Influence of egg shell as heterogeneous catalyst in the production of biodiesel via transesterification of Jatropha oil

The increase in energy demand together with the negative global environmental impacts of using fossil fuel for energy generations brings a question on dependability on it for sustainable economic growth. The way out is the use of renewable sources of energy such as biodiesel which has significant advantages over its counterpart (fossil fuel). Biodiesel can be produced through various methods such as transesterification, micro emulsion and pyrolysis. The influence of egg shell as heterogeneous catalysts in the production of biodiesel via transesterification of Jatropha oil was investigated. The physical and chemical properties of the catalyst were studied using scanning electron microscopy (SEM) and Xray fluoroscopy (XRF) characterizations. The crude Jatropha oil was transesterified and 0.1 wt%, 0.2 wt%, 0.3wt%, 0.5wt% and 0.5wt% of egg shell were used as heterogeneous catalyst during transesterification process. Fourier Transform Infrared (FTIR) was used to determine the functional group of the samples. SEM and FTIR characterizations indicate the presence of dispersed particles on the catalyst and ester (biodiesel) on the samples respectively. The maximum percentage of biodiesel yield is 94.3% at the application of 0.2wt% egg shell as catalyst using 1:6 oil to methanol ratio in 1hr at 60-65℃. This indicated that the egg shell has high potential to be used as catalyst in the production of biodiesel via transesterification of Jatropha oil

Introduction of household biogas digesters in rural farming households of the Maluti-a-Phofung municipality, South Africa

The study aimed to introduce biogas as an alternative source of energy for rural cattle farmers in the Maluti-a-Phofung municipality in the Free State Province, South Africa. To augment the rural farming community’s adoption of the biodigester technology the following initiatives were undertaken: (i) a situational analysis (or diagnostic survey); (ii) training on biogas production in an integrated crop-livestock-bioenergy system; (iii) installation of the biodigesters; and (iv) monitoring and evaluation of the biogas production. Results on the diagnostic survey showed that the main source of energy for cooking was wood in all the farms and availability of water was not a constraint. Prefabricated biodigesters of 6m3 -12m3 were installed in all the households and, after continual feeding of the units with cattle dung, the production of biogas increased gradually. Monitoring of biogas production showed that, in two-thirds of the households, 80% of their cooking needs were met in summer, while in winter biogas production was minimal due to extremely cold weather. Challenges faced included non-adherence to a feeding regime – resulting in a blockage of the biodigester – and lack of feeding. Generally, farmers in the study area showed a high appreciation of the biodigester technology

2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of extracts from Aloiampelos striatula

Hexane, chloroform, acetone, methanolic and water extracts from leaves and stem-bark of Aloiampelos striatula were evaluated for their antioxidant activity by 2,2-diphenyl-1- picrylhydrazyl (DPPH) radical scavenging assay. The hexane, chloroform, acetone, methanolic and water extracts from leaves of A. striatula showed scavenging activity ranging from 10.30±0.41 - 30.14±1.4, 30.49±0.85 - 45.95±0.22, 38.45±0.49 - 51.65±0.95, 34.83±1.53 - 64.98±0.45 and 54.37±1.24 - 66.74±0.89%, respectively, at various concentrations. The hexane, chloroform, acetone, methanolic and water extracts from stem -bark of A. striatula showed scavenging activity ranging from 12.53±3.07 - 29.81±2.43, 17.80±5.17 - 37.20±2.13, 6.15±0.24 - 62.79±3.82, 38.23±1.18 - 67.32±0.55 and 3.16±0.40 - 70.66±0.18%, respectively, at various concentrations. Additionally, the IC50 values of these extracts were also determined and were found to be in the range of &lt;200 to &gt;3000 µg/mL. The positive control, vitamin C, showed an IC50 value of &lt;200 µg/mL. The therapeutic applications of A. striatula are often in traditional Basotho medicine in the Kingdom of Lesotho, which include treating skin problems, high blood pressure, sexually transmitted illnesses, common colds, blood cleansing, stomach ailments and dressing of wounds. Further studies on this plant are required to explore this plant for its commercial applications.</jats:p

Lack of modulatory effect of asparagus, tomato, and grape juice on cyclophosphamide-induced genotoxicity in mice

