Copigmentation effect on red cabbage anthocyanins, investigation of their cellular viability and interaction mechanism

Anthocyanins (ANS) are an appealing substitute to synthetic colorants; but their practical applicability is limited due to low color stability. Copigmentation can improve both complex's color stability as well as intensity. In this study, we examined the interaction of red cabbage ANS with copigments i.e., two organic acid, two phenolic acid, a flavonoid and three amino acid through experimental and theoretical approach. Among various copigments, phenolic and organic acids induced a strong bathochromic shift of 6.5-7.1 nm and 5.1-11.6 nm. Thermal analysis, anthocyanin content and chromaticity, were used to assess the color intensity and stability of ANS, at 4 ℃, 25 ± 2 ℃, sunlight, oxygen, and heat. Results revealed that oxalic acid copigmented complex followed by chlorogenic and rosmarinic acid exhibits significant thermal stability with greater retention rate at 120 ℃ and 150 ℃. In case of anthocyanin content and colorimetric parameters, chlorogenic acid followed by oxalic and rosmarinic acid exhibits significantly improved stability. Rosmarinic acid copigmented sample showed good cell viability at high concentration (200 µg/mL). Steered molecular dynamics and thermodynamic analysis reveals chlorogenic and rosmarinic acid as promising copigments involving conventional H-bonds, π-π interactions, and carbon hydrogen bonds.

An Insight Review on Phytochemistry, Pharmacological Evidences, and Biosynthesis of Key Metabolites of Indian Himalayan Cherry (Prunus cerasoides Don.) with Emphasis on its Safety and Use in Tradtional Phytomedicine

Padmaka (Prunus cerasoides Don.), or wild Himalayan cherry, is a deciduous tree from the Rosaceaae family. The Prunus genus has 400-430 species, including shrubs and trees. It is widely distributed across the Himalayan region of India, China, Myanmar, Nepal, and Thailand. It is used in many classical formulations of various Asian traditional medicinal systems viz., Ayurveda, TCM (traditional Chineese Medicines) and TTM (Traditional Thai Medicines) for treating burning sensations, Blisters, blood disorders, dizziness, bleeding disorders, herps, and skin disorders. The present review covers the research updates on P. cerasoides from 1982 to 2023, accessible on scholars' platforms and databases. More than 200 phytomolecules have been investigated for their biological potential and the discovery of pharmacophores-inspired drugs. Padmaka instigated over fifty diverse phytochemicals, viz. flavones, isoflavones, chalcones, terpenoids, glycosides, and sterols. The phytochemical flux of P. cerasoides is dominant with phenylpropanoids, anthocyanins, carotenoids, and terpenoids. Several experimental shreds of evidence emphasized the biological significance of P. cerasoides extracts and their derived phytochemicals. Medicinal significance and its safety in clinical validation have been discussed efficiently. Moreover, the barrier in validated therapeutics is a lack of information on the bioavailability of specialized bioactive, standardization, safety, and toxicokinetic. This review also provides insight into discussions on the key specialized secondary metabolism in P. cerasoides responsible for pharmacological/therapeutic action.

Effect of co-pigments on anthocyanins of Rhododendron arboreum and insights into interaction mechanism

The impact of intermolecular copigmentation between five phenolic acids, two flavonoid and three amino acids with R. arboreum anthocyanins (ANS) and its isolated cyanidin-3-O-monoglycosides were investigated through experimental and theoretical approach. On addition of different copigments, phenolic acid induced strong hyperchromic (0.26-0.55 nm) and bathochromic shift (6.6-14.2 nm). The color intensity and stability of ANS with, storage at 4 °C & 25 °C, sunlight, oxidation and heat were evaluated by chromaticity, anthocyanin content, kinetic and structural simulation analysis. The strongest copigmentation reaction was observed with narningin (NA) and also showed high thermostability and highest half-life i.e. 3.39 h-1.24 h at 90-160 °C. The cyanidin-3-O-monoglycosides were analysed for their copigmentation effect and observations revealed that NA displayed best copigmentation effect to cyanidin-3-O-arabinoside (B) followed by cyanidin-3-O-galactoside (A), and cyanidin-3-O-rhamnoside (C). Additionally, structural simulation and steered molecular dynamics insights NA is the most favourable co-pigment involving π-π stacking and H-bonding.