Day 2 :
- Marine Plants | Medicinal Plants as Anti-Cancer Drugs | Traditional medicine | Herbal Sciences | Herbal Technology | Herbal Medicine | Plant Remedies | Aromatic Plant Sciences | Pharmacognosy | Phytochemistry | Phytochemical Evaluations | Naturopathic Medicine
Session Introduction
Anh V. Le
University of Newcastle, Australia
Title: The microwave- and ultrasonic-assisted aqueous extraction of bioactive compounds from Gac (Momordica cochinchinensis S.) seeds
Biography:
Anh Le is a current PhD student in Food Science at the University of Newcastle, Australia. She is a member of the research group working on Gac fruit (Momordica cochinchinensis Spreng). Her PhD project is about extraction of bioactives and oil from Gac seeds. Her research interest is looking for natural bioactives that can contribute to the improvement of the quality of human life whilst maintain the sustainability of natural resources.
Abstract:
Gac (Momordica cochinchinensis S.) seeds contain bioactive compounds with medicinal properties namely: trypsin inhibitors, saponins and phenolics. We hypothesised that microwave-assisted (MAE) and ultrasonic-assisted extraction (UAE) would be better than conventional aqueous extraction for recovering these bioactive compounds. The efficiency of extraction for the MAE and UAE techniques was also compared to other low alcohols solvents: methanol, 50% methanol, ethanol, 70% ethanol and water-saturated n-butanol.
Of all the methods, MAE achieved the highest extraction of phenolics (3.18 µg GAE g-1). Of the aqueous methods, MAE was also the best for saponins (19.04 mg AE g-1) but it did not improve the extraction of trypsin inhibitors, for which the conventional water extraction was the best (118.45 mg trypsin g-1). However, for saponins, water-saturated n-butanol and methanol extracts were the best overall (40.75 and 38.80 mg AE g-1, respectively). As a measure of antioxidant capacity, the ABTS assay gave highest value to MAE extract (23.92 µmol TE g-1) while the FRAP assay gave highest values to water-saturated butanol and 70% ethanol extracts (5.25 and 4.71 µmol TE g-1, respectively). UAE did not improve any extractions. Therefore, it is concluded that MAE was the best for extracting phenolics and the best aqueous method for extracting saponins while conventional extraction method was the best for extracting trypsin inhibitors in defatted Gac seeds.
Ahmed Hassanein
Central Laboratory of Genetic Engineering, Egypt
Title: Protocol to control obstacles retarding the application of tissue culture techniques to improve Moringa oleifera
Biography:
Abstract:
Despite the great nutritional and therapeutic importance of moringa, expansion of its cultivation needs to improve its ability to withstand various conditions. Artificial methods of plant improvement are based on tissue culture techniques. Thus, the goal of our work was to establish a successful protocol that ensures removal obstacles (vitrification and somaclonal variation) that previously detected during moringa micropropagation. Of all tested explants, media and cytokinin types, cotyledonary nodal segments in contact with cotyledons expressed the highest shoot multiplication, in particular, when they were cultured on MS medium containing 0.56 mg/l BAP. Verification symptoms including chlorosis, retardation of shoot formation and shoot length, necrosis of shoot tips, and formation of friable callus at the base of cultured explants were detected, they were controlled using ant-ethylene compounds (AgNO3, SA and CoCl2). In this work, effect of anti-ethylene compounds on genome stability during long term culture (14 subcultures) using molecular markers (RAPD, ISSR and SSR) was studied for the first time, they indicated that salicylic acid (50 µM) was the best, where it decreased vitrification as well as somaclonal variation. Study the expression of superoxide dismutases, peroxidases, catalases, esterases and glutamate oxaloacetate transaminases indicated that shoot multiplication without somaclonal variation was obtained up to seven subcultures. Among different concentrations of the tested auxins (IAA, NAA and IBA), 0.5 mg/L IAA was best to form roots without callus formation which facilitate acclimatization and transfer plantlets to open conditions. Root formation on auxin containing medium was affected by cytokinin type during shoot multiplication, where microshoots cultured on MS with 0.56 mg/L BAP for shoot multiplication followed by MS with 0.5 IAA for root formation was better than those of 0.56 KIN followed by 0.5 IAA.
Biography:
Abstract:
Oral diseases are major health problems with dental caries and periodontal diseases among the most important preventable global infectious diseases. Oral health influences the general quality of life and poor oral health is linked to chronic conditions and systemic diseases. The association between oral diseases and the oral microbiota is well established. Of the more than 750 species of bacteria that inhabit the oral cavity, a number are implicated in oral diseases. The development of dental caries involves acidogenic and aciduric Gram-positive bacteria (mutans streptococci, lactobacilli and actinomycetes). Periodontal diseases have been linked to anaerobic Gram-negative bacteria (Porphyromonas gingivalis, Actinobacillus, Prevotella and Fusobacterium). Given the incidence of oral disease, increased resistance by bacteria to antibiotics, adverse affects of some antibacterial agents currently used in dentistry and financial considerations in developing countries, there is a need for alternative prevention and treatment options that are safe, effective and economical. While several agents are commercially available, these chemicals can alter oral microbiota and have undesirable side-effects such as vomiting, diarrhea and tooth staining. Hence, the search for alternative products continues and natural phytochemicals isolated from plants used as traditional medicines are considered as good alternatives. In this review, plant extracts or phytochemicals that inhibit the growth of oral pathogens, reduce the development of biofilms and dental plaque, influence the adhesion of bacteria to surfaces and reduce the symptoms of oral diseases will be discussed further. Clinical studies that have investigated the safety and efficacy of such plant-derived medicines will also be described.
