Effect of digester surface area on biogas yield

Poultry manure, cow dung and swine manure were digested in cube-shaped anaerobic digesters of equal volume but different surface areas (SAs) (5.38, 10.0 and 11.6 dm2) in a two-factor experiment. The digesters were agitated once a day during the experiment. The results showed that neither the manure type nor SA affected (p > 0.05) substrate temperature and pH, but both had (p ≤ 0.05) on biogas yield (BY. Poultry manure had the highest BY followed by swine manure and cow dung (1.00, 0.59 and 0.11 dm3 kg-1 VS fed day-1, respectively). Within the SAs investigated, BY increased as digester SA increased (0.27, 0.68 and 0.74 dm3 kg-1 VS fed day-1 for 5.38, 10.0 and 11.6 dm2, respectively). The results of the regression analysis showed that digester diameter to substrate height ratio and BY had a polynomial relationship with a dome-shaped curve, indicating that BY would not keep increasing exponentially with increase in digester SA at the expense of substrate height

Influence of Vermicast on Early Growth of Black Afara (Terminaliaivorensis A. Chev.) Seedlings

This study assessed the effect of vermicast on the early growth of Terminalia ivorensis A.Chev. (Black Afara) seedlings which belongs to the family Combretaceae. Seedlings were raised on Vermicast (100%), Vermicast + Topsoil (1:1,) and topsoil media. There were three (3) treatments, replicated four (4) times and laid in Completely Randomized Design (CRD). The experiment was monitored for 12 weeks and the following variables were assessed, plant height (cm), stem diameter (mm), leaf production and the leaf area (cm2 ). Data collected were subjected to descriptive statistics and Analysis of Variance (ANOVA). Results revealed that the seedling growth parameters measured were not significantly affected by the vermicast treatments at 5% probability level, except plant height. The best performance was observed in the seedlings raised with T2 (Vermicast + Topsoil) in plant height, stem diameter, leaf production and leaf area with mean values of 28.55cm, 0.55mm, 18.25 and 38.87cm2 respectively while the least performance was recorded in T3 (100% top soil) in plant height, stem diameter, leaf production and leaf area with mean values of 22.06cm, 0.49mm, 15.25 and 49.72cm2 respectively. It is therefore recommended that 50% vermicast should be used to improve the growth media in order to enhance the early growth of Terminalia ivorensis seedlings at the nursery stage.Keywords: Vermicast, Terminalia ivorensis, Early Growth, Seedling

Volatile constituents from Samanae saman (Jacq.) Merr. Fabaceae

In this work, we report on the constituents identified from the fruits volatile oil of Samanae saman (Jacq.) Merr., Fabaceae. The volatile oil was obtained by hydrodistillation in an all glass Clevenger-type apparatus. The oil content was 0.23% (w/w), on a dry weight basis. The oil was analyzed by GC-MS. Altogether, 32 compounds were identified accounting for 99.7% of the total oil content. Fatty acids comprised 69.1% of the oil content; with palmitic acid (55.6%) being the most singly abundant constituent. 1,8-Cineole (15.9%) was the quantitatively significant constituent of the terpenoids

Levels of Potentially Toxic Metals In Selected Herbal Medicines In Lagos, Nigeria

The increasing popularity and widespread use of herbs as alternative medicine has sparked an interest in understanding their safety. Potential toxic metals (PTM) have been identified as a risk to human health through the usage of herbal medicines. This study aimed to assess the level and pH of PTM (Fe, Cu, Pb, Cd, Ni and Zn) in selected herbal medicines sold in Lagos, Nigeria. Eight commonly consumed herbal medicines: E-5000, MT-CAPS, B-CAPS, DD-TEA, YC-BITTER, JHD-POWD, KA-POWD, and H-CAPS were analysed for PTM using Atomic Absorption Spectrophotometer after wet digestion of the medicines. The highest concentration (mg/kg) of Fe (257±0.1), Pb (33.8±0.01) and Zn (38.9±0.01) were found in KA-POWD. The result also showed that JHD-POWD had the highest concentration amount of Ni (54.0±0.01 mg/kg), while B-CAPS had the highest concentration of Cu (4.14 ±0.02 mg/Kg).  All the herbal medicines analysed are high in Fe content with range between 6.2 to 257 mg/kg. The pH values ranged between slightly acidic of 5.6 - 5.7 to slightly alkaline of 8.0 -8.65.  Twenty five percent of herbal medicines analysed had concentrations of Pb above the the WHO limits of 10 mg/kg, while all the samples had Cd above the permissible limits of 0.3 mg/kg. KA-POWD had the highest concentrations of Pb, Zn, Fe, and Cd determined.  All other PTMs in the other samples analysed are below the recommended permissible limits. Keyword: Capsules; Herbal medicine; Lagos; Potentially toxic metals content; Powdered

Evaluation of biogas yield from water leaf plant (Talinum triangulare)

The exploitation of plant materials for renewable source of energy in form of biogas is of growing interest. Water leaf (Talinum triangulare), an abundantly available underutilized herbaceous perennial plant in South-Western Nigeria was digested to assess its biogas yield. Water leaf (WL) and Water hyacinth (Eichhornia crassipes) alone, and mixtures of water hyacinth (WH) and WL at ratios 70:30, 50:50 and 30:70 (w:w dry basis) were digested to compare biogas yields. Fixed amount of cow dung was added to each treatment before digestion in batch-type anaerobic digesters for 70 days. The results of the study showed that feedstock mixture affected (p ≤ 0.05) pH and biogas yield. WL proved to be prolific in biogas as it yielded approximately six times greater than WH. The mixture of WH and WL improved biogas yield than WH alone. The mixture WH:WL at ratio 30:70 produced the highest average yield of 363.7 cm3 kg-1 VS fed day-1 which was approximately 7.8 and 1.2 times greater than the yields obtained from WH and WL alone, respectively

