Antioxidant and Anticancer Activities of Anethum graveolens L., Citrus limon (L.) Osbeck and Zingiber officinale Roscoe Essential Oils

Since synthetic chemotherapeutic drugs produce a certain degree of drug resistance and due to their common side effects, such as damage to hematopoietic cells and hair loss, it is necessary to use herbal medicine as a substrate to develop new anticancer drugs. The ingredients of three essential oils (EO) were identified using gas chromatography–mass spectrometry (GC-MS) analysis. Their anticancer activities have been investigated on four human breast cancer cell lines, including MCF-7, MDA-MB-175, MDA-MB-231, and MDA-MB-468. In addition, their antioxidant activity was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The three plants were investigated for identifications of the ingredients of their EOs, and major ingredients were identified in each plant as alpha-phellandrene (26.75 %) in Anethum graveolens L., limonene (61.83 %) in Citrus limon (L.) Osbeck, and zingiberene (30.28 %) in Zingiber officinale Roscoe. Among the EOs, C. limon was significantly more effective than others; its half-maximal inhibitory concentration (IC50) on MCF-7 was obtained at 201 µg.mL-1. Furthermore, Z. officinale EO showed a higher antioxidant activities in comparison to the two other EOs. Considering the antioxidant and anticancer effects of the EOs, they could be further investigated as a possible complementary medicine in cancer.

Herbal medicine used for the treatment of diarrhea and cough in Kampala city, Uganda

Background Globally, diarrheal and respiratory diseases are among the main causes of mortality and morbidity. In Uganda, cities are facing proliferation of trade in herbal medicines (HM), including those for diarrhea and/or cough. Information on the economic, and the ethnopharmacological aspects of these HM is scarce, deterring the sector from achieving optimal capacity to support national development. We profiled the anti-diarrhea and/or anti-cough HM, and the basic economic aspects of HM trade in Kampala city, to support ethnopharmacological knowledge conservation and strategic planning. Methods A cross-sectional survey was conducted on 65 herbalists using semi-structured questionnaires. This was supplemented by an observational survey using a high-resolution digital camera. Data were collected following the guidelines for research on HM, established by Uganda National Drug Authority, and World Health organization. Results Eighty-four plant species from 41 families were documented. Fabaceae and Myricaceae had the highest number of species (9, 10.7% each). Citrus limon (L.) Osbeck was the most commonly cited for cough, with a relative frequency of citation (RFC) of 1.00, and its relative medical importance was not significantly different from the other top 5 species except for Azadirachta indica A.Juss (RFC = 0.87). Entada abyssinica A. Rich (RFC = 0.97) was the most cited for diarrhea. Trees (34, 40.5%) were mostly used, and mainly harvested from wild habitats (55.2%) in 20 districts across Uganda. These HM were mainly sold as powders and concoctions, in markets, shops, pharmacies, and roadside or mobile stalls. The highest prices were Uganda Shillings (UGX) 48,000 ($13.15)/kg for Allium sativum L, and UGX 16,000 ($4.38)/kg for C. limon. All participants used HM trade as a sole source of basic needs; majority (60.0%) earned net monthly profit of UGX. 730,000 ($200) ≤ 1,460,000 ($400). The main hindrances to HM trade were the; disruptions caused by the COVID-19 pandemic (n = 65, 100%), and the scarcity of medicinal plants (58, 89.2%). Conclusion There is a rich diversity of medicinal plant species traded in Kampala to treat diarrhea and cough. The HM trade significantly contributes to the livelihoods of the traders in Kampala, as well as the different actors along the HM value chain throughout the country.

