Thymus Schimperi Research Articles

Antioxidant and Antibacterial Activities of Selected Medicinal Plants from Addis Ababa against MDR-Uropathogenic Bacteria.

This study determined the antioxidant and antibacterial activities of Thymus schimperi (Ts), Rhamnus prinoides (Rp), and Justicia schimperiana (Js) from Addis Ababa against MDR-Uropathogenic bacteria. Accordingly, Thymus schimperi had the highest total phenolic (TPC), flavonoid (TFC) and proanthocyanidin content. In Ts, the GC-MS analyses predicted 14 bioactive compounds. And among these, hexanedioic acid, bis(2-ethylhexyl) ester, thymol, and o-cymen-5-ol were the most predominant compounds, respectively. Six compounds were also predicted in Rp, where hexanedioic acid, bis(2-ethylhexyl) ester, β-D-glucopyranoside, methyl, and desulphosinigrin were the predominant, respectively. Whereas in the Js extract, five bioactive compounds were predicted, with hexanedioic acid, mono (2-ethylhexyl) ester, debrisoquine, and 8,11,14-heptadecatrienoate, methyl ester being predominant compounds, respectively. The extracts' TPC showed a strong negative correlation with the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay (r = -0.999; p = 0.023). In addition, the TFC correlated significantly with the ABTS (2,2'-azino-di-(3-ethylbenzthiazoline sulfonic acid)) assay (r = 0.999; p = 0.032). Thymus schimperi showed the highest antibacterial activity against clinical isolates of Escherichia coli and Klebsiella pneumoniae ESBL at 1000 mg/mL, and Ts had the lowest MIC (4 mg/mL) among evaluated extracts against E. coli (ATCC25922). In conclusion, Ts and Rp possess higher predicted bioactive molecules, including antioxidant and antibacterial activities, which are potentially useful in treating urinary tract infections.

Herbal medicine use and its impact on glycemic control among diabetes patients at governmental hospitals in Debre Berhan, Ethiopia: A cross-sectional study

BackgroundDiabetes mellitus (DM) is a major health concern worldwide. Diabetes patients are increasingly using herbal medicine (HM) without seeking advice from their healthcare providers. However, its impact on glycemic control is not documented in Ethiopia. Thus, this study aimed to assess herbal medicine use and its effect on glycemic control among diabetes patients at governmental hospitals in Debre Berhan town, Ethiopia. MethodsA cross-sectional study involving 430 diabetic patients was conducted at two different hospitals in Debre Berhan town from January 1 to March 30, 2024. Data were gathered using a guided self-administered questionnaire to collect data including glycemic control assessed via hemoglobin A1c (HbA1c) levels. Data was analyzed using SPSS version 25. Logistic regression model was used to assess the predictors of herbal medicine usage, while an independent samples t-test was conducted to compare the mean HbA1c levels between herbal medicine users and non-users among diabetes patients. ResultsOf the 430 participants, 72.6 % were diagnosed with type 2 diabetes. The study revealed 48.1 % (95 % CI: 43.3–53) participants used herbal medicine. Moringa stenopetala (33.5 %), Trigonella foenumgraecum (27.4 %), and Thymus schimperi (17.9 %) were the predominant herbs utilized by diabetic patients. The use of herbal medicine was associated with the patients’ diabetic knowledge (AOR: 1.59; 95 % CI: 1.01–2.49), occupation (AOR: 3.7; 95 % CI: 1.36–10.23), income (AOR: 3.58; 95 % CI: 1.22–10.55), and family history of diabetes (AOR: 1.9; 95 % CI: 1.19–3.18). Glycemic status was not controlled for 86 % of herbal users compared to 66.8 % of non-users. Participants who used herbal medicine had significantly higher mean HbA1c by a mean difference of 0.41 (95%CI: 0.04–0.78). ConclusionsHerbal medicine use was common among diabetes patients in this study. Poor knowledge about diabetes, a family history of diabetes, lower income, and a farming occupation were identified as strong predictors of HM use. Patients who used herbal medicine had significantly higher mean HbA1c levels compared to non-users. Healthcare providers should engage patients in discussions about herbal medicine use, emphasizing the potential risks to glycemic management. Future research should explore specific herbs used, their mechanisms of action, and strategies to integrate herbal medicine safely into diabetes management protocols.

