Optimization of solvent and extraction time on secondary metabolite content of mangosteen leaf (Garcinia mangostana L.) as a feed additive candidate on poultry

Objectives

This research aimed to determine the optimum type of solvent and extraction time to produce secondary metabolites (phenolics, flavonoids, tannins, and antioxidants) from mangosteen leaves (Garcinia mangostana L.) as feed additive candidates for poultry.

Materials and Methods

This research used a completely randomized design with a 2 × 5 factorial design with three replications. Factor A used two types of distilled water as a solvent (ordinary distilled water and distilled water heated at 100°C), while Factor B encompassed various extraction times (15, 30, 45, 60, and 75 min). The parameters assessed included total phenolic content (TPC), total flavonoid content (TFC), total tannin content (TTC), and overall antioxidant activity.

Results

The TPC, TFC, TTC, and total antioxidant activity all showed a highly significant interaction (p < 0.01) with the type of solvent and extraction duration.

Conclusion

The best solvent and time for mangosteen leaf extract to produce secondary metabolites, which can be candidates for feed additives in poultry, is ordinary distilled water for 45 min. In this research, the phenol content was 81.03%, flavonoids 11.07%, tannins 1.01%, and antioxidants 77.61%.

Green synthesis of silver nanoparticles using Vernonia amygdalina plant extract and its antimicrobial activities

The green nanoparticles synthesis method from leaves extract revealed full an economical, sustainable and eco-friendly method. In this study, the leaf extract of Vernonia amygdalina was as a reducing and capping agent for the synthesis of silver nanoparticles (AgNPs). M/DW binary solvent was selected for its relatively better extraction performance than methanol, ethanol, distilled water and ethanol/distilled water. Furthermore, the effect of solvent ratio of M/DW, precursor concentration, ratio of silver nitrate (AgNO₃) to plant extract, temperature, time and pH on the synthesis of AgNPs was carried out. Greenly synthesized Agents was confirmed using UV-Vis spectroscopy and characterized by XRD and FT-IR. Besides, its antimicrobial activities were also evaluated using agar diffusion techniques. The UV-Vis spectra showed specific Surface Plasmon Resonance (SPR) absorption peaks between 411 nm and 430 nm which revealed the formation of AgNPs during the synthesis. The nanoparticle synthesis was further confirmed by XRD analysis. Phytochemical screening test and FT-IR analysis of V. amygdalina leaves extract revealed the existence of phenolic, Tannin, saponins and flavonoid groups, which capped the nanoparticles during the synthesis. The antibacterial activities of the synthesized AgNPs were evaluated against Gram-positive bacteria (S. pyogenes and S. aureus) and Gram-negative bacteria (E. coli and P. aeruginosa) and higher inhibition zones were observed.

Cucumber mosaic virus infection modulated the phytochemical contents of Passiflora edulis

Cucumber mosaic virus (CMV) caused huge agricultural impact on Passiflora edulis. However, the interactions between CMV and P. edulis are poorly unknown, which lead to lack of prevention and control measures. In this study, we identified the infection of CMV in P. edulis through modern small RNA sequencing (sRNA-seq) technology combined with traditional electron microscope and polymerase chain reaction (PCR) methods. We also confirmed CMV infection adversely affected or modulated the contents of phytochemicals and further injured the development of P. edulis; inversely, P. edulis modulated its resistance to CMV stress by increasing the levels of secondary metabolites and the activities of antioxidant enzymes components. This is of significant importance to understand the interaction between virus infection and plant host.

Identification of Telosma mosaic virus infection in Passiflora edulis and its impact on phytochemical contents

Background

Viral disease has become the most severe constraint for the cultivation and production of Passiflora edulis in China. The infection of Telosma mosaic virus (TeMV), a potyvirus, and its effects on the phytochemical components of P. edulis remain largely unknown in China.

Methods

P. edulis plants showing distorted leaves and severe mosaic skin on green fruit were identified with TeMV infection through traditional transmission electron microscopy, RT-PCR and modern small RNA sequencing (sRNA-seq) platform. The contents of phytochemical components and the activities of antioxidative enzymes were compared between virus-infected and virus-free P. edulis to confirm the effects of TeMV infection on host plant.

Results

Firstly, approximately 700 nm linear virus particles, representing TeMV, were detected in infected P. edulis fruits and leaves with Electron microscopy. Partial coat protein genes of TeMV were successfully amplified by RT-PCR in infected P. edulis leaves and fruits but not in healthy plants. Abundant small interference RNAs (siRNAs) sequences, showing several characterizations, were specifically generated from the TeMV genome in infected plant fruits by sRNA-seq platform. Furthermore, fruit length, fruit thickness (wideness) and fruit weight decreased significantly due to TeMV infection. The levels of total protein and total sugar increased significantly; however, the level of total fat, total acid and vitamin C decreased obviously after TeMV infection. The level of total phenols, a secondary metabolite, was obviously higher in TeMV-infected than TeMV-free P. edulis fruit. The activities of superoxide dismutases (SOD) and catalases (CAT) obviously increased in TeMV-infected in comparison with healthy P. edulis fruit.

Conclusions

TeMV infection adversely affected the development of P. edulis fruits, differently and selectively modulated the phytochemical components of P. edulis fruits. In turn, P. edulis plants enhanced their tolerance to the stress of TeMV infection by increasing the secondary metabolite level and the antioxidative capacity. This is of significant importance to understand the effects of TeMV infection on the biochemical changes and the antioxidant defense mechanism in P. edulis.