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.

Ethanolic extract of Ocimum Gratissimum (Scent Leaf) leaves improves haematological parameters in restrain-stressed rats

Stress alters system physiology as well as humoral immunity and hematology, and its problems have become a global issue. The present study was designed to investigate effects of the use of traditional herbs such as Ocimum gratissimum (OG) on hematological parameters in stressed rats. We subjected adult female Wistar rats to prolonged restrained stress for 14 days and administered 100 mg/kg, 200 mg/kg, 400 mg/kg of OG leaf extract and Vitamin C respectively for 14 days. Animals (200-250 g) were sacrificed by cervical dislocation at day 0, day 7 and Day 14 so as to assess the dose and time dependent effect of the extract. Findings revealed that OG leaf extract caused a dose-dependent significant protective effect (P<0.05) on the packed cell volume (PCV), total white blood cell (WBC) count, haemoglobin (Hb), platelet count and total red blood cell (RBC) count compared to Vitamin C treated group. Our study confirms that OG leaf extract is better at improving haematological parameters of restrain stressed rats compared to Vitamin C and it was more effective in animals that were administered 100 mg/kg and 400 mg/kg of the extract. The result indicates that OG leaf extract could alleviate prolonged exposure to stress by lowering PCV, total WBC, total RBC, hemoglobin count and elevating blood platelets.

Response of Broiler Chickens to Oral Administration of Ocimum Gratissimum Leaf Extracts

The study was carried out on one hundred and ninety-five day-old broiler chicks of cobb500 to study the effect of Ocimum gratissimum leaf extracts on growth performance, blood profile, microbial population in the faecal and gut samples. The chicks were randomly selected into five groups with thirty-nine chicks per group and each group replicated thrice. The groups were: control (synthetic antibiotics), extracts from 200 g fresh leaf, 400 g fresh leaf, 40 g air-dried leaf and 80 g aid-dried leaf per litre of water respectively. Data collected were subjected to one-way Analysis of Variance. The growth performance except mortality was similar (P>0.05) across the groups. Albumin, urea, cholesterol, alkaline phosphate and sodium were influenced (P<0.05) at the starter phase while only alkaline phosphate was significantly (P<0.05) highest in birds on 400 g of fresh leaf extract at the finisher phase. Neutrophil was highest (P<0.05) in birds on 400 g of fresh leaf extract while those on 200 g had higher values of lymphocytes and eosinophil at starter phase. At finisher phase, birds on antibiotics and 80 g of air-dried leaf extract had higher (P<0.05) white blood cell. Faecal total microbial population was least (<0.05) in birds on antibiotics and 200 g fresh Ocimum gratissimum leaf extract at starter phase. The study concluded that the adoption of Ocimum gratissimum leaf extract as prophylactic treatment against bacteria should be encouraged among poultry farmers.

Determination of Heavy Metals in Soil around Amasoma Community in Bayelsa State, Nigeria

Aims: Anthropogenic activities such as crude oil exploration and exploitation has led to the suspicion of heavy metals contamination in the study area. This study investigated the concentration of zinc, nickel, lead and cadmium in the soil extracted from the area where Scent Leaf (Ocimum gratissimum) and Pawpaw tree (Carica papaya) are grown in Amassoma community, Bayelsa State, Nigeria. Study Design: Scent leaf (Ocimum gratissimum) and Pawpaw tree (Carica papaya) soils from where these plants are grown were randomly collected for heavy metal analysis from within Amassoma community in Southern Ijaw Local Government Area of Bayelsa State, Nigeria Place and Duration of Study: This study was carried out in Biological Sciences, Faculty of Science, Niger Delta University, Wilberforce Island, Amassoma, Bayelsa State between March 2019 to September 2019 Methodology: Scent leaf (Ocimum gratissimum) and Pawpaw tree (Carica papaya) soils were digested and analyzed for heavy metals using Atomic Absorption Spectrophotometer (AAS, model S471096). The method used was wet-ashing method for the analysis. Results: the concentrations of Lead (Pb), Nickel (Ni), Cadmium (Cd), and Zinc (Zn), in pawpaw soil and scent leaf soil. From the sample data analysis, the average lead (Pb) contents in pawpaw soil and scent leaf soil were 1.283 mg/kg and 1.44 mg/kg respectively. The average Cadmium (Cd) in pawpaw soil and scent leaf soil were 0.256 mg/kg and 0.256 mg/kg respectively. The average Nickel (Ni) compositions in pawpaw soil and scent leaf soil were 4.71 mg/kg and 5.09 mg/kg respectively. While the Average Zinc (Zn) in pawpaw soil and scent leaf soil is 2.280 mg/kg and 2.160 mg/kg respectively. The soil analyzed for heavy metals were below the threshold target values recommended by the WHO. Conclusion: The Scent leaf (Ocimum gratissimum) and Pawpaw tree (Carica papaya) soils analyzed for heavy metals were below the permissible limit recommended by WHO for soil safety. The result from the present study revealed that there may not be soil contamination as a result of the selected heavy metals, however, It is recommended that caution should be taken in regulating the anthropogenic activities that may tend to elevate the level of heavy metals in the surrounding to prevent contamination of soil over time which could be detrimental to the health of the populace.

