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Selected extraction techniques were first compared for young Jasmine rice leaves, which were evaluated as a novel source of flavone derivatives. Microwave-assisted extraction (MAE), which outperformed other tested methods in terms of phenolic content and antioxidant activity, was then evaluated and optimized. I-optimal design with response surface methodology was used to investigate the effects of and optimize MAE conditions in terms of the extraction time, solvent-to-solid ratio and MW power with extractable isoorientin and isovitexin contents as responses. A ratio of 37.7:1 (mL: g) and specific input MW power of 6.68 W/g for 7.5 min were noted as the optimal condition, yielding isoorientin and isovitexin at 7.23 ± 0.23 and 1.12 ± 0.04 mg/g DW, respectively. Validation of the optimal conditions confirmed that all responses closely aligned with the predictions (error < 5%). The study reveals potential of young Jasmine rice leaves as a good alternative source of flavone derivatives and successfully introduces I-optimal design for plant materials extraction optimization, showcasing its uniqueness and addressing certain limitations of other commonly used experimental designs.

Calmodulin, a primary calcium sensor in eukaryotes, binds calcium and regulates the activity of effector proteins in response to calcium signals that evoked in response to abiotic and biotic stress. To identify physiological responses associated with improved tolerance under dehydration stress that may be regulated by calmodulin in rice, the transgenic rice overexpressing OsCaM1-1, the control, and the wild-type KDML105 differing in their dehydration tolerance were compared 24 h after exposure to dehydration stress. The results demonstrated a greater increase in relative water content, relative growth rate, abscisic acid, photosynthetic pigment and proline contents, and antioxidant activities in the transgenic rice plants, whereas Na/K and Na/Ca ratio, lipid peroxidation, and electrolytic leakage decreased. The OsCaM1-1gene overexpression in the transgenic rice showed greater tolerance to dehydration stress than non-transgenic rice, suggesting that OsCaM1-1might play an important role in mitigating dehydration stress.Graphical AbstractThe overexpression of OsCaM1-1in transgenic rice plants altered physiological responses, which led to improved dehydration stress tolerance in rice.

This study aimed to develop a novel coating material from Konjac Glucomannan Hydrolysate (KGMH) to flavone derivates from rice leaves extract (RLE). A suitable process for producing KGMH solution with different degrees of polymerization (DP) by enzymatic treatment was developed. Mannanase enzyme (250 and 150 units/g) were used in the hydrolysis process to obtain KGMH with lower (DP4 – 7) and higher DP (DP7 – 10), respectively. The solution was then used as a coating material in spray drying with an inlet air temperature of 190°C, and the powder characteristics were assessed. The results showed that although the KGMH produced a lower production yield (64% – 66%) compared to gum Arabic (72.45% ± 0.74%), KGMH was superior in terms of encapsulation efficiency of bioactive compounds (85% – 95%) and antioxidant activity retention (90% – 100%). FTIR spectra and X-ray diffraction confirmed the success of encapsulation by KGMH in the spray drying process. KGMH DP7-10 has successfully improved the bioaccessibility of Tricin O-glycoside after digestion. Furthermore, adding RLE encapsulated with KGMH enhanced and preserved tea products' bioactive compound content and antioxidant activity (3% – 10% lower than after 24 days of storage).

Cannabinoids, consiting of alkylresorcinol and monoterpene groups, are the unique secondary metabolites that are found only in Cannabis sativa. Tetrahydrocannabinol (THC), cannabidiol (CBD) and cannabichromene (CBC) are well known cannabinoids and their pharmacological properties have been extensively studied. Recently, biosynthetic pathways of these cannabinoids have been successfully established. Several biosynthetic enzymes including geranylpyrophosphate: olivetolate geranyltransferase, tetrahydrocannabinolic acid (THCA) synthase, cannabidiolic acid (CBDA) synthase and cannabichromenic acid (CBCA) synthase have been purified from young rapidly expanding leaves of C. sativa. In addition, molecular cloning, characterization and localization of THCA synthase have been recently reported. THCA and cannabigerolic acid (CBGA), its substrate, were shown to be apoptosis-inducing agents that might play a role in plant defense. Transgenic tobacco hairy roots expressing THCA synthase can produce THCA upon feeding of CBGA. These results open the way for biotechnological production of cannabinoids in the future.

Camptothecin (CPT) and its derivatives have been received considerable attention recently. Two semi-synthetic derivatives, topotecan and irinotecan, are currently prescribed as anticancer drugs. Several more are now in clinical trial. CPT is produced in many plants belonging to unrelated orders of angiosperms. At present, CPT supplied for pharmaceutical use is extracted from the plants, Camptotheca acuminata and Nothapodytes foetida. Several efforts have been made to sustain a stable production of CPT by in vitro cell cultures of C. acuminata, N. foetida and Ophiorrhiza pumila. Recent report showed that plants are not the only sources that produce CPT. CPT was reported to be produced from the endophytic fungus isolated from the inner bark of N. foetida. The hairy root cultures of C. acuminata and O. pumila produce and secrete CPT into the medium in large quantities. These reports suggest the possibility to develop large-scale production of CPT. In addition, recent advance in the cloning and characterization of biosynthetic enzymes involved in CPT biosynthetic pathway provides valuable information for developing genetically engineered CPT-producing plants.

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.