Studies on agents that modulate carcinogen-induced genotoxic effects in experimental animals are used to assess the antimutagenic or anticarcinogenic properties of putative chemopreventivecompounds. We investigated the potency of asparagus-, tomato- and red grape-juice to modify the proportion of polychromatic erythrocyte (PCE) and frequency of micronucleated polychromatic erythrocytes (MNPCE) induced by cyclophosphamide (CP) in male NIH mice. Groups of five mice were given the fruit juices (25, 50 or 100%) respectively, ad libitum, for 44 days then intraperitoneally (ip) injected with 40 mg/kg CP and killed 24 h later for cytological preparations and analysis. The control group animals were injected with CP (positive) or purified water (negative). Each group mean of the proportion of PCE and frequency of MNPCE was compared with the negative and positive control usingthe Mann-Whitney test. No statistically significant difference was found between the proportion of PCE in any experimental group and the negative control (

Purification and identification of antibacterial compounds from Euclea crispa subsp. crispa (Ebenaceae) leaves

The isolation, purification and identification of antibacterial compounds from Euclea crispa subsp. crispa reported here, is a continuation of earlier work. Most of the antimicrobial activity was located in an ethyl acetate fraction obtained by means of liquid–liquid extraction. Subsequent purification of this fraction, by means of multiple preparative thin layer chromatography using different solvent systems, revealed the presence of essential oils, bitter principles and saponins, all terpenoid derivatives, as well as alkaloids and phenolic compounds. A terpenoid that tested positive for bitter principles and for saponins, and possessed a steroidlike structure, was isolated and purified from the ethyl acetate fraction. This compound was active against the Gram-negative Moraxella catarrhalis. Also isolated from the ethyl acetate fraction, and showing antimicrobial activity as individual compounds, were five flavonoids identified as catechin, epicatechin, gallocatechin, hyperoside and quercitrin. Of these epicatechin and hyperoside were most active in inhibiting the growth of M. catarrhalis (−), Streptococcus pneumoniae (+) and Haemophilus influenza (−). The isolated flavonoids seemed, in general, to have less activity than the entire ethyl acetate fraction, suggesting that these compounds function in synergy

Phytochemical analysis, total flavonoid, total phenolic contents and ferric reducing power of extracts from leaves and stem bark of Buddleja salviifolia

Chloroform, ethyl acetate and methanolic extracts from leaves and stem bark of Buddleja salviifolia were prepared. The phytochemical profiles, total flavonoid contents (TFC), total phenolic contents (TPC) and ferric reducing power of these extracts were studied. The presence of alkaloids, tannins, phlobatannins, saponins, sterols, flavonoids, coumarins, phenolics, terpenoids, quinones and reducing sugars were identified from these extracts. The TFC of these extracts was found to be in the range of 11.36±0.98 to 30.76±1.15 mg QE/g DW, respectively. The TPC of these extracts was found to be in the range of 175.00±0.41 to 465.27±2.65 mg GAE/g DW, respectively. Additionally, these extracts showed a weak to moderate ferric reducing power compared to ascorbic acid. B. salviifolia finds therapeutic applications in traditional medicine. Further studies are required to commercialize products from this plant.</jats:p

Growth inhibition of plant pathogenic bacteria and fungi by extracts from selected South African plant species

Extracts from 26 plant species representing 16 families, collected in the Free State Province of South Africa, were tested in vitro for their potential to inhibit the growth of eight plant pathogenic fungi and five plant pathogenic bacteria. None of the crude extracts showed any mycelial growth inhibition of the eight test fungi. All of the extracts inhibited the growth of one or more of the five plant pathogenic test bacteria, but to varying degrees. Crude extracts from Acacia karroo and Elephantorrhiza elephantina inhibited the growth of four bacteria, while that of Euclea crispa, Acacia erioloba, Senna italica and Buddleja saligna inhibited the growth of all five plant pathogenic bacteria. Of these, the crude extract of Euclea crispa was clearly superior to the rest as it compared more favourably to that of a commercial bactericide, Dimethyl Dodecyl Ammonium Chloride (DDAC). Subsequently, the Euclea crispa crude extract was fractionated by means of liquid-liquid extraction using four organic solvents, hexane, diethyl ether, chloroform and ethyl acetate, in order of increasing polarity. This was done in an attempt to assess the antimicrobial potential of the more concentrated fractions. Once again, none of the semi-purified fractions showed any antifungal activity. However, antibacterial activity was located in the more polar ethyl acetate fraction indicating that the substances involved were very similar in polarity and/or structure. From this it seems justified to further purify the ethyl acetate fraction of the Euclea crispa extract and attempt to identify the active substance(s) involved

Phytochemical Screening and Antioxidant Analysis of the Ethanolic Extract of Rosehip Seed Press Cake

