Additive and synergistic effects of Bacillus spp. isolates and essential oils on the control of phytopathogenic and saprophytic fungi from medicinal plants and marigold seeds

Contamination of plants and seeds with microorganisms is one of the main problems in the production and distribution of various agricultural products, as well as raw herbal material for the preparation of herbal remedies. In targeting microbial contamination, among other bacteria, Bacillus species showed a significant capacity for biocontrol. The antifungal activity of 14 isolates of Bacillus spp. against 15 fungal isolates from medicinal plants was examined utilizing a dual plate assay. The strongest and broadest antagonistic activity against all fungi tested was exhibited by isolates SS-12.6 and SS-13.1 (from a 43% to 74% reduction in fungal growth), while isolates SS-39.1 and SS-39.3 were effective against the fewest fungus species and also had the weakest antifungal activity. The effect of a crude lipopeptide extract (CLE) of Bacillus sp. SS-12.6 was similar to that achieved by a dual culture with isolate SS-12.6, confirming that the antagonism was the result of the antifungal activities of lipopeptides. In addition, essential oils of thyme (0.55 mg/mL) and savory (0.32 mg/mL) in various combinations with the CLE of SS-12.6 were tested for antifungal activity, and additive and synergistic effects for some of the fungi were obtained. When testing the effect of CLE, oils (0.40 mg/mL for thyme oil and 0.21 mg/mL for savory oil) and combinations in situ on marigold seeds, a reduction of total fungal infection without an adverse effect on germination was accomplished by 6-h treatments with CLE of SS-12.6 (85% reduction of fungal infection and 63% germination), supernatant from liquid culture of SS-12.6 (more than 90% reduction of fungal infection with 69% seed germination) and combinations of CLE and savory oil (77% reduction of fungal infection and 62% seed germination) and CLE with thyme and savory oils (about 75% reduction of fungal infection with 69% seed germination).     

Investigations on influencing plant-associated bacteria in tissue cultures of black locust (<Emphasis Type="Italic">Robinia pseudoacacia</Emphasis> L.)

During tissue culture of black locust (Robinia pseudoacacia L.), serious problems with plant-associated bacteria led to a reduction of propagation potential in several clones. Four dominant strains of plant-associated bacteria could be isolated and were assigned to the genera Acidovorax, Dyella, Microbacterium and Sphingomonas. Out of five essential oils tested, thyme and lemongrass oil at a concentration of 0.03% each and 0.015% of both oils in combination clearly inhibited the growth of these bacteria strains on bacteriologic medium. There were no significant differences in total bacterial population density when penicillin, thyme and lemongrass oil or thyme plus lemongrass oil were added to the plant propagation media. The use of lemongrass oil changed the proportion of dominant bacterial strains.     

Advanced fibre optical scanning in thin-layer chromatography for drug identification

A reliable and sensitive method was developed for determination of thymol in human plasma by automated headspace solid-phase microextraction (SPME). After enzymatic cleavage of thymol sulfate thymol was extracted by a 65 microm polydimethylsiloxane-divinylbenzene crimped fiber (Supelco) after addition of sodium chloride and phosphoric acid (85%). Desorption of the fiber was performed in the injection port of a gas chromatograph at 220 degrees C (HP 5890; 50 m x 0.2 mm I.D., 0.2 microm HP Innowax capillary column; flame ionization detection). Fibers were used repeatedly up to 40 analysis. The recovery was 5% after 35 min of extraction. The calibration curve was linear in the range of 8.1-203.5 ng ml(-1) with a limit of quantitation (LOQ) of 8.1 ng ml(-1). The within-day and between-day precision and accuracy were < or = 20% at the LOQ and <15% at higher concentrations according to international guidelines for validation of bioanalytical methods. After administration of a thymol-containing herbal extract only thymol sulfate, no free thymol, could be detected in human plasma, thus analysis of thymol was after enzymatic cleavage of thymol sulfate. It is concluded that the newly developed automated method can be used in clinical trials on bioavailability and pharmacokinetics of thymol-containing herbal medicinal products.     

Beneficial effects of thyme oil on age-related changes in the phospholipid C20 and C22 polyunsaturated fatty acid composition of various rat tissues

The aim of this study was to determine any age-related changes in phospholipid polyunsaturated fatty acid composition, in particular C₂₀ and C₂₂ fatty acids in rat liver, brain, kidney and heart, and to assess and compare the effects of dietary supplementation (42.5 mg/kg body weight/day) of the natural antioxidant thyme oil and its major component thymol throughout the rat life span. The fatty acid composition in the various tissues from young (7 months) and aged (28 months) rats was determined and compared. Livers from aged control, thyme oil and thymol treated rats exhibited an increase in 22:6(n–3). In contrast, 22:6(n–3) content of brain, kidney and heart declined in aged rats in all three dietary groups. However, aged rats treated with thyme oil and thymol displayed significantly higher levels of 22:6(n–3) than the respective age-matched controls. Tissue compositions of 20:4(n–6) were found to be significantly lower in the liver and kidney from aged control rats but not those fed either thyme oil or thymol. In aged rats, the composition of 20:4(n–6) in all tissues was highest in rats fed either thyme oil or thymol. These results show that dietary supplementation with thyme oil tended to maintain higher PUFA levels in all tissues studied. The majority of protection provided by thyme oil was by virtue of its thymol component, which comprises 49% of the whole oil. Thymol administered alone did not provide significantly higher protection than the whole oil, suggesting that other components within thyme oil are also contributing antioxidant activity.     

