Comparative account of vitamin C contents, antioxidant properties and iron contents of minor fruits in Sri Lanka

Sri Lanka is a habitat of diverse fruit varieties; nevertheless 95% of them are underutilized by people due to unawareness of their nutritional values and health aspects, and hence become ‘minor fruits’. This study was aimed on revealing vitamin C, iron and antioxidant contents of 29 varieties of minor fruits (MFs) with the comparison of the same with three best commonly consumable fruits (CFs), namely Carica papaya, Mangifera indica and Psidium guajava. Ascorbic acid (Asc), dehydroascorbic acid (DAsc), vitamin C (TC), phenolic (TP), flavonoid (TF), iron (Fe) contents and antioxidant capacities (AOCs) of fruits were determined using standard methods. The results of mean Asc, DAsc, TC, TP, TF and Fe contents in 100 gm of MFs ranged from 3.1 to 121.5 mg, 1.2 to 70.7 mg, 6.6 to 136.1 mg, 24.9 to 1613.3 mg Gallic acid equivalent, 6.2 to 228.0 mg Quercetin equivalents and 0.2 to 4.9 mg respectively. DPPH and Ferric Reducing Antioxidant Power (FRAP) assays were used for AOCs and variation of IC50 values in a DPPH assay was 1.2 to 245.4 mg/ml whereas FRAP values ranged from 9.6 to 486.7 ?mol FeSO4/gm. Among the studied minor fruits, Melastoma malabathricum (Maha bovitiya/ Malabar melastome) is found as the best respect to all considered parameters. As a conclusion, it can be stated that, the Sri Lankan minor fruits are good alternatives to the common fruits as they are recognized as good source of vitamin C, iron and higher content of antioxidants. As an outcome, Sri Lankan minor fruits can be promoted as alternatives to common fruits and as source of revenue for national economy

Effect of Extraction Techniques on Phytochemicals and Antioxidants Activity of Garcinia quaesita Leaves

Garcinia quaesita is an endemic plant in Sri Lanka with a wide array of domestic and medicinal values, yet very limited studies have been reported. The goal of this study was to investigate the phytochemicals and antioxidants capacity of leaves of G. quaesita under different extraction techniques in order to monitor the effect of extraction techniques on the above parameters. Water was used as the solvent and four extraction methods, namely sonication (EN01, one-hour,RT, 40 kHz), Soxhlet (EN02, six-hours, 105 ºC), maceration with agitation (EN03, six-hours, RT, 1000 rpm), and maceration with agitation upon heating (EN04, six-hours, 60 ºC, 1000 rpm), were applied. Phytochemical screenings and quantification of polyphenolics (TPC), flavonoids (TFC), tannins (TTC), terpenoids (TC), saponins (SC), and alkaloids (AC) were performed using standard methods, whereas antioxidants capacity was assessed using FRAP and DPPH assays. The results revealed that G. quaesita contains a wide range of phytochemicals and the TPC, TTC and SC profiles appeared to be higher in the extraction process of EN04 (60.73 ± 0.06 mg GAE/g, 60.12 ± 0.06 mg TAE/g, and 257.64 ± 0.72 mg SE/g, respectively) whereas those were lower in the technique EN01. In addition, TFC and TC levels were high in EN02 (3.02 ± 0.00 mg QE/g and 17.75 ± 0.04 mM LE/g respectively) and besides, TFC was low in method EN03, whereas TC was low in EN01. Interestingly, AC was found to be higher in EN03 (1.16 ± 0.03 mg AE/g) and lesser in EN02. Total antioxidant capacity ( FRAP value) was calculated to be higher in extraction method EN04 (72.08 ± 0.00 mg Trolox Eq/g) whereas it was lower in extraction method EN01. The method, EN03 gave the lower IC50 value in DPPH radical scavenging assay (10.49 ± 0.12 mg/ml), indicating high scavenging activity. In conclusion, the extraction technique EN04 is well suitable to extract polyphenolics and antioxidants from G. quaesita leaves. Though G. quaesita leaves contain a diverse range of bioactive compounds and antioxidants properties, it is important to choose the correct extraction technique based on the objectives of the desired research work, as the number of phytochemicals extracted, and antioxidant capacity varies depending on the extraction technique used. Full paper submission of ICIET 202

Phytochemistry and medicinal properties of Psidium guajava L. leaves: A review

Psidium guajava L. (Myrtaceae), also known as guava, is a medicinal tree native to tropical America that has been introduced and is widely available in many countries. Almost all plant parts of P. guajava have a long history of being used to treat a variety of ailments, in addition to applications as foods. Guava leaves are used as both medicine and food purposes, and there are numerous scientific reports on their medicinal uses, chemical composition and pharmacological properties. Cancer, blood pressure, diarrhea, bowel irregularities, diabetes, cough, cold, constipation, dysentery, scurvy, weight loss, improves skins tonicity are some of the diseases treated with guava leaves. Polyphenols, flavonoids, saponins, tannins, terpenoids, glycosides, flavones, cardiac glycosides, cardenolides, phlobatanins, steroids and other classes of bioactive compounds have been identified from the leaves. The primary chemical constituents of guava leaves are phenolic compounds, iso-flavonoids, gallic acid, catechin, quercetin, epicathechin, rutin, naringenin, kaempferol, caryophyllene oxide, p-selinene etc. Several studies have demonstrated its pharmacological activities including antioxidant, antimicrobial, antidiabetic, antitumor, anticancer, antidiarrheal, healing, cytotoxic, hepatoprotective, anti-inflammatory, antimalarial/ anti-plasmodial, dental plaque, antiglycative and many more. This review is aimed on compiling all the literature reported on pharmacological activities and phytochemical compositions of guava leaves as a support to the scientific community for further studies and to provide scientific data to validate its traditional uses

