Razauden Mohamed Zulkifli

Potential anti-dengue medicinal plants: A review

Dengue fever causes mortality and morbidity around the world, specifically in the Tropics and subtropic regions, which has been of major concern to governments and the World Health Organization (WHO). As a consequence, the search for new anti-dengue agents from medicinal plants has assumed more urgency than in the past. Medicinal plants have been used widely to treat a variety of vector ailments such as malaria. The demand for plant-based medicines is growing as they are generally considered to be safer, non-toxic and less harmful than synthetic drugs. This article reviews potential anti-dengue activities from plants distributed around the world. Sixty-nine studies from 1997 to 2012 describe 31 different species from 24 families that are known for their anti-dengue activities. About ten phytochemicals have been isolated from 11 species, among which are compounds with the potential for development of dengue treatment. Crude extracts and essential oils obtained from 31 species showed a broad activity against Flavivirus. Current studies show that natural products represent a rich potential source of new anti-dengue compounds. Further ethnobotanical surveys and laboratory investigations are needed established the potential of identified species in contributing to dengue control.

Chemical composition and biological activities of essential oil of Beilschmiedia pulverulenta

Abstract Context: The ethnopharmacological study of Beilschmiedia indicates that several species are used for the treatment of various ailments. Objective: This is the first study of the chemical composition of Beilschmiedia pulverulenta Kosterm (Lauraceae) essential oil and its antioxidant, antimicrobial, antityrosinase, anti-inflammatory, and anticholinesterase activities. Materials and methods: The antioxidant activities were evaluated by β-carotene, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, ferric-reducing antioxidant power (FRAP), and phenolic content at different concentrations. The antimicrobial activities against Gram-positive and Gram-negative bacteria and fungi were revealed by disk diffusion and microdilution. The antityrosinase and anti-inflammatory activities were assayed against mushroom tyrosinase and lipoxygenase enzymes. The anticholinesterase activity was analyzed using acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Results: Forty-two components were detected in B. pulverulenta oil with eugenol (45.3%) being the major component. The oil phenolic content and the FRAP were 660.1 mg gallic acid/g and 604.0 mg ascorbic acid/g, respectively. The oil gave an IC50 value of 94.5 µg/mL and an inhibition of 93.9% in DPPH and β-carotene, respectively. The antimicrobial activity showed that the oil had strong activity against all Gram-positive bacteria with an minimum inhibitory concentration (MIC) value each of 62.5 µg/mL and moderate against all fungi with MIC and minimum bactericidal concentration (MBC) values each of 125 µg/mL. The oil showed significant antityrosinase and anti-inflammatory activities with 67.6 and 62.5% inhibition, respectively. In addition, the oil had moderate AChE (56.5%) and BChE (48.2%) activities. Discussion and conclusion: The results show that the oil could potentially be used for nutraceutical industries, food manufactures, and therapeutic agents against various diseases such as inflammation and rheumatism.

Cytotoxic effect of Annona muricata Linn leaves extract on Capan-1 cells -

Annona muricata Linn has been reported to contain valuable bioactive compounds known as Annonaceous acetogenins. These long chain fatty acids were widely discussed for its potential in promoting anticancer and anti-proliferative activity in various cancer cell lines. However, little study has been done on A. muricata effect in pancreatic cancer cells. In this study, the viability of Capan-1 after treatment with A. muricata extracts was determined by using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The results displayed that only hexane and commercialized extract inhibited cell proliferation in a concentration-dependent manner with IC25 varied ~7.8-8 μg/ml and ~0.9-1.0 μg/ml respectively. The data demonstrate that A. muricata hexane and commercialized extracts induced mild cytotoxicity in pancreatic cancer cells (Capan-1).

