Carotenoids are secondary metabolite responsible for colored pigments in plants and microbes (Li et al., 2022). They are a class of C₄₀ tetraterpenoids consisting of eight isoprenoid units, and can be classified into carotenes and xanthophylls on the basis of their functional groups (Saini et al., 2015). Carotenes can be linear (phytoene, phytofluene, and ζ‍-carotene) or branched (β‍-carotene and α‍-carotene). Xanthophylls comprise β,β‍-xanthophylls (β‍-cryptoxanthin, zeaxanthin, violaxanthins, and neoxanthin) and β,ε‍-xanthophylls (α-cryptoxanthin, α-carotene, and lutein). Citrus fruits are complex sources of carotenoids, which are the principal pigments responsible for the typical orange color of most types (Chen, 2020). The difference in total carotenoid content and the diversity of carotenoid isomer proportion also accounts for other colors of citrus fruits, such as yellow, red, and pink (Chen, 2020).
Citrus/metabolism* ; Carotenoids ; Xanthophylls ; Lutein/metabolism* ; Zeaxanthins/metabolism* ; Fruit

To examine the substrate specificity of carotenoid 3',4'-desaturase (DR2250) from Deinococcus radiodurans, we amplified the dr2250 gene by using PCR methods. The PCR products were digested by Hind III-BamH I and ligated into the vector pUC19, yielding recombinant vector pUC-CRTD. We analyzed the carotenoids of E. coli transformants containing pACCRT-EBI(Eu) and (or) pRK-CRTC and (or) pUC-CRTD. Our results demonstrated that DR2250 had substrate specificity on the carotenoids with hydroxyl group at C1 (1').
Carotenoids ; biosynthesis ; genetics ; metabolism ; Deinococcus ; enzymology ; genetics ; Escherichia coli ; genetics ; metabolism ; Oxidoreductases ; metabolism ; Substrate Specificity

CRISPR-Cas9 gene editing technology has been widely used in Saccharomyces cerevisiae.However, the effects of Cas9, as an exogenous protein, on the growth and production of natural products in S.cerevisiae are still unclear.In this study, Cas9 gene was expressed in S.cerevisiae by integration into the genome and construction into vectors, and two natural products, carotenoid and miltiradiene, were selected as the target products to study the effects of Cas9 expression on yeast growth and production capacity.The results showed that whether Cas9 was integrated into the genome or expressed by vectors, Cas9 inhibited the growth of S.cerevisiae, which was more obvious in the form of genome integration.When Cas9 was integrated into the genome, it had no effect on the production of carotenoid and miltiradiene by S.cerevisiae, but when Cas9 was expressed by vectors, the ability of S.cerevisiae to produce carotenoids and miltiradiene was significantly reduced.Therefore, in order to further efficiently knock out Cas9 after gene editing and minimize the adverse impact of Ura3 and Trp1 vectors, this study systematically explored the removal efficiency of the two vectors, and a plasmid capable of efficient gene editing was constructed, which optimized the application of CRISPR-Cas9 gene editing system in S.cerevisiae, and provided reference for the application of gene editing technology based on Cas9.
Biological Products ; CRISPR-Cas Systems ; Carotenoids/metabolism* ; Gene Editing/methods* ; Saccharomyces cerevisiae/metabolism*

Phaffia rhodozyma is one of the organisms for production of astaxanthin, and the key process for extracting intracellular astaxanthin is cell disruption. In this work, cell disruption for extracting astaxanthin from Phaffia rhodozyma was studied with autoclave method at low acid concentration. The optimum disrupting conditions were: autoclave pressure 0.1 MPa, 121 degrees C; hydrochloric acid concentration 0.5 mol/L; liquid to material ratio (V/W) 30 mL/g dry cell weight and disruption time 2 min. Under the optimum conditions, medium scale experiment showed that astaxanthin and total carotenoids recovery from Phaffia rhodozyma were (84.8 +/- 3.2)% and (93.3 +/- 2)%, respectively. This new method can lead to no poisonous residues and get high extraction yield, which have good prospects to be put into industrial production.
Basidiomycota ; chemistry ; Carotenoids ; isolation & purification ; Cell Wall ; metabolism ; Hot Temperature ; Hydrochloric Acid ; Xanthophylls ; isolation & purification