Microbial transformation of sesquitepenoid ketone, (+) Nootkatone by Macrophomia phaseolina

Microbial transformation is an effective tool for the structural modification of bioactive natural and synthetic compounds leading to synthesis of more potent derivatives. Its application in asymmetric synthesis is increasing due to its versatility and ease. This article presents biotransformation of sesquiterpenoid ketone, (+)-Nootkatone (1) by M. phaseolina, a plant pathogenic fungus. The transformation afforded four main compounds. They were determined to be 1:6 stereoisomeric mixture of 11,12-dihydroxy- 11,12-dihydronootkatone (2, 3), 13-hydroxynootkaone (4) and 12-hydroxy-11,12- dihydronootkatone (5) with the help of EI-MS, HR-FAB-MS(pos), HR-FAB-MS (neg), 1H-NMR, 13CNMR, COSY-450, NOESY, HMBC, HMQC spectral analyses. The compound 4 was firstchandana- amarasingha-samayawardana-avifauna-Bundala-1.1-28.07 identified as Nootkatone metabolites in this study. Further, the parental compound (1) and the transformed products 4 and 5 were found to be present significant antiprotozoal activity

Total Vitamin C, Ascorbic Acid, Dehydroascorbic Acid, Antioxidant Properties, and Iron Content of Underutilized and Commonly Consumed Fruits in Sri Lanka

Sri Lanka is rich in a wide diversity of fruits, but many are underutilized by the people in Sri Lanka despite their nutritional value. This is mainly due to little awareness of the palatability of many fruits and hence low popularity in the market. The present study aimed at providing comparative data on the main biochemical and nutritional parameters of thirty-seven (37) species of fruits grown in Sri Lanka, including 22 underutilized fruits and 15 commonly consumed fruits. The main parameters of the comparison were the contents of ascorbic acid (AA), total vitamin C (TVC), total phenolic content (TPC), total flavonoid content (TFC), total iron (Fe), and antioxidant capacities (ACs). The mean AA, TVC, TPC, TFC, and Fe contents in 100 g of fresh edible portions of fruits ranged from 2.0 to 185.0 mg, 8.1 to 529.6 mg, 12.9 to 2701.7 mg gallic acid equivalent, 0.2 to 117.5 mg quercetin equivalents, and 0.1 to 1.1 mg, respectively. The IC50 values in a DPPH assay varied between 0.8 to 1856.7 mg/mL and FRAP values in a FRAP assay ranged from 4.2 to 2070 μmol FeSO4/g in the studied fruits. Fruits were ranked based on the levels of the abovementioned biochemical properties. Using this ranking, 12 of the top 15 fruits were underutilized. Phyllanthus emblica (Indian gooseberry) is at the top of these underutilized fruits, and Psidium guajava (guava) is the best among commonly consumed fruits. These results indicate that underutilized fruits in Sri Lanka can be recommended as high quality and low-cost alternatives for securing nutritional requirements. Hence, underutilized fruits can be promoted as healthy additional fruits in Sri Lanka

Novel mutation in the SLC12A3 gene in a Sri Lankan family with Gitelman syndrome & coexistent diabetes: a case report

Abstract Background Gitelman syndrome (GS) is a rare autosomal recessively inherited salt-wasting tubulopathy associated with mutations in the SLC12A3 gene, which encodes for NaCl cotransporter (NCC) in the kidney. Case presentation In this report, we describe two siblings from a Sri Lankan non-consanguineous family presenting with hypokalaemia associated with renal potassium wasting, hypomagnesemia, hypocalciuria and hypereninemic hyperaldosteronism with normal blood pressure. Genetic testing showed that both were homozygotes for a novel missense mutation in exon 10 of the SLC12A3 gene [NM_000339.2, c.1276A > T; p.N426Y], which has not previously been reported in the literature in association with GS. Their mother was a heterozygous carrier for the same mutation. The father was not alive at the time of testing. This novel mutation extends the spectrum of known SLC12A3 gene mutations and further supports the allelic heterogeneity of GS. Interestingly both siblings had young onset Diabetes with strong family history. Conclusion These findings have implications in providing appropriate genetic counseling to the family with regard to the risk associated with inbreeding, the detection of carrier/presymptomatic relatives. It further expands the known spectrum of genotypic and phenotypic characteristics of Gitelman syndrome