Asian Pacific Journal of Tropical Biomedicine

1062-1066

Authors: Noraziah Mohamad Zin, Juwairiah Remali, Mohd Nazir Nasrom, Shafariatul Akmar Ishak, Mohd Shukri Baba, Juriyati Jalil

Objective To determine ex vivo antimalarial activity and cytotoxicity of endophytic Streptomyces SUK 08 as well as the main core structure fractionated from its crude extract. Methods The activities of SUK 08 crude extract were evaluated by using the Plasmodium lactate dehydrogenase assay and synchronization test against rodent malaria parasite Plasmodium berghei, instead of human malarial parasite Plasmodium falciparum. The cytotoxicity of the crude extract was determined by MTT assay. The crude extract was analyzed by thin-layer chromatography and gas chromatography–mass spectrophotometry. Results The ethyl acetate crude extract showed very promising antimalarial activity with IC50 of 1.25 mg/mL. The synchronization tests showed that ethyl acetate extraction could inhibit all stages of the Plasmodium life cycle, but it was most effective at the Plasmodium ring stage. On the basis of a MTT assay on Chang Liver cells, ethyl acetate and ethanol demonstrated IC50 values of >1.0 mg/mL. The IC50 of parasitemia at 5% and 30% for this extract was lower than chloroquine. Thin-layer chromatography, with 1: 9 ratio of ethyl acetate: hexane, was used to isolate several distinct compounds. Based on gas chromatography–mass spectrophotometry analysis, three core structures were identified as cyclohexane, butyl propyl ester, and 2,3-heptanedione. Structurally, these compounds were similar to currently available antimalarial drugs. Conclusions The results suggest that compounds isolated from Streptomyces SUK 08 are viable antimalarial drug candidates that require further investigations.

1071–1078

Authors: Oladayo Amed Idris, Olubunmi Abosede Wintola, Anthony Jide Afolayan

Objective To evaluate the antioxidant activities and phytochemical content of the leaf and root extracts of Rumex crispus using the solvents extraction; methanol extract, ethanol extract, acetone extract (ACE), and water extract. Methods Total flavonoids content, total phenolic content, and total proanthocyanidin were evaluated using spectrophotometric equivalents of the standards, quercetin, gallic acid and catechin respectively. The antioxidant activities of the plant extracts were determined using ABTS, DPPH, ferric reducing antioxidant power, total antioxidant capacity and nitric oxide scavenging assays. Results The flavonoids and phenols contents of the extracts were in the range of (19.39 ± 4.08) to (526.23 ± 17.52) mg QE/g and (16.95 ± 12.03) to (240.68 ± 3.50) mg GAE/g, respectively. ACE of the leaf has the highest value of total flavonoids content (526.23 ± 17.52) mg QE/g while ACE of the root has the highest value of total phenolic content (240.68 ± 3.50) mg GAE/g. The highest content of total proanthocyanidin (645.38 ± 1.33) mg CE/g was in ACE of the root. Significant amounts of saponin and alkaloid were also present in the root and leaf extracts. All solvent fractions showed significant antioxidant activities (P < 0.05) with ACE of the root having the highest scavenging value as shown in DPPH, ABTS, total antioxidant capacity, nitric oxide and ferric reducing antioxidant power (IC50 = 0.014 mg/mL, <0.005 mg/mL, 0.048 mg/mL, 0.067 mg/mL, and 0.075 mg/mL, respectively). Conclusions In this study, the mean phytochemical content of the root of Rumex crispus is higher than that of the leaf and this may have contributed to its high antioxidant activities. This may also justify the frequent use of the root more than the leaves in traditional medicine for the cure of helminthic infections.

1085–1091

Authors: Ola Basa'ar, Samreen Fatema, Ali Alrabie, Mohammed Mohsin, Mazahar Farooqui

Objective To investigate the effect of temperature and pressure on supercritical CO2 extraction of Triognella foenum graecum Linn seeds, to determine the optimal condition which leads to highest percentage of the accumulative yield and revealing the chemical composition of supercritical CO2 extract. Methods Temperatures in the range of 40–60 °C and pressures in the range of 10–25 MPa were used. FTIR and GC–MS analysis were used to detect the bioactive compounds present in the extract. The broth dilution method and slope method were used to evaluate the anti-microbial and anti-tuberculosis activities and the in vitro anti-malarial assay was carried out according to the micro assay protocol of Rieckmann and his co-workers. Results The temperature was more affected than the pressure on the extraction performance and the highest yield of the extract (3.111%) was attained at 60 °C and 10 MPa. FTIR and GC–MS showed that the chemical composition of the extract included conjugated linoleic acid methyl ester as the major active principle (with concentration of 72.28%), followed by saturated fatty acid methyl esters (16.03%), steroids (8.09%) and organic siloxane compound (3.61%). The extract showed moderate anti-bacterial activity with MIC values 100, 250, 125 μg/mL towards Escherichia coli, Staphylococcus aureus and Streptococcus pyogenus respectively. It exhibited high inhibition effect towards the fungi Candida albican with MFC value (250 μg/mL). The extract had low anti-tuberculosis activity with MIC value (100 μg/mL) and comparable MIC value (0.29 μg/mL) towards Plasmodium flaciparum. Conclusions Supercritical CO2 extraction as alternate and green technology is performed successfully to extract the bioactive compounds from the seeds of T. foenum graecum Linn and it is concluded that this extract can be used as an alternate source of synthetic anti-biotic drugs.