Determination of Heavy Metals (Lead, Zinc, Nickel and Cadmium) in Medicinal Plants (Scent Leaf and Pawpaw) in Bayelsa State, Nigeria

Aims: This study investigated the level of zinc, nickel, lead and cadmium in selected medicinal plants - Scent Leaf (Ocimum gratissimum) and Pawpaw (Carica papaya) that are traditionally used in alternative medicine in Amassoma community, Bayelsa State, Nigeria. Study Design: Scent leaf (Ocimum gratissimum) and Pawpaw (Carica papaya) from where these plants are grown were randomly collected for heavy metal analysis from within Amassoma community in Southern Ijaw Local Government Area of Bayelsa State, Nigeria Place and Duration of Study: This study was carried out in Biological Sciences, Faculty of Science, Niger Delta University, Wilberforce Island, Amassoma, Bayelsa State between March 2019 to September 2019 Methodology: Scent leaf (Ocimum gratissimum) and Pawpaw (Carica papaya) were digested and analyzed for heavy metals using Atomic Absorption Spectrophotometer (AAS, model S471096). The method used was wet-ashing method for the analysis. Results: The result showed that the concentration of Lead in the pawpaw fruit with 5.99mg/kg and pawpaw seed with 3.72mg/kg, were above the WHO permissible limit. While the concentration of Cadmium in the pawpaw fruit, pawpaw leaf, pawpaw seed and scent leaf with 1.32mg/kg, 0.96mg/kg, 0.21mg/kg, and 0.59mg/kg, were all above the permissible limits. Again, Zinc in the pawpaw fruit, pawpaw leaf, pawpaw seed and scent leaf were 2.52mg/kg, 2.53mg/kg, 5.30mg/kg, and 0.79mg/kg respectively, and these are also above the permissible limit. While that of the concentration of Nickel in the pawpaw fruit, pawpaw leaf, pawpaw seed and scent leaf were observed to be within permissible limit. Conclusion: It is therefore recommended that caution should be taken when such plants are to be used as alternative to conventional medicine as excess of it could pose the risk of bioaccumulation and possible health effects in humans.

De novo assembly, annotation and molecular marker identification from the leaf transcriptome of Ocimum gratissimum L

Ocimum gratissimum L. is a well-known medicinal plant with several therapeutic properties, but molecular studies on this species are lacking. Therefore, we have sequenced the whole transcriptome from the leaves of O. gratissimum and assembled 121,651 transcripts. The transcriptome of O. gratissimum was closely related to Sesamum indicum and Erythranthe guttata in congruence with the molecular phylogenetic relationships among these species. Further, 62,194 transcripts were annotated and classified according to the GO terms concerning the biological process, cellular component and metabolic function. In the KEGG pathway analysis, 34,876 transcripts were mapped to 149 pathways and 1410 of them were involved in the biosynthesis of secondary metabolites. In the phenylpropanoid pathway, 101 transcripts were associated with the biosynthesis of eugenol, the principal constituent of the essential oil of O. gratissimum. In the caffeine metabolism pathway, none of the transcripts was related to caffeine biosynthesis, supportive of the caffeine-free nature of Ocimum. Transcripts coding for the metallothionein were abundant in the leaves, supporting the observation that O. gratissimum is an accumulator of heavy metals. We also identified the 930 transcripts coding for 59 transcription factors families with myeloblastosis transcription factors being the most predominant. About 6500 simple sequence repeats were identified, which will be useful in DNA marker-based applications. This is the first report of the leaf transcriptome of O. gratissimum, which will serve as an essential resource for further molecular studies in this important medicinal species.