Objective: To investigate the impact of the extracts of Gac fruit parts (peel, pulp, seed, and aril) on the cell viability and angiogenesis markers of human retinal pigment epithelial (ARPE-19) cells under high glucose conditions. Methods: The effect of the extracts of Gac fruit peel, pulp, seed and aril on the ARPE-19 cells was determined using MTT viability assay, Trypan blue dye and morphological changes were observed using light microscopy. Enzyme-linked immunosorbent-based assay was performed to evaluate the effect of Gac fruit parts on the reactive oxygen species (ROS), vascular endothelial growth factor (VEGF) and pigmented epithelium-derived factor (PEDF) secretions. Results: High glucose (HG) at 30 mmol/L increased ARPE-19 cell viability and ROS and VEGF secretions. While, the exposure of ARPE-19 cells in high glucose condition to Gac fruit extracts led to inhibition of cell viability, induced morphological changes, decreased ROS and VEGF secretions, and increased PEDF level. Gac pulp, seed, and aril at 1 000 μg/mL showed significant inhibition activities [(7.5 ± 5.1)%, (2.7 ± 0.5)%, (3.2 ± 1.1)%, respectively] against HG-induced ARPE-19 cell viability. The findings also demonstrated that Gac aril at 250 μg/mL significantly decreased ROS and VEGF levels [(40.6 ± 3.3) pg/mL, (107.4 ± 48.3) pg/mL, respectively] compared to ROS [(71.7 ± 2.9) pg/mL] and VEGF [(606.9 ± 81.1) pg/mL] in HG untreated cells. Moreover, 250 μg/mL of Gac peel dramatically increased PEDF level [(18.2 ± 0.3) ng/mL] compared to that in HG untreated cells [(0.48 ± 0.39) ng/mL]. Conclusions: This study indicates that the extracts of Gac peel, pulp, seed and aril reduced cell viability, minimized ROS generations and showed angiogenic activities. Therefore, our findings open new insights into the potentiality of Gac fruit against HG-related diabetic retinopathy disease.

Introduction: This study was carried out to quantify the selected bioactive compounds (i.e., chlorogenic acids, caffeine, and N-methylpyridinium) in instant coffee and to analyze its correlation with the gastric release effect of the HGT-1 cell line. Methods: Selected bioactive compounds in regular (REG), low sugar (LS), low fat (LF), white coffee (WC), white coffee low acid (WCA), decaffeinated (DC), and instant black coffee (BC) were quantified using HPLCDAD (high-performance liquid chromatography diode array detection) system and flow cytometry analysis for its gastric release effect when treated with HGT-1 cell. Results: The HPLC data showed the content of caffeine (60,212 ± 212 µg/ml) and chlorogenic acid (35,779 ± 3027 µg/ml) were significantly high in BC while the lowest caffeine value was found in DC coffee. Chlorogenic acid in other instant coffee samples showed insignificant content distinctions. As for N-methylpyridinium (NMP), the highest content was found in BC (565 µg/ml) and the lowest value was detected in WC (52 µg/ml) coffee. Gastric release activity by HGT-1 cells was significantly higher in DC and REG coffee treatment. Pearson correlation showed no significant correlation between the quantitative data and gastric release activity by HGT-1 cells. Conclusion: The selected bioactive compounds contained in instant coffees were unable to stimulate gastric release.

Objective: To identify the bioactive extracts from Alternanthera sessilis and investigate its cytotoxicity potential against colon cancer cells, HT-29. Methods: This study examined the effects of three parts (aerial, leaf, stem) of whole plant on HT-29 colon cancer cell lines. Three different extracts from the plant parts were prepared by maceration technique using 80% ethanol. The anticancer activities were determined using MTT, clonogenic, cell motility and AOPI assay. The chemical composition profiling was analyzed by GC-MS. Results: Among three plant part extracts, leaf extract greatly suppressed the growth of colon cancer cells in time and dosage-dependent manner, followed by aerial and stem. The cytotoxicity results were rationalized with clonogenic, cell motility and AO/PI assay, where extract showed the most active activity compared to aerial and stem extracts. GC-MS analysis of leaf extract showed there were various recognized anti-cancer, anti-oxidant and anti-inflammatory compounds. Conclusions: Amid the screened extracts, the leaf extract exhibits the credible cytotoxic, anti-proliferative and apoptotic activity and hence, our findings call for additional research to conclude the active compounds and their mechanisms determining the apoptotic activity.

Introduction: Moringa oleifera Lam. is a miracle tree that has been widely utilised in folklore medicine due to its immense amount of phenolic constituents that could treat various ailments. Different techniques have been implemented to extract the phenolic but the parameters may not be optimised to further enhance the amount of phenolic extracted. Thus, the work aimed to enhance phenolic content and antioxidant activity of M. oleifera through RSM methodology, which is rapid and convenience. Methods: At first, antioxidant activity of different parts of M. oleifera (leaves, stem, pod and seed) were investigated. The plant part with the highest antioxidant activity was selected for the optimisation of extraction condition using RSM. In RSM, temperature (XA), extraction time (XB) and solid-liquid ratio (XC) were employed to study the effects on yield, total phenolics, flavonoids and antioxidant activity. Then, the optimum extraction condition obtained via RSM was utilised in LC-MS and HPLC analysis to determine the potential bioactive constituents. Results: The leaves of M. oleifera displayed the highest antioxidant activity as compared to other plant parts. The optimum extraction condition obtained for the leaves extract was: temperature (XA): 82°C, extraction time (XB): 48 min and solid-liquid ratio (XC): 1:30 g/mL (w/v). Meanwhile, LC-MS revealed the presence of gallic acid, chlorogenic acid, quercetin, kaempferol and 3-O-glucoside kaempferol. HPLC analysis detected six compounds; gallic acid, epicatechin gallate, chlorogenic acid, myricetin, quercetin and kaempferol. Conclusion: The optimisation are promising to improve yield and antioxidant activity in M. oleifera as compared to non-conventional extractions.