Thymus schimperi Ronniger plant flower extract dye-sensitized solar cells

The demand for energy is greatly increasing due to the world’s population growth and technological advancement. Natural dye-sensitized solar cells are attracting research as an alternative and renewable energy source due to their simple preparation technique, availability, cost effectiveness and environmental friendliness. In the present work, we have successfully fabricated dye-sensitized solar cells (DSSCs) from Thymus schimperi Ronniger plant flowers for the first time. The solvents used for extraction of the flower dye were deionized water and its mixture with ethanol. The T. schimperi Ronniger flower extract dye solutions and sensitized photoanodes were characterized by Fourier transform infrared and ultraviolet–visible techniques. The crystallinity of TiO2 films was analyzed by x-ray diffraction, and the films showed pure anatase phase behavior. The photoelectrochemical solar cell performance parameters, such as short circuit current density, open circuit voltage, fill factor and efficiency, were evaluated from current density–voltage measurements using a Keithley 2450 source meter. DSSCs sensitized with dye solution extracted by a mixture of water and ethanol showed better performance (1.37%) than those sensitized with dye solution extracted by deionized water alone (1.02%).

In silico screening of potential SARS-COV-2 MAIN protease inhibitors from thymus Schimperi

In silico screening of potential SARS-COV-2 MAIN protease inhibitors from thymus Schimperi

Acaricidal Toxicity of Four Essential Oils, Their Predominant Constituents, Their Mixtures against Varroa Mite, and Their Selectivity to Honey Bees (Apis cerana and A. mellifera).

The honey bee (Apis mellifera) faces a significant threat from Varroa destructor, causing the losses of millions of colonies worldwide. While synthetic acaricides are widely used to control Varroa infestations, excessive application has led to resistant strains and poses side effects on the host. Consequently, there is an urgent need for a new acaricide that is both effective and affordable, yet safe to use on bees. One potential source of these acaricides is essential oils (EOs) and their constituents. This study evaluated the acaricidal properties of four essential oils (Eucalyptus globulus, Rosemary officinalis, Trachyspermum ammi (Ethiopian and Indian varieties), their constituents and mixture of constituents against V. destructor through the complete exposure method. Our finding showed that a 1:1 mixture of thymol and carvacrol (4 h-LC50 = 42 μg/mL), thymol (4 h-LC50 = 71 μg/mL), and T. ammi oil (4 h-LC50 = 81-98 μg/mL) were the most toxic test samples against V. destructor. Honey bee behavior and selectivity were also assessed with one additional EO Thymus schimperi, indicating that T. schimperi, T. ammi, and their components were selective and did not affect the learning and memory of bees. In conclusion, the thymol and carvacrol (1:1) mixture was shown to be a promising replacement for synthetic acaricides, being three times more toxic than a commercial acaricide, fluvalinate (4 h-LC50 = 143 μg/mL).

Antioxidant activity and reduction potential of dietary herbs on acrylamide formation in asparagine-glucose reaction model

ABSTRACT Natural ingredients are increasingly being used to prevent the formation of acrylamide during food processing. This study investigated the antioxidant activities of Ocimum basilicum (basil), Lippia adoensis var. adoensis (kesse), Lippia adoensis var. koseret (koseret), Rosmarinus officinalis (rosemary), and Thymus schimperi (tosign) extracts and their acrylamide reduction effect in the asparagine-glucose model system. Folin-Ciocalteu and aluminum chloride methods were used to calculate the total phenolic content (TPC) and total flavonoid content (TFC). Antioxidant activities were determined using 2,2-Diphenyl-1-Picryl-Hydrazyl (DPPH) scavenging and phosphomolybdenum assay methods. Acrylamide contents of the samples were determined by a reversed phase high-performance liquid chromatography (RP-HPLC-DAD) method. Kesse had the highest concentrations of TPC (30.20 ± 1.23 mg gallic acid equivalent per gram of herb extract), TFC (15.87 ± 0.55 mg catechin equivalents per gram), and the strongest DPPH scavenging activity (IC50 = 108 μg/mL). The amount of acrylamide formed during the frying process was decreased by a factor of 26.8% to 65.81% with the addition of dietary herb extracts to the asparagine-glucose reaction model. The amount of acrylamide formed from an asparagine-glucose reaction model containing herb extracts was negatively correlated with the total phenolic and total flavonoid content with, R2 values of 0.920 and 0.930. This study suggests a potential application of these dietary herb extracts as a natural antioxidant for lowering acrylamide formation during the Maillard reaction in fried food products.

