone in the tested biannual varieties. Bazata et al. () found, that during the distillation process the relation of carvone and limonene changed. At the beginning of the distillation the essential oil had higher amounts Read more […]

Turmeric as Spice and Flavorant

  Spices are the plant products or a mixture thereof free from extraneous matter, cultivated, and processed for their aroma, pungency, flavor and fragrance, natural color, and medicinal qualities or otherwise desirable properties. They consist of rhizomes, bulbs, barks, flower buds, stigmata, fruits, seeds, and leaves of plant origin. Spices are food adjuncts, which have been in use for thousands of years, to impart flavor and aroma or piquancy to foods. They are used to prepare culinary dishes and have little or no nutritive value, but they stimulate the appetite, add zest for food, enhance the taste, and delight the gourmet. As there is a need to reduce the fat, salt, and sugar used in food preparation for health reasons, it becomes critical to pay attention to alternative ways to enhance the natural flavors of foods. Value can also be added to meals by enhancing and improving presentation and by using appropriate garnishes. The primary function of a spice in food is to improve its sensory appeal to the consumer. Food presentation is the arrangement of food on a plate, tray, or steam line in a simple appetizing way. This is generally accomplished by imparting its own characteristic color, flavor, aroma, and Read more […]

Syringa vulgaris L. (Common Lilac)

Syringa vulgaris L., or common lilac is a horticulturally important member of the Oleaceae, a family in which other economically significant genera (Olea, Fraxinus, Jasminum, Forsythia) also occur. Thirty species of Syringa are found distributed across the temperate and south temperate zones of Europe and Asia, while the common lilac has been introduced even more widely as an ornamental. A woody shrub (or small tree) in habit, lilac is typical of the Oleaceae in having opposite leaves, a calyx of four fused sepals and a corolla of four united petals. The highly scented flowers occur in thyrses, each branch bearing a terminal flower. The high demand for common lilac and lilac hybrids in the woody ornamental trade has led to several studies of in vitro propagation of this and related species. New shoot formation could be induced from explants of actively growing shoot tips on MS medium supplemented with 0.1 mg/1 6-benzylaminopurine (BA) and 0.1-0.5 mg/1 indoleacetic acid. These were multiplied on MS medium containing high (7.5 mg/1) levels of BA and low (0.1 mg/1) levels of auxin (NAA). Low cytokinin levels led to callus formation, from which regeneration has yet to be reported in lilac. Successful in vitro multiplication Read more […]

The Medicinal Uses of Thyme

The uses of thyme, Thymus vulgaris and other Thymus species are well known, and extensive parts of the world get benefit from this plant group in medicinal and non-medicinal respects. Following the development of the medicinal uses of thyme we can see that thyme has changed from a traditional herb to a serious drug in rational phytotherapy. This is due to many pharmacological in vitro experiments carried out during the last decades, and even a few clinical tests. The studies have revealed well defined pharmacological activities of both, the essential oils and the plant extracts, the antibacterial and spasmolytical properties being the most important ones. The use of thyme in modern phytotherapy is based on this knowledge, whereas the traditional use of thyme describes only empirical results and often debatable observations. Therefore it seems necessary to present here the data available on the pharmacodynamics of thyme and thyme preparations in order to substantiate the use of thyme in modern medicine. The non-medicinal use of thyme is no less important, because thyme (mainly Thymus vulgaris) is used in the food and aroma industries. It serves as a preservative for foods and is a culinary ingredient widely used as Read more […]

Pharmacological Effects of Thyme

Antimicrobial effects of thyme essential oils and thyme preparations Antibacterial effects The first researcher who attributed antibacterial properties to thyme (without specifying the species) was Chamberlain in 1887, after observing the antibacterial effect of its “vapours” on Bacillus anthracis. Since then, numerous studies with essential oils of different species of Thymus have been carried out. They were shown to inhibit a broad spectrum of bacteria, generally Gram-positive bacteria being more sensitive than Gram-negative bacteria. This became obvious in some screening studies administering Thymus oils to a variety of bacteria. Recently the antibacterial activity of thyme (Thymus vulgaris) oil against some important food-borne pathogens, namely Salmonella enteritidis, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Campylobacter jejuni, was tested. The latter was found to be the most resistant of the bacteria investigated. In another study it was shown that the essential oil of thyme and especially its phenols, thymol and carvacrol, have antibacterial acivity against periodontopathic bacteria including Actinobacillus, Capnocytophaga, Fusobacterium, Eikenella, and Bacteroides species, and Read more […]