Effects of Carbon to Nitrogen Ratio and Turning Frequency on Composting of Chicken Litter in Turned-Windrow Piles

Raw chicken manure was co-composted with sawdust in turned-windrow piles to understand the effects of carbon to nitrogen (C:N) ratio and turning frequency (TF) on composting. Carbon to nitrogen ratios of 20:1, 25:1 and 30:1, and turning frequencies of every 2 days and every 6 days were experimented. Properties of the chicken litter (chicken manure + sawdust) periodically monitored during the composting process were moisture content (MC), temperature, pH, total nitrogen (TN), total carbon (TC) and C:N ratio while dry matter (DM), total phosphorus (P) and total potassium (K) were examined at the end of composting. During composting, MC of the piles was periodically replenished to 55%. The results showed that C:N ratio had significant (p ≤ 0.05) effect on pile temperature, TN, TC, C:N ratio, DM, P and K while TF had significant (p ≤ 0.05) effect on pile temperature, pH, TC, C:N ratio and K. A significant part of the TN losses were attributed to NH3 volatilization while that of the TC losses were attributed to OM degradation. It was observed that moisture loss increased as C:N ratio and TF increased. All treatments reached stability at about 87 days as indicated by the decline of pile temperatures to values close to ambient temperature

A new chemical form of essential oil of Hyssopus officinalis L. (Lamiaceae) from Nigeria

Essential oil obtained by hydrodistillation from the air-dried leaves of Hyssopus officinalis L. (Lamiaceae) collected in Ajangbadi area, West of Lagos, Nigeria, was analyzed comprehensively for its constituents by means of gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The monoterpene hydrocarbons, á-pinene (70.9%) and â-pinene (10.9%) are the dominant constituents of the oil of H. officinalis. A cluster analysis was performed for comparison and characterization of H. officinalis essential oil from Nigeria with other oils reported in the literature from different locations across the world, and reveals chemical variation in this species with at least 8 different chemotypes. The compositional pattern of Nigerian oil sample was being reported for the first time and represents another chemotype of the oil of H. officinalis

Chemical compositions of Casuarina equisetifolia L., Eucalyptus toreliana L. and Ficus elastica Roxb. ex Hornem cultivated in Nigeria

AbstractEssential oils were obtained by separate hydrodistillation of three different plants cultivated in Nigeria and analysed comprehensively for their constituents by means of gas chromatography (GC) and gas chromatography-mass spectrometry (GC–MS). The leaf essential oil of Casuarina equisetifolia L. (Casuarinaceae) comprised mainly of pentadecanal (32.0%) and 1,8-cineole (13.1%), with significant amounts of apiole (7.2%), α-phellandrene (7.0%) and α-terpinene (6.9%), while the fruit oil was dominated by caryophyllene-oxide (11.7%), trans-linalool oxide (11.5%), 1,8-cineole (9.7%), α-terpineol (8.8%) and α-pinene (8.5%). On the other hand, 1,8-cineole (39.4%) and α-terpinyl acetate (10.7%) occurred in large quantities in the essential oils of the leaf of Eucalyptus toreliana L. (Myrtaceae). The oil also features high levels of sabinene (5.9%), caryophyllene-oxide (4.7%) and α-pinene (4.2%). The main compounds identified in the leaf oil of Ficus elastica Roxb. ex Hornem. (Moraceae) were 6,10,14-trimethyl-2-pentadecanone (25.9%), geranyl acetone (9.9%), heneicosene (8.4%) and 1,8-cineole (8.2%)

Essential Oil of Phyllanthus reticulatus Poiret from Nigeria

The chemical composition of the essential oil obtained by hydrodistillation from the leaves of Phyllanthus reticulatus Poiret (Euphorbiaceae) growing in Nigeria has been studied. The constituents of the oil were analyzed by means of gas chromatography (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). Monoterpenes (64.9%) were the dominant class of compounds, followed by sesquiterpenes (23.0%). The major constituents were α-pinene (6.0%), sabinene (7.6%), β-pinene (18.1%), linalool (6.9%) and camphor (7.7%), among the monoterpenes, and β-caryophyllene (11.9%) and germacrene D (8.6%) among the sesquiterpenes. This is the first report on the volatile constituents of Phyllanthus reticulatu

Essential oil constituents of Eclipta prostrata (L.) L. and Vernonia amygdalina Delile

The chemical composition of the essential oils from the leaves and stem bark of Eclipta prostrata (L.) L. and the aerial parts of Vernonia amygdalina Delile (Asteraceae) have been analyzed by capillary gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The investigation led to the identification of 33 and 30 compounds in the oils of the leaves and stem of E. prostrate, respectively, and 40 compounds in the oil of V. amygdalina. While the oil of the leaves of E. prostrata was highly dominated by sesquiterpenoids (89.3%), the stem bark was comprised of sesquiteprenoids (47.7%), straight chain hydrocarbons (25.6%) and monoterpenoids (11.1%). The main constituents of both oils were β-caryophyllene (47.7% and 15.9%) and α-humulene (31.8 and 12.9%) in the leaves and stem, respectively. In addition, ( E)-β-farnesene (10.0%) was also identified in significant amount in the stem bark. On the other hand, the major component of V. amygdalina oil was α-muurolol (45.7%)