Ethnobotany of wild edible plants in Soro District of Hadiya Zone, southern Ethiopia

BackgroundDespite their paramount importance all over the globe in supporting food security, information about wild edible plants is generally patchy. In this study, we investigated the wild edible plants used by the local people in the Soro District of Hadiya Zone, southern Ethiopia. The main purpose of the study was to document and analyze the indigenous and local knowledge of the people on their abundance, diversity, use and management.Methods and materialsPurposive sampling and systematic random sampling were used to identify informants who can give information about the wild edible plants of the area. Data were collected by interviewing 26 purposively sampled key informants and 128 systematically randomly sampled general informants using semi-structured interviews. Guided observations and 13 focus group discussions (FGDs) consisting of 5–12 participants/discussants at each FGD session were also undertaken. Statistical analyses (mainly descriptive statistics approaches) and common analytical tools of ethnobotany including informant consensus, informant consensus factor, preference ranking, direct matrix ranking, paired comparison and index of fidelity level were applied to the data sets.ResultsA total of 64 wild edible plant species belonging to 52 genera and 39 families were recorded. All of these species are indigenous, 16 are new additions to the database and seven of them, including Urtica simensis and Thymus schimperi, are endemic to Ethiopia. In about 82.81% of the species, the edible plant part is also used in the Ethiopian traditional herbal medicine. It is striking to see that almost all wild edible plants recorded from the study area are nutraceutical plant species, serving multiple roles as food and therapeutic sources for the local people. We recorded five growth habits of 34.38% trees, 32.81% herbs, 25% shrubs, 6.25% climbers, and 1.56% liana. We found the Flacourtiaceae, Solanaceae, and Moraceae to be families that represented more species (4 each), followed by Acanthaceae, Apocynaceae, Amaranthaceae, and Asteraceae, which accounted for 3 species each. Fruits (53.13%) and leaves (31.25%) were consumed in more proportions than other edible parts (15.63%); mostly the ripe, raw fruit is eaten upon simple processing, followed by leaves eaten after boiling, roasting and cooking.ConclusionThe frequency and intensity of consumption of these plants varied significantly (P < 0.05) with gender differences, key and general informants, and people’s religious backgrounds. We postulate that priority setting for in situ and ex situ conservation of multipurpose wild edible plants in human-inhabited landscapes is essential to warrant sustainable use and conservation of the species as well as the use of new modes of application and valorization.

Diet composition and diurnal activity patterns of gelada baboon (Theropithecus gelada)

AbstractGelada baboons (Theropithecus gelada) are the only surviving species of the genus Theropithecus and endemic to the highlands of Ethiopia. The present study deals with feeding ecology and diurnal activity patterns of gelada (T. gelada) in Wof‐Washa Forest, central Ethiopia. It was conducted from September 2016 to August 2017. Focal sampling technique for 10 min observation was employed to study the feeding ecology. Type of plant species consumed and parts eaten by gelada were recorded using binoculars during dry and wet seasons. On the other hand, data on diurnal activity patterns were collected using scan sampling technique. The activity patterns of bands under study were quantified by scanning at every 15‐min interval from 06:00 to 18:00 h. A total of 11 plant species that belong to 10 families were foraged by gelada during the wet and dry seasons. Grass was the main food source for geladas that contributed about 81% and 68% of their diet during the wet and dry seasons, respectively, while Thymus schimperi was the least consumed plant species during both wet (0.5%) and dry (1%) seasons. Grass blades were the most preferable food items by almost all age and sex categories. Daily activities of gelada were mainly dominated by feeding during both seasons. Geladas spent 58% of their time on foraging activity during the wet season and 67.2% of their time spent during the dry season. Geladas mainly depend on grasses for their diet in the study area. Therefore, to implement successful management and conservation of the species, the area needs to be properly protected.

Yolk Fatty Acid Content, Lipid Health Indices, and Oxidative Stability in Eggs of Slow-Growing Sasso Chickens Fed on Flaxseed Supplemented with Plant Polyphenol Extracts.