Apini and Meliponini foraging activities influence the phenolic content of different types of Malaysian honey

Malaysian honeys are produced by two main bee genera: Apis and Trigona. Each bee species has long been reported to exhibit unique foraging patterns and time, and it is very likely that bee foraging activities play a significant role in the phenolic composition of honeys. This work aims to justify the potential relationship between species-specific foraging activities and phenolic composition of honeys, to distinguish polyphenolic profiles and to identify possible floral markers in each type of Malaysian honey studied. Seventeen samples of Malaysian gelam, acacia, nenas, tualang, and kelulut honeys were analyzed using a high-performance liquid chromatography with diode array detector (HPLC-DAD). Total phenolic contents ranged from 1.92 to 14.84 mg/g of honey, in nenas and gelam honey, respectively. Fifteen phenolic compounds were identified, probably affected by the bee foraging preference. The highest number was seen in kelulut honey (Trigona spp.) while the lowest were in tualang honey (10 compounds, Apis dorsata). Apis cerana indica showed the highest phenolic acid and flavonoid contents (8.74 mg/g honey) compared to the other bee species, probably due to less selective floral preference, longer duration and early foraging time as well as small body size that influence their foraging activity. Similarity in two dominant polyphenols from polyhenolic profiles between acacia and tualang honeys (naringenin and ellagic acid), and between gelam and kelulut honeys (ellagic acid and benzoic acid) suggesting that the floral source of unifloral honey is an equally important food source for the analyzed multifloral honey, was confirmed by PCA analysis. This work assumes that competition between bee species for nectar and pollen might exist, affecting honey production and total polyphenolic content. From the results, some polyphenolic profiles could be regarded as possible floral markers of Malaysian unifloral honeys, with very consistent profiles observed in nenas honeys.

Cytotoxic and Antibacterial Evaluation of Coumarins and Chromanone Acid from Calophyllum symingtonianum

Calophyllum symingtonianum is a rare species from the Calophyllum genus that belongs to the Guttiferae family. Calophyllum has been recognized as a potential medicinal plant due to its many bioactive phytochemicals especially coumarins and chromanone acids. In this study, the cytotoxic activities against MCF-7 and A-549 and antibacterial activities towards S. aureus, B. subtilis, P. aeruginosa and E. Coli of three coumarins known as inophyllum D, inophyllum H and calanone as well as chromanone acid identified as isocordato-oblongic acid isolated from this plant were evaluated. Inophyllum H exhibited the highest IC50 values against MCF-7 at 25.56 μg/mL and A-549 at 26.41μg/mL. Isocordato-oblongic acid showed moderate antibacterial activity against S. aureus and B. subtilis at 125μg/mL and 62.5μg/mL, respectively. This study suggests C. symingtonianum as a potential plant for cytotoxic and antibacterial phytochemicals.

Essential oil compositions of Malaysian lauraceae: A mini review

Essential oils have been largely employed for human need due to their antibacterial, antifungal and insecticidal activities. At present, approximately 3000 essential oils are known, 300 of which are commercially important. Essential oils or some of their components are used in perfumes and make-up products, sanitary products, dentistry, agriculture, as food preservers and additives, and as natural remedies. The essential oil compositions of Malaysian Lauraceae family have been investigated for many years. In the recent years, studies on the essential oils of the species have been progressing and many of them have reported interesting pharmacological activities. In this article, we summarized and updated the chemical compositions and biological activities of Malaysian Lauraceae. Throughout our literature review, only four genera which are Lindera, Beilschmiedia, Litsea, and Cinnamomum have been studied for their essential oil compositions in Malaysia. They were found to contain mainly safrole, eugenol, linalool, camphor, benzyl benzoate or cinnamaldehyde as major components. There were significant priorities to find out the details of the chemical compositions of the essential oils from Malaysian Lauraceae. Therefore, more clinical studies on the toxicity of the essential oil of the species are also crucial to ensure their safety and to assess their eligibility to be used as the sources of modern medicines.