Biography:
Abstract:
Onion thrips, Thrips tabaci (Lindeman) (Thysanoptera: Thripidae) is the most serious insect pest of onions in Sudan. This study aimed to evaluate the effects of some botanical oils on thrips infesting onion. Field experiments were conducted at Gezira state during two winter seasons (2015/16-2016/17). Two experiments were conducted in the first season (2015/16) at the experimental farm of the University of Gezira and in the Gezira research Station Farm (GRSF) of the Agricultural Research Corporation (ARC). The third experiment was conducted in the second season (2016/17) for confirmatory studies at the (GRSF) in (ARC) and observation plot of 20 X 40 m2 was used to study the population dynamics of the thrips and natural enemies. The design of the experiments was randomized complete block design (RCBD) with four replications. Cotton oil, castor bean oil and bitter cucumber oil were applied at a concentration of 2.5% in the first season (2015/16). [b1] In the second season 50% upper and lower concentration of castor oil and bitter cucumber oil were applied at the rates of (1.25%, 2.5% and 3.75%). All oil treatments were effective against the onion thrips compared to the untreated control. Significant differences at P < 0.01 in the mean number of insects were found. Bitter cucumber oil was the most effective in reducing the number of thrips compared to the other two oils. A large number of natural enemies of thrips were found at the site associated with the trial. Orius bug and jumping spider were most abundant and by the end of the season these natural enemies had a role to decrease the number of onion thrips. [b2] No significant difference was observed between treatments in yield. This study recommends that, bitter cucumber crude oil at 1.25% concentrations can be used to reduce the number of onion thrips.
Ijeoma Solomon Okoro
Federal University of Agriculture, Nigeria
Title: Screening of Anthocleista djalonesis Fractions and Compounds against HIV-1 Integrase and HIV-1 Protease
Biography:
Okoro Ijeoma Solomon has completed her M.Sc in Chemistry from the University of Agriulture, Umudike, Nigeria in 2010. She has published 8 papers in various reputed national and international journals and authored one book. Her area of specialization is natural products chemistry. Currently she is doing her PhD in Chemistry at University of Agriculture, Makurdi, Nigeria. Her area of interests are phytochemical analysis and structural elucidation of the compounds isolated from plants.
Abstract:
HIV, the virus that causes AIDS, is one of the world’s deadliest diseases today. Drug resistance and narrow spectrum of available therapeutics is a main problem during HIV treatment. Therefore, new drugs effective against drug-resistant HIV strains are needed. The aim of this study was to screen Anthocleista djalonensis extracts, fractions and isolated compounds for in vitro anti-HIV-1 Integrase (HIV-1 IN) and HIV-1 Protease (HIV -1PR) activities. The ethyl acetate and acetone extracts of the roots of Anthocleista djalonensis and fractions and compounds obtained from column chromatography of acetone extract were screened for their inhibitory activity against HIV -1 Integrase using a non-radioactive ELISA-based HIV-1 integrase assay. The screening was carried out at concentration range of 10-5-102 ug/ml. The screening for anti-protease activity was performed using a fluorogenic octapeptide substrate, HIV-FRET (1) and a recombinant HIV-1 Protease solution. The ethyl acetate and acetone extracts showed inhibitoryeffects on HIV -1 Integrase with IC50 of 1.3001 ± 0.217 μg/mL and 0.7216 ± 0.0028 μg/mL respectively. IC50 values of 0.0077 ± 0.009 μg/mL, 5.0001± 0.1719 μg/mL, 3.5113 ± 0.3613 μg/mL and 0.0736 ± 0.0005 μg/ml were obtained for chromatographic fractions F-1, F-2, F-3 and F-4 respectively. The compounds Bauerenone, Bauerenol and a mixture of Stigmasterol and β-Sitosterol isolated from A. djalonensis had IC50 values of 5.6112 ± 0.8767 μg/mL, 4.8075 ± 0.0732 μg/mL and 0.8916 ± 0.0327 respectively. Bauerenone, Bauerenol and a mixture of Stigmasterol and β-Sitosterol isolated from A. djalonensis showed significant (P< 0.05) inhibitory activities against HIV-1 Integrase. However, there was no activity against HIV-1 protease at 50 μg/mL by the extracts, fractions and isolated compounds.