Pharmacology of Black Pepper

Many spices used in food seasoning have broad spectrum of antimicrobial activity. Their antioxidant activity against lipid peroxidation enhances the keeping quality of food. Apart from the use as a popular spice and flavouring substance, black pepper as drug in the Indian and Chinese systems of medicine is well documented. In the Ayurvedic descriptions, pepper is described as katu (pungent), tikta (bitter), usbnaveerya (potency, leading to storing up of energy, easy digestion, diaphoresis, thirst and fatigue), to subdue vatta (all the biological phenomena controlled by CNS and autonomic nervous system) and kapha (implies the function of heat regulation, and also formation of various preservative fluids like mucus, synovia etc. The main functions of kapha is to provide co-ordination of the body system and regularization of all biological activities). Pepper is described as a drug which increases digestive power, improves appetite, cures cold, cough, dyspnoea, diseases of the throat, intermittent fever, colic, dysentery, worms and piles; also useful in tooth ache, pain in liver and muscle, inflammation, leucoderma and epileptic fits. Black pepper is called maricha or marica in Sanskrit, indicating its property to dispel Read more […]

Historical review of the use of lavender

The classical physicians Lavender has been used as a healing plant and was first mentioned by Dioscorides (c. 40—90 AD) who found what was probably Lavandula stoechas growing on the islands of Stoechades (now known as Hyeres); this was used in Roman communal baths. Dioscorides attributed to the plant some laxative and invigorating properties and advised its use in a tea-like preparation for chest complaints. The author also recounts that Galen (129—99 ad) added lavender to his list of ancient antidotes for poison and bites and thus Nero’s physician used it in anti-poison pills and for uterine disorders. Lavender in wine was taken for snake bites stings, stomach aches, liver, renal and gall disorders, jaundice and dropsy. Pliny differentiated between Lavandula stoechas and Lavandula vera, the latter was apparently used only for diluting expensive perfumes. Pliny the Elder advocated lavender for bereavement as well as promoting menstruation. Abbess Hildegard The Abbess Hildegard (1098—1179) of Bingen near the Rhine in what is now Germany, was the first person in the Middle Ages to clearly distinguish between Lavandula vera and Lavandula spica (): On Palsy one who is tormented should take galangale, with Read more […]

Chamomile: Traditional Use and Therapeutic Indications

Traditional Use Chamomile has been known for centuries and is well established in therapy. In traditional folk medicine it is found in the form of chamomile tea, which is drunk internally in cases of painful gastric and intestinal complaints connected with convulsions such as diarrhea and flatulence, but also with inflammatory gastric and intestinal diseases such as gastritis and enteritis. Externally chamomile is applied in the form of hot compresses to badly healing wounds, such as for a hip bath with abscesses, furuncles, hemorrhoids, and female diseases; as a rinse of the mouth with inflammations of the oral cavity and the cavity of the pharynx; as chamomile steam inhalation for the treatment of acne vulgaris and for the inhalation with nasal catarrhs and bronchitis; and as an additive to baby baths. In Roman countries it is quite common to use chamomile tea even in restaurants or bars and finally even in the form of a concentrated espresso. This is also a good way of fighting against an upset stomach due to a sumptuous meal, plenty of alcohol, or nicotine. In this case it is not easy to draw a line and find out where the limit to luxury is. Clinic and practice Preliminary remark The suitability of the empirical Read more […]

Malva sp. (Mallow)

Distribution and Importance of the Plant Although about 1000 species are designated with the common name of mallow, approximately 30 species belonging to the genus Malva (of the Malvaceae family) are known for their medicinal value, mostly in a traditional sense. The common (blue or high) mallow (Malva sylvestris L.) is a biennial to short-lived perennial with prostrate to semi-erect stems (10-80 cm long) and long-stalked rounded leaves with a heart-shaped base and five to seven broad shallow-toothed lobes. The leaves of M. sylvestris var. incanescens Gris are hairy. The flowers (appearing from May to September) are pale lilac to bright mauve-purple and the seeds are flat button-like nutlets. The plant is found naturally in marginal or waste lands, hedgerows and roadsides and is approximately 1 m high, with stalked, roundish, five- to seven-lobed leaves. Plant parts abound with a mild mucilage. Malva aegyptia (Egyptian mallow) is an annual species, endemic in the Mediterranean countries, 20-50 cm high with purple-blue flowers. Malva cretica (Crecian mallow) is another Mediterranean species, which is an annual, 10-30 cm high with rose-coloured leaves. Malva ambigua Guss (M. sylvestris var. ambigua) is a Read more […]