Antioxidant Activities of Stem, Leaves and Fruits Extracts of Pepino (Solanum muricatum Aiton).

<b>Background and Objective:</b> Pepino (<i>Solanum muricatum</i> Aiton), rich with vitamin C and flavonoids, constitutes an abundant source of potent antioxidants. This research was conducted to determine antioxidant activity from three different parts of pepino based on equivalence with ascorbic acid, to analyze the relationship between total phenolic content (TPC) and total flavonoid content (TFC) on antioxidant activities and to determine flavonoid compounds. <b>Materials and Methods:</b> Antioxidant activities were determined using 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) and Cupric Ion Reducing Antioxidant Capacity (CUPRAC) methods. The TPC and TFC were determined by UV-visible spectrophotometry. The correlation between TPC, TFC and antioxidant activity was analyzed using Pearson's method. Flavonoid compound content was performed by HPLC. <b>Results:</b> The ethyl acetate pepino fruit extract expressed the highest antioxidant activity by DPPH and CUPRAC assays. The highest TPC was obtained from the ethyl acetate extract of pepino stem (18.493 g GAE/(100 g)), while the highest TFC was obtained from the hexane extract of pepino leaves (9.541 g QE/(100 g)). <b>Conclusion:</b> The DPPH and CUPRAC assays demonstrated that pepino exhibits potential as a source of natural antioxidants, especially in its fruit part.

Potential Antioxidative Activity of Waste Product of Purple Sweet Potato (Ipomoea batatas Lam.).

<b>Background and Objective:</b> Antioxidants are substances that can deactivate free radicals. Phenol and flavonoid are antioxidant compounds widely found in plants, including purple sweet potato (<i>Ipomoea batatas</i> L.). This research aimed to investigate three purple sweet potato-based organs' antioxidative activity and flavonoid contents. <b>Materials and Methods:</b> Antioxidative activities, total phenolic content and total flavonoid content were performed by UV-visible spectrophotometry. Pearson's method analyzed the correlation of TPC and TFC with antioxidative activities and the correlation between two antioxidative testing methods. <b>Results:</b> Antioxidative activity of three organs purple sweet potato using DPPH method showed values varied from 6.572-290.894 mg AAE g¹ and using CUPRAC method varied from 25.169-621.254 mg AAE g¹. The highest TPC was found in ethanolic leaves extract (20.885 g GAE 100 g¹), while the highest TFC was found in ethyl acetate leaves extract (10.048 g QE 100 g¹). <b>Conclusion:</b> DPPH and CUPRAC tests revealed that purple sweet potato leaves, stem and tuber extracts were potent antioxidants. The potential antioxidative activity was found in the waste product of purple sweet potatoes (leaves and stem). Phenol and flavonoid compounds had contributors to antioxidative activity. DPPH and CUPRAC methods gave linear results for most of the antioxidative activity in three organs of purple sweet potato. Ethanol stem extract contained luteolin 7-O-glucoside, rutin, quercetin, kaempferol and apigenin. Rutin had the highest content, which was 0.399%.

Effect of Banana (Musa sp.) Peels Extract in Nanoemulsion Dosage Forms for the Improvement of Memory: In Vitro & In Vivo Studies.

BACKGROUND: Banana (Musa sp.) is a plant rich in phytochemical compounds, especially antioxidants, which are hypothesized to inhibit the activity of acetylcholinesterase, an enzyme associated with Alzheimer's Disease. OBJECTIVE: This research aimed to study nanoemulsion preparations of Kepok banana (KEP-NE) and Tanduk banana (TAN-NE) peel extracts for their activities as antioxidants, acetylcholinesterase as well as tyrosinase inhibitors, and as agents to improve short-term memory. METHODS: Nanoemulsion was prepared using a combination of high shear homogenization and ultrasonication. The antioxidant activity test was carried out using DPPH and ABTS methods. Meanwhile, memory improvement was studied in a mouse model with memory impairment induced by alloxan (120 mg/kg b.w) using the Y-maze apparatus. ELISA performed determination of acetylcholinesterase and tyrosinase inhibition. RESULTS: Characterization of the nanoemulsion was performed to include particle size, antioxidant activity, acetylcholinesterase, and tyrosinase inhibition. The particle size and polydispersity index (PI) of KEP-NE and TAN-NE were 84.2 nm (PI: 0.280) and 94.1 nm (PI: 0.282), respectively. The antioxidant activity of DPPH showed that the respective IC50 values of KEP-NE and TAN-NE were 0.64 µg/mL and 1.97 µg/mL. At the same time, the values with the ABTS method were 1.10 µg/mL and 1.72 µg/mL, respectively. The IC50 of KEP-NE on acetylcholinesterase inhibition was 108.80 µg/mL, and that on tyrosinase inhibition was 251.47 µg/mL. The study of short-term memory in the Y-maze revealed that the groups Kepok peel extracts 100 and 300 mg/kg b.w and KEP-NE 100 and 300 mg/kg b.w significantly (P < 0.05) improved short-term memory. CONCLUSION: This study suggests that the nanoemulsion dosage form of Kepok banana peel extract has antioxidant and acetylcholinesterase inhibition and tyrosinase inhibition activities and could potentially be an adjunct alternative treatment for memory disorders. Modifying the smaller drug particle size contributes to the delivery system. The nanoemulsion can increase pharmacological activity.