Isolation and Identification of Potential Antineoplastic Bioactive Phenolic Compounds in Malaysian Honeys

The role of honeys as chemopreventive agents was inferred from their phenolic composition. The present study aims to isolate and identify such phenolic compounds with anticarcinogenic potential from the sugar matrix of Malaysian honeys. Phenolic compounds in Malaysian Acacia, Gelam and Tualang honey samples were isolated using octadecyl (C18) silica solid phase extraction (SPE) technique and identification was performed using high-performance liquid chromatography (HPLC) with diode array detector (DAD). Identification of phenolic compounds was achieved by comparing chromatographic retention times of honey samples with those of authentic standard compounds. HPLC analysis confirmed the presence of anticancer phenolic compounds in all honey samples with considerable variation observed among both different and the same types of honey. Six flavonoids (quercetin, naringenin, kaempferol, rutin, hesperetin, and apigenin), two phenolic acids (p-coumaric acid, and ferulic acid) and two tannins (ellagic acid, and penta-O-galloyl-s-D-glucose [PGG]) were the bioactive anticancer compounds identified. The presence of PGG in Malaysian honey was described for the first time. This study concludes that these three types of Malaysian honey possessed anticancer properties at varying degrees. Their potential usage as natural anticancer therapeutic agents with numerous health benefits could be further explored and considered as an alternative for current anticancer drugs

Antioxidant and tyrosinase inhibition activities of α- mangostin and Garcinia mangostana Linn. pericarp extracts

The methanol, ethyl acetate and petroleum ether crude extracts of mangosteen pericarp and α- mangostin were evaluated for the antioxidant capacity and tyrosinase inhibition properties. The ferric reducing antioxidant power (FRAP) assay was used to investigate their antioxidant capacity. Tyrosinase inhibition effect was evaluated using mushroom tyrosinase inhibition assay. Methanol extract has higher antioxidant reducing capacity (m= 1.621), compared to the rest of the extracts. Meanwhile, ethyl acetate extract and α- mangostin showed potent tyrosinase inhibition activities as compared to Kojic acid, a well- known tyrosinase inhibitor. It is observed that tyrosinase inhibition effect is antioxidant independent as ethyl acetate extract possessed low antioxidant capacity. This study suggests direct tyrosinase inhibition by ethyl acetate extract of Garcinia mangostana.

Bioactive compounds and antioxidant activity analysis of Malaysian pineapple cultivars

Pineapple industry is one of the important agricultural sectors in Malaysia with 76 cultivars planted throughout the country. This study aims to generate useful nutritional information as well as evaluating antioxidant properties of different pineapple commercial cultivars in Malaysia. The bioactive compound content and antioxidant capacity of ‘Josapine’, ‘Morris’ and ‘Sarawak’ pineapple (Ananas comosus) were studied. The pineapple varieties were collected at commercial maturity stage (20–40% yellowish of fruit peel) and the edible portion of the fruit was used as sample for evaluation. The bioactive compound of the fruit extracts were evaluated by total phenolic and tannin content assay while the antioxidant capacity was determined by ferric reducing antioxidant power (FRAP). From the results obtained, total phenolic and tannin content was highest for ‘Josapine’ followed by ‘Morris’ and ‘Sarawak’. With respect to FRAP, ‘Josapine’ showed highest reducing capacity, followed by ‘Morris’ and then ‘Sarawak’ having the least value. The bioactive compounds content are positively correlated with the antioxidant capacities of the pineapple extracts. This result indicates that the total phenolics and tannin content present in the pineapples may contribute to the antioxidant capacity of the pineapples.

Anti-oxidant properties and polyphenolic profile screening of Vitis vinifera stems and leaves crude extracts grown in Perlis, Malaysia

Grape has become a fast growing agricultural sector in Malaysia producing between 0.62 kg to 2.03 kg waste per vinestock. This study aims to generate useful information on anti-oxidative properties as well as polyphenolic composition of grapevine waste. Stems and leaves of Vitis vinifera cultivated in Perlis, Malaysia were extracted using methanol, ethyl acetate and petroleum ether. Ethyl acetate stems extract exhibited highest total phenolic content. While in DPPH assay, methanolic stems extract show the highest antioxidant activities. This result indicates that total phenolic content in the extracts may not contribute directly to the antioxidant activities. Thin Layer Chromatograms of all crude extracts exhibited good separation under solvent system petroleum ether-ethyl acetate (2:3) resulted in detection of resveratrol in ethyl acetate stems crude extract.