Six kinds of elicitors were prepared respectively from Neurospora crassa, Monascus purpureus, Sporobolomyces roseus, Rhodotorula rubra, Nocardia sp. N89 and Actinoplanes sp. A05. When Penicillium sp. PT95 was incubated in Czapek's agar plates containing appropriate amounts of elicitors, both its sclerotia biomass and carotenoid content accumulated in sclerotia were enhanced significantly (P < 0.01). Among tested elicitors, the elicitors from the fungi N. crassa, M. purpureus, S.-roseus and R. rubra were more effective than those from the actinomycetes Nocardia sp. N89 and Actinoplanes sp. A05; the elicitor from M. purpureus gave the highest carotenoid yield of 599 micrograms/plate, 2.76 times higher than that of control. Every one of elicitors except that from M. purpureus could increase significantly the proportion of beta-carotene in total carotenoids (P < 0.01).
Actinomycetales ; physiology ; Biomass ; Carotenoids ; biosynthesis ; Neurospora crassa ; physiology ; Nocardia ; physiology ; Penicillium ; metabolism ; Rhodotorula ; physiology

For microbial production of lycopene, the lycopene synthetic genes from Pantoea agglomerans were integrated into Saccharomyces cerevisiae strain BY4742, to obtain strain ZD-L-000 for production of 0.17 mg · L(-1) lycopene. Improving supplies of isoprenoid precursors was then investigated for increasing lycopene production. Four key genes were chosen to be overexpressed, inclu- ding truncated 3-hydroxy-3-methylglutaryl-CoA reductase gene (tHMG1), which is the major rate-limiting enzyme in the mevalonate (MVA) pathway, a mutated global regulatory factor gene (upc2.1), a fusion gene of FPP synthase (ERG20) and endogenous GGPP synthase (BTS1), which is a key enzyme in the diterpenoid synthetic pathway, and GGPP synthase gene (SaGGPS) from Sulfolobus acidocaldarius. Over-expression of upc2.1 could not improve lycopene production, while over-expression of tHMGI , BTS1-ERG20 and SaGGPS genes led to 2-, 16. 9- and20. 5-fold increase of lycopene production, respectively. In addition, three effective genes, tHMG1, BTS1-ERG20 and SaGGPS, were integrated into rDNA sites of ZD-L-000, resulting in strain ZD-L-201 for production of 13.23 mg · L(-1) lycopene, which was 77-fold higher than that of the parent strain. Finally, two-phase extractive fermentation was performed. The titer of lycopene increased 10-fold to 135.21 mg · L(-1). The engineered yeast strains obtained in this work provided the basis for fermentative production of lycopene.
Bacterial Proteins ; genetics ; metabolism ; Biosynthetic Pathways ; Carotenoids ; biosynthesis ; Genes, Synthetic ; Genetic Engineering ; Pantoea ; enzymology ; genetics ; Saccharomyces cerevisiae ; genetics ; metabolism

BACKGROUNDEpidemiological studies have shown that lycopene has anti-prostate cancer effect. In vitro tests also confirmed that it can promote apoptosis of prostate cancer cells. We investigated the effect of whole-tomato supplement lycopene on the prostate-specific antigen velocity in selected prostate cancer patients.

METHODSTwenty selected prostate cancer patients were given whole-tomato supplement lycopene 10 mg per day for about 6 months. Blood samples of patients were collected weekly to measure serum prostate-specific antigen (PSA) values. PSA velocity slope, which reflects the change of PSA, and the degree of change were also calculated. By comparing the values of average PSA velocity slope (rise or fall of PSA) before and after the administration of lycopene, the effect of lycopene can be evaluated. Blood chemistry analysis was regular followed as safety control.