Previous attempts to increase the level of flaxseed in hens' diet for the production of n-3 polyunsaturated fatty acids (n-3 PUFAs)-enriched eggs have been commonly associated with undesirable effects on production efficiency, lipid health indices, and oxidative stability of eggs, requiring adequate research attention. This study investigated the effects of feeding a moderate level of flaxseed (FS) and plant polyphenol extracts (PPEs) on fatty acid content, oxidative stability, and lipid health indices in eggs of slow-growing Sasso T451A laying hens. One hundred and five hens were assigned to five groups (seven replicates of three) and fed on FS (75 g flaxseed and no antioxidants), VE8 (75 g flaxseed and 800 mg vitamin E), TS8 (75 g flaxseed and 800 mg Thymus schimperi), DA8 (75 g flaxseed and 800 mg Dodonaea angustifolia), and CD8 (75 g flaxseed and 800 mg Curcuma domestica) extract per kg diets. The egg yolk content of eicosapentaenoic acid (EPA, C20:5 n-3) in the DA8, TS8, and CD8 diets and docosahexaenoic acid (DHA, C22:6 n-3) in TS8 and CD8 diets significantly (p < 0.05) increased compared with the FS diet. The FS diet significantly increased the malondialdehyde (MDA) content in egg yolks, whereas the TS8 diet decreased it by 67% (p < 0.05). Little difference was observed in yolk fatty acid content between cooked and raw eggs. Production of n-3 PUFA-enriched eggs with favorable lipid health indices was possible through inclusion of PPEs extracted from local plant species grown in Ethiopia and a moderate dose of flaxseed in the diet of laying hens.

In silico Screening of Potential SARS-CoV-2 Main Protease Inhibitors from Thymus schimperi.

COVID-19 is still instigating significant social and economic chaos worldwide; however, there is no approved antiviral drug yet. Here, we used in silico analysis to screen potential SARS-CoV-2 main protease (Mpro) inhibitors extracted from the essential oil of Thymus schimperi which could contribute to the discovery of potent anti-SARS-CoV-2 phytochemicals. The absorption, distribution, metabolism, excretion, and toxicity (ADMET) profiles of compounds were determined through SwissADME and ProToxII servers. AutoDock tools were used for molecular docking analysis studies, while Chimera, DS studio, and LigPlot were used for post-docking studies. Molecular dynamic simulations were performed for 200 ns under constant pressure. All compounds exhibited a bioavailability score of ≥0.55 entailing that at least 55% of the drugs can be absorbed unchanged. Only five (9%), nine (16%) and two (3.6%) of the compounds showed active hepatotoxicity, carcinogenicity, and immunotoxicity, respectively. Except for flourazophore P, which showed a little mutagenicity, all other compounds did not show mutagenic properties. On the other hand, only pinene beta was found to have a little cytotoxicity. Five compounds demonstrated effective binding to the catalytic dyad of the SARS-CoV-2 Mpro substrate binding pocket, while two of them (geranylisobutanoate and 3-octane) are found to be the best hits that formed hydrogen bonds with Glu166 and Ser144 of SARS-CoV-2 Mpro. Based on our in silico analysis, top hits from Thymus schimperi may serve as potential anti-SARS-CoV-2 compounds. Further in vitro and in vivo studies are recommended to characterize these compounds for clinical applications.

In Vitro Antioxidant Activities of Plant Polyphenol Extracts and Their Combined Effect with Flaxseed on Raw and Cooked Breast Muscle Fatty Acid Content, Lipid Health Indices and Oxidative Stability in Slow-Growing Sasso Chickens.

Adding flaxseed was found to decrease oxidative stability in feed and increase the antioxidant needs of chicken. This has also been associated with a decrease in the nutritional value and oxidative stability of meat if sufficient dietary antioxidants are not included. Furthermore, dietary flaxseed has been explored in fast-growing chickens as such studies are limited with slow-growing chickens. Thus, this study aimed to evaluate the effects of feeding plant polyphenol extracts as an antioxidant alongside flaxseed on fatty acid content, oxidative stability, and lipid health indices in breast muscle of slow-growing Sasso T451A dual-purpose chicken. A total of 126 chickens assigned to six groups (seven replicates of three) were fed on NC (control and no antioxidants), FS (75 g flaxseed and no antioxidants), VE8 (75 g flaxseed and 800 mg vitamin E), TS8 (75 g flaxseed and 800 mg Thymus schimperi), DA8 (75 g flaxseed and 800 mg Dodonaea angustifolia) and CD8 (75 g flaxseed and 800 mg Curcuma domestica) extract per kg diet. Feeding on CD8 and VE8 in raw and TS8, CD8 and VE8 diets in cooked breast muscle increased (p < 0.05) the C22:6n − 3 (DHA) and C20:5n − 3 (EPA) contents compared to the FS diet. Feeding FS increased (p < 0.05) the malondialdehyde (MDA) content in breast muscle, whereas TS8 in cooked and raw and CD8 and DA8 diets in raw breast muscle decreased it (p < 0.05). No added benefit was observed in feeding VE8 over plant extracts in terms of improving fatty acid composition and lipid health indices and reducing lipid oxidation in breast meat.