Introduction: There are numerous studies on the therapeutic properties of Artocarpus heterophyllus. However, studies on the aqueous extraction of A. heterophyllus leaves are limited. This present study was conducted to optimize the extraction conditions of A. heterophyllus leaves to yield the highest phenolic, flavonoids and antioxidant contents. Methods: Response surface methodology (RSM) was employed to obtain a higher phenolic extraction parameter(s) of A. heterophyllus leaves using Central Composite Design (CCD). The antioxidant activity was then determined via ABTS (2,29-azinobis (3 ethylbenzothiazoline-6-sulfonic acid)) and DPPH (2,2-Diphenyl-1-picrylhydrazyl) assay and analysis of the individual phenolics was performed by high performance liquid chromatography (HPLC). Results: The optimum extraction conditions with higher phenolics content and antioxidant activity was achieved at 81°C, 100 min and 40 mL/g sample with a good desirability value of 0.87. Under these optimized parameters, total phenolics and flavonoids were 174.48 ± 4.05 mg GAE/g sample and 21.44 ± 0.05 mg RE/g sample, respectively. Meanwhile, antioxidant activity via ABTS and DPPH assays were 90.88% ± 0.09 and 87.22% ± 0.62, respectively. Finally, under optimal extraction conditions revealed 4 compounds identified as chlorogenic acid, quercetin, rutin and kaempferol. Conclusion: The optimisation are promising to improve phenolic yield and antioxidant activity in A. heterophyllus leaves. It also proved that A. heterophyllus leaves can be used as an alternative natural antioxidant especially in medicinal applications since all identified compound possess significant biological activities for human health.

Introduction: Manilkara zapota (L.) P. Royen or sapodilla is a fruit-bearing tree that has been cultivated mainly in tropical areas including Mexico and South East Asia. The fruits and the other parts of M. zapota plant have been used since ages ago for various medicinal purposes. However, the data on the antioxidant properties of various parts of M. zapota is limited. Therefore, we aimed to measure the content and capacity of antioxidants in various M. zapota plant parts and also to screen the phytoconstituents present in the part with the highest antioxidant content and capacity. Methods: The in vitro antioxidant evaluation including the content of total phenolic (TPC) and total flavonoids (TFC) as well as β-carotene bleaching and 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging ability of the leaves, seeds, flesh, and peels of M. zapota extracted by aqueous and ethanol were determined. The plant part that exhibited the highest TPC, TFC, and antioxidant capacity was selected for phytoconstituents identification using liquid chromatography mass spectrometry. Results: M. zapota leaves aqueous extract exhibited the highest TPC, TFC, and antioxidant capacities and therefore selected for phytoconstituents identification. Our study provide additional data in which a total of 39 phytoconstituents have been identified in the M. zapota leaves including m-coumaric acid, quinic acid, robinetinidol-4alpha-ol, isoorientin 6’’-O-caffeate, apocynin A, and C16 Sphinganine. Conclusion: Thus, our study revealed that M. zapota leaves aqueous extract has potential as a promising naturally-occurring antioxidant candidate which could be useful for medicinal and nutritional functions.

Introduction: The increase of Type 2 diabetes mellitus has prompted numerous research toward finding an alternative to manage the disease through the oxidant-antioxidant balance, mainly through bioactive compounds in natural products. This study explored the antioxidant and antidiabetic properties of phenolic-rich extract (PRE) from Stingless bee honey (SBH) (Heterotrigona itama) as therapeutic agent to restore the redox balance. Methods: The total phenolic content (TPC), total flavonoid content (TFC) and antioxidant assays of PRE and SBH, were determined to provide preliminary insight into the sample’s antioxidant properties, followed by high-performance liquid chromatography analysis of PRE. The antidiabetic potential of PRE and SBH were determined based on their inhibition against α-amylase and α-glucosidase enzymes. The cytotoxicity analysis of PRE was conducted on 3T3-L1 adipocytes and L6 muscle cells before the glucose uptake and cellular antioxidant analyses were performed on both cell lines, respectively. Results: PRE yielded higher TPC, TFC and antioxidant activities than SBH. The phytochemical profile of PRE comprises gallic acid, myricetin, kaempferol, epicatechin, chlorogenic acid, quercetin, syringic acid, and cinnamic acid. The results from carbohydrate enzymatic inhibitory assays collectively suggested that PRE exhibited more robust antidiabetic activities than SBH. PRE showed good glucose uptake stimulating and reactive oxygen species scavenging effects in those cell lines. Conclusion: Overall, PRE from SBH showed higher carbohydrate enzymatic inhibition, glucose uptake, and protection against intracellular oxidative stress, primarily due to its high antioxidant content and may serve as an alternative therapeutic agent for managing T2DM.