RESULTSThree patients in the research group withdrew within 3 weeks because of inability to conform. The rest 17 patients continued for an average period of 6 months. Two patients withdrew because of cancer progression (PSA rise) who later received active treatment. The average fall in PSA was equivalent to 2.56% over (i.e. an average slope/d of -0.000 28) the first 3 months. In the last 3 months, average fall in PSA was equivalent to 31.58% (i.e. an average slope/d of -0.003 51). The Wilcoxon rank-sum test showed a statistically significant decrease of PSA velocity slope overall (P = 0.000 9). Analysis of the PSA doubling time (pre- vs. post-treatment) showed a median increase over 3 months but this was not statistically significant (P = 0.21). No toxic side effect was observed during the whole process. The results indicate that the average PSA change is "decline" in patients, and the degree of the decline is accelerated.

CONCLUSIONAdministration of lycopene was able to reduce PSA velocity in this study group.

Aged ; Carotenoids ; therapeutic use ; Dietary Supplements ; Female ; Humans ; Male ; Prostate-Specific Antigen ; metabolism ; Prostatic Neoplasms ; blood ; drug therapy

OBJECTIVETo investigate the possible mechanism of lycopene on protecting against hypoxia/reoxygenation (H/R)-injury.

METHODSPrimary cultured cardiomyocytes, isolated from neonatal mouse, were divided into three groups randomly: control group (C) ; H/R group(4 h H followed by 8 h R); lycopene+H/R group(L+H/R), in which the cardiomyocytes were pretreated with lycopene for 4 h before H/R. The survival of cardiomyocytes was counted. Apoptotic cells were detected by TUNEL assays. The release of cytochrome c from mitochondrial matrix into the cytosol, the activity of caspase-3, intracellular ROS levels and the activity of calpain were also determined in these groups respectively at the same time.

RESULTSThe pretreatment of cardiomyocytes with lycopene significantly improved the survival of cardiomyocytes [C: (89.84 ± 5.15)%, H/R: (63.59 ± 5.11)%, L+H/R: (79.25 ± 1.48)%, P < 0.05] and reduced the extent of apoptosis [C: ( 10.37 ± 1.25)%, H/R: (32.03 ± 4.79)%, L+H/R: (22.57 ± 3.22)%, P < 0.05], significantly reduced caspase-3 activation [C: (2.61 ± 0.19), H/R: (5.82 ± 0.92), L+H/R: (3.74 ± 0.64) pNA pmol/µg protein, P < 0.05]. To further study the mechanism underlying the benefits of lycopene, interactions between lycopene and calpain activation were examined. Lycopene pretreatment of cardiomyocytes suppressed the activation of calpain(C:272.33 ± 300.46, H/R: 1156.00 ± 212.02, L+H/R: 607.33 ± 166.23, P < 0.05) by reducing the H/R induced increased intracellular ROS levels [C: 100%, H/R: (239.79 ± 27.27)%, L+H/R: (188.19 ± 17.63)%, P < 0.05].

CONCLUSIONLycopene may protect against hypoxia/reoxygenation-induced injury by preventing calpain activation.

Animals ; Apoptosis ; drug effects ; Calpain ; metabolism ; Carotenoids ; pharmacology ; Caspase 3 ; metabolism ; Cell Hypoxia ; Cells, Cultured ; Cytochromes c ; metabolism ; Mice ; Mice, Inbred C57BL ; Myocytes, Cardiac ; drug effects ; metabolism ; pathology

OBJECTIVETo study the protective effects of lycopene (LP) on cerebral ischemia-reperfusion injury induced by focal cerebral ischemia and oxidative stress in rats.

METHODS48 male Sprague-Dawley (SD) rats were randomly assigned into five groups: A (20 mg/kg LP), B (5 mg/kg LP), C (salad oil), D (salad oil) and E (basic feed control). A, B and C groups were given LP or salad oil orally for 15 d, then cerebral ischemia-reperfusion injury was established by middle cerebral artery occlusion (MCAO) and D group was used as fake surgery control. The contents of reactive oxygen species (ROS), nitric oxide (NO), lactic acid (LD) and the activities of nitric oxide synthetase (NOS) in cortex were measured at 24 h after reperfusion. The levels of HIF-1alpha mRNA and Bcl-2 mRNA in hippocampi were determined by using reverse transcription polymerase chain reaction (RT- PCR) technique.