Phytochemical composition of essential oils from aromatic plants inherited with bioherbicidal activity in arabica coffee production system of Ethiopia

Essential (EOs) can be considered as an alternative tool to control weeds, as they are eco-friendly and safe bioherbicides. Based on their herbicidal efficacy against coffee weeds in the prescreening under in-vitro , lath-house and field experimentations, five aromatic plants namely, Cymbopogon citratus , C. martinii , C. winterianus , Eucalyptus citriodora and Thymus schimperi were selected to identify their chemical composition using Gas Chromatography-Mass Spectrometry. The chromatographic analysis revealed the presence of 45 compounds in C. citratus oil dominated with citral (84.86%) from the subclasses of trans-Citral and cis-Citral. Thirty-three compounds were fractionated and identified in C. martinii oil containing geraniol (55.27%), trans-Geranyl acetate (16.82%), (6R,7R)-Bisabolone (7.23%) and trans-.beta.-Ocimene (6.18%) as the main inherited components. The EO from C. winterianus contained 47 compounds with citronellal (31.31%), geraniol (21.24%), citronellol (12.06%) and elemol (6.68%) as the major component. Similarly, a total of 52 compounds were identified from the EO of E. citriodora containing two major compounds namely, citronellal (76.93%) and citronellol (15.24%). The EO from T. schimperi were composed of 32 compounds with carvacrol (72.55%) and thymol (9.12%) as the main constituents. The present finding indicated that herbicidal activities of the EOs might be attributed to their fingerprint components such as citral (3,7-dimethylocta-2,6-dienal), geraniol (2E)-3,7-dimethylocta-2,6-dien-1-ol), citronellal (3,7-dimethyloct-6-enal), citronellol (3,7-Dimethyloct-6-en-1-ol), carvacrol (2-methyl-5-propan-2-ylphenol) and thymol (5-methyl-2-propan-2-ylphenol). Therefore, these bioactive agents have the potential to be used as herbicides to manage weed species in coffee farms for the future. • Cymbopogon species, Eucalyptus citrodora and Thymus species had bioherbicidal activities. • Citral, citronellal, citronellol, geraniol, carvacrol and thymol are major compounds found in EOs of the tested plants. • The major constituents in the EOs of the investigated plants are enriched in monoterpenes. • The herbicidal activities of the EOs might be attributed to their fingerprint components.

In vitro antioxidant activity of Lippia adoensis Var. Koseret, Thymus schimperi Ronniger and Rosmarinus officinalis Leaf extracts and their effects on oxidative stability of ground raw beef meat during refrigeration storage

Rosmarinus officinalis,Thymus schimperi Ronniger, and Lippia adoensis var. koseret, locally known as Rosemary, Tosign, and Koseret respectively are widely used dietary herbs in Ethiopia. In this study, the antioxidant activity and effect of Rosemary, Tosign, and Koseretethanol (80% v/v) extract on lipid oxidation of ground beef during storage were studied. Folin-Ciocalteu and aluminium chloride were used to determine total phenolic content (TPC) and total flavonoid content (TFC), respectively. Antioxidant activities of herbs were evaluated using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging, ferric reducing power and iron chelating activities. The peroxide and thiobarbituric acid reactive substances assays were used to evaluate the ability of the extracts to prevent lipid peroxidation in ground beef stored at 4°C. Tosign extract had highest TPC (70.93±1.53 mg GAE/g) and TFC (16.94±0.12 mg CE/g). Also, Tosign had the strongest effect of DPPH scavenging (IC50 = 33.35±1.56µg/mL) and ferric reducing power (IC50 = 175.71±1.03 µg/mL). But the strongest iron-chelating activity was observed in Rosemary extract (IC50 = 160.24±2.55 µg/mL). Minimum peroxide value (0.185±0.09 milli equivalent peroxide/kg of beef) and the highest thiobarbituric acid reactive substances (80.20±20%) were recorded for ground beef treated with Rosemary at the end of storage days. In conclusion, these herbs are very effective antioxidants comparable to butylated hydroxytoluene. Thus, they could be a good substitution to synthetic antioxidants used in food preservation.