Biogenic Synthesis of Bi-Metallic (Zn-Cu) Nanoparticles by Leaf Extract of Citrus Limon and Evaluation of its Antibiofilm Activity Against E. coli

The rapid hike in the usage of metallic as well as non-metallic nanoparticles demands their increased synthesis. In our study we synthesized bimetallic Zn-Cu nanoparticles using the greener route i.e. dry leaves powder of Citrus limon as it is environment-friendly, cost-effective, has a high surface area to volume ratio and hence superior over monometallic nanoparticles synthesized via physical or chemical approach. UTI is the most common nosocomial infection and the bacteria associated with it usually is E. coli. This pathogen forms biofilm and makes it difficult to treat the disease in less time. Hence, antimicrobial as well as antibiofilm activity of synthesized bimetallic nanoparticles was checked against E. coli. Our experimental procedure involved the preparation of ethanolic plant extract using dry leaf powder followed by synthesis of bimetallic nanoparticles. Particles were then characterized by using biophysical techniques such as FTIR, Powder-XRD and SEM-EDX. Next, we identified bacteria isolated from environment and hospital source and prepared their pure cultures. Lastly, we carried out the antibacterial and antibiofilm activity of synthesized nanoparticles against isolated E. coli. Particles showed the colour change from blue to green upon synthesis and were found to be a triclinic primitive type with an average particle size calculated to be 27.76nm as seen in PXRD. FTIR analysis gave characteristic peaks of functional groups. SEM-EDX confirmed successful doping and grain size of the particle. Bacteria isolated from samples showed pink rods in gram staining indicating gram-negative bacilli. Biochemical findings confirmed E. coli in samples. Characteristic zones of inhibition in range 12-18mm establish good antibacterial properties with MIC of synthesized nanoparticles <0.5mg/ml and crystal violet assay assure antibiofilm properties of Zn-Cu. The result of the study can be advantageous to develop an understanding of the development of nano-based medicine for biofilm-producing pathogens.

Modelos de Crecimiento de Frutos de Limonero 'Eureka' de la Provincia de Corrientes, Argentina

El objetivo de este trabajo fue modelar el crecimiento de limonero ‘Eureka’ (Citrus limón (L.) Burn f) injertado sobre Limón Rugoso (Citrus jambhiri Lush), desde los 60 días después de plena floración hasta la cosecha, en plantaciones comerciales, de la provincia de Corrientes, Argentina. Para ello se registró el diámetro ecuatorial de frutos desde los 60 días después de plena floración hasta el momento de cosecha en cuatro ambientes de la provincia de Corrientes, Argentina. Para describir el crecimiento se compararon los modelos no lineales de tipo sigmoideo: logístico, Gompertz y monomolecular. Se utilizaron como criterios de selección de los modelos: AIC, BIC y el CME (cuadrado medio del error). La precisión del modelo seleccionado se obtuvo mediante validación cruzada. Los modelos seleccionados para describir el crecimiento de frutos de limonero ‘Eureka’ fueron los modelos monomolecular y logístico, los cuales tuvieron un error de estimación que fue medido en términos del CME con valores menores a 20,03. Los parámetros estimados para los modelos seleccionados resultaron significativos (p &lt; 0,01). De esta manera, productores, y empresas exportadoras citrícolas de la región podrán contar con una herramienta con la que puedan predecir la producción al momento de cosecha y así para prever estrategias de comercialización.

Screening plants extracts for Antifungal activity against Rhizoctonia solani

The adverse effect of pesticides used for controlling pests and the diseases caused by them is extensively rising. To overcome this harmful environmental impact, alternative methods are being studied and developed. Out of many possible methods, one effective method is to use plant extracts which embodies natural substances having antifungal properties. In an attempt towards enhancement of sustainable antifungal approach, four different concentrations of four plant extracts Citrus limon, Azadirachta indica, Ocimum gratissimum and Acalypha indica, were tested for their antifungal activity against Rhizoctonia solani, which is a serious threat for plants, and is responsible for considerable crop and yield losses. The aim of this study is to minimize yield losses and to regain the attention of formers towards exploiting natural resources for diseases control. From the results, it can be concluded that different concentrations of plant extracts have caused substantial inhibition in the mycelial growth of R. solani. The leaf extract of Ocimum gratissimum was highly effective in inhibiting mycelial growth, at the concentration of 500mg/ml of extract followed by Citrus limon, Azadirachta indica, and Acalypha indica. These plants might have potential for the development of natural fungicide for the management of diseases caused by fungal pathogens. Also, fungicides developed from these botanical extracts can prove to be highly effective for the management of plant diseases and would be simply obtainable, nonpolluting, biodegradable and economical.