Aims: Rosehip seed press cake is a waste material in the industrial extraction of rosehip seed oil using cold press process. The current study seeks to evaluate the phytochemical profile, total phenolic content, total flavonoid content and DPPH radical scavenging activity of the ethanolic extract of rosehip seed press cake using standard methods and DPPH assay.&#x0D; Study Design:  This is an experimental laboratory report on the phytochemical properties and antioxidant potential of the ethanolic semi-solid extract (ESE) of rosehip seed press cake in order to assess its commercial viability as a food supplement.&#x0D; Place and Duration of Study:  The work was conducted in the Department of Chemistry, National University of Lesotho, from August 2019 to March 2020. &#x0D; Methodology: Ethanol was used for the extraction of the semi-solid extract (ESE) from the rosehip seed press cake. The ESE was analysed for phytochemical constituents using standard methods. In vitro antioxidant activity of the ESE was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. For data analysis, mean and standard deviation were computed for each parameter that was quantitatively determined.&#x0D; Results: Presence of flavonoids, alkaloids, terpenoids, sterols, glycosides, reducing sugars, proteins, amino acids, fatty acids, phenols and polyphenols in the ESE was confirmed. Total phenolics and flavonoids content were found to be 134.44 mg GAE/g DW and 73.23 mg QE/g DW, in the range of 200 to 3000 µg/ml respectively. The DPPH radical scavenging activity of the extract was found to be in the range 10.32±3.89 and 76.06±3.48% within the concentration range and was very close to the scavenging activity of DPPH at concentrations ≥ 1500 µg/ml. The ESE showed an IC50 value of 1367.06 µg/ml relative to that of the positive control, ascorbic acid, being &lt;200 µg/ml.&#x0D; Conclusion: The ESE from the rosehip seed press cake was found to be very promising as a food supplement since 50% of the 16 screened phyto-constituents were present in high concentrations; 6.25% were detected in moderate concentrations and another 6.25% were present in low concentrations. Furthermore, the ESE exhibited antioxidant properties. Further studies are recommended to obtain more information on its composition and suitability additive in animal feed or as a food supplement.</jats:p

Antimicrobial properties of extracts from Euclea crispa subsp. crispa (Ebenaceae) towards human pathogens

Leaf samples of Euclea crispa subsp. crispa were collected in the Bloemfontein area of the Free State Province as part of a project to screen South African plants for their antimicrobial potential. Crude extracts were obtained with a 95% methanol solution and the aqueous fraction remaining after methanol was removed by distillation, was bioassayed in vitro for its potential to inhibit the growth of eleven human pathogenic bacteria and two human pathogenic fungi. Of all the plant extracts tested, the E. crispa crude leaf extract showed the most promising antimicrobial activity against human pathogenic bacteria and fungi. Subsequently, the crude extract was fractionated by means of liquid-liquid extraction using four different organic solvents in order of increasing polarity. Most of the antibacterial activity was observed in the more polar ethyl acetate fraction. No particular trend of inhibition was observed between the Gram-negative and Grampositive bacteria. Neither the crude extract nor the semipurified fractions inhibited the growth of Haemophilus influenzae, Klebsiella pneumoniae and Streptococcus pneumoniae. The growth of the other eight human pathogenic bacteria was inhibited to different degrees. Both the crude extract as well as all the semi-purified fractions inhibited the growth of two human pathogenic test fungi

Introduction of household biogas digesters in rural farming households of the Maluti-a-Phofung municipality, South Africa

The study aimed to introduce biogas as an alternative source of energy for rural cattle farmers in the Maluti-a-Phofung municipality in the Free State Province, South Africa. To augment the rural farming community’s adoption of the biodigester technology the following initiatives were undertaken: (i) a situational analysis (or diagnostic survey); (ii) training on biogas production in an integrated crop-livestock-bioenergy system; (iii) installation of the biodigesters; and (iv) monitoring and evaluation of the biogas production. Results on the diagnostic survey showed that the main source of energy for cooking was wood in all the farms and availability of water was not a constraint. Prefabricated biodigesters of 6m3 -12m3 were installed in all the households and, after continual feeding of the units with cattle dung, the production of biogas increased gradually. Monitoring of biogas production showed that, in two-thirds of the households, 80% of their cooking needs were met in summer, while in winter biogas production was minimal due to extremely cold weather. Challenges faced included non-adherence to a feeding regime – resulting in a blockage of the biodigester – and lack of feeding. Generally, farmers in the study area showed a high appreciation of the biodigester technology.</jats:p