Crystal Guava (Psidium guajava L. "Crystal"): Evaluation of In Vitro Antioxidant Capacities and Phytochemical Content.

Free radicals can cause many diseases, such as cancer. Antioxidant is a compound that could scavenge free radicals. One of the natural antioxidants is guava. The goals of this research were to investigate the antioxidant activity of leaves and fruit of crystal guava by determining the value of the Antioxidant Activity Index (AAI) using DPPH, CUPRAC, and FRAP; evaluate the total phenolic content (TPC) and total flavonoid content (TFC); analyse the correlation between the TPC and TFC with AAI DPPH, CUPRAC, and FRAP, and analyse the correlation between the 3 methods. Extraction was performed by the reflux method using n-hexane, ethyl acetate, and ethanol. Determination of AAI DPPH, CUPRAC, FRAP, the TPC, and the TFC was performed by UV-visible spectrophotometry. The correlation of the TPC and TFC with AAI DPPH, CUPRAC, and FRAP and, also, the correlation of the 3 methods were investigated by Pearson's method. The antioxidant activity of leaves and fruit extracts of crystal guava showed AAI DPPH in the range of 0.33-56.46, CUPRAC 0.20-7.31, and FRAP 1.65-59.89. The highest TPC was given by ethanol leaf extracts (49.55 ± 1.45 g GAE/100 g), while the highest TFC was for n-hexane leaf extracts (9.68 ± 0.210 g QE/100 g). The TPC of leaves extract had a significantly positive correlation with AAI DPPH, CUPRAC, and FRAP. AAI DPPH, AAI CUPRAC, and AAI FRAP of leaves and fruit extract of crystal guava showed a significantly positive correlation. In general, leaves extract had strong antioxidant activity by the three methods. For the highest antioxidant activity, ethanol was the best solvent for extraction leaves and ethyl acetate for extraction fruit of crystal guava. The TPC in leaves extract contributed to the antioxidant activity by DPPH, CUPRAC, and FRAP methods. The Antioxidant activity of leaves and fruit extracts of crystal guava was linear by the three methods.

Activity of Kaempferia pandurata (Roxb.) rhizome ethanol extract against MRSA, MRCNS, MSSA, Bacillus subtilis and Salmonella typhi.

Temu kunci (Kaempferia pandurata (Roxb.)) has a number of benefits and one of these is antibacterial. The rhizome is said to have antibacterial activity against Streptococcus mutans, Lactocillus sp. and Candida albicans. The aim of the study is to test the antibacterial activity of Kaempferia pandurata (Roxb.) rhizome ethanol extract on methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant coagulase negative Staphylococci (MRCNS), methicillin-sensitive Staphylococcus aureus (MSSA), Bacillus subtilis and Salmonella typhi. Antimicrobial activity of the extract was assayed by the microdilution method using Mueller Hinton Broth with sterilized 96 round-bottomed microwells to determine the Minimum Inhibitory Concentration (MIC) as well as to determine the time-kill activity. The MIC of the extract was 16 ppm for both Bacillus subtilis and MRSA; 8 ppm for both MSSA and Salmonella typhi and 4 ppm for MRCNS. Ethanol extract of Kaempferia pandurata (Roxb.) showed antibacterial activity against all the tested bacteria and was the most potent against MRCNS, with MIC 4 ppm. The killing profile test of the extract displayed bactericidal activity at 8-16 ppm against MRSA, MSSA, Bacillus subtilis and Salmonella typhi and bacteriostatic activity at 4 ppm towards MRCNS.