Effect of citrus fruit (Citrus sinensis, Citrus limon and Citrus aurantifolia) rind essential oils on preservation of chicken meat artificially infected with bacteria

Essential oils (EOs) obtained from a wide variety of plants have become popular with increased scientific interest as potential natural agents for food preservation. Two concentrations of rind EOs (400 mg/ml and 200 mg/ml) from three species of citrus fruit; Citrus sinensis (Sweet orange), Citrus limon (Lemon), and Citrus aurantifolia (Lime) were used to treat fresh chicken meat inoculated with Escherichia coli ATCC 25922, Salmonella typhi ATCC 20971 and Salmonella enterica ATCC 14028 to evaluate their protective abilities on bacteria-contaminated meat The EOs were extracted from the ground rinds by hydro-distillation. Alongside the EOs, sodium nitrate (NaNO3) was used as a positive control preservative. A viable count was carried out to determine the bacteria load reduction on the inoculated fresh chicken meat. After 24 hours of treatment, the results showed that the EOs had no adverse effect on the physical attributes of the meat: the color and smell of the chicken meat were unaltered compared with the negative control (None EO and NaNO3 treated meat) that showed evidence of putrefaction through color change and foul smell. The two- lime rind EOs concentrations used to treat the Escherichia coli ATCC 25922 inoculated meat reduced the viable count of the organism by 7.9 log compared to the Escherichia coli ATCC 25922-inoculated meat which received no rind EOs or NaNO3 treatment. Other results showed that sweet orange (SO) rind EOs (400 mg/ml and 200 mg/ml) treatment of meat inoculated with Salmonella enterica ATCC 14028 had similar but mild preservative effects as both treatments reduced the log of the bacteria by 1.1 and 0.8, respectively. In comparison with NaNO3, the EOs treatment had a significant (p<0.05) preservative effect on the bacteria-inoculated meats. Findings from this study, therefore, suggest that Citrus spp. rind EOs have good potential as natural preservative for chicken meat. However, notwithstanding the relative positive organoleptic results observed in this study, further investigations on the prolonged preservation effect of the EOs on the physical attributes of fresh chicken meat need to be undertaken.

Repellent and Toxicant Effects of Eight Essential Oils against the Red Flour Beetle, Tribolium castaneum Herbst (Coleoptera: Tenebrionidae)

This study was conducted to compare the repellent effect and contact toxicity of eight essential oils (EOs), including Syzygium aromaticum, Allium sativum, Eucalyptus camaldulensis, Lavandula officinalis, Simmondsia chinensis, Matricaria chamomilla, Citrus limon, and Prunus dulcis, against adults of Tribolium castaneum Herbst. Four concentrations (1, 5, 10, and 15% in acetone solvent) of each EO were tested. The 5, 10, and 15% concentrations of S. aromaticum EO had a high repellency effect against T. castaneum compared with A. sativum, E. camaldulensis, L. officinalis, S. chinensis, M. chamomilla, C. limon, and P. dulcis after 30 min of exposure. The repellency test of the S. aromaticum, E. camaldulensis, L. officinalis, M. chamomilla, C. limon, and P. dulcis EOs on T. castaneum has shown that the mortality percentages enhanced with the increase in the EOs concentration and also with the exposure time. The 15% concentration of P. dulcis and M. chamomilla EOs have a significant impact on the mortality rate of T. castaneum compared with S. aromaticum, A. sativum, E. camaldulensis, L. officinalis, and S. chinensis after the 24 h of contact test. Moreover, the 15% concentration of the C. limon EO caused a greater mortality percentage compared with S. aromaticum, A. sativum, E. camaldulensis, and L. officinalis. It could be concluded that using the S. aromaticum EO as a repellent oil and using P. dulcis, M. chamomilla, and C. limon for contact toxicity to treat the flour infested by T. castaneum can play an important role in protecting stored grains and their products.