1097–1106

Authors: Chetan Aware, Ravishankar Patil, Swaroopsingh Gaikwad, Shrirang Yadav, Vishwas Bapat, Jyoti Jadhav

Objective To investigate L-3, 4-dihydroxyphenylalanine (l-dopa, anti-Parkinson drug), anti-inflammatory activity, proximate nutritional composition and antioxidant potential of Mucuna macrocarpa (M. macrocarpa) beans. Methods l-dopa content was determined and quantified by high performance thin layer chromatography and reversed phase high-performance liquid chromatography (RP-HPLC) methods. Anti-inflammatory activity was performed by in vitro protein denaturation inhibition and human red blood cell membrane stabilisation activity. Proximate composition and elemental analysis were also investigated. The antioxidant potential (2,2-diphenyl-1-picrylhydrazyl, N-N-dimethyl-phenylenediamine and ferric-reducing antioxidant power) of M. macrocarpa beans were evaluated by using different extraction solvents. The RP-HPLC analysis also quantified significant phenolics such as gallic acid, tannic acid, p-hydroxybenzoic acid and p-coumaric acid. Results RP-HPLC quantification revealed that M. macrocarpa beans contain a high level of l-dopa [(115.41 ± 0.985) mg/g] which was the highest among the Mucuna species from Indian sub-continent. Water extract of seed powder showed strong anti-inflammatory and antioxidant potential. Proximate composition of M. macrocarpa beans revealed numerous nutritional and anti-nutritional components. RP-HPLC analysis of major phenolics such as tannic acid (43.795 mg/g), gallic acid (0.864 mg/g), p-coumaric acid (0.364 mg/g) and p-hydroxybenzoic acid (0.036 mg/g) quantified successfully from M. macrocarpa beans respectively. Conclusions This study suggests that M. macrocarpa is a potential source of l-dopa with promising anti-inflammatory, antioxidant and nutritional benefits.

1116–1119

Authors: Mireille Solange Nganga Nkanga, BenjaminLongo-Mbenza, PeterVandenberghe, Fons Verdonck, Venant Tchokonte-Nana, Nkama Claude Nlandu, Roth Laure Mapapa Miakassissa, Paul Roger Beia Kazadi, Antoine Lufimbo Katawandja, Jacques Bikaula Ngwidiwo, Ntolo Jean-Pierre Mufuta, Kuanda Thomas Solo, Mbombo Aurore Cecilia Orphée Beia

Objective To analyze the feasibility of detecting Ph1 in leukemia patients in the Kinshasa University Clinics in the Democratic Republic of Congo, at KU Leuven, Belgium. Methods Bone marrow and peripheral blood samples with chronic myeloid leukemia, acute myeloid leukemia or acute leukocytes leukemia were obtained from 32 patients in Kinshasa University clinics in the Democratic Republic of Congo and transferred to KU Leuven in Belgium for iFISH feasibility. Ph1 was detected by using a remote analysis of interphase fluorescence in situ hybridization (iFISH). Results Out of the 32 patients involved in this study, 65.6% (n = 21) of the cases were successfully tested, of which 52.4% (n = 11) were iFISH positives for the variant t(9;22) (presence of Ph1) in chronic myeloid leukemia samples and 47.6% (n = 10) negatives in all subtypes of hematological malignancies. However, there was a female predominance in chronic myeloid leukemia samples Ph1-positives by iFISH, whereas no sexual influence was observed on acute subtypes of leukemia. Conclusions iFISH analysis is feasible on samples obtained from remote sites in the Democratic Republic of Congo. However, the optimization of the sample storage is necessary to further improve iFISH's performance.

1125–1128

Authors: Shi-Jiao Yan, Yun-Qiang Chen, Jiao Chen, Chuan-Zhu Lv

Objective To investigate the model, quality as well as effect of teaching-in-English in five-year clinical medicine program of Hainan Medical University. Methods The questionnaire was carried out among clinical medicine undergraduates of 2012–2015 grades in Hainan Medical University, to investigate studying time, studying habits and the impact of teaching in English. Additionally results of CET-4, CET-6 and overseas internship from undergraduates of 2012–2015 grade, as well as the result of phased medical licensing examination and post-graduate entrance examination from undergraduates of 2012 were accordingly collected from the Teaching Management Department. Results For the Chinese students in international classes, the average time of self-study was 161.49 min, 58.3% had preview before classes, and 90.7% had habit of review after classes. Thus the first time pass rate, total pass rate, first time excellent rate and total excellent rate of CET-4 and CET-6 of international classes were significantly higher than those of regular classes. The result of post-graduate entrance examination in 2016 showed that the score, pass rate and acceptance rate of international classes of 2012 grade were significantly higher those of regular classes (P < 0.01). Conclusions Teaching-in-English reform in Hainan Medical University has achieved initial success. Chinese students from international classes are superior to those from regular classes in many aspects. However, there are still many problems, and effective measures should be implemented to promote teaching quality continuously.