RESULTSROS levels of A, B, C, D and E groups were (114.23 +/- 18.91), (135.89 +/- 14.17), (171.37 +/- 25.76), (94.24 +/- 2.23) and (92.06 +/- 5.59) fluorescence intensity value/g protein, respectively (F = 9.038, P < 0.01); levels of NO were (6.60 +/- 0.77), (7.13 +/- 0.47), (8.38 +/- 0.80), (5.52 +/- 0.16) and (5.23 +/- 0.51) micromol/g protein respectively (F = 10.197, P < 0.01); levels of NOS were (0.817 +/- 0.016), (0.875 +/- 0.095), (1.030 +/- 0.101), (0.557 +/- 0.094) and (0.595 +/- 0.066) U/mg protein respectively (F = 14.555, P < 0.01); levels of LD were (0.381 +/- 0.069), (0.446 +/- 0.012), (0.576 +/- 0.059), (0.359 +/- 0.021) and (0.310 +/- 0.036) mmol/g protein respectively (F = 10.043, P < 0.01); HIF-1alpha mRNA expression levels in hippocampi were 0.865 +/- 0.274, 0.635 +/- 0.069, 0.491 +/- 0.067, 0.375 +/- 0.052 and 0.361 +/- 0.087, respectively (F = 40.520, P < 0.01); and Bcl-2 mRNA expression levels in hippocampi were 0.263 +/- 0.033, 0.330 +/- 0.028, 0.198 +/- 0.034, 0.304 +/- 0.039 and 0.236 +/- 0.025, respectively (F = 11.003, P < 0.01).

CONCLUSIONThe protective effects of LP may be related with its abilities of decreasing ROS and LD cumulation, alleviating inflammation and up-regulating the expression of protective genes.

Animals ; Antioxidants ; pharmacology ; Brain Ischemia ; metabolism ; Carotenoids ; pharmacology ; Hippocampus ; metabolism ; Infarction, Middle Cerebral Artery ; metabolism ; Lactic Acid ; metabolism ; Male ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase ; metabolism ; Oxidative Stress ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species ; metabolism ; Reperfusion Injury ; metabolism

OBJECTIVETo study the hemiparasitic mechanism of Thesium chinense.

METHODThe anatomical structure of T. chinense was studied by using paraffin slice and electron microscope slice. Chlorophyll content was measured by UV spectrometry. Foliar photosynthesis (P(n)) and gas exchange were measured by using a LI-6400 photosynthesis system.

RESULTChloroplast possesses intact granal thylakoid system, lamella was strong. Vascular tissue of T. chinense was strong. Vessel aperture and its transport power were strong both in root and stem. There were many global haustoriums on lateral roots. Vascular tissues were strong inside haustorium, haustorial stylet penetrated epidermis and cortex of host root, and reached pith place, haustorial vessel was integrated with host root vessel. The maximum of P(n) of T. chinense reached 7.06 micromol x m(-2) x s(-1), its water use efficiency was lower, about 0.735 mmol x mol(-1), its transpiration varied notable in daytime and was relatively invariant at nighttime, and the value of daytime was greatly exceed that of nighttime.

CONCLUSIONT. chinense despoils water and nutrition from its host by haustorium. T. chinense can mostly be independent as for C supply by photosynthesis.

Carotenoids ; metabolism ; Cell Respiration ; Chlorophyll ; metabolism ; Photosynthesis ; Plant Leaves ; anatomy & histology ; metabolism ; Plant Roots ; anatomy & histology ; metabolism ; Plant Stems ; anatomy & histology ; metabolism ; Santalaceae ; anatomy & histology ; cytology ; metabolism ; Thylakoids ; metabolism ; Water ; metabolism