Ameliorative effects of thyme and calendula extracts alone or in combination against aflatoxins-induced oxidative stress and genotoxicity in rat liver

The aims of the current work were to evaluate the hepatoprotective effect of calendula flowers and/or thyme leave extracts on aflatoxins (AFs)-induced oxidative stress, genotoxicity and alteration of p53 bax and bcl2 gene expressions. Eighty male Sprague–Dawley rats were divided into eight equal groups including: the control group, the group fed AFs-contaminated diet (2.5 mg/kg diet) for 5 weeks, the groups treated orally with thyme and/or calendula extract (0.5 g/kg b.w) for 6 weeks and the groups pretreated orally with thyme and/or calendula extract 1 week before and during AFs treatment for further 5 weeks. Blood, liver and bone marrow samples were collected for biochemical analysis, gene expression, DNA fragmentation and micronucleus assay. The results showed that AFs induced significant alterations in oxidative stress markers, increased serum AFP and inflammatory cytokine, percentage of DNA fragmentation, the expression of pro-apoptotic gene p53 and bax accompanied with a decrease in the expression of bcl2. Animals treated with the extracts 1 week before AFs treatment showed a significant decrease in oxidative damage markers, micronucleated cells, DNA fragmentation and modulation of the expression of pro-apoptotic genes. These results suggested that both calendula and thyme extracts had anti-genotoxic effects due to their higher content of total phenolic compounds.     

Monoterpenoids and their glycosides from the leaf of thyme

From the polar portion of the methanol extract of thyme (leaf of Thymus vulgaris; Labiatae), which has been used as an important stomachic, carminative, a component of prepared cough tea, and a spice, seven monoterpenoid glycosides were isolated together with two known monoterpenoids and three known monoterpenoid glucosides. Structures of the seven monoterpenoid glycosides were determined by spectral analysis.     

Phytochemical,Ecological and Antioxidant Evaluation of Wild Sicilian Thyme: Thymbra capitata (L.) Cav.

In a broad survey conducted throughout the Sicily region, 45 different sites were identified where thyme grows wild. All the biotypes collected were classified as Thymbra capitata (L.) Cav. (syn. Thymus capitatus (L.) Hoffmanns . & Link ). Cluster analysis based on the main morphological characteristics of the plant led to the division of the biotypes into 3 major groups. All samples were analyzed for their secondary phytochemical metabolites identified in the extracts and the essential oils. LC‐UV‐DAD/ESI‐MS and GC‐FID/GC‐MS have been applied to characterize the extracts and the essential oils, respectively. In the extracts, 15 flavonoid derivatives with taxifolin‐di‐O‐glucoside and thymusin as main components, and 2 organic acids, with a large predominance of rosmarinic acid, were identified. On the whole 37 compounds were fully characterized in the essential oils, carvacrol was identified as the main component with an average value of 73.93%. The total phenol content and the antioxidant activity of all phytochemical complexes were determined with the Folin–Ciocalteu (FC) assay, the UV radiation‐induced peroxidation in liposomal membranes (UV‐IP test), and the scavenging activity of superoxide radical ().     

百里香提取物抑菌特性的研究

以百里香水和酒精提取物及百里香芳香油作为抑菌剂进行抑菌试验 ,结果表明 ,所用抑菌物对供试菌金黄色葡萄球菌 (Staphalococcusaureus)、枯草芽孢杆菌 (Bacillussubtilis)和大肠杆菌 (Escherichiacoli)均有不同程度的抑制作用 ,可望将其用于食品工业作为防腐和抑菌剂。     

Effects of mint,thyme, and curcumin extract nanoformulations on the sperm quality,apoptosis, chromatin decondensation,enzyme activity,and oxidative status of cryopreserved goat semen

Goat semen cryopreservation is a challenging process as it results in reduced motility, vitality, and fertility of spermatozoa after freezing. In this study, we evaluated the effects of different herbal extract nanoformulations (NFs) [mint (MENFs), thyme (TENFs), and curcumin (CENFs)], supplemented at either 50 or 100 μg into Tris-extender on the cryopreserved goat semen quality. The hydrothermal squeezing method was used for the preparation of the NFs extracts. The morphological evaluation of the NFs extracts was conducted by transmission electron microscopy. All NFs supplements improved (p < 0.05) the progressive motility, vitality, and plasma membrane integrity of sperm compared with the control extender after equilibration (5 °C for 2 h) and thawing (37 °C for 30 s), but had no effect on sperm abnormality and acrosome integrity. All NFs supplements decreased (p < 0.05) the apoptosis, malondialdehyde level, and chromatin decondensation of sperm cells, while increased (p < 0.05) the total antioxidant capacity and catalase activity in the frozen/thawed extender. Particularly, CENFs at a level of 100 μg showed improvement of sperm parameters and antioxidant status during cryopreservation of goat semen more than TENFs and MENFs. The CENFs improved the quality of goat spermatozoa in post-thawed semen in terms of preventing cryodamage and promoting the cryotolerance of spermatozoa when compared with TENFs and MENFs. Therefore, supplementation of Tris-extender with CENFs could enhance goat semen processing during cryopreservation.