Evaluation of Essential Oils Against Potato Late Blight (Phytophthora infestans (Mont.) de Bary) at Holleta, Ethiopia

This study was conducted to evaluate essential oils from Croton macrostachyus Hochst. ex Delile, Eucalyptus globulus Labill., Allium sativum L., Cymbopogon citratus (DC.) Stapf, Cymbopogon martini (Roxb.) W.Watson, Rosmarinus officinalis L. and Thymus schimperi Ronniger using four concentrations (l mL, 2 mL, 3 mL, 4 mL) and three sprays against potato (Solanum tuberosum L.) late blight disease. Two improved potato varieties were planted using randomized complete block design with factorial combinations in three replications. Analysis of disease incidence means at 53 and 60 days after planting showed highly significant differences between varieties and among sources of essential oils. Furthermore, the combined effect of essential oils and potato varieties on disease severity showed significant differences. Disease severity was maintained from 25% to 48% (Jalene); 13% to 30% (Gudene) with essential oils while it was maintained between 92% and 95% (Jalene); 37% to 38% (Gudene) for control plants. The lowest disease percentage of disease severity was obtained on plants treated with A. sativum for Jalene variety while on plants sprayed with C. macrostachyus, E. globulus and T. schimperi for Gudene variety. The lowest disease progress rate 0.198/day and 0.162/day as well as values of area under disease progress curve 228% days and 93% days were obtained for varieties Jalene and Gudene, respectively. Maximum reduction in mean disease severity was exhibited by garlic for varieties Jalene (28.3%) and Gudene (16.3%), as compared to the control (93.3% for Jalene and 37.5% for Gudene). Therefore, results indicated the potentials of essential oils to minimize effects of potato late blight disease. Communities involved in potato production could use the current results as base line information to find alternative management options for late blight disease which has no effect on human health and environment. However, further investigation is required on essential oils affordability and availability to farmers across different locations.

The Developmental Toxicity of Thymus schimperi Essential Oil in Rat Embryos and Fetuses.

Background In Ethiopian traditional medicine, the aerial parts of Thymus schimperi are widely used to treat diseases such as gonorrhea, cough, liver disease, kidney disease, hypertension, stomach pain, and fungal skin infections. In addition, they have been used as vegetables to flavor a broad variety of food products. However, there is an insufficient investigation of the toxic effect of Thymus schimperi essential oil. The aim of this study was, therefore, to evaluate the developmental toxicity of the essential oil of Thymus schimperi leaves on developing rat embryos and fetuses. Methods Essential oil of the aerial parts of Thymus schimperi was extracted by hydrodistillation. Pregnant Wistar albino rats were randomly divided into five groups. The doses 65 mg/kg, 130 mg/kg, and 260 mg/kg of the essential of Thymus schimperi were administered by force feeding to the III–V groups, respectively. Groups I and II were negative and ad libitum control groups. The embryos and fetuses were revealed on days 12 and 20 of gestations, respectively. The embryos were examined for developmental delays or growth retardation. Gross external, skeletal, and visceral anomalies in the fetuses were examined. Results In this study, the developmental scores of the number of implantation sites, crown-rump length, the number of somites, and morphological scores were significantly lower while the score of fetal resorptions was increased in a 12-day-old rat embryos treated with 260 mg/kg of the Thymus schimperi essential oil. There was also a significant delay in the development of the otic system, olfactory system, and a reduction in the number of branchial bars in 12-day-old embryos treated with 130 mg/kg and 260 mg/kg of the essential oil. However, external morphological examinations of rat fetuses revealed no detectable structural abnormalities. The fetal skull, vertebrae, hyoid, forelimb, and hindlimb ossification centers did not differ significantly across all the groups. Furthermore, there were no skeletal or soft-tissue malformations as a result of the essential oil treatment. Although the difference was not statistically significant, fetuses of the high-dose treatment group had a reduced number of ossification centers in the caudal vertebrae and hind limp phalanges. Conclusion The essential oil of Thymus schimperi at high doses has a detrimental effect on the development of rat embryos and fetuses. Its developmental toxicity is evidenced by significant delays in fetal and embryonic development, a decrease in the number of implantation sites, and an increase in fetal resorption. Furthermore, administration of the essential oil in higher doses resulted in a significant decrease in placenta weight and litter weight. In addition, the present study provided evidence that using the Thymus schimperi essential oil in a high dose could affect the developing embryo and fetus. Thus, it is recommended to discourage the use of Thymus schimperi essential oil in high doses.

