Search results for "luonnonaine"

Salix spp. Bark Hot Water Extracts Show Antiviral, Antibacterial, and Antioxidant Activities—The Bioactive Properties of 16 Clones

2021

Funding Information: This work was supported by Business Finland corona-co-creation funding for the project Antiviral Fibers?pilot with extracts from Finnish forests (grant: 40699/31/2020). This study was also funded by the Natural Resources Institute Finland?s strategic research funding to the projects ?More, faster, higher quality: potential of short-rotation aspen and willow biomass for novel products in bioeconomy? (AspenWill) and ?Added value potential of new and under-utilized fibre sources in Finnish value networks of green bioeconomy: prefeasibility, prototyping, and market acceptance? (VALUEPOT). In addition, Academy of Finland has supported this study via the project ?Antivirals f…

Enzyme-assisted extraction of anthocyanins and other phenolic compounds from blackcurrant (Ribes nigrum L.) press cake: From processing to bioactivit…

2022

The effects of commercial enzymes (pectinases, cellulases, beta-1-3-glucanases, and pectin lyases) on the recovery of anthocyanins and polyphenols from blackcurrant press cake were studied considering two solid:solvent ratios (1:10 and 1:4 w/v). β-glucanase enabled the recovery of the highest total phenolic content – 1142 mg/100 g, and the extraction of anthocyanins was similar using all enzymes (∼400 mg/100 g). The use of cellulases and pectinases enhanced the extraction of antioxidants (DPPH − 1080 mg/100 g; CUPRAC – 3697 mg/100 g). The freeze-dried extracts presented antioxidant potential (CUPRAC, DPPH), which was associated with their biological effects in different systems: antiviral a…

Candida antarctica Lipase A-Based Enantiorecognition of a Highly Strained 4-Dibenzocyclooctynol (DIBO) Used for PET Imaging

2020

The enantiomers of aromatic 4-dibenzocyclooctynol (DIBO), used for radiolabeling and subsequent conjugation of biomolecules to form radioligands for positron emission tomography (PET), were separated by kinetic resolution using lipase A from Candida antarctica (CAL-A). In optimized conditions, (R)-DIBO [(R)-1, ee 95%] and its acetylated (S)-ester [(S)-2, ee 96%] were isolated. In silico docking results explained the ability of CAL-A to differentiate the enantiomers of DIBO and to accommodate various acyl donors. Anhydrous MgCl2 was used for binding water from the reaction medium and, thus, for obtaining higher conversion by preventing hydrolysis of the product (S)-2 into the starting materi…

Formal synthesis of ent-Cephalotaxine using a one-pot Parham-aldol sequence

2018

A short formal synthesis of ent-Cephalotaxine is achieved. The approach features a new Lewis acid mediated [2,3]-Stevens rearrangement of N-allylated prolineamide to generate a key quaternary stereogenic center. Additionally, a one-pot Parham–aldol sequence was developed to rapidly assembly two of the four rings in the cephalotaxine core. peerReviewed

Synthetic studies on 1-azabicyclo[5.3.0]decane alkaloids

2018

The first chapter introduces the reader to the concept of natural product total synthesis and its importance to chemistry, other sciences, and society. The second chapter reviews the chemistry of natural products containing 1-azabicyclo[5.3.0]decane motifs. This bicyclic motif and the natural products related to it, have been a continuous source of synthetic inspiration over the last decades. The second chapter of the thesis reviews the strategies and tactics developed. The third chapter covers the author’s total synthesis of stemoamide, a 1-azabicyclo[5.3.0]decane motif containing alkaloid. Additionally, two diastereomers of stemoamide were synthesized, allowing their structural reassignme…

Passerini- ja Ugi-reaktiot luonnonainesynteesissä

2015

Tämän pro gradu -tutkielman kirjallisessa osassa käsitellään Passerini- ja Ugi-reaktioita luonnonainesynteesin näkökulmasta. Lisäksi kirjallisessa osuudessa esitellään luonnonainesynteesejä joissa näitä multikomponenttireaktioita on hyödynnetty. Kirjallisen osan ensimmäinen puolisko alkaa lyhyellä johdannolla jossa esitellään luonnonainesynteesiä ja multikomponenttireaktioita yleisemmin. Tästä jatketaan Passerini- ja Ugi-reaktioihin ja niiden erityispiirteisiin. Luonnonainesynteesejä käsittelevät luvut on jaoteltu sen mukaan millaisia funktionaalisia ryhmiä Passerini- tai Ugi-reaktiolla on esiteltyihin luonnonaineisiin valmistettu, joko suoraan näillä reaktioilla tai niitä seuraavilla jatko…

Mukaiyama-Michael reactions with α-substituted acroleins - a useful tool for the synthesis of the pectenotoxins and other natural product targets

2013

Psychrophiles: A source of cold-adapted enzymes for energy efficient biotechnological industrial processes

2021

Biocatalysts are the backbone of bioprocessing industries that are going through a phase of transition with reference to the requirement of extraordinary enzymes for various biochemical processes. This transition is well reported and documented by various researchers through elucidation of different features and applications of mesophilic and thermophilic enzymes. However, there is little information available about psychrophilic enzymes and their involvement in industrial processes. Therefore, understanding the features and functions of psychrophilic enzymes could suggest some of their novel applications in various industries such as food, agriculture, chemicals, pharmaceuticals, and waste…

Generation and utilisation of natural product library for bioactivity screening and drug discovery

2006

Uusia lääkkeitä tarvitaan jatkuvasti. Koska luonnonaineet sisältävät bioaktiivisia yhdisteitä ja uusia kemiallisia rakenteita, ne tarjoavat lähes rajattoman uusien lääkeaineiden lähteen. Bioaktiivisuusseulontaan soveltuvan luonnonainekirjaston luomisen avulla voidaan luonnonaineisiin perustuvaa lääkekehitystutkimusta tehostaa lyhentäen prosessin normaalisti vaatimaa aikaa. Tässä työssä perustettiin luonnonaine (LA) kirjastojärjestelmä Lääkkeen keksintä- ja kehitysteknologian keskukselle (DDTC), joka on monitieteinen tutkimusyksikkö Helsingin yliopiston farmasian tiedekunnassa. Kokeellinen LA-kirjasto, joka sisältää sekä näytemateriaalia että tietokannan, perustettiin kesällä 2000 satunnaise…

Can foliar-applied nutrients improve caraway (Carum carvi L.) seed oil composition?

2021

Caraway seeds contain between 0.5–7% essential oil, rich in monoterpenes that have a characteristic aroma and chemical properties. Caraway oil has several bioactive compounds that are of industrial importance, particularly for pharmaceutical and health care products. Carvone and limonene are the main terpenes present in caraway oil, which along with some unique fatty acids (i.e. petroselinic acid) determine caraway (Carum carvi L.) oil quality. Both terpenes are important raw materials for industrial applications and their concentration influences the price of caraway seed and oil, hence there is need for identifying management practices that may increase the concentration of these and othe…