Applied Botany

The seeds of Azadirachta indica A. Juss. popularly known as neem collected from five cities of Accra metropolis was studied. Trees with wide girth and different seed weight were observed. Maximum residual oil content was noticed in trees from Haatso. Weight of the seeds had no effect on the oil yield. Seed oil content in most of the cities was not significantly correlated with morphological parameters of seeds. A.indica seed oil extracted was analyzed for their physicochemical properties such as viscosity at 28 ^oC (0.07 kg/ms), pH (5.7), acid value (1.102 ml/g), iodine value (71.0 gI₂/100g) and free fatty acid value (48.35 ml/g). The maximum mean percentage oil obtained (52.5 %) makes the commercialization of the seeds of Azadirachta indica in Ghana a possible and profitable venture. The result also confirms the oil to be good quality and can find application in industrial purposes.

Hexane, diethyl ether, dichloromethane and ethyl acetate extracts of twenty five plant species, including fourteen varieties of leaves, five varieties of whole plants, two varieties of barks and one variety of flower, fruit, seed and root were tested for ovicidal activity against Culex quinquefasciatus at 1000 ppm. During preliminary screening, significant ovicidal activity was observed in all four solvent extracts of Cleistanthus collinus, Hydrocotyle javanica, Leucas aspera, Murraya koeingii, Sphaeranthus indicus and Zanthophyllus limonella.  Solvent crude extracts of plants showing maximum ovicidal activity were selected and treated at 500 ppm. The percentage of egg hatchability significantly reduced in different solvent extracts of above mentioned plants and eggs treated with different plant extracts varied from 26.59 per cent  in diethyl ether extract of Murraya koeingii  to 82.61 per cent in hexane extract of Leucas aspera.

Natural dyes are biodegradable eco friendly. In the present study an attempt was made to dye silk and cotton with the dyes extracted from the flowers of Delonix regia, Nyctanthes arbortristis, Tagetes erecta and Peltophoram petrocarpum using two different mordant, copper sulphate and potassium dichromate. The fabrics dyed in Nyctanthes have found to be good colour fastness when they subjected to involve in qualitative test.

The in vitro antibacterial activity of flavonoid and alkaloid extracts of various plant parts of V. negundo and A. paniculata was investigated using Disc Diffusion Assay against four Gram negative (E. aerogens, R. planticola, A. tumefaciens and K. pneumoniae) and one Gram positive bacteria (B. subtilis). Minimum inhibitory concentration of the extracts was evaluated by micro broth dilution method, while minimum bactericidal concentrations were determined by sub culturing the relevant samples. The extracts exhibited antimicrobial activities with zones of inhibition ranging from 9 to 23.5 mm. A. tumefaciens was found to be most susceptible organism in the investigation against which all the extracts showed positive response. Stem free flavonoid extract of V. negundo and stem bound flavonoid extract of A. paniculata was recorded as most active extract as it showed significant zone of inhibition against all the tested pathogens. The range of MIC and MBC was recorded 1.25-0.039mg/ml. Results of the present study reveal that extracts of both the selected plants are showing great antimicrobial potential against tested pathogen, and may be exploited for future antibacterial drugs.

The exploitation of biologically active secondary metabolites for useful applications, including therapeutic drugs, is far from new. Since ancient times, nature has been recognized as an important source of potential drugs; examples of early uses and benefits of natural products for human can be found in most major civilizations (Newman et al., 2000; Constantino et al., 2004). The use of natural products for medical purposes slowly developed into the scientific field of pharmacogenosy. However, this was not until the early 1800’s when the active principles from plants were isolated and characterized. Among the first active principles isolated were morphine atropine, colchicines and caffeine (Newman et al., 2000). Morphine, atropine, and caffeine are today listed as core medicines in the World Health Organization’s “Essential Drugs List”, which is a list of minimum medical needs for basic health care systems (WHO, 2005).

An attempt has been made to survey biodiversity of arbuscular mycorrhizal (AM) fungi associated with five xerophytes from Ghodnadi area Dist. Pune, Maharashtra. The xerophytes surveyed were Argemon Mexican, Linn., Aristolochia bracteata, Rrtz.,  Chlorophytum tuberosum, Baker., Scilla indica, Baker., Tribulus terestris, Linn., Soil samples and roots of these plants were collected from four different localities. Five genera with twenty one species were reported from Ghodnadi area. The genus Glomus was dominant with 13 species. It was followed by Acaulospora with 4 species, two species of Scutellospora  were reported.  Whereas one species each of Gigaspora and Sclerocystis was reported from above area. The maximum number of AM propagules per 100 gm soil was 1980 and minimum was 4 per 100 gm soil.  The percentage root infection was ranging between zero and 90 percent.

Abstract Aim of present study was to evaluate in vitro antimicrobial activity of crude extracts of Acacia nilotica. The extracts exhibited antimicrobial activities with zones of inhibition ranging from 6 to 22 mm and exhibited appreciable activity against all the clinically important bacterial and fungal species. Overall maximum Inhibition zone (22mm) was observed in extract of methanol and chloroform (75:25) against Bacillus subtilisand minimum (4mm) in extract of methanol and chloroform (50:50) against Dreschlera avenacea. Phytochemical screening revealed the presence of carbohydrates, proteins, alkaloids and flavonoids in the extracts. The antimicrobial effect of the extract was compared with the standard drugs (Ciprofloxacin for bacterial and ketokenazole for fungus). Crude extracts of A.nilotica inhibited the growth of various bacteria and fungi thus showed its broad spectrum antimicrobial potential, which may be employed in the management of microbial infections.

The present study deals with impact of physical factors on extracellular cellulase activity of some dominant post-harvest fungi. Post-harvest fungi were isolated from different varieties of papaya fruits by agar plate method. Out of 20 species 10 species of fungi were selected to study their cellulase enzyme activity. Different physical parameters such as light, incubation period, temperature and pH were studied in order to determine the optimum conditions for cellulase production of ten dominant fungi. The cellulase present in the broth was assayed by cup-plate method. It is observed that cellulase activity of post-harvest fungi was found to be optimum at temperature 200C, pH 6.0-6.5, incubation period of 20 days and continuous light

The research paper represents a brief analysis of physico-chemical characteristics of three different water bodies viz. earthen pond, cemented pond and lake located at Bhimtal, Nainital, Uttarakhand during winter season. Air temperature, water temperature, pH, DO, free CO2, total alkalinity, total hardness, total nitrogen, nitrite, nitrate, phosphate, ammonium and silicate were the physico-chemical parameters observed during the experimental period.

The in vitro antimicrobial activity of crude methanolic extracts of various plant parts of Phyllanthus niruri was investigated. The extracts exhibited antimicrobial activities with zones of inhibition ranging from 6 to 16 mm. All the extracts exhibited appreciable activity against all the clinically important bacterial and fungal species clinically investigated. Maximum Inhibition zone (16mm) was observed in seeds against Staphylococcus aureus and minimum in roots (5mm) against E. coli. Phytochemical screening revealed the presence of carbohydrates, proteins, alkaloids and flavonoids in the extracts. The antimicrobial activity of the extract was compared with the standard drugs. The ability of the crude extracts of P. niruri plant parts to inhibit the growth of various bacteria and fungi showed its broad spectrum antimicrobial potential, which may be employed in the management of microbial infections.