Effects of essential oils on potato tuber sprouting at room temperature storage in Ethiopia

This study was conducted with the objective of finding alternative management options for potato tuber sprouting during storage. Essential oils from Croton macrostachyus, Eucalyptus globulus, Allium sativum, Cymbopogon citratus, Cymbopogon martini, Rosmarinus officinalis and Thymus schimperi were applied in completely randomized design using two quantities (1 and 2 ml) and three frequencies (1, 2, 3). Essential oils from Cymbopogon citratus and Thymus schimperi showed the lowest percentage of weight loss relative to control tubers for varieties Gudene (8.07%) and Jalene (13.34%), respectively. Essential oils were applied in the form of vapour inside wooden box for 24 h without direct contact with tubers. For both varieties, the potato tuber weight loss found to be minimized using 2 ml essential oils. Similarly, lowest percentage of weight loss at one, two and three applications were found for variety Jalene from Cymbopogon martini, Eucalyptus globulus and Croton macrostachyus, respectively. On the other hand, lowest percentage of weight loss was maintained using Eucalyptus globulus for variety Gudene. The number and length of sprouts did not vary with quantities. Therefore, for variety Gudene, lower number of sprouts relative to control tuber (3 sprouts/tuber) was found on potato tuber treated with essential oils from Cymbopogon martini and Thymus schimperi (2.7 sprouts/tuber) whereas for variety Jalene, lower number of sprouts relative to control tuber (8.7 sprouts/tubers) was found on potato tubers treated with essential oils from Allium sativum and Rosmarinus officinalis (5.7 sprouts/tuber). The length of the longest sprouts on control tubers was 11.7 mm and 20 mm for varieties Gudene and Jalene, respectively. Longest and shortest length of sprout was found on potato tubers treated with Eucalyptus globulus and Rosmarinus officinalis, respectively, for both varieties. Therefore, essential oils used in the current study are promising alternatives to control potato sprouting during storage. However, seedlings of these species and other potential species must be made available to farmers with training on how to make extracts and apply them.

Determinations of Physicochemical Properties, Proximate Compositions, and Characterization of Chemical Constituents of Thymus schimperi Essential oil

Thymus schimperi is endemic to Ethiopia and it is well-known in central, eastern and northern parts of the country. Investigation has been carried out to determine the physicochemical properties, and to analyze the proximate values of the leaves and chemical composition of T. schimperi leaf essential oils grown at Ankober district, Ethiopia. To get the essential oil, the shade dried ground leaves of T. schimperi were subjected to hydrodistillation for 3 h using a Clevenger-type apparatus. The percent yield of the leaf essential oil (1.85 %), physicochemical properties of the oil such as refractive index (1.484), relative density (0.941), optical rotation (-1.8o), solubility (insoluble in water and soluble in ethanol), color (yellowish) and odor (aromatic) were determined. Analysis of the proximate values of T. schimperi leaves such as total ash, water soluble ash; acid insoluble ash, moisture content and pH were found to be 9.14, 3.34, 2.52, 12.4 and 6.17, respectively. The essential oil of T. schimperi was analyzed using GC-MS and a total of thirteen volatile components, representing 98.82 % of the total composition, were identified. The main components of the essential oils are thymol (71.02 %), p-myrcene (15.25 %), ϒ-terpinene (9.02 %), Phenylethanone (1.33 %) and α-phellandrene (1.062 %).

Acaricidal activity of essential oil-derived components from Thymus schimperi Ronninger against Varroa destructor Anderson and Trueman

The ectoparasitic mite Varroa destructor has become a major worldwide pest of the honey bees (Apis mellifera L). Intensive use of chemical acaricides has led to the development of acaricide resistance in mites, thereby reducing the efficacy of acaricides and causing contamination of hive products. Thus, natural products such as essential oils can become an important alternative to synthetic chemicals in controlling Varroa mites. In this study, essential oil from Thymus schimperi grown in the Ethiopian highland was investigated for its chemical composition and toxicity against Varroa mites through complete exposure tests. Hydrodistillation of T. schimperi leaves yielded a pale yellow essential oil (0.8% v/w) with a strong and pleasant odor. Analyzed by GC-MS, 29 compounds, comprising 96.67% of the oil, were identified. Carvacrol (34.84%), thymol (23.03%), and p-cymene (14.20%) were found to be the main constituents. In the toxicity assay, T. schimperi essential oil showed high acaricidal activity against Varroa mites, with a 4 h-LC50 value of 109.16 µg/ml (5.46 mg oil/l air volume). Among the main constituents, thymol and carvacrol induced high toxicity to Varroa mites, with 4 h-LC50 values of 70.71 µg/ml (3.54 mg thymol/l air volume) and 106.10 µg/ml (5.31 mg carvacrol/l air volume), respectively. However, p-cymene was less effective in toxicity testing (4 h-LC50 > 5000 µg/ml). The results show for the first time that the essential oil of Thymus schimperi and its two main constituents, thymol and carvacrol, are highly acaricidal and can be used to control Varroa mite infestations.

Biogenic Synthesis of Magnetite Nanoparticles Using Leaf Extract of Thymus schimperi and Their Application for Monocomponent Removal of Chromium and Mercury Ions from Aqueous Solution

Currently, plant templated synthesis of magnetite iron oxide nanoparticles (Fe3O4 NPs) was emerged for multifunctional purposes. In this study, the leaf extract of the plant Thymus schimperi was utilized to synthesize Fe3O4 NPs. The synthesized NPs were characterized by using technical tools such as X‐ray diffraction (XRD) spectroscopy, Fourier transform infrared (FT‐IR) spectroscopy, scanning electron microscopy‐energy dispersive X‐ray (SEM‐EDX) analysis, and ultraviolet‐visible (UV‐Vis) spectroscopy, and thermal analysis (TGA‐DTA). The XRD result corroborated the presence of desired phase formation having pure cubic face centered phase structure with average crystallite particle size ranging from 20 nm to 30 nm. SEM micrographs confirmed microstructural homogeneities and remarkably different morphology of Fe3O4 NPs. Mercury (II) and chromium (VI) removal efficiencies of Fe3O4 NPs were found to be 90% and 86% from aqueous solution at initial concentration of 20 mg/L, respectively. Various factors which affect the metal ion removal efficiency such as metal ion initial concentrations, pH, contact time, and adsorbent dosage were also studied. The optimum pH and contact time for chromium ion adsorption were pH 5 and 60 min and that of mercury were observed to be pH 7 and 90 min, respectively. The Langmuir isotherm was best fitted for sorption of Hg(II) ion, and the Freundlich isotherm was best fitted with sorption of Cr(VI) ion onto the surface of Fe3O4 NPs. The mechanism of adsorption of both Hg(II) and Cr(VI) ions was obeyed pseudo 2nd order kinetics. The recorded percent removal efficiencies revealed that these Fe3O4 NPs synthesized through leaf extract of the plant called Thymus schimperi have demonstrated excellent potentiality in the remediation of heavy metal ions. The synthesized Fe3O4 NPs were regenerated (reused) for adsorptive removal of Hg(II) and Cr(VI) for five consecutive cycles without significant loss of removal efficiency. Fe3O4 NPs were reused with only 4.17% loss of removal efficiency against Hg(II) and only 3% loss of removal efficiency against Cr(VI) metal ions.

Effects of Inclusion of Different Levels of Ethiopian Thyme (&amp;lt;i&amp;gt;Thymus schimperi&amp;lt;/i&amp;gt; Ronniger) as Natural Additive on Chemical Composition and &amp;lt;i&amp;gt;In Sacco&amp;lt;/i&amp;gt; Dry Matter Degradability of Total Mixed Ration and Feed Ingredients

This study evaluated the effects of the inclusion of Ethiopian thyme (Thymus schimperi Ronninger) to natural pasture hay (NPH), noug seed cake (NSC), wheat bran (WB) and total mixed ration (TMR) on the chemical composition and in Sacco dry matter (DM) degradability of the feeds. The Thyme plant used for the study was collected from Dinsho and Tarmaber districts in the highlands of Ethiopia. Samples of the TMR and NPH, WB and NSC with or without thyme were divided into two parts and ground to pass through 1 mm screen for chemical analysis and 2 mm screen for in sacco DM degradability. The TMR contained 50% NPH, 32.5% WB, 14% NSC, 3% molasses and 0.5% common salt. The feed ingredients (NPH, WB and NSC) and the TMR were incubated without thyme or with thyme substituting the diet at 8%, 16% and 24% levels of treatments. The chemical composition of all the feeds differed significantly (P In sacco rumen dry matter degradability of NPH, WB, NSC and TMR was increased (P in sacco DM degradability of NPH at all incubation hours was higher (P Thymus schimperi plant up to a level of 24% DM in feed can reasonably stimulate the growth and activity of the certain rumen microbes that promoted an improvement in ruminal DM degradability of the